海带水解物对泌乳奶牛生产性能及血清生化、抗氧化与免疫指标的影响

This experiment was conducted to investigate the effects of supplementation of Laminaria japonica hydrolysate (LPH) on performance and serum indexes of dairy cows. Ninety high⁃yield Holstein dairy cows with similar body condition, milk yield of (41.2 ±6.6) kg / d and lactation days of (125 ±16) d were randomly divided into 3 groups with 30 cows in each group according to randomized grouping design. Cows in the three groups were fed the same basal diet, and the three groups were complementally fed 0 (control group), 15 (L group) and 30 g / (head·d) LPH (H group), respectively. The experiment lasted for 60 days. The results showed as follows: 1) dairy cows complementally fed 15 g / (head·d) LPH had no significant effects on dry matter intake and milk yield (P > 0. 05), while dairy cows complementally fed 30 g / (head · d) LPH could significantly reduce dry matter intake without affecting milk yield (P <0.05) . 2) The supplementaion of 15 or 30 g / (head·d) LPH significantly increased milk protein content (P < 0. 05), and there was a trend of decrease in somatic cell number (P = 0.07), while the it had no significant effects on milk fat, lactose, total solids and milk urea nitrogen contents (P >0.05) . 3) The supplementaion of 15 or 30 g / (head·d) LPH significantly decreased serum total cholesterol content (P <0.05) . Serum glucose and high density lipoprotein cholesterol contents of cows in H group were extremely significantly increased (P <0.01), serum total protein content of cows in L group had an upward trend (P = 0.06), and serum low density lipoprotein cholesterol (LDL⁃C) content in group H tended to decrease (P = 0.09) . The supplementaion of 15 or 30 g / (head·d) LPH had no significant effects on the contents of albumin, triglyceride, urea nitrogen and the activities of alanine aminotransferase, aspartate aminotransferase in serum (P >0.05) . 4) The supplementaion of 15 or 30 g / (head·d) LPH extremely significantly increased serum total antioxidant capacity (P < 0. 01), significantly increased serum superoxide dismutase activity (P <0.05), and significantly decreased serum malondialdehyde content (P < 0. 05) . 5) The supplementaion of 15 or 30 g / (head·d) LPH extremely significantly increased the contents of serum immunoglobulin A and immunoglobulin G (P < 0. 01), and the supplementation of 15 g / (head · d) LPH significantly increased the content of serum immunoglobulin M (P <0.05) . In conclusion, the supplementation of 15 g / (head·d) LPH can improve serum indexes, enhance antioxidant capacity and immunity of dairy cows without affecting dry matter intake and milk yield, at the same time, it can delay the decrease of milk yield, increase the milk protein content and reduce the milk somatic cell count. © 2023 Chinese Journal of Animal Science and Veterinary Medicine Co., Ltd.

Effects of Laminaria japonica Hydrolysate on Performance,Serum Biochemical,Antioxidant and Immune Indexes of Dairy Cows