Study On Application Of Early Weaning For Lamb

Choosed Gansu Alpine fine-wool lamb which was born by Gansu Alpine fine- wool female sheep mated the male Germany Merino as the experiment material, fed the lambs at the same condition of browsing and the same management, designed two factors and three levels—3 different weaning times (30d, 45d and 60d) and 3 different levels of nutrition (milk-replacerⅠ, milk-replacerⅡ, milk-replacerⅢ),divided the lambs to 10 groups at day 7,9 trail groups and 1 contrast group, 6 male lambs and 9 female lambs in each group.Fed the trail groups'lambs different milk-replacers from day 8, weaned one-off at the weaning time(30d, 45d and 60d),fed the milk-replacer 15 days respectively after being weaned,then fattened to day 120,and then they were slaughtered to compare the slaughtering performance and meat quality. Collected the blood of lambs to analyse the effect to physiological and biochemical indexes. And collected the blood of ewes at regular interval to analyse the change of estradiol and progesterone. Analysed the change of ewes'body weight.Conclusions as follow:1.The effect of different milk-replacers and different weaning-times to lamb'growth was different, comparatively speaking, the later affected more obviously. This experiment implemented that weaning at day 45 and feeding lambs milk-replacerⅠor weaning at day 60 and feeding lambs milk-replacerⅢ,both could gain better production benefit,could increase the income $27.58 and $29.51 per lamb respectively at day 60 and day 75.Weaning at day 45,feeding the milk-replacerⅢ,lamb's growth performance was better,the body weight could achieve 17.02kg,was extremely higher than 12.98kg of the contrast group(P<0.01).2.Implemented the early-weaning technology to the lamb, and fed milk-replacer, not only did not hinder the lamb'ability of digesting protein,carbohydrate,and fat,but could also help the lamb digest nutrients,and would be helpful to improve lamb's immunity ability,the total protein in serum reached to 57.69 g/l,54.42 g/l and 58.34 g/l in the group of weaning at day 30, 45 and 60 respectively,which was higher than 53.27 g/l, 52.81 g/l and 50.68 g/l of the contrast group respectively at the same term, but the difference was not remarkable(P>0.05),at the same time,it could also reduce the content of cholesterol,and the index of glucose and urea nitrogen was better than the contrast group,but the difference was not remarkable,too(P>0,05).3.After stopping feeding milk-replacer,fattening the lamb to day 120. At the day 120 ,the highest weight was the group of weaning at day 60, reached to 35.17kg,and the ADG between day 75 to day 120 could reach to 277.2 g/d,which were both extremely remarkable higher than 22.77kg and 144.9g/d of the contrast group(P<0.01), and economic benefit is $52.01 higher than the contrast group per each lamb.And also higher than 33.75kg,275.6g/d and $47.69 per each lamb of the group weaning at day 45.If the economy is abundant,you can adopt the mode of weaning at day 60,if not,take the mode of weaning at day 45.4.At the day 120,the carcass weight of lambs in the group of weaning at day 30,45 and 60 was 12.83kg,14.93kg and 16.26kg,extremely higher than the contrast group 9.44kg (P<0.01),the rate of slaughtering ,the rate of net meat and eye-muscale area of the group weaning at day 60 is the highest ,reached to 44.13%, 39.44% and 12.03 cm2,extremely higher than 33.89%, 27.40% and 7.66 cm2 of the contrast group(P<0.01).The slaughtering performance and meat quality of trail groups were better than contrast group.So,early-weaning can help improve the slaughtering performance and meat quality of the lamb.5.Early-weaning on lamb could help restore the ewe's body condition(weight) after post-natal and post-weaning, the group of weaning at day 30 was the best,the ewes'body weight increased 5.18kg,remarkable high than the contrast group (P<0.05),it indicated that early-weaning could help restore the ewe's body condition, and make them to come into the next propagate period with a better body condition. And weaning at day 30 can make the ewes oestrus earlier than others,about 20 days earlier than the contrast group,so we can breed ahead of time to increase the efficiency of reproducing.And the progesterone content in milk of ewe in the group of weaning at day 45 was 0.728ng/ml, was higher than 0.678 ng/ml of the contrast group, but difference was not remarkable (P>0.05),so early-weaning on lamb can help restore the function of ewe's ovary,and prepare for the next propagate period as soon as possible.Generalizing mode:weaning at day 45,feeding milk-replacerⅢ.