Depending on the sheep’s age and purpose the feed changes. Feeding sheep at different stages are flushing, pregnancy, lactating ewes, lambs, and Fattening Lambs. Nutrition plays a major role in the overall productivity and health of the flock. Proper sheep management is necessary for keeping feed costs minimal.
Improving the nutritional status of ewes during 3-4 weeks prior to mating is known as ‘flushing‘. Nutrition and body condition of the ewes prior to putting them to ram is important.
Flushing will have effect only if the ewes were in the declining phase of nutritional availability.
Ewes in better body condition will produce more lambs and thus the flushing of leaner ewes will increase fertility by way of increased incidence of oestrus and increased ovulation rate.
The majority of sheep in arid and semi-arid regions are bred 2 to 3 weeks after the onset of rains as they get sudden improvement in the grazing conditions after going through a long nutritional stress period during summer.
To obtain increased lambing rate, the breeding ewes, 4-6 weeks prior to their being bred, should be supplemented with 250 g of concentrate mixture or 500 g of good quality legume hay per head per day.
The fetus makes two-thirds of its total growth during the last 6 weeks of pregnancy.
The consequences of under-nutrition in late pregnancy are reduction in lamb’s birth weight, poor milk production, and poor lamb survival.
Under-nutrition may also result in the occurrence of pregnancy toxemia which results in the collapse and possible death of the ewes. There is a production of ketone and acetone bodies in the blood from the rapid breakdown of body fat to meet the energy requirements of advanced pregnancy. Thus, the number of nutrients, especially energy, must be increased during the latter part of pregnancy to ensure proper, growth of the fetus and high milk production.
Although the greatest demand is for energy at this time, an adequate quantity of protein is also essential. Protein and energy interact to some extent so that their requirements cannot be separated.
An allowance of 600 g of high-quality legume hay or 300 g of concentrate mixture having 12-14 percent DCP and 65-70 percent TDN per head per day during the last one and a half months of pregnancy over and above good grazing is to be ensured. The primipara(giving birth for the first time) may,’ however, be provided only 200 g of concentrate mixture in addition to grazing because higher birth weights may result in difficult lambings. Supplementation with dry tree leaves.
The requirements of energy and protein are higher during lactation. Milk production is affected primarily by the level of current feeding. However, maximum production is dependent on adequate nutrition during both pregnancy and lactation.
Feeding during the first 4 weeks of lactations is particularly critical and affects the lactational performance of the ewe, and hence the growth and survival of the lamb. During early lactation, a sufficient quantity of good quality grazing and supplementary concentrate or legume hay or dry tree leaves should be provided as the demand for energy in lactating is very high.
The lactating ewes require concentrate supplementation on an even higher rate than the advanced pregnancy. Lactation also causes to mobilize body reserves of fat which are replaced with water. It is, therefore, necessary that the ewes should be in good condition at the time of lambing. They should also be fed a high level of energy in early lactation.
A high protein diet improves the yield of milk but at the cost of the body reserves and hence both energy and protein should be balanced in the diet of a lactating sheep.
Supplementing with 800 g of good legume hay at 400 g per day of concentrate mixture for 75 days after lambing in addition to 8-hour grazing on Cenchrus(grass family) pasture has proved highly satisfactory for fast-growing and heavier crosslinked animals under arid and semi-arid conditions.
A lamb should get a sufficient amount of colostrum (first milk) from the mother during the first few days after birth. It imparts passive immunity, through gamma-globulins in which colostrum is very rich, against a number of infectious diseases against which the mother has been vaccinated or to which it has more recently been exposed to. There is no other way of protecting young lambs against these infectious as they do not have their own immune system yet developed.
Colostrum is also a rich source of energy and nourishes the newborn lamb, and acts as a laxative to clear the gut of the meconium. Colostrum is richer than milk in protein, vitamins A and D, cobalt, iron, and lactose. If some lambs are orphaned and no ewes are available for fostering, it is necessary to rear them artificially.
It will be necessary to feed them on milk. Goats can also be used as foster mothers and lambs can be put directly to suckle them. It will require some personal attention and training the lambs to suckle goats.
Artificial feeding of milk using glass bottles with rubber nipples can be adopted, but hygienic measures must be adhered to. Lambs should be started on creep feed as soon as possible after birth. The consumption is negligible during the first 2-3 weeks but will increase with age and weight. The creep ration should be highly palatable and rich in protein. The addition of antibiotics to the creep ration helps in reducing diseases like enterotoxaemia, scours, and pneumonia.
The lambs should be weaned around 2 1/2 to 3 months of age when they have attained a live weight of 12-15 kg. The weaning should be abrupt. The weaned lambs should be provided concentrate ration @ 250 g with a progressive increase up to 400 g per head per day in addition to grazing on a legume-grass pasture to obtain maximum growth.
Feeding of weaned lambs involves a balance between the use of cereals and the forages rich in energy and protein to achieve economic growth. The fattening lambs should be fed special rations high in energy and protein and low in fiber.
The sheep meat available in the Indian markets comes either from old and culled sheep or from male lambs slaughtered any time between 6 months and 1 year of age.
The quality and quantity of the meat produced from the male lambs are very poor due to poor market weight, low dressing percentage, and narrow bone; meat ratio, since these lambs ate maintained on scrub grazing like their dams.
They hardly attain a bodyweight of 15-16 kg at the age of 8-9 months when they are usually marketed. The dressing percentage varies from 35 to 40 and bone: meat ratio from 1:4 to 1:4:25.
Through crossbreeding of native sheep with exotic mutton breeds and intensive feeding of lambs marked improvement can be achieved both in live-weight gains and carcass quality.
A weaning (90 days) weight of about 13 kg in Malpura and Sonadi, about 14.5 kg in Dorset crosses and about 16.0 kg in Suffolk crosses with the native breeds has been obtained by feeding 150 to 200 g concentrate mixture per head per day in addition to suckling and grazing on reseeded Cenchrus pasture.
Feedlot gains of about 12.5 kg in natives and 16.0 kg in crossbreds have been obtained on a feedlot ration containing 50 percent roughages and 50 percent concentrate for 90 days after weaning at 90 days of age.
The feed efficiency has been 14.5 percent in natives and 18.5 percent in crossbreds. In other words for 1 kg gain, natives require 7.0 kg and crossbreds 5.5 kg of feed. The total cost of producing, feeding, and rearing a lamb up to 6 months age worked out to be the same in both natives and crossbreds.
Following the Calendar of Sheep Management practices, will eventually keep the sheep flock healthy.