title: Early supplementation of starter pellets with alfalfa improves the performance of pre- and postweaning Hu lambs.
abstract: This study aims to determine the effects of alfalfa supplementation on the pre- and postweaning performance, rumen development, and feed transition in starter diet-fed lambs. Six of 66 male Hu lambs were slaughtered at the age of 10 d to serve as a control. The other 60 lambs were randomly allocated to 2 dietary treatments: milk replacer and starter pellets without (STA) or with free-choice chopped alfalfa (S-ALF). The animals were offered 300 g/d of the concentrate mixture and had free access to alfalfa after weaning at the end of wk 4 (age 38 d). The alfalfa inclusion in the S-ALF group tended to increase the starter intake before weaning, significantly increased the concentrate intake soon after weaning ( < 0.05), and increased the BW ( < 0.01) and ADG ( < 0.10) in pre- and postweaning lambs. The S-ALF group had heavier carcasses ( < 0.05), rumens ( < 0.05), reticula ( < 0.05), omasums ( < 0.10), abomasums ( < 0.05), and visceral organs ( < 0.10) than the STA lambs after weaning. Alfalfa supplementation increased ( < 0.05) the rumen papillae length and the ratio of the duodenal villus height to the crypt depth; it also decreased ( < 0.05) the concentration and molar proportion of propionate in wk 1 and 5. The STA lambs had higher ( < 0.01) blood concentrations of globulin and blood urea nitrogen and lower β-hydroxybutyrate after weaning. The STA group also had a higher incidence of feed plaque. From the above results, we infer that the free-choice addition of chopped alfalfa to starter diets is beneficial to rumen development, relieves weaning stress, and improves the performance of lambs.
authors.forename: B
authors.initials: B
authors.lastname: Yang
authors.forename: B
authors.initials: B
authors.lastname: He
authors.forename: S S
authors.initials: SS
authors.lastname: Wang
authors.forename: J X
authors.initials: JX
authors.lastname: Liu
authors.forename: J K
authors.initials: JK
authors.lastname: Wang
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000097:blood; D000821:Animal Feed / Q000032:analysis*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001806:Blood Urea Nitrogen; D004032:Diet / Q000662:veterinary*; D019587:Dietary Supplements; D008297:Male; D000455:Medicago sativa; D008892:Milk; D012417:Rumen / Q000254:growth & development; D012756:Sheep / Q000502:physiology*; D014886:Weaning; D015430:Weight Gain
chemical_list: D020155:3-Hydroxybutyric Acid