Reproductive parameters and metabolic profile of repeat breeder cows

摘要

The objectives of the present study were to evaluate the reproductive parameters of 200 Holstein dairy cows, to study some factors that may influence these parameters and to characterize the metabolic profile of repeat breeder cows (RBC). The experiment was carried out on a private farm located in the North of Algeria. Fertility was estimated for each cow by calculating the parameters: Calving-First service interval (CFSI), calving-conception interval (CCI), calving-calving interval (CI), first service - conception rate (FSCR) and fertility index (FI). Parity, dairy production and BCS were used as covariate to determine their effect on CCI and FSCR dependent variables. Blood serum parameters such as glucose, total protein, triglycerides, cholesterol, urea and B-hydroxybutyrate were assayed by spectrophotometry. Insulin and progesterone serum levels were detected by immunological tests. There was a high CS1 interval. Also, 44% of animals had a prolonged CCI (110 days) and the FSCR was estimated at 42%, below the recommended values (60%). RBC were noted in 35% of the total, higher than the intended standard ( 15%). FSCR and CCI were significantly influenced by parity and BCS (P 0.001). No significant milk yield effect on FSCR were reported (P 0.05) but CCI was significantly related to this parameter (P 0.001). RBC were characterized by low levels of insulin and high urea concentrations compared to fertile females (P 0.001). In the conclusion, the reproduction parameters obtained in this study were very far from the standard objectives recommended for effective management of reproduction. It can be due to bad heat detections or/and undernutrition. These parameters were influenced by parity, BCS and milk production. Concentrations of insulin and urea can have some effects on reproductive problems such as repeat breeding and they help to understand potential mechanisms impairing fertility in RBC.