In October, three rams (intact, male sheep), join the flock of ewes (female sheep), for a month so that the ewes become pregnant. It takes five months for a lamb to fully grow and develop inside a ewe, so almost all of the lambs are born in February and early March.
Ewes usually produce one to three lambs annually (gestation period of five months).
Lambs are born around 145 days (or about 4.5months) after the ewe falls pregnant. Lambing can start as early as December and go on to as late as June and a ewe can have up to four lambs at a time but mostly have one or two. There are two different breeds of sheep that we keep on the farm.
Gestation in sheep varies from 142 to 152 days with the average being 147 days. Just like people, individual pregnancies can vary, gestation periods of 138 to 159 days are not unheard of.
Sheep are short day/long night breeders meaning they breed late summer/early fall and consequently their lambs are born in the winter and spring. Second, during the winter, the pasture that sheep normally eat is dormant.
In many parts of Australia this means that ewes are mated in late summer and lamb in late winter or early spring, well after the break of the season. Under this management program, there should be plenty of pasture to satisfy the nutritional requirements of ewes in late pregnancy and early lactation.
Pregnant women who come into close contact with sheep during lambing or other farm animals that are giving birth may risk their own health, and that of their unborn child, from infections that such animals can carry.
Sheep fertility increases as daylight decreases, that is, after 22 December. Pregnancy rates from joining in January and February can be up to 20% better compared to a joining in October and November from ewes of equal condition. Out of season cycling can be enhanced by the use of teasers and the 'ram effect'.
Pregnancy is also called gestation. Since ewes gestate for only five months, it is possible for them to lamb more often than once per year. While annual lambing is most common, lambing intervals of 8 months are also realistic, especially in the tropics and with breeds that are less seasonal in their breeding habits.
Gestation: Average gestation length or length of pregnancy for sheep varies from 144 to 151 days (about 147 days; figure 11).
Signs of impending lambing
About 10 days before the ewe will lamb, the teats begin to feel firm and full of colostrum. Between then and lambing, the lips of the vulva slacken and become slightly swollen. In the last hours before lambing, many ewes will separate from the flock.
Seasonality ensures lambs are born at an optimal time, in the spring, when grazing quality increases to support lactation.
Most sheep have a breeding season (tupping) in the autumn, though some are able to breed year-round.
Ewes that lamb on the hill usually give birth at dusk or dawn, this is natural instinct to lamb in semi-darkness to avoid predators such as the Bonxie and Ravens. By lambing at night this timing gives the lambs a chance to get to their feet.
My advice is to leave the ram with the ewes after the official breeding season has ended, at least up to lambing. He will graze with them and in the winter, he will eat hay with them. No need to add extra work to house a ram separately at that time.
A ram that is kept with ewes is likely to be overfed, as a ram does not require as concentrated a diet as pregnant and lactating ewes. Some rams may be too aggressive to be kept with pregnant ewes. In less developed countries, they have a created an "apron" to prevent rams from impregnating ewes during comingling.
If ewes lamb during the breeding season the first postpartum ovulation can be within 20 days, although this will not generally be a fertile cycle. As well as the season, other factors such as suckling by lambs, breed, nutrition, and environmental temperature may also have an effect.
If there's a twin, the ewe will continue getting up and lying down while talking to the first lamb to keep it near her. The 2nd lamb may be birthed before the 1st lamb nurses. The lamb will begin to nurse and may headbutt the udder. If there's a twin, the ewe may clean it while the 1st lamb in nursing.
In many other animal species males will pair up with males and females with females under certain circumstances, but with sheep it's a life-long propensity. 4. The upper lip of a sheep has a pronounced groove dividing the left and right side, called a philtrum.
Joining rams and ewes for longer than 3 months is not advisable as lambing will interfere with other management activities such as shearing and crutching.
Lambing Kit
Most ewes will lamb within an hour of their water breaking, therefore ewes must be checked at least once per hour. Any ewe that has not made progress within 30 minutes after her water has broken should be laid down and checked.
Whilst the recommended lamb weaning age is 12 to 14 weeks from the start of lambing, lambs can be weaned at 8 to 10 weeks or even earlier if appropriately fed and managed.
Ewes may reject their lambs for numerous reasons, including the mother being injured or sick, a difficult or traumatic birth, sickness in the lamb, the lamb having an inability to nurse or the mother lacking enough or any milk, too many lambs being born, or the lamb being unable to keep up with the flock while in the ...
A pregnant sheep has no specific terminology attached to it, so would simply be a pregnant ewe. A female sheep can be referred to as a ewe or a gimmer. A female sheep that has given birth is a yow, and a female sheep that is too old for breeding is known as a cull yow.
Ewes establish a selective bond with their offspring after birth, during a sensitive period of maternal responsiveness1. Accordingly, ewes only display maternal care toward the offspring, whose odour was identified during that period, thus rejecting lambs not of their own.