[Prepartum supplementation of protected choline on metabolic profile and interval between calving and conception of dairy cows]

ABSTRACT During the periparturient dairy cows undergo a large energy demand, at the same time reducing their intake of dry matter. The negative energy balance resulting from this equation leads to severe metabolic disorders in production, and mainly in reproduction. The aim of this study was to evaluate the effect of protected choline on metabolic parameters, reproductive performance, and milk production in cows during the transition period. Fifty-four dairy cows were divided into three groups: control, supplementation with choline for 10 days prepartum (T10) and supplementation with choline for 20 days prepartum (T20). After delivery we measured fructosamine levels, cholesterol, non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHB), aspartate aminotransferase (AST), gamma glutamyltransferase (GGT), and total oxidant (TOS) on days 10, 20 and 30. We also evaluated milk production and interval between calving and conception. There was no effect of supplementation with choline on blood and production parameters. The interval between calving and conception was lower in the T20 group. Choline supplemented by 20 during the antepartum improved reproductive performance of dairy cows, although it did not change the metabolic profile.

摘要 围产期奶牛面临极高的能量需求，同时其干物质采食量会降低。由此产生的能量负平衡会引发生产领域尤其是繁殖相关的严重代谢紊乱。本研究旨在评估保护性胆碱对围产期奶牛代谢参数、繁殖性能及产奶量的影响。试验将54头奶牛分为三组：对照组、产前补充胆碱10天组（T10）以及产前补充胆碱20天组（T20）。分娩后分别于第10、20、30天检测受试奶牛的果糖胺水平、胆固醇、非酯化脂肪酸（non-esterified fatty acids, NEFA）、β-羟丁酸（beta-hydroxybutyrate, BHB）、天冬氨酸氨基转移酶（aspartate aminotransferase, AST）、γ-谷氨酰转移酶（gamma glutamyltransferase, GGT）及总氧化产物（total oxidant, TOS）；同时记录产奶量及分娩至受孕的间隔时长。结果显示，胆碱补充对血液指标及生产参数无显著影响，但T20组的分娩至受孕间隔时长显著更短。产前补充20天胆碱可改善奶牛的繁殖性能，尽管其未改变奶牛的代谢谱。