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چکیده
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may improve the growth rate, rumen development, average daily gain (ADG), and dry matter intake (DMI) of dairy calves. This experiment aimed to study the effect of interaction between milk plane feeding and inclusion of alfalfa hay in starter on the performance, skeletal characteristics, ruminal fermentation and plasma metabolites of dairy calves. Thirty-two 3-d-old Holstein female calves (36.43 ± 2.1 initial BW) were individually housed (n = 8 calves per treatment) and, assigned to 1 of 4 experimental treatment groups in a completely randomized design with a 2 × 2 factorial arrangement. Experimental treatment groups were (1) conventional (COV) milk feeding without forage provision (COV-NF); (2) COV milk feeding with forage provision (COVF); (3) high milk feeding without forage provision (HM-NF); and (4) high milk feeding with forage provision (HM-F). Calves in the COV and high milk methods received 4 or 8 L/d milk, respectively. Forage-supplemented calves received 15% alfalfa hay mixed with the thoroughly ground starter as a total mixed ration. Calves had ad libitum access to water and starter throughout the study. All calves were weaned at 56 d of age and, the experiment was fulfilled two weeks following the weaning. Individual milk intake and solid feed consumption were recorded daily. The interaction of milk plane nutrition and alfalfa provision was significant for the starter and DM intake, with the greatest starter intake for COV-F treatment and DMI for COV-F and HM-NF treatments during the overall period. The greatest ADG during the pre-weaning and overall period and BW at weaning were observed in HM-NF treatment calves. Calves in the HM-NF treatment had the highest final heart girth; however, other skeletal measurements were not influenced by milk plane feeding and alfalfa provision interaction. No interaction was detected between the milk plane feeding and alfalfa provision for plasma glucose, BUN, BHBA, albumin, total protein, AST and ALT concentrations and rumen fermentation attributes. Regardless of alfalfa provision, pre-weaning starter intake, ADG, feed efficiency (FE), post-weaning starter intake, overall starter intake, FE, weaning BW, body length and hip height, and acetate concentration were increased; whereas, total VFA and valerate concentrations were decreased as milk plane increased. performance of dairy calves.
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