Cattle farm husbandry – the cow

Cattle, farming, husbandry, the cow, reproduction, oestrus signs and length, short cycle, silent heat, teaser bulls, artificial insemination, drying off, inductions ( abortions)

By Dr Clive Dalton

When will a cow come on heat?

• Cattle reach puberty about 6-9 months of age but some calves can come on heat as early as 4 months of age – especially rapidly-growing Friesian calves. Puberty depends more on weight than age.
• If you ever have calves that get pregnant, it’s best to have them aborted as soon as you notice excess udder development as there may be no other signs. Check with your veterinarian for the appropriate action.
• Dairy heifers are mated as yearlings at 12-14 months old to calve around 24 months.
• Gestation in the cow is 283 days but in the dairy industry 14 days either side of this time is accepted as normal variation in terms of deciding the sire of the calf.
• Beef heifers have not traditionally been mated as yearlings, but this is changing if they are well grown to get more profit from the enterprise.
  
• A cow will cycle (show oestrus or come on heat) about three weeks after calving, but it is more likely to be six weeks. Don’t mate her at that first 3-week cycle: leave her to her second cycle.
  
• She should then cycle every 21 days after that if not pregnant, with a range from 18-24 days.
• An unmated cow will cycle all year round with slightly less activity in winter.
• There are nymphomaniac cows that cycle every 3 weeks all year round and never get pregnant after mating. They are a great nuisance. If a cow doesn’t get pregnant after 3 cycles, then get rid of her.
  

How long does a cow stay on heat?

• She normally stays on heat for about 8 hours but this can vary from 4-12 hours. In the short days of winter heat periods can be at the lower end of the range.
• Oestrus will start off with low intensity, rising to a state of “standing heat” when the cow will stand quite still when mounted by other cows.
• If a bull then tries to mount her she’ll often not accept him straight away. This is nature’s way of teasing the bull to concentrate his sperm before ejaculation.
• After this, heat intensity decline as she goes off heat and she’ll let nothing mount her.
  

What are the signs of heat in cattle?

Cows coming on heat

• They will attempt to ride other cows but will not stand to be ridden themselves.
• They smell other cows around the genital area.
• Have a moist, red swollen vulva.
• Are restless, walk a lot and bellow for company of other cows.
  

Cows on heat

• Stand to be ridden and may also ride other cows.
• Hair will be rubbed off her tail head and muddy feet marks will appear on her flanks from being mounted.
• May stand with back arched and tail raised.
• Are nervous and excitable and graze less.
• Are restless, walk a lot and bellow for company of other cows.
• Have a moist red vulva with clear mucus coming from it.
• Dairy cows will hold their milk and often come into the parlour out of their normal order.
• Also watch any friendly heifers as they may try to mount their owners. It’s a bit scary to turn round and find a beast up on its hind legs about to land on you!
  

Cows going off heat

• Will not stand to be ridden any more but may attempt to rid others.
• The still smell other cows around the genital areas.
  

Sexually Active Groups (SAGs)

A SAG. The cow at right front is on heat, and the one waiting to mount her could be coming on. What about the other two watching the action? Are they coming on or going off?

This shows the value of observation skills and good records.

• Cows (especially in dairy herds) at various stages of their oestrus form groups of 2-6 sexually active cows referred to as a SAG.
  
• They are made up of cows coming on heat, those on heat and cows going off heat.
• They often rotate through the herd, forming, breaking up and reforming with new animals.
• With AI programmes it pays to keep good records of which animals have been inseminated to avoid confusion by this group behaviour.
  

What are short cycles?

• These are when a cow has been mated and comes on heat again after a shorter interval than the normal 18-24 days.
• Returning to oestrus in 10 days is a common abnormal interval. If this happens - mate the cow again and if possible use the same bull or semen to avoid confusion over parentage. If parentage is important then you can always have the calf DNA profiling to be certain of the sire.
  

What is a “silent heat”?

• This is when a cow fails to show outward heat signs but has ovulated (shed an egg). This can be confirmed through palpation of the ovaries by a veterinarian who can feel a Corpus Luteum or yellow body. This is where the follicle on the ovary has burst when the egg was shed.
• Silent heats are very frustrating as you have lost three weeks in time with no gain.
• The cow may have a silent heat for the first one after calving, and then start normal cycling after that.
• This problem has been reported to be more common in Friesian heifers than in Jerseys but the cause has not been fully investigated.
  
• If you have a cow that never cycles and vet inspection shows that she has had many ovulations – then get rid of her. Check her dam’s records and any other relatives in the herd as it could be a genetic problem.
  

Why do you use tail paint?

• Paint a short strip (100mm wide and 150mm long) along the tail head of the cow.
• Tail painting is a very cheap and easy way to identify cows coming into heat or on heat.
• When the cow is mounted by another cow, the paint will be scuffed and some rubbed off. It can be a good indicator along with other signs. She may also have skin rubbed off her back bone and muddy feet marks on her flanks.
• Buy the proper approved tail paint and follow the instructions.
• Use one colour and after the cow is mated change the colour. Use the traffic light colour sequence.
  

Can suckling calves delay return to oestrus?

• Yes it can.
• Suckling one calf will not delay heat much, but if you put more calves on a cow, then return to oestrus can be delayed by quite a few weeks due to the lactation drain on the cow.
  

Will a bull near by help cows come into heat?

• Yes - sometimes.
• Some dairy farmer experience shows that if the herd is slow to start cycling after calving, the sight, smell and sound of a nearby bull when walking past for milking will sometimes help stimulate their breeding cycle.
• Running a teaser bull with beef cows may also be worth trying but this means having access to one.
  

What is a teaser bull?

• A teaser bull is vasectomised so he is sexually active but does not ejaculate fertile semen.
• If fitted with a mating harness with coloured ink, teasers can identify cows on heat which can then be put up for AI.
• Teasers have all the dangers and disadvantages of keeping entire bulls so beware.
• Don’t keep them for more than one season as they often lose libido.
• If you get a bull vasectomised, get the vet to remove one testicle as a clear indicator of his status. It’s a lot easier than looking for a scar on the neck of his scrotum!
  

What is AI and AB?
Artificial Insemination (AI) also called Artificial Breeding (AB) in Australia and New Zealand, and is where semen is collected from a bull and after dilution is used either fresh or frozen to inseminate a cow on heat. For a successful programme you have to understand some facts about cow reproduction.

When is the best time to inseminate a cow?

• The best time is when she is going off heat, or has just gone off heat because this is when ovulation occurs.
• So in practice - if you see a cow on heat in the morning, have her inseminated in the afternoon of that day.
• If you see her on heat in the afternoon or evening, them inseminate her the next morning or early afternoon.
  

Where can you get an AI service?

• Look in the Yellow Pages of the telephone directory under Breeding Services. There is a wide choice of providers.
• Some organisations offer training so you can become a DIY operator, and some offer training with the proviso that you work for them for a period.
  

How to treat a cow after insemination?

• Quiet handling is important after insemination.
• Let her out of the bail into a small area on her own if she will stay there.
• If she’s getting upset at being on her own, give her a mate for company.
• Try to avoid putting her back with the rest of the cows till all her riding activity has stopped.
• Stray electricity. Check any troughs near your yards for stray voltage. There are cases of low conception rates when cows have drunk from troughs soon after insemination that were found to carry stray voltage from poorly-earthed fences.
  

Keep the records safe

• File the insemination certificates in a safe place.
• Mark on the calendar or wall chart the date 21 days after insemination, to watch to see if the cow returns to heat and needs a repeat insemination.
• But always watch out for short returns and file these records with the first insemination record as you’ll have to work out the calf’s correct sire when it is born in relation to the insemination date.
• Remember gestation in the cow is 283 days with a spread and 14 days either side of that is accepted as normal variation.

Reproductive technology

• This is a rapidly evolving area and it’s hard to keep up with developments.
• But there’s always a gap between what is possible in the lab and what you can achieve on the farm and at what cost.
  
• MOET – which is “multiple ovulation and ovum transfer” and is where you stimulate a cow to produce a lot of eggs. They can be fertilised naturally inside the cow after insemination or mating, or they can be flushed from the cow and fertilised with semen in the lab called IVF (in vitro fertilization).
• You can also collect the ovaries from old proven cows at slaughter and use the thousands of eggs still left that have not developed as future genetic resources.
• Eggs can now even be taken from young calves before puberty.
• Then there is cloning from body cells like Dolly the sheep that started from her mother’s udder cell. Cloning is now well established in cattle.
• Sexed semen has been on and off the market over the past decade but costs have so far restricted its widespread use.
• Just be aware that if you are going to submit a valuable cow to any of these modern technologies, you’ll have to accept variable results and with all the hormone treatment she will have, her natural reproductive life may be shortened. No doubt these risks will get less as time goes on.
  

How long will a cow keep on milking?

A dairy cow with good genetics will keep on producing milk for a couple of years without a pregnancy. Her yield will drop off to low levels after about a year but she’ll manage to produce about 3-4 litres/day for a very long time. The milk at these low levels of production may not be top quality as the cow’s udder is trying to shut down.

Drying off a lactating cow.

• This is best done by stopping milking completely or abruptly removing her calf.
• Never milk a cow every other day or increase the milking intervals before stopping and don’t let the calf back with the cow for any reason.
• Keep an eye on her for any sign of mastitis - red, swollen quarters that are painful to touch or her off colour and not eating.
• The teat canal must be allowed to seal naturally with a keratin plug, and milking or suckling again will reopen this and risk infection getting in.
• For cows that have had a lot of mastitis during lactation, talk to your vet about giving her “dry cow treatment” or DCT. You put a tube of long-lasting antibiotic up the teat into the udder where it remains active during the dry period to kill any infections that may arise. Don’t use DCT unless your vet recommends it and never use DCT antibiotics for lactation mastitis.
• You can also buy material to insert into the teat to seal it that has no antibiotic action.
• Before you put any product up a teat, be scrupulous about cleaning the end with meths and cotton wool until no more dirt comes off.
• The teat is the most sensitive part of a cow and they don’t like tubes pushed up them. So make sure she is well restrained and you are as gentle as possible.
  

Induction (abortion)

• This was a great idea when it was developed over 20 years ago to abort the calf so the cow could return to oestrus and get back on to a yearly calving cycle which is so important to farming cattle profitably in New Zealand.
• But this now has a terrible animal welfare image among the general public, and the veterinary profession is keen to restrict its use and operate under very strict guidelines. Discuss these with your veterinarian who is the only person licensed to administer the drugs.
• Don’t induce very old cows, heifers, skinny cows or any that had problems at calving.
• Induction can be used to abort a heifer that got inadvertently pregnant as a calf, so will calve as a yearling. This pregnancy will generally be too much for the young heifer and will affect her future production.
• The other reason for inducing a cow is when you expect her to have a massive calf and consequently calving trouble. So if you can get her to calve a week or so early, it may make the birth process easier for her and be less risk to both cow and calf. Again seek veterinary advice.
  

Intra-vaginal devices

• Intra-vaginal devices (IVDs) were also thought to be a great idea and the solution to getting cows to cycle that were slow to return to oestrus after calving. They were even promoted to improve herd fertility by ending up with less empty cows.
• IVDs are plastic devices that carry the hormone progesterone and are inserted in the cow’s vagina and left there for around 10-12 days.
  
• Progesterone tells the cow’s hormone system that it is pregnant so it stops cycling.
  
• When pulled out, the cows start cycling again and if a group has been treated, they will have their heat cycles and hence their calving dates synchronised.
• A cow that has not cycled after calving, treatment with an IVD may kick-start her system when it’s removed.
  
• As part of the programme, other hormones are used as well as progesterone to stimulate the egg follicle to ripen and then to burst and shed an egg.
• Like inductions, these now have a negative animal welfare image especially on women shoppers. And many farmers are now questioning the cost-benefit of their use.

Twinning
Farmers don't like twins, as they bring extra work and mortality is high. Added to that is the 'freemartin' problem in cattle where the female in a female-male pair is usually infertile.

But in recent years, because the theory makes sense - i.e. cows which produce and rear two calves are a lot more efficient as measured by 'weight of calf weaned/kg of cow live weight', interest has be renewed.

At Clay Centre Nebraska researchers have a herd of cows selected for twinning which has been increasing at 3%/year since 1984. Calf litter weight for twinning cows is 0.8-0.9kg of calf/kg of cow weight, compared to the singles at 0.5-0.55kg of calf/kg of cow weight.

But the twinning cows have 20% death rates among the calves, dystocia, and triplets which nobody wants. The twinning cows also have lower pregnancy rates than cows suckling singles. At present there is no enthusiam for the idea.

Disclaimer This material is provided in good faith for information purposes only, and the author does not accept any liability to any person for actions taken as a result of the information or advice (or the use of such information or advice) provided in these pages.

Sheep Farm Husbandry - Reproduction: The ewe and mating management

By Dr Clive Dalton

The breeding season


Sheep are seasonal breeders and in latitudes away from the equator, they are stimulated to cycle by the declining daylight pattern in autumn. If you move ewes between hemispheres they change their breeding season to suit the new light pattern. Sheep that are farmed near the tropics where there is equal daylight and dark tend to breed all year round. You can also modify the breeding season by putting sheep on artificial lighting indoors.

Puberty

• Female sheep reach puberty around 6 months old, depending on breed and live weight.
  
• Reaching puberty depends more on getting to a critical weight rather than being a specific age. Highly fertile breeds like Finn sheep have earlier puberty than meat breeds.
  

Oestrus and cycling

• Ewes are on heat (show oestrus) for around 24 hours, but there is enormous variation around this mean. It can vary from 4 hours to 72 hours depending on a range of factors such as age of the ewe, the breed, and especially contact with a ram.
• Ewes cycle (return to oestrus) every 17 days but again this can range from 14-20 days.
• If a viable embryo is not established, the ewe will start cycling again and return to oestrus (see conception below).
  

Signs of oestrus
Signs of oestrus in the ewe are not as obvious as in cattle. Look for these:

• The ewe will seek out a ram.
• She will sniff him and chase after him.
• She will crouch and urinate when a ram sniffs her side or genital area.
• She will fan her tail, perhaps defaecating when the ram sniffs her.
• When the ram is preparing to mount, she will turn her head to look at him.
• Ewes do not mount other ewes like cattle do.
• A ewe may bunt a ewe away from the ram seeking his undivided attention.

Mating sequence
The following pictures show the sequence of joining a ram with some ewes that had been totally isolated from a ram, but at a time in the mating season when they most likely would have started cycling. This was confirmed when a ewe was mated about 15 minutes after the ram was introduced.

Ram joins ewes and immediately starts sniffing their rear ends for any
that may be on heat. Note the ewes start sniffing the ram attracted by his sight and smell.

The ram has found a ewe that is either on heat or coming into heat.
She is standing still, starting to look back at the ram and tail fanning when sniffed.

The ram has chased the ewe around for a while (not his mouth open panting).
She stops and looks back at the ram waiting for him to mount.


The ram keeps checking, building up his libido.
The ewe keeps waiting


Ram still resting - ewe still waiting for action


Action at last. Note ram gripping ewe with his front legs while thrusting.

Conception

• The ram’s semen moves up through the ewe’s cervix, into the uterus and up the Fallopian tubes to meet and fertilise any eggs (ova) that have been shed from the ovary. Viable embryos will result that float around freely and are fed from the uterine fluids.
• By the third week, the embryo attaches to the wall of the uterus and the placenta starts to develop. On the dam there are buttons (caruncles) and on the lamb cotyledons grow and they are joined rather like Velcro through which nutrients and waste products flow.
• Week 4-10 sees great placental growth and it’s size is critical – the bigger it is the better for the embryo, the foetus and the eventual lamb.
• Each growing foetus has its own placenta but the number of caruncles on the uterus wall is limited to around 100-120 by the end of pregnancy, so they have to be shared among however many lambs will be present.
  
• So multiple lambs with fewer effective buttons will consequently get fewer nutrients than singles – and even if a foetus is reabsorbed, it’s too late for others to use the spare buttons to get more nutrients.
• From 20-30% of ova shed from the ovaries don’t end up as lambs – it seems as if nature keeps a close eye on possible overpopulation this way.
• The first 30 days after conception and in particular up to day 18 seems to be the worst time for embryo losses.
• A viable embryo at 13 days after conception is the signal for the uterus to establish a pregnancy which is done by complex hormone interactions – a major one being the growth of a “Corpus Luteum” (CL) or “yellow body” on the ovary which produces progesterone that tells the ovaries that the ewe is pregnant so no more ovulation is needed until further notice!
• The age at which the embryo is lost affects the ewe’s return to oestrus. If it’s lost after day 13 then oestrus will be delayed, but if lost before day 13 then the ewe will cycle again normally after 17 days.
• The information above may sound a bit academic but it has important practical implications for flock management immediately after joining.
  
• While these delicate hormone-controlled processes are going on, you would be most unwise to stress ewes in any way if it can be avoided (e.g. by shearing and yarding for any reason), and certainly not treat them with any internal or external chemicals – e.g. drench or dips chemicals float around in the blood stream.
• There may be no scientific evidence to confirm these warnings, but it’s not worth the risk to flock fertility – as it’s the main component of profit. We just don’t know enough about potential problems and disasters can be very expensive. Remember that consultants and veterinarians don’t pay farmers compensation for wrong advice!
  

Pregnancy
Pregnancy in the ewe averages 147 days but expect a wide range from 137 to 161 days. Ninety percent of pregnancies range from 145-155 days. The number of lambs carried will affect this with multiple births usually not going over time as much as singles do.

Flushing

• This practice is as old as sheep farming. The shepherd feeds the ewes on a rising plane of nutrition using specially saved feed for 2-3 weeks prior to joining with the rams.
• This stimulates the ovaries to shed more eggs and increase the chances of not just the ewe taking the ram early, but also increasing the number of multiple births.
• How good a result you get depends on a couple of things – benefits from the “static” effect and benefits from the “dynamic” effect.
• The old shepherds didn’t use this jargon but what it means is that there are benefits from having heavy ewes to start with as opposed to skinny ones (the static effect), and then benefits from increasing their weight (the dynamic effect) on top of this.
• The total benefit if things work out right can be 15-20% better lambing percentage, from better feeding 2-3 weeks before joining and another 3 weeks afterwards.
• Flushing doesn’t seem to affect the pattern of onset of oestrus and has no effect on the number of barren ewes in the flock.
• If you start off with skinny ewes off hard hill country at around 40kg, then don’t expect much of a flush. If you have heavier ewes of 50kg or more, then the result should be better.
• With high-fertility ewes these days it’s probably not worth bothering about flushing as they will shed plenty of eggs in any case. In fact, not flushing them may be attempted to cut down the number of multiple births (e.g. quads) but it’s not very effective.
• And you have to consider the costs involved. Some farmers may grow a special-purpose pasture or crop for flushing which can add greatly to the costs.
  

Mating different age groups of ewes

• Two-tooth ewes that have never met a ram before have slightly different mating behaviour. This may result in lower fertility if they are mated in a flock with older ewes that know the game so most farmers run their two-tooths separately to their older ewes – and with an older experienced ram.
• Similarly hoggets should be mated on their own with an older experienced ram.
• Old ewes seem to have more patience with a young inexperienced ram lambs, probably because they have a stronger heat that lasts longer.
  

Mating management
It’s a good idea to muster the ewes up with the ram at least once a day incase any ewes get isolated. This is not likely to happen in small flat paddocks but is certainly possible on large steep hill country blocks.

Shearing and dipping

• Shearing before joining depends on the shearing programme for the farm.
  
• Even with annual shearing, it’s been the normal practice based on old research with Romneys to shear two-tooths 3-4 weeks before joining to improve their fertility. With modern breeds this may not be necessary but the practice remains on some farms.
• Shearing should not be done very near to joining or in the 4-6 weeks after joining. The concern is the effect it has on ovulation before mating and embryo implantation after, so in the light of no conclusive evidence – don’t take the risk.
• Dipping should certainly not be done for 6 weeks before and 6 weeks after joining. Farmer experience with certain dips has shown bad effects on fertility so again in the light of no official research results – don’t take the risk
  

Out of season lambing

• In New Zealand this has to be achieved with intra-vaginal devices delivering hormones to stimulate the ewe to cycle after treatment.
• Even with the best of management, results are never as good as in the natural mating season in terms of the number of ewes that take the ram and ovulation rates.
• There are also substantial extra costs for the exercise which could not be recouped from the commercial lamb market in the past.
• Dorper rams have been claimed to stimulate ewes to cycle after weaning their lambs, and Poll Dorset rams have had the same effect on ewes – if they have been fed well.
• The price premium for out-of-season lamb certainly seems to be growing for supermarkets that want lamb all year round.
  

Disclaimer This material is provided in good faith for information purposes only, and the author does not accept any liability to any person for actions taken as a result of the information or advice (or the use of such information or advice) provided in these pages.

Animal behaviour and welfare: Sheep Part 2

SHEEP BEHAVIOUR BASICS: PART 2

Reproduction: Lambing: Lamb survival: Fostering

By Dr Clive Dalton

The ewe

• Sheep are seasonal breeders and ewes are stimulated to cycle by the declining daylight pattern in autumn.
  
• Female sheep reach puberty at about 6 months old, depending on breed and live weight.
  
• Only about 20% of farmers mate their ewe lambs and there is no problem getting these hoggets to come on heat if they have been well fed, and are a minimum of 35-40kg by 6-7 months old.
• Ewes come on heat every 17 days (14-20 days range) and will be on heat for about 4-8 hours.
• Pregnancy in the ewe is five months (154 days)

Signs of oestrus in the ewe
These are not very obvious compared to cattle. Here are some:

• The ewe will seek out a ram.
• She will sniff him and chase after him.
• She will crouch and urinate when a ram sniffs her side or genital area.
• She will fan her tail when the ram sniffs her.
• When the ram is preparing to mount, she will turn her head to look at him.
• Ewes do not mount other ewes as in cattle.

Ram has found ewe on heat. She stands still, looking around at the ram, tail fanning, ears pricked. She is waiting to be mounted.

The ram

• Rams reach puberty by about 6 months of age, but beware of younger ram lambs that miss docking as they could easily be fertile by autumn.
• Rams are most active in the autumn and are stimulated by declining daylight. They show a kind of "rut", but nothing as well developed as seen in goats or deer.
• They start to smell very strongly like a Billy goat approaching mating and the bare skin around their eyes and on their underside around front legs and crutch turns pink.
• This smell comes from the grease in the wool and contains a pheromone that stimulates the ewes to ovulate.
• Rams with high libido may not be fertile so fertility can be checked by a semen test using electro-ejaculation. This does not deliver the same quality of sperm as a good strong natural ejaculation but it is an indicator.
• To avoid problems, farmers usually change rams after each cycle to lessen the risk of a ram being a dud.
• Counting the number of mounts on a restrained ewe over time can also indicate libido, but seek veterinary advice on the ethics of this practice.
• It's wise to use an older experienced ram on young ewes and a young ram on older experience ewes. But some farmers argue the opposite and reckon the extra libido of young rams stimulated the young ewes better.
  
• As rams are reared in homosexual groups, they may take time to learn how to mate females correctly. Take time to watch new rams working to make sure they are serving correctly into the vagina and ejaculating. In a good ejaculation the ram will thrust forward with all four feet off the ground.
• Courting behaviour is made up of a lot of "sniff hunting" ewes. Rams approach a ewe often from side, pawing her side with his head low, rattling his tongue and giving a low bleating.

Ram 'sniff hunting' ewes.

• Mating ratios of 1 ram to 40-50 ewes is normal but a good fit ram will easily mate 100 ewes. Ram lambs that are large enough (30-40kg) are given 30 ewes.
  
• Having a surplus of rams in the flock may be a good insurance against infertility but they will spend more time fighting and establishing dominance and may miss ewes on heat. Fighting also leads to injuries which rarely recover before the end of mating, so an expensive ram is often a write off.
• In large mobs where many rams are used, the dominant rams do most of the mating, chasing the less-dominant away. Practice makes perfect, so these dominant rams, getting more practice do the job quicker and so get more work.
  
• The subordinate ram may get a service when the dominant one has moved away to find more fresh ewes, or with ewes that have come to him and are waiting. But it's just his luck if by the time it's his turn, the ewe is starting to go off heat and won't stand.
• Rams can be racists - in mixed-breed groups they often show a preference to mate ewes of their own breed.
  

The "ram effect"

• It's an old practice to use the sight and smell of a ram to stimulate ewes to cycle. It's called "the ram effect".
• To exploit it ewes are first isolated from sight, sound and smell of all rams for at least 2-3 weeks before joining.
• Then both sexes are put in adjoining paddocks to view and smell each other through the fence.
• After about 4 days the gate is opened between them and they are joined.
• This practice is sometimes done using teaser (vasectomised) rams that are actually put in with the ewes for even close contact and serving.
• Teasers lose their libido over time and young entire rams seem to have more stimulating power through the fence. The little bit of extra frustration seems to help.
  

Lambing

Ewe behaviour prior to lambing

• A few hours before lambing, a ewe will move away from the main flock to find a quiet birth site.
  
• Particular areas of lambing paddocks such as hollows or hill tops can be very popular spots and many lamb mix-ups and mismothering can happen here.
  
• It may be necessary to fence these areas off after a while when they get muddy. This will avoid a great deal of extra work and frustration for the shepherd.
• Ewes heavy in lamb become very quiet and near lambing are more vigilant and graze less. This restlessness lasts until the ewe finally selects a birth site.
  

On the birth site:

• The ewe paws the ground.
• She keeps turning round and round.
• She lies down and gets up a lot.
• Her waters burst and she gets up to smell the ground where it fell.
• Then after labour contractions the lambs will be born.
• The ewe then gets up and licks the lambs.
• The lamb may be finally delivered with the ewe standing.
• The ewe produces the afterbirth.
• She will remain on the site till the lambs have suckled.
• Ewes vary in the time they spend on the birth site.
• Old experienced ewes will move off as soon as the lambs have suckled and can move with her. These ewes with good maternal instincts and experience seem to be able to count and will not leave their lambs behind - going back to gather up stray twins or triplets. They stand with head down giving a low bleat and constantly nuzzling the lambs.
• Younger ewes with no previous experience will stay longer on the birth site, as they have the novelty of a lamb to deal with. If disturbed then these sheep panic more easily leading to lamb neglect.
• It's good practice to leave newly lambed ewes alone on their birth site, and only move them after a couple of days when they have clearly bonded and moved off to another area of the paddock themselves.
• Shifting ewes or lambs in the middle of the birth process is a disaster and will lead to mismothering of lambs.
• It's a good idea to spot mark multiples at birth and then leave them alone. This helps to ensure correct mothering later.
  

Burglar ewes

• Often a ewe that has not lambed will steal a lamb from a newly-lambed ewe as her maternal instincts have got out of phase.
• She can cause enormous disruption in a lambing paddock as you often don't know that she hasn't lambed until the day you find her with a lamb a few days old, and then a new one!
• The only cure is when you discover the trick is to shut her out of the lambing paddock until she has lambed or if she is near lambing, lamb her.
• Often you are tempted to put her in the killer's paddock when you discover what she's been up to and the trouble she has caused to your records!
  

Mothering and lamb survival

• Sheep are classical "follower species" where the lamb follows the ewe most of the daylight hours and right up to weaning.
• The lamb starts following movement immediately it is on its feet after birth. You'll see a very young lamb follow the shepherd, the dog or the bike, and this can lead to mismothering.
• Lambs learn to recognise their mothers by sight by about 3 days of age.
• Multiple births are common in sheep. Finnish Landrace sheep can even have litters up to 7-8. As the ewe has two teats, there is high mortality in these highly fertile breeds unless the lambs are artificially reared.
• Breeders once started to select sheep with four functional teats but this has not got very far.
• Good lamb survival depends on the ewe licking the lamb and the lamb finding the teat immediately after birth.
• Teat seeking behaviour is important. The lamb has got to be determined to get on its feet, start nuzzling the ewe to find an area of bare skin and find a teat to suck on.

A good ewe will stand still while the lamb is seeking the teat

• Some lambs find the skin under the front legs and waste time looking for a teat there before moving to the rear end of the ewe.
• A good ewe will encourage the lamb to move to the rear by standing still and nuzzling its rump and anal area.
• Inexperienced young ewes will not stand still and turn round to lick the lamb all the time. Lamb dies of starvation often through this overzealous mothering.
• Once the lamb has found the teat it will stand with head down reaching below the ewe, pushing upwards and once on the teat, wagging its tail while suckling. But don't assume that a lamb wagging its tail has always found the teat - check that its under belly is rounded and full of milk.

Lambs in the first 3 days :

A nice sunny sheltered spot to aid survival but where's its mother?

• Dystocia of single lambs that get too big and stick in the birth canal.
• Death of small multiple lambs that have not sucked.
• Lambs that die from wet and cold - hypothermia.
• Multiples left behind to starve when ewe takes off with one lamb.
• Lambs that suffocate as membranes around lamb have not broken at birth.
• Lambs that follow other ewes and are rejected. Not found again by own dam.
• Lambs that have slipped down steep hillsides away from their birth site.
• Lambs that die from haemorrhage as ewe has chewed the navel or tail
  

Bonding

• First sound then sight soon reinforce the ewe/lamb bond that was built initially on smell. The ewe recognises the lamb's bleat, and the lamb learns the ewe's call.
  
• This is important as lambs get older and spend time away from the ewe for short periods, e.g. with other lambs.
• Lambs show great play behaviour especially approaching dusk when they race along fences and play "king of the castle". They can often fall down holes and drown in water troughs during this activity.
• When danger is seen, the ewe first calls the lamb then checks its approaching identity by sight.
  

Triplet problems

A good ewe will recognise she has more than one lamb and mother them all

• The increasing fertility in modern sheep breeds has led to higher numbers of triplets and quads in commercial flocks.
• As a ewe only has two teats, inevitably there are higher death rates in these multiples and if they are reared, either on the ewe or artificially, it leads to many smaller lambs at weaning.
• Some farms now get up to 40% triplets and once litter size (number of lambs born/100 ewes lambing) gets over 2.2, an increasing number of quads are born which the ewe cannot rear.

With quads, at least one lamb has to be removed

• With triplets, observant farmers have noticed that between 10-15 days after birth, the ewe decides that she cannot feed all her lambs so she starts to leave one behind.
  
• The two that get to the udder first can soon drink all the milk so when it's the turn of the third lamb, there is no milk left. The neglected third lamb is found motherless in the paddock and will die if not removed and fed which may not be economic.
• Advisors recommend that ewes with twins and triplets are run together and ewes with singles grazed on their own.
  
• This is because there’s a better chance of multiples moving between dams than a ewe with a single accepting a stray multiple lamb.
  

Reviving starved lambs

• If a lamb is badly chilled and not had any colostrum, chances of survival are poor.
• Colostrum is vital – and it will have to be tube fed.
• Wrapping the lamb in an old electric blanket works best. It stays at constant heat.
• Bathing a starved lamb in a blood-heat water may work followed by placing them under a heat lamp. In the batch as the water cools, this effectively finishes the lamb off.
• Make sure you don’t overheat the lamb under the heat lamp.
• Vigorous rubbing with an old towel helps circulation followed by the heat lamp.
• Whisky or brandy was a traditional lamb “saviour” but it’s more effective if the shepherd takes it!
  

Fostering

A lamb on its own calling out and not full. Find its mother or else it could mean fostering or artificially rearing it with all the work involved

• Bonding of the ewe and lamb is very rapid at birth - it only takes a few minutes. Once the ewe has smelled the lamb she will not take a lamb that smells differently.
• To foster lambs on to ewes, there are a few tricks but realise that some ewes are more determined than others not to be fooled.
• To add a lamb to a ewe that already has a single, have the lamb ready and cover it in the ewe's birth fluids so both lambs smell the same. The fostered lamb will be more active so make sure the ewe licks her own lamb well and it gets a drink. It's best to artificially feed it to make sure it gets enough colostrum.
• For a ewe with a dead lamb, skin the dead lamb and make it into a suit with holes for legs to fit on the fostered lamb.
• Use strong smelling oil or commercial product to put on lamb and up the ewe's nostrils. This is not always effective.
• Put the ewe in close confinement or in a headbail and leave the lamb with her till she accepts it. This may take a few days and some ewes will win the battle with you and never take the lamb.
  

Animal behaviour and welfare: Horse Part 3

HORSE BEHAVIOUR BASICS: PART 3

Reproduction: Birth: Training

By Dr Clive Dalton

Reproduction

• Puberty in horses varies a lot with breed and it can occur from 8-24 months.
  
• Well-fed horses usually reach puberty at around 12 months, but feral horses would be much later.
• The mare's oestrous cycle is stimulated by increasing daylight so she is sexually active in spring and early summer.
• She comes into heat 4-18 days after foaling so the foal can be in a dangerous situation from the stallion wanting to mate her during this period in the wild.
  
• A mare is pregnant for 11 months and if not mated she will cycle every 3 weeks and she is on heat for 5-15 days.
• Sometimes you can get prolonged oestrus for several weeks (nymphomania) and it can be a real nuisance to the handlers.

Heat signs

• Plenty of vocalisation - especially if she sees other horses.
• Frequent stopping to urinate.
• Standing with hind legs parted and in a crouch with tail held up.
• Swollen vulva.
• Viscous vaginal fluid running from the vulva.
• Everting the vulva to expose the clitoris - called "clitoral flashing" or "winking"
• Restless - always looking for the company of other horses.
• Tail twitching.
• Stud mares are tested for standing oestrus using a "teaser" or small pony stallion that is too small to mate the mare. But don't believe that as some get very cunning!
• Mares not quite right on heat are happy to meet the stallion, but will squeal, kick and bite him when he tries to mount. They are best tested over a gate to prevent injury to both parties.
• A mare right on heat will stand firm when the stallion mounts and lean back to take his weight.
• After mating the stallion will stand around resting and the mare may come and try to stimulate him again.
  
• Hand mating can be a dangerous time for the handlers as there is always the risk of being kicked, stood on or bitten. Full protective clothing including head protection body armour and safety boots should be worn and strangers should be kept away.
• Mating is best done outside but if it is done indoors, make sure the roof is high enough so the mounted stallion does not injure his head on the roof beams. This has happened.
  

Birth behaviour

• Mares generally foal rapidly. First comes the initial stage when she prepares a birth site and gets ready to lie down. Then comes the delivery stage with the foal's head and front legs first like a diver, which is usually over in about 15 minutes.
• The foal is usually delivered with the mare resting and the membranes are burst when the foal hits the ground.
• So if there are delays in this procedure, which usually means problems, get veterinary attention urgently.
• There are more difficult births in thoroughbreds than other horse breeds/types.
• The mare should get up immediately and lick and chew the membranes, lessening the chances of the foal smothering. But an exhausted mare may not do this and the foal can be smothered.
• The mare should void the afterbirth in an hour and it's important to check this to avoid uterine infections.
• Bonding is done by the mare licking the foal, and it can spend several hours doing this. Licking helps blood circulation and warming the foal.
• Young mares (first time mothers) may strike the foal with their front feet. This may be a reaction to get it to stand and be ready to move off, to avoid predators being attracted by the birth site and afterbirth.
• About 80% of mares foal at night, peaking around midnight.
• A foal is usually on its feet in about 15 minutes.

• The foal's approach to the udder is important. It uses its long neck to avoid kicks and seeks out a warm area of bare skin where there should be a teat.
• Good mares will stand and encourage teat seeking by nuzzling the foal's rear end and genital area.
• Poor mares will keep moving and looking at the foal, preventing it getting round to her udder for a suck. It's vital that the foal has colostrum in the first 6-8 hours.
• A foal should suck within 30 mins of birth. It then sucks at frequent intervals of 50-75 times in 24 hours in the early weeks of life.
• Suckling lasts from 15 seconds to 2 minutes as the foal stands with legs apart and tail raised. It keeps well tucked in touching the mare's side.
• After the mare and foal move away from the birth site, the foal keeps in physical contact bumping the mare as they go along.
• Bonding is rapid at birth (within 2 hours) but foals can be fostered on to mares for up to 3-4 days. But the success of this depends on the nature of the mare and some mares will not have any other foal but her own. The skin of a dead foal is often tied on to a foster foal to fool the mare.
  

Early handling

• There are great benefits from handling and fondling foals soon after birth so they associate humans with positive experiences. They need to see you as part of their environment and not as a threat.
• But some horse experts say you can overdo this so care is needed. The danger is that the foal may end up being so friendly (and cocky) that it will be more difficult to dominate later. The behaviour developed early you’ll see later as foals are quick learners and remember.
• In the first few days just get the foal familiar with people.
• Experts suggest 3 weeks of age is early enough to start handling the foal and get this well established before 6 weeks of age.
• Start training by removing the foal from the mare for a few hours, speaking quietly and gently while encircling its neck with your arms. Release it only when it has relaxed and is comfortable with your actions.
• Fit a soft leather halter and lead the foal when the mare is led. The foal should never be driven. It must learn to come forward “off pressure” and this is taught with a rope around it’s rear end.
• Brush the foal, handle it often and introduce it to a variety of noises.
• From 3 months old, halter it regularly and lead it around vehicles, along farm tracks, etc, and get it used to different situations and especially noises.
• Later training is done on the long rein, i.e. "lunging" to build up fitness and to learn voice commands.
• Thoroughbred trainers reckon a total of 20 days training between 3 weeks and a 12 months old is enough. Training need not be repetitive and more than 3 days in a row is too much.
• Some suggest Lesson 1 at 3 weeks, Handled again at 10 weeks and then 3 training sessions before weaning which covers yearlings coming up to sale time. They need to accept being led, bridled, covered, loading on and off floats, standing on their own in a box and walking in and out of doorways.
• Weight bearing should be delayed till the horse is mature, usually after 2 years old.
• Take plenty of opportunity to introduce the young horse to different experiences.
• Correct mouthing is critical - use the correct bit to prevent soreness."Breaking" horses is out - "gentling" is in. There are many sources of information on this subject now.
  

Training principles

• Remember horses are a panic species - they respond to stress or fear by flight.
• They use speed, bucking and kicking and biting to escape threats. The principle of modern schooling or gentling is to prevent the horse escaping from handler so it learns to accept human contact as providing safety and security.
• Horses are very teachable and have a considerable capacity to learn.
• But work within the animal's repertoire of ability. A horse will cannot learn anything if it's incapable of doing it.
• Horses have a good memory but do hot have the ability to reason. They lack initiative but are not dumb. They rely heavily on innate behaviour.
• They cannot cope well in new and novel situations. They cannot solve problems that go beyond simple associations or limited choices.
• Recognise the temperament of the horse and this will dictate your approach. Your first lessons will indicate how the temperament is going to affect progress, and you may have to rethink certain actions.
• Horses are right or left handed showing side preferences and brain lateralisation.
• In training do not scare the horse as this will set up flight responses.
• Remember punishment only suppresses behaviour: it does not eliminate it.
• Punishment incorrectly given, or given to excess makes behaviour worse as the horse's sensitivity is reduced.
• "Reward training" is the simplest and best method, but reward must follow the correct and required action immediately. After a very short delay the association is lost.
• Rewards may include a pat on the neck, rest, food, or being able to see new and interesting things.
• In "gentling" a wild horse, handlers often start with a "carrot stick" which is a long stick with a leather thong on the end, which they use to rub the horse starting at the rear end. This imitates the feeling of mutual grooming, and the horse will enjoy this.
• Then the trainer moves up along the back to the shoulder, and finally to the head and nose. If you touch the head too early, all will be lost and you'll have to start again.
• Use "rewards" intermittently and do not reward for every correct response.
• Too much handling may lead to boredom and too little can produce a scared or reluctant horse.
• The trainer needs to be smarter than the horse. Problems mostly arise from what the trainer did wrong and not the animal.
• Break up the tasks to be learned into simple, basic steps and work from the known to the unknown.
• Always be consistent.
• The Monty Robert's principle (also attributed to many other trainers) is to drive the horse around a circular pen which is an alien territory for the horse, and then letting it come to you for security - when you are ready and want to let it come into your human space.
  

Animal behaviour and welfare: Pigs Part 2

PIG BEHAVIOUR BASICS: PART 2

Reproduction: Birth behaviour: Fostering

By Dr Clive Dalton


The female

• Puberty can be affected by breed, season of the year, and social environment (e.g. crowding) but especially by live weight.
• Mixing during transport sometimes triggers puberty where the transport stress is thought to trigger reproductive hormones.
• Contact with males will also stimulate first oestrus. However if exposure is too early or for too long, the gilts may become accustomed to the boar's presence and not react.
• To exploit this male effect, expose the gilt to the boar at about 160-175 days of age, and 60-90% of then should show oestrus within 10 days after exposure.
• Most breeds of gilts today come into oestrus between 170-220 days of age, when they have been moved from their finishing pens at around 90kg live weight.
• Weaning a litter will trigger the sow to come in oestrus. She usually cycles 4-5 days after removal of her litter.
• For best results, make sure the gilts are kept totally from within sight, smell or sound of the boar.
• Rearing gilts with contemporary male pen mates does not seem to advance their age of puberty.
• In general practice, gilts are mated and their third heat, when weighing about 118kg. However mating them at their second heat has economic advantages.
  

Signs of oestrus
Sows and gilts in oestrus show any combination of the following signs:

• Swollen and reddened vulva about 2-6 days beforehand.
• Mucous discharge from the vagina.
• Restlessness and a poor appetite.
• Females coming into heat may sniff the genital area of their pen mates.
• They may ride others and stand to be ridden.
• They will show a feature unique to pigs - the "stance reflex" where they arch their backs , stand rigidly when pushed from behind, and allow a person to sit astride them.
• Prick-eared breeds carry their ears erect and held back.
• Oestrus pigs make a characteristic grunt and seek other pigs while go around searching for a boar.
  

Mating

• The female pig assumes a major role in mating by searching for the male and converting social contact into sexual behaviour.
• "Standing heat" when the female will stand for copulation lasts around 48 hours (range of 38-60 hours). Some sows can stay on heat for up to 120 hours.
• The first heat is usually shorter and sows have longer receptive periods than gilts.
• Length of oestrus is also affected by breed, season and management system such as if sows are group our individual housed.
• Ovulation occurs during the second half of the oestrus period, so it's best for the boar to serve the sow twice - at the start and end of the standing heat period.
• Females not mated will cycle every 21 days (range of 19-24 days).
• Gestation in the modern hybrid pig kept intensively averages 115 days (range 108-122 days).
• The "standing reflex" of the sow where she will not move when weight is applied to her back increases as the oestrus period advances.
• The sow is stimulated by the boar and his pheromones from his body, especially his frothing mouth and the gelatinous exudates from his prepuce.
• The order of priority of these stimuli seems to be smell, sound, sight with physical contact last.
• Some sows show a preference for a particular boar and this can cause inconvenience in breeding programmes.
• When the boar is too large and heavy and risk damaging the sow (as mating can take a very long time), the female is best held in a crate where the boar's front legs rest on the sides of the crate to take some of his weight.
• Gilts may often only stand for a boar in the presence of another female in the mating pen, or with a familiar pig in an adjoining area. However, if these support pigs are nearing oestrus, they'll only distract the boar from the job in hand.
• It's a good idea to mate gilts to an old experienced boar and mate old sows with a young boar.
  

Female behaviour before birth

• Sows show great variation in their behaviour approaching birth. This depends mainly on age, previous experience, breed, strain and the husbandry system.
• Sows carrying a litter of more than 11 pigs will have a 5-day shorter gestation than those carrying average litters of 9-10 piglets.
• To avoid stressing the sow, she should be transferred to her farrowing quarters about a week before birth. This will allow them to settle in and reduce stress levels.
• Stressed sows (especially inexperienced ones) will have higher piglet mortality through overlaying and even attacking piglets.
• Heavily pregnant sows spend most of their time resting, sleeping and feeding.
• As gestation length varies widely, recognising the signs of approaching birth is very important, to ensure the welfare needs of the sow are met.
• Sows are nest builders - and they need to express this desire in intensive farming. A sow starts to nest build 3-7 hours before farrowing, and after giving birth she stays in the nest for 24 hours, nursing every 45 minutes.
  

Signs of birth

• The vulva swells and becomes redder, especially obvious in white skinned pigs about 4 days before birth (range 1-7 days). In black pigs you will only see the vulva starting to look like a swollen prune.
• The udder swells, becomes firm and colostrum can be obtained by gentle massage up to 24 hours before farrowing. Rubbing the front teats usually stimulates the sow to lie down.
• Increased restlessness. The sow gets up and lies down or changes side more frequently, twitches the tail, and chews the pen railings.
• She also urinates, defaecates and drinks more.
• The sow chews up the bedding (when provided) and makes the nest. She paws the ground, especially where no bedding is provided. This is a key sign.
• There will be a discharge of blood, birth fluid from the sow and green-brown faecal meconium pellets originating from the piglets.
• Respiration will increase from about 54 breaths/minute 24 - 12 hours before birth, to 90/min 12 - 4 hours before birth, reducing to 25/min at about 24 hours after farrowing. This together with intermittent low grunting and jaw chomping is common.
• Sow rectal temperatures rises from about 39 - 39.5 C four hours prior to farrowing. They then stay elevated (around 40 C) for up to 24 hours after farrowing.
  

Behaviour during birth

• During birth, the sow lies on one side, and in the intervals between piglets she may change sides, stand or sit in a dog-sitting posture. These movements risk crushing or overlaying the piglets.
• Studies showed that the average time to produce a whole litter averaging 11 piglets was 2 hours 53 minutes, or 15.3min/piglet.
• But these times vary greatly with a range from 3.6 min/piglet to 44.6 min/piglet.
• Normally 55-75% of piglets are born head first and 25-45% back legs first.
• Abdominal straining is more often seen before the birth of the first pig, and less common with the remainder.
• As the sow strains, her tail is often pulled back away from the vulva, and delivery of a piglet is often accompanied by vigorous tail swishing and expulsion of gas from the rectum.
• Paddling with the legs while lying down is common.
• The sow usually just lies still as each piglet is born, and she attracts them to her head end by special grunts. She doesn't stand up and lick them and chew their birth sack like other species. She also cannot turn to lick them as they are born like a bitch as she is not as flexible.
• After the piglets are born, the sow stands up and often urinates.
• Usually the foetal membranes start to be expelled during the birth phase and they may appear in two of three lumps. Most of it is shed after the last piglet is born.
• Four hours is normally needed to expel the complete afterbirth but this varies widely from 21 minutes to 12-13 hours.

Early sow and piglet behaviour after birth

Most milk is at the front teats

• About 70% of piglets are born with their umbilical cords still attached and attached to the foetal membranes still inside the sow's genital tract.
• The cord can be stretched considerably before breaking and this helps to prevent haemorrhage.
• It takes from 1 to 30 minutes for piglets to free themselves form their cords which became shrivelled within 4-5 hours after birth. The sow rarely chews the end of a piglet's cord.
• After a brief period of 5-10 seconds of not breathing, the piglet gives 5-6 gasps and a cough. This is followed by about 20 seconds of rapid shallow panting followed by regular rhythmic breathing.
• Most piglets attempt to stand within one minute of birth, and within two minutes they can stand freely and start searching for the teats, or anything that sticks out that feels like a teat - e.g. the point of the sow's vulva.
• There's a wide interval of 3 - 153 minutes/piglet (average of 10-15) between birth and the first milk intake. Piglets clearly vary enormously in their ability to find a teat although some are greatly restricted by the trailing cord.
• Nuzzling is a very important behaviour used in teat-seeking.
• Piglets show a very clear preference for the front teats of the sow, which generally have more milk than the rear ones.
  
• So the first-born piglets get the best (front) teats, which they claim and fight for until a suckling order is established.
• The front teats are longer with more space between them and they have a greater clearance above ground level than the rear teats, so the piglet can grip them more easily.
• Clearance generally declines up to teat number 6, and as the sow ages the udder becomes more pendulous and her ability to expose the bottom teats is reduced.
• The risks of piglets being kicked by the hind feet are also greater when suckling the rear teats. There is also a danger of being kicked by the front feet.
• So the front-suckling piglets grow faster and consequently maintain their social rank in the litter.
• Piglets sort out a hierarchy in the first few days, and a clear social order is established after a week.
• As milk letdown is very rapid (about 20 seconds) and occurs about once an hour, there's little opportunity for piglets to share teats. But if space allows, they may suckle more than one teat.
• Normally breeders select females with a minimum of 12 functional teats, and preferably 14-16. In older sows, wear and tear and mastitis may reduce the number of functional teats.
• Piglet suckling behaviour moves through the following stages:
• Jostling for position along the sow's belly to find the teat.
• Squealing while jostling.
• Nosing the udder.
• Slow sucking.
• Rapid sucking.
• Final slow sucking and udder nuzzling.
• The sow's grunting increases greatly up to the slow sucking stage which is a clear signal to the piglets that letdown is imminent. Letdown starts 25-35 seconds after this signal.
• The squeal of isolated, lost, or handled piglets will alert and stress the sow and she may interrupt her suckling behaviour to investigate. So don't pick up stray piglets during suckling time.
• Piglets sleep for about 15-16 minutes every hour.
• In the wild, the sow and her piglets join the herd after a week.
  

Fostering piglets

• When sows are farrowed separately but in batches, litter sizes can be adjusted by taking piglets from large litters and giving them to sows with plenty of milk and small litters.
• Care is needed as sows vary in their acceptance of foster piglets.
• Best results are obtained if piglets from both sows are the same age and under one week old before teat preferences have been established.
• For success- remove all the piglets from the sow that is going to be given the extras.
• Wait till they are really hungry and she is anxious to have them back.
• Rub the rear ends of the removed piglets over the anogenital area of the strangers to be added. The sow usually smells this area.
• Use the afterbirth for this job if it's still available.
• Then put them all with the sow and watch to make sure she lets them all suckle and accepts them.
• Fostering will probably disrupt the whole nursing process, because of renewed competition for teats. You'll see this in the uneven growth of the litter up to weaning.
• When sows farrow together in the open, piglets seem to mix freely from birth without any problems. The main concern for the farmer is to make sure that each sow has a similar number of piglets.
• Behaviour of dry sows It's important that dry sows have their diets carefully controlled to ensure their nutritional needs are carefully monitored and met.
• The need to have strict control over a sow's diet has led to the development of systems that restrict their movement, and these have large behavioural and welfare implications.
  

The systems used are:

• Sow stalls - the sow is held in a narrow stall, allowing her to move to and fro but not turn round. There is total environmental control.
• Sows tethered in stalls by a neck strap or a strap around her chest. She cannot turn round. There is total environmental control.
• Sows at pasture in groups with communal shelters.
• Sows at pasture in individual runs or tethered to individual kennels.
• Sows in groups of 6-10 in a yard with kennel-type shelter and individual feeders.
• There is an active national campaign in many countries (including New Zealand) to make sow stalls and tethering illegal because of the stress it causes the animals. This practice has been banned in some European countries.
• Sows in stalls and tethered sows tend to develop "bar biting" when they bite the front bars of the stall, and also show a "paddling" behaviour often seen by bored tethered animals.
• Research has shown that even in stalls, providing some straw gave some enrichment to their existence.
• The ultimate in luxury, (judged with an anthropomorphic view) is to keep dry sows in large yards in deep straw. But sows can have savage fights to establish a social order when housed loosely, and it adds greatly to costs of production. This is a classical example of what the domestic contract should provide.
  

The male

• In the wild or in extensive pig keeping systems, the male pig, (unlike males in other species) does not initiate sexual behaviour. He waits for initial signals from the female.
• Boars reach puberty about 6 months of age, but are generally not used for service till 7-8 months old. These ages can vary a lot depending on the feeding level.
• They start learning their courting behaviour and show elements of sexual behaviour while still suckling and as part of play with pen mates. They develop these behaviours even more if mixed with strangers.
• Boars reared in isolation are much slower to develop successful courting behaviour. Group reared boars are better than those reared in individual pens, and intensive stocking will encourage aggression as well as sexual behaviour.
• Boars reared intensively in homosexual groups maintain this relationships for many months after parting, and they can often show abnormal sexual behaviour.
• The boar's courting ritual includes:
• Chasing the sow.
• Nuzzling her head, flanks, shoulder and anogenital area.
• Occasional pushing or leaning on the sow to test her state.
• Drinking her urine.
• He urinates frequently.
• He grinds and chomps his teeth salivating and frothing at the mouth.
• This courting ritual has an important effect on improving the conception rate of the sows being mated. In outdoor pigs boars often have rings inserted in their noses to stop them rooting up the pasture. This affects their courting ritual when it comes to nuzzling the sow and causing a negative response.
• When the boar mounts, he rests his belly along the sow's back and grasps her with his forelegs. Inexperienced boars will head mount, side mount and dismount frequently before intromission (penis entering the vagina).
• Ejaculation occurs when the cork-screw penis of the boar locks in the sow's cervix. This can take considerable time - averaging about 7 minutes but it can last up to 25 minutes.
• The boar thrusts and rests many times and eventually ejaculates up to 500 ml of sperm. Other farm species produce a 5-15 ml ejaculate.
• 
  

Boar behaviour and handling

• Treat all boars with respect and treat them as individuals.
• Handle them carefully and de-tusk them every 6 months (with veterinary advice).
• Remove the front accessory claws to protect the sow from injury during mating (with veterinary advice).
• Don't overwork the boar - one boar to 20 sows is most common.
• Four services a week are plenty till the boar is 12 months old. Don't let him serve more than 6 times a week as this will lower his fertility and subsequent litter size from the sows mated.
• Too frequent use of a boar as a teaser to locate sows coming into heat, may frustrate him too much and he may not serve when needed.
• Mate young boars to old sows in peak oestrus, and old boars to gilts.
• Don't let young boars get injured during their early matings.
• After layoffs of longer than a month, libido may drop and a boar may need the stimulus of an old sow in peak oestrus that has already been served by another boar.
• Spreading some ejaculate from another boar along the sow's back will help to stimulate a boar.
• Take the sow on heat to the boar so he doesn't waste time investigating a new environment. Otherwise he'll waste time in an elaborate ritual of urinating, rubbing scent from his body on the walls, marking the territory with salivary foam and fight the sow to establish dominance.
• Boar pens should provide a good foothold for the boar but not so rough as it will cause foot problems.
• Boars should be kept within sight, sound and smell of sows. However this assumes the boar is the dominant animal in the herd. He may be considerably stressed with other boars near by, as in the wild each boar would be solitary.
• Boars get very large and need regular exercise to keep fit. It's a good idea to have a system where the boar walks daily to the sow's accommodation to help stimulate oestrus and identify sows on heat.
• Regular quiet handling by the stockperson is ideal, walking behind with a pig board for protection, and talking in quiet reassuring tones.
  

Boars and Artificial Insemination (AI)

• AI in pigs is now well established in commercial pig improvement and is a specialist operation.
• At AI centres boars are trained to mount dummy sows and serve into an artificial vagina as this is less complicated than using a live sow.
• Boars may be harder to train if they have mated sows first. But again this varies with the personality of the boar.
• Gentle, reassurance by the stockperson is the secret of success to get a good semen sample from the boar.
• Boars will show courting behaviour to the dummy by nuzzling its flank and rear end.
• Libido varies greatly between boars, and is related to frequency of use.
• Boars can be stimulated more by giving them false mounts, or by observing a collection from another boar.
• It's a good idea to allow the sow or gilt 10-20 minutes contact (through a pen) with a boar after insemination.
  

Behaviour of housed boars

• In less intensive systems where sows are kept in straw yards (and not in stalls), boars often run with them and few problems arise.
• If a boar is put in among a group of unfamiliar loose-housed sows, he will waste time investigating the environment and not checking for sows on heat.
• In intensive pig farming, the boar does not spend time in social contact with sows and opportunities to consort with females are decided by the human in charge.
• Here, sometimes the boar pens are arranged between pens of six loose-housed sows to achieve maximum physical presence of the male.
• In other systems, including where sows are tethered or in stalls, the boar is walked daily in front of them to test for oestrus.
  
• When boars walk behind stalled sows a boar may be confused by the fact that they are immobile and hence displaying an invitation to be mounted. This can be very time-wasting.
• It's well established that depriving boars and sows full opportunity to indulge in their full courting behaviour affects pregnancy and litter size.
  

Boar behaviour problems

• Serving into the rectum instead of the vagina can be a problem. Avoid this by supervising young boars in their early work to make sure they are aligned correctly.
• Extremes of heat may affect the boar's enthusiasm. Delay his work till evening.
• Masturbation by coiling the penis inside the diverticulum of the prepuce. Make sure the boar's penis has actually entered the sow and he is not masturbating.
• Boars that masturbate persistently should be culled although the prepuce can be surgically removed.
• Some boars behave normally up to the point of mounting and then squat down on the floor and ejaculate. Great care is needed to help these boars achieve success as they may persist in this habit.
• Aggression. Boars are always potentially dangerous and need to be handled with care. Nervous and aggressive boars should be culled. Some boars will show aggression with strangers but not with their regular handlers.
• When strange boars meet, they strut shoulder to shoulder, head raised and hair bristling along their backs. Deep grunts, jaw chomping and mouth frothing continues.
• In a fight, boars face each other with their shoulders in opposition and apply sideways pressure. They circle around, biting and slashing at each other with their tusks. They may charge each other with mouths wide open and bite. The loser turns and runs away squealing.
• Subsequently after a win, the winning dominant boar need only grunt to get submission. Newly-mixed boars fight less if they are both put in a strange environment.