November 24, 2008

Animal behaviour and welfare: Goats Part 3


Reproduction: Birth, survival

By Dr Clive Dalton

Finding the teat is critical for survival -especially
with multiple births and in bad weather

The female (Doe or Nanny)
  • Goats are seasonal breeders coming into heat in autumn as daylight declines.
  • They reach maturity at about 5-6 months old but well-reared milking-breed kids can show heat earlier (4 months) so they have to be watched to avoid too-early mating.
  • Once the doe starts cycling she will come on heat every 17 days like sheep, and stays on heat for about a day. But these times can vary greatly.
  • Feral does seem to prefer old mature high-ranking bucks in preference to young ones. But this may be because the old bucks are more aggressive and chase the young ones away.
Signs of oestrus:
  • Vocalisation - especially if a lone goat.
  • Urinating a lot - crouched with rear legs set open.
  • Tail fanning.
  • Showing aggression to other goats and biting them in the milking bail.
  • Some mounting of other goats - or their friendly owner!
  • The doe is stimulated to cycle and ovulate by the smell of the buck.
  • Pregnancy in goats is about 5 months like sheep.
  • Goats can show pseudo-pregnancy and it can be a problem mainly in milking herds.
The male (Buck or Billy)
  • Male goats have a thick beard but so do females so the beard is not stimulated by hormones.
  • Male goats reach puberty about 4-5 months old, but you should not assume that younger males will not be fertile.
  • Mature males show a definite "rut" period and the first sign of it is when they start to smell strongly. This smell is made worse for humans (and better for does) by the goat spreading a thin jet or urine from his erect penis along the belly, chest and on to his beard.
  • This is called "enurination" and is seen regularly where bucks are tethered, or when kept separate from does waiting for mating to start. Bucks, especially male goatlings run in groups, can use up so much energy in this activity that it impairs their efficiency when joined with does.
  • Bucks twist themselves around so they can get their penis into their mouth where the urine stimulates a Flehmen reaction. They will often even masturbate and ejaculate on their bellies and beards - all adding to their aroma which stimulates heat and ovulation in the does.
  • Does often are very interested in this behaviour and stand and watch attentively.
  • Before mounting, the buck sniffs the doe's side and genital area. He chases her making "gobbling" sounds with his mouth, and flicking his tongue in and out like a ram does.
  • If the doe urinates he tastes it and gives a Flehmen response. He may have a false mount or two and then a proper mount with ejaculation when he thrusts forward and leaps off the ground.
  • Following ejaculation - he may lick his penis, and show a Flehmen response again.
Doe behaviour at birth
  • Just before birth a doe is often more fretful and nervous.
  • Feral goats will separate from the main group and find a birth site in a quiet sheltered spot but milking goats in a herd may not have space to do this.
  • Near birth the doe will have "bagged up" and may show a mucous discharge from the vulva.
  • Udder swelling will be much more obvious in milking goats than in feral goats with smaller udders.
  • If kept indoors, the doe will paw the bedding and try to make a birth site.
  • Birth should take about an hour but problems can arise with multiple births as in sheep.
  • The doe should get up quickly and turn to chew the membranes and lick the kids. The kicking of the kids usually bursts any membranes covering them, but you can get deaths from a piece of membrane left on the nose.
  • Afterbirths are passed soon after birth but may be delayed for up to four hours. There seem to be fewer problems with retained foetal membranes in goats and sheep than in cattle.
  • The doe recognises its kid first by smell and then by both sound and sight.
  • Fostering alien kids to does has the same problems as in sheep, and the same tricks are needed to fool the doe. (See sheep behaviour).
Kids behaviour at birth
  • Once on their feet, kids should start their teat-seeking behaviour.
  • They nuzzle the doe's side to find some warm bare skin and hopefully with a teat.
  • Good mothers will stand still and encourage the kid to do this by nuzzling the kids rear end, rather than keep turning head-on to lick it.
  • Survival depends on getting enough colostrum within the first hours after birth.
  • Kids do not follow their mothers all the time like lambs so have fewer suckling periods when the doe goes back to feed them.
  • Cross fostering lambs on goats and vice versa highlights this behavioural difference, with lambs on goats growing faster than their kid mate as they followed the doe and suckle more. The ewe with a kid kept often loses it as the kid goes to lie on its own.
  • In the first few weeks after bonding is strong, a doe will go back to its hiding kid and feed it 4-5 times a day. This intense hiding behaviour lasts from 3days to several weeks till the kids are eating pasture when they follow their dams more.
  • Dairy kids are kept in mobs and fed on milk replacer diets where they can feed ad lib, along with supplemented hay and meal.
  • Disturbance at birth will cause bonding problems, and the doe may take off leaving a twin behind.
  • There is a high death rate among feral kids and you regularly see a doe with twins at birth with a single a week or so after birth.
  • With farmed goats, providing shelter is very important for does and kids during the first weeks of life.
  • During the first weeks, kids will start playing together but will still stay close to their dams. They often climb on their parents' backs and seem to be tolerated.
  • Kids start to nibble grass by 3 weeks of age, and after 8-9 weeks are very effective ruminants.
Twins are more likely to die in cold wet weather than singles if they
don't find the teat. This pair died as a result of a difficult birth.

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