November 24, 2008

Animal behaviour and welfare: Cattle Part 4

CATTLE BEHAVIOUR BASICS: PART 4

Calf rearing: Fostering: Housing: Bobby calf; Premature calves

By Dr Clive Dalton



The young calf
  • Calves are very delicate animals; they are not robust small cows.
  • Their rearing system can have a big effect on subsequent behaviour.
  • It's vital that calf gets 2 Litres of colostrum (from dam or other newly-calved cow) before 6 hours old). Keep some colostrum in the freezer for emergencies.
  • There is a wide range of calf rearing systems where the main aim is to give the calf a good start and encourage it to become a ruminant.
  • A calf is born with a large abomasum (gastric stomach) and offering fibrous feed from birth (hay and meal) will encourage its rumen to grow and develop. This reduces the need for milk and lowers feeding costs.

The large gastric stomach (abomasum) of a milk-fed calf. Note the very small rumen on the left of the picture.

When do calves become ruminants?
Calves start to chew hay and straw if provided in their pen a few days after birth, and if offered concentrates and good quality pasture they will be fully-functional ruminants by 3-4 weeks of age.


Four-week-old calves offered good leafy pasture


Getting calves to drink
  • Most calves are now reared using communal systems with a "calfeteria" allowing them individual feeding but run in a group environment.
  • Initially a calf wants to push upwards when sucking and bunts to stimulate milk flow from the udder.
  • To get the calf to suck on a “calfeteria”, let it suck your fingers and then lead it to teat to suck. Hold its head gently on the teat for a few seconds once on the teat.
Calf rearer using a single-teat feeder (standing on rail) to teach calf to suck from a rubber teat, then taking it to the Calfeteria to suck from one of its teats.
  • If you use a bucket, let the calf suck your fingers and then press its head down into the bucket while sucking. Withdraw your fingers and keep its head in bucket. Initially it will gulp milk and choke - let it up for air!
Feeding calves from buckets once they have been taught to change from sucking (with head up) to drinking (with head down). This can take time and be frustrating for the calf rearer.

  • Calves often want to continue suckling after their milk supply is finished. This "suckling reflex" encourages them to suck the ears, navels and teats of other calves. It can lead to problems so this vice must be discouraged.
  • Calves that suck other's teats may continue into adulthood and it can cause problems. How to stop it?
  • Make the calves work harder for their feed so the sucking urge runs out.
  • Tie them up after sucking till their mouths are dry.
  • Separate out the culprits as they will teach others.
  • Fit irritant device in the nose of sucker so others won't let them suck.
  • Provide dry palatable feed immediately after sucking.
  • A combination of wet and cold is the biggest killer of young calves or can be the reason for poor performance. Calves at pasture need shelter, either natural or artificial.
Fostering new calves on to nurse cows
  • Cows vary in their maternal instinct. If a cow is too determined not to take strange calves, don't bother with her as it will cost you too much time. She'll associate you with the calf and will soon learn not let it suck unless you are there or she is bailed up.
  • The easiest way is to have the strange calf to be fostered ready at birth, and cover it with the birth fluids from the cow. Make sure she licks and mothers both calves.
  • You can try the same trick using odours such as neatsfoot oil or perfume. They don't work as well, and certainly not as well as birth fluid. The oil will get the cow to at least lick the calf, and this may trigger maternal acceptance. The perfume may put her off. Cows' preferences in perfume are not known!
  • Remove her own calf at birth before she has smelled and licked it, and introduce the fostered calf (or calves) after rubbing them in birth fluids (collected in a bucket) or with the afterbirth.
  • Blindfold the cow while the alien calves are introduced to her but she may not like this idea.
  • Remove the cow's own calf after 2-3 days, and bail her up tight with some good strong alien hungry calves. Make sure she cannot get round to bunt them (dehorn the cow) and that she cannot kick them too violently.
  • While letting her suckle her own calf, introduce the alien calf and teach it to suck through her back legs (the cow's blind spot). It will end up with a dung cap but at least it will be well fed!
  • Put leather dog collars on the cow's own calf and the alien one, and tie them together with a short length of chain containing a swivel. When the cow lets her own calf suck, the foster one will be close too, and the cow will hopefully get used to having both suckling at the same time.
  • If her own calf has died, skin the dead calf and tie it over the new calf until she lets it suckle. This will vary from a day or so up to a week or more, when the skin starts to stink! This is mainly used in a beef herd where getting a cow in daily to suckle a calf is not practical.
  • A vaginal douche with iodine solution (5ml of veterinary iodine in 250ml water) used to be practiced and was sufficient to treat three cows. It seems to cause irritation of the vagina and stimulates straining and maternal instincts. It is not a welfare-friendly method so consult a veterinarian before use.
Calf housing

Good calf housing with clean dry bedding, sunshine in the shed, plenty
of feed and water points, and a quiet stress-free environment.
  • In New Zealand calves are only housed for a very short time, as we want them to get outside and start grazing as early as possible to reduce costs.
  • Housed calves often suck the sides of the building and woodwork so it's important to make sure they cannot reach treated timber, old doors or the sides of the shed painted with old lead paint, and they cannot eat treated (arsenic) shavings used for bedding.
  • Veal calves are kept in narrow crates in Europe but these are banned in UK and not used in NZ.
  • The bobby calf pen is the main concern in NZ, but there are clear size specifications for this in the Welfare Code for Bobby Calves.
The “bobby“ calf
  • The bobby calf trade is a very important source of export income for dairy farmers.
  • Bobby calves go for high quality veal to the US.
  • The calf's stomach (vel) is used for the enzyme rennet used in the cheese industry.
  • The MAF Bobby Calf Code of Welfare states that a "bobby calf" must:
  • Be at least four days old.
  • Have a dry withered navel.
  • Have worn feet pads proving it has stood up and walked.
  • Be healthy and free of disease and injury.
  • Have been fed only on milk.
  • Calf pens have now been removed from the roadside to inside the farm gate to prevent welfare concerns of those who pass by, especially tourists.
  • Bruising, skin damage and navel infection are the main causes of wastage.
  • Calves must be electrically stunned and then stuck (bled) immediately after stunning.
  • The main concern is transport. The code says they must reach destination within 8 hours of collection. This is often not achieved as meat works move them around to keep killing chains in business.
Premature calves for blood harvesting
  • These are calves born before time or induced (aborted).
  • Their blood is used for the special pharmaceutical export market.
  • They have not had colostrum and so have not ingested any antibodies.
  • There are very tight regulations on their transport, welfare and slaughter.

Weaning
  • Weaning is usually defined as the time when you stop feeding milk and this is best determined by weight rather than by age.
  • Dairy calves are generally weaned when they are eating at least 1kg of meal/head/day.
  • Single-suckled beef calves are weaned in autumn when they are generally about 6 months old. Here they do wean more on age than weight as it's a seasonal practice.
  • Weaning is a gradual process in dairy calves as they move from milk to meal, then from indoor pens to outside an on to pasture.
  • In suckling beef calves, weaning is much more of a shock as it all happens on one day. It's usually accompanied by a few days of roaring by both calf and cow trying to get back together.
  • It's a good idea to separate them by 2-3 well-fenced paddocks away from the house, as the stress and noise can go on for up to a week.

No comments:

Post a Comment