Botswana
Sheep farming made easy Part 2:
Adequate feeding of ewes during late pregnancy and lambing is critical for lamb survival. Photo: Pixaby.com.
Production cycles and reproduction management R
eproduction is one of the most important factors which determine profitability when farming with sheep. The reproductive rate varies by farm, production system, and geographic areas. An ewe's production year can be divided into four distinct critical periods. The ewe is mated during a mating season of about three to six weeks, followed by a gestation period of 153 days (depending on breed) and a lactation period of up to 120 days.
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In-phase vs accelerated lambing In-phase lambing systems is when each ewe lambs only once a year. The group is divided into two so that the ewes from different groups will lamb at different times of the year. Accelerated lambing is when ewes lamb more frequently than once a year. The purpose of accelerated lambing systems is to reduce fixed costs, produce a more uniform supply of lamb throughout the year, and increase profitability.
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Test rams for fertility. If only a few rams are used, they must be fertile. Rams must be healthy at breeding time. The maximum age at which rams can be used for mating is 7 to 8 years. Old rams cannot follow ewes for long distances. Ensure that the rams are in a good condition at breeding time. They must not be overfat because then they become lazy. When animals must walk long distances during the breeding season, rams must be bought in good time so that they can adapt to the environment. Do not release expensive, newly bought rams in areas where there are large numbers of poisonous plants.
Factors that influence the production of breeding ewes are: Breeding ewes are subject to the consequences of seasonal changes in Factors that influence the the environment, directly through the production of rams are: influence of climate on the animal itself, • Rams must be functionally effective: and indirectly through variation in the they must have healthy reproducpastoral resources which provide most tive organs and strong, healthy legs. of her nutrition. Performance must be considered in light of the management system and genetEwe colostrum is the first feed for the new-born lamb ics of the breed. and the key to its survival. Proper new-born lamb care • Ewes must be is a critical component of herd profitability. Photo: functionally Pixaby.com.
efficient. A healthy udder with two normal, healthy teats is essential. Examine the teats regularly in areas where ticks occur. Ewes with hard udders (because of inflammation or blue udder), and those with abnormally thick teats must be culled. Ewes must not be too old when they are mated. They must be culled after 5 to 6 lambing seasons (7 to 8 years). Their teeth become bad, and they cannot walk long distances to find grazing. Ewes must be healthy. Disease conditions such as fever immediately after mating could cause resorption of the foetus and abortion. Young ewes should be mated for the first time at 18 months.
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Breeding season Mate the ewes so that they lamb when grazing is plentiful. Lambs will then have a better chance of survival. It also prevents the buying of expensive feed, and the lambs are ready for the market at an early age. Limit the breeding season to 6 weeks to include two oestrus cycles. When the mating season is too long, flock management (dipping, vaccination and dosing) is more difficult. Pairing weight of the young breeding ewes Ewes typically reach puberty at 5 to 12
New-born lambs. Photo: Pixaby.com. 22
ProAgri BNZ 20
