January 25, 2009

Cattle farm husbandry –breeds and breeding

Cattle, farming, husbandry, breeds, breeding, methods, stud breeding, performance recording, using records, crossbreeding, inbreeding, linebreeding, interbreeding, grading up, future developments in breeding

By Dr Clive Dalton

What breed are these? Does it matter?

Who to believe?
If you believed what some enthusiasts say about their particular breed of cattle, and the promotional advertising and literature produced by breed organisations, then you’d have to conclude that every breed was “perfect”.

You’d hear and read that each breed had the best growth rate, best maternal traits, easiest calving, best survival, best temperament, ideal muscling, high lean meat content with low fat – and that’s only the start!

So why then do we currently have over 30 pure breeds of cattle in New Zealand? The answer is because we don’t just keep cattle to make money – we humans keep animals because we like the look of them in the front paddock, and many other reasons not related to paying the bills. And fortunately there is no law against this!

So if you have not chosen a breed, get all the information you can and talk to as many people as possible – both for and against the breed you have considered. Go and see their properties, especially in winter when feed is short to see the state of the paddocks. Large cattle “pug” paddocks more in wet weather than lighter breeds. Here’s a list of breeds currently available in New Zealand and where they came from:

Breeds in New Zealand

British beef breeds
  • Angus (formerly the Aberdeen Angus)
  • Hereford – both Polled and Horned (Separate Breed Associations)
  • Beef Shorthorn
  • Galloway – black, dun and belted
  • Highland
  • Luing – from Beef Shorthorn x Highland

British dual-purpose breeds
These breeds were combined beef and dairy breeds in UK, but are used only for beef in New Zealand.
  • South Devon
  • Red Devon
  • Red Poll
  • Welsh Black
  • Sussex (now classed as rare)
  • Lincoln Red (now classed as rare)
  • Dexter

European breeds
These large, heavy, well-muscled breeds arrived in New Zealand in the 1970s to produce meat from the Friesian dairy cows, and are now established as purebred beef breeds. They were developed in Europe for meat, milk and draft.
  • Simmental (Swiss)
  • Charolais (French)
  • Limousin (French)
  • Salers (French)
  • Maine-Anjou (French)
  • Blond d’ Aquitaine (French)
  • Gelbvieh (German)
  • Meuse Rhine Issel (MRI) (Dutch)
  • Marchigiana (Italian)
  • Romagnola (Italian)
  • Chianina (Italian)
  • Piedmontese (Italian)
  • Belgian Blue (Belgian)
  • Pinzgauer (Austrian)
  • Aubrac (France)

Other breeds
  • Murray Grey from Australia (beef)
  • Braham from USA via Australia (beef)
  • Brangus from USA via Australia (beef)
  • Sahiwal from India via Australia (beef)
  • Santa Gertrudis from USA via Australia (beef)
  • Texas Longhorn from USA via Australia (beef)
  • Wagyu from Japan (beef)
  • Taurindicus brand of Sahiwal x Holstein Friesian (tropical dairy)
  • Brown Swiss from Switzerland (beef and dairy)
  • Australian Lowline (small Angus) (beef)
  • Miniature Hereford (small Hereford) (beef)
  • Rissington Breedline (Composite)
All breed organisations are listed in NZ Contacts in Agriculture (see further reading).

Stud Breeding
  • Stud breeders keep “purebred” cattle and sell “stud stock”. Their main aim is to maintain and improve their breed for future generations.
  • Stud animals are “registered” in the breed organisation’s stud book where animals are described as being “pedigree stock” because the names and numbers of their ancestors have been recorded in the stud book.
  • Pedigrees may go back many generations and you can obtain a standard 5-generation pedigree from breeders who produce them themselves or they can obtain copies from their breed organisaton.
  • Breed organisations also provide general information on the breed, and breeder’s contacts for advice as well as those who have surplus stock for sale.

How to start a stud
  • Contact the breed organisation to find out all you can about the breed to make sure the animals will fit your farming situation. Be aware of the difference between facts and promotional hype.
  • Ask the breed organisation for a list of breeders you can talk to, visit their farms and see what surplus stock they have for sale.
  • Watch your language here and don’t ask if they have any “culls” for sale. Ask for stock “surplus to requirements”!
  • Stock and station companies also have specialist “stud stock agents” who will source stock for you. You don’t pay commission on purchases but they will expect your business when you have stock to sell. Commission is about double what it is for commercial stock.
  • Find out from the breed organisation what semen is available for the breed, because it would be wise to avoid having to buy a bull in the first instance.
  • Buy the best breeding females you can afford.
  • Ask the vendor why these animals are surplus to his/her needs – in other words find out if they are genuine animals surplus to requirements, or culls with health or reproductive problems.
  • Key point: A reputable breeder or agent will never sell you culls, and they will take any defective stock back or replace them. Genuine breeders are very proud of their reputation as breeding is a long-term business, and they may want your continued business.
Other thoughts on stud breeding
  • Your main income as a stud breeder will come from selling bulls, usually as 2-year-olds.
  • Don’t expect to grow an automatic and immediate reputation as a stud breeder – even if you have purchased top animals from a noted stud.
  • You will have to serve your time in the business and should initially accept a role as a “multiplier” passing on the genes of the top stud to commercial breeders.
  • Don’t think other stud breeders will buy from you until your worth as a breeder has been judged. This title is as much about public relations as genetics.
  • Exhibiting your stock at shows is part of this reputation building – so be prepared for the expense, entertainment and frustration of this.
  • Remember to call yourself the “stud principal” and not just the owner. This is used in the USA and Australia but is not very common here yet. It certainly sounds important!
  • The aim of studs is to improve the breed, but most have too few cows to bring about any significant genetic gain.
  • Key point: Geneticists reckon that you need at least 100 cows to be able to do any serious genetic improvement through selection and culling.
  • For example from the 48 bull calves that on average will be born from a 100 stud cows, you might end up with 15 reasonable two-year-old bulls to sell.
  • If you had 20 cows you might have 4-5 decent bulls to sell. Certainly don’t expect to sell every bull calf born as a top 2-year-old sire!

Performance Recording
  • In the old days you didn’t worry about records, especially for traits like weight and fertility, and breed organisations did not record these in their stud books.
  • Breeders made decisions on which animals to keep and which to cull on the basis of “eye appraisal” or what they could see on the outside, together with detailed knowledge of the ancestors in the pedigrees.
  • Today, things are now very different and studs can provide extensive performance records so you can buy on genetic potential and not just looks. But it’s up to you to ask for the records and find out what they all mean.
  • The stud breeder is the best person to explain these to you – and then you can judge how serious he/she takes them in their breeding policy. A stud stock agent will also help you understand the paper work and how to use it along with a physical inspection of the animal.
  • Key point: If you are not happy with the answers you receive - keep on asking questions. You are allowed to show your ignorance – they are not!

Using records when buying
  • When trying to make a decision about different traits on an animal, look at the EBVs or Estimated Breeding Values. They are mathematical “predictions” of the performance of the animal’s genetic potential when it becomes a parent. Note these can only be a prediction and not a guarantee!
  • So you’ll see an EBV for a wide range of traits from birth weight to 400-day weight, and indeed the large number of them can be confusing when you are deciding which ones you’ll need for your particular herd. Here again, ask the breeder or stock agent for help.
  • For example is you were buying a bull, you would look for a negative (below herd average) EBV for birth weight and a negative EBV for gestation length and a positive (above herd average) EBV for calving ease. This would aim to improve your herd by having cows that had shorter gestations producing small calves at birth and no calving problems.
  • If you want to work out the EBV of an offspring, then add the sire and dam’s EBV together and divide by two. So for 400 day weight if the sire’s EBV is +40 and the dam’s +20, the offspring will be +40kg heavier at 400 days than offspring from parents with EBVs of zero.
  • Then there are all the EBVs for weights at different ages such as 200, 400 and 600 days of age. Can you see how it would be easy to get confused?
  • To make things easier, and improve general understanding of all these figures, some of the important EBVs have been put together into “Indexes” to predict the value in dollars what the animal will earn through its offspring.
  • Remember that these are not real dollars – the dollars are only a handy value to use as a prediction. So use performance records when you buy stock and emphasise them when you are selling.
  • Note that the physical features of an animal you want to buy are still important, and breeders are very concerned about what they call “structural soundness”.
  • These are traits like feet, legs, reproductive organs, correct walking and correct jaws, and a defect in any of these could not be compensated for by top records on paper.
  • If you were just farming commercially and not showing cattle, then you need not be concerned about traits like colour oddities on the belly or the tail twitch.
  • Key Point: Remember another very important principle of genetics which is that the more traits you select for the slower the rate of gain in any one of them. So keep your objectives to a minimum and make sure they are money makers.

  • If you don’t want to run purebred cattle, then you can farm crossbreds where the breed of bull used is different to the breed of the cow.
  • The first time you do this you get a “first cross” (or F1) calf, and then if you keep crossing your cows with different breeds of bull, you’ll end up with a mixture that your pure-breeding friends will refer to as “mongrels”.
  • In modern parlance you can tell them you have generated a “gene pool” and are breeding a “composite”!
  • In dairy cattle the Friesian bull x Jersey cow is a much respected animal expressing “hybrid vigour” or heterosis.
  • Watch this definition of hybrid vigour, as it means an improved performance above the average of both parents, and not necessarily an improvement over either or both parents’ performance. This is regularly misunderstood.
  • Many dairy farmers with Holstein Friesian crossbred cows have a very simple programme. When the offspring start to look like Friesians they are mated to Jersey bulls, and when they look too much like a Jersey they are mated to Friesian bulls.
  • This has been so popular that now bulls of this crossbred are available through AI and are being talked of as a breed – the “Kiwi cow”.
  • A third sire breed can be incorporated in this programme so the first mating would be Jersey on Friesian, and on that crossbred animal when it came to breeding age it would be mated to Ayrshire bulls.
  • This is called 3-way crossing and can be very successful in merging the traits of three breeds.
  • In beef cattle don’t get any more involved than a 3-way and send all their offspring to slaughter to keep things simple. The theory says that by the third cross most of the initial hybrid vigour has run out.
  • If you did keep adding sire breeds on to the female crossbred offspring from the crossbred dams and using them in a set rotation, then you could explain to skeptics that you were using the concept of “rotational crossbreeding” designed to retain hybrid vigour.
  • The theory behind crossbreeding is that it increases genetic variation and combines traits to give you more genetic variation (due to genes) and hence scope for improvement by selection.
  • If you wanted to make a new breed, you’d make a mix of breeds considered to have useful traits, and start selecting and culling on performance in the environment they had to live under. This will concentrate the good genes you wanted.
  • That’s the way the Luing cattle breed was formed from Highland and Beef Shorthorn, and Santa Gertrudis from Brahman and Shorthorn, the Brangus from Brahman and Angus.
  • The interesting thing is that the “purebreds” many breeders revere so much today were all formed like this – they were the crossbreds of yesteryear.

  • Note - this is NOT inbreeding!
  • You may see the term “interbreeding” used when new breeds are being formed.
  • It’s got nothing to do with “inbreeding”.
  • Interbreeding is where you get to such a mixed gene pool by crossing that you stop worrying about it, and just keep on selecting males and females as parents on performance out of the mix.
  • This was the principle used by Thomas Bakewell, the “Great Improver” of farm livestock in the 1700s, where all he did was to “mate the best to the best”!
  • It still works today as long as you define “best” on the basis of performance, functional traits and not just cosmetic looks.
  • The New Zealand Huntaway dog is the classical example. It’s a real mongrel mix if you like but it’s the best dog in the world for it’s job. Huntaways were bred to work and nobody cared what they looked like.
  • If they didn’t work they made an early exit with no contribution to the gene pool and fortunately nobody kept them as pets to confuse things.
Inbreeding and linebreeding
  • In crossbreeding, cattle are mated which are not related, so you end up producing more genetic variation in the herd.
  • In direct contrast, inbreeding is where you mate animals that are related, i.e. have common ancestors somewhere in their pedigree. It’s sometimes called “close breeding”.
  • If related animals are mated, their offspring will have more of their parent’s genes in common – whether they are good genes or bad ones so genetic variation will decrease.
  • If you mate animals that are very closely related like sons back on mothers or sires on daughters, you’ll increase relationships (called homozygosity) very rapidly indeed, and this is called intense inbreeding.
  • If you do it more slowly when mating cousins, then homozygosity will build up more slowly and this is called “linebreeding”.
  • So the difference between inbreeding and linebreeding is simply how fast you proceed towards homozygosity, or the state where everyone had the same genes like you would get in clones.
  • You don’t get very far with inbreeding in cattle compared to what’s possible in plants as they usually become infertile or show very poor survival and die out.
  • As inbreeding starts to build up, you see minor defects appearing like undershot jaws, extra limbs or odd colours. But then as it increases further, “inbreeding depression” takes hold and you find weak offspring at birth, poor survival and poor growth. If the animals get to breeding age they have low fertility.
  • So the general rule is to change a bull before he has to mate his own daughters. In minority breeds it may not be possible to find a totally unrelated bull, so a rise in the inbreeding level is inevitable.
  • The inbreeding level is under constant scrutiny in dairy herds where today’s top bulls used over a large number of cows through AI, inevitably are the sires of the next crop of top bulls. AI organisations now have programmes to check relationships before the cow is inseminated.

Grading up
This is using crossbreeding to change from one breed to another. Here’s the usual process:
  • You start off with “foundation” animals of one breed or type. Usually there are no rules about what they look like, but it would pay to check if they need to be inspected and approved by the breed organisation of your choice.
  • Mate them with a purebred pedigree registered bull of the breed you want to change to, and this will produce F1 offspring. These will have 1/2 the genes of the new breed you want.
  • Mate these F1 females to a purebred pedigree bull again. They may need to be approved by an inspector from the breed society or association before proceeding to breed from them so check this out.
  • This produces the F2 that have 3/4 of the new breed.
  • Carry on mating the females born each generation to produce 7/8 and 15/16 offspring.
  • Some breed organisations will allow you to register 7/8 as “purebreds” but others only accept the next generation of 15/16.
  • This can be a very long process as only half the calves born each generation are females, and along with losses, some animals may not turn out to be acceptable (if inspection is mandatory).
  • It’s a funny thing that when grading up and you want heifer calves, how you seem to have endless runs of bull calves confounding the laws of nature.
  • In frustration breeders often question and blame the use of frozen semen for this, inferring that freezing has killed all the male-determining sperm.
  • Some pedigree breeders over the years have always been concerned that these newly graded-up purebreds could have introduced some “rogue” genes that have had bad effects on the breed. Some geneticists consider this to have been an asset to the breed by introducing genetic variation to allow greater selection potential.
Future developments in cattle
Genetic research today is heavily involved in identifying specific genes to improve traits like meat quality, tenderness, feed conversion efficiency, reproduction and disease resistance.

Advances in reproductive technology are the way these genes will be multiplied and made commercially available. Here’s a brief description of some of these techniques which are at varying stages of commercial availability:
  • MOET: “Multiple ovulation and embryo transfer” - sometimes called “super-ovulation and embryo flushing”. The cow is stimulated to produce many more eggs (oocytes) than normal at ovulation, then after insemination the embryos are flushed from the uterus through the vagina. Very large numbers of embryos can be harvested but five good quality ones per flush is a realistic average. These can be implanted in to other cows treated with hormones to be at the correct stage of their cycle, or frozen for later use or sale.
  • TVR: “Trans-vaginal recovery” – also called “ovum pickup”. In TVR oocytes are taken directly from the cow’s ovaries and the operation can be performed on yearlings or cows soon after calving or even in early pregnancy. Oocytes can also be taken from cows immediately after death; this is called GR or “genetic rescue” and is an ideal way of exploiting the genes of former top-performing cows in the herd.
  • IVP: “In vitro production” is where embryos are grown in the laboratory and there are three stages to this. First is IVM or “in vitro maturation”, then IVF or “in vitro fertilisation” and lastly IVC or “in vitro culture” – the whole process taking eight days.
  • Sexed semen: This has been possible for some years (currently with 90% accuracy), but is not commercially available on a large scale yet. It’s ideal for an AI programme to breed females for replacements or males for beef.
  • Embryo genotyping: Here the genotype of the embryo can be checked before implantation. The aim is to avoid spreading defective genes and multiplying good genes – once they have been found. Currently there are only a few available but as the cow genome or genetic map is researched, more will be commercially available.
  • Embryo multiplication: This is the process of taking one embryo and dividing it up at the appropriate (early) stage to produce identical twins, triplets, quads – or more.
  • JIVET: “Juvenile in vitro embryo transfer”. This is where IVP is done on calves (one month old) and when perfected will be a powerful tool to reduce generation interval which is limited by the age of normal puberty. Currently results are not commercially satisfactory.
  • Clones: Clones are totally identical in their genetic makeup and have been produced from body cells as opposed to sperm or eggs. Dolly the sheep for example was produced from a cell from her mother’s udder. Cattle have been cloned and used commercially in AI to produce two bulls to meet a large demand for semen that one bull could not supply.
  • Short-gestation semen: This is semen from bulls that have been selected to produce calves which are born less than the average 280 days gestation. Bulls currently available have Breeding Values ranging from BV -6.6 to BV -8.4. So if you mate one of these bulls to an average cow, he will shorten the gestation of the calf produced by half his BV. If you mate the bull to a cow which has a Short Gestation BV, the calf’s gestation will be the average of both BVs.
  • Freeze-dried semen: When this is commercially available, it will make transport and delivery of semen easier.
  • Organic semen. This is semen processed to meet the certification standards required for Organic Certification.

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.

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