ترجمه مقاله همبستگی بین خون و لپتین سرم شیر در بزها و رشد فرزندانشان

Secreted from both fat and mammary gland tissue, leptin is a hormone that has been found in the milk of a variety of species and is positively correlated with animal body condition. It has been hypothesized that milk leptin ingested by offspring early in the postnatal period may influence growth and development of the offspring. However, it has not been determined if leptin is found in goat milk and if milk leptin levels are correlated with the growth of kids. Therefore, the objectives were to determine if goat milk serum contains leptin and to investigate possible correlations of milk and serum leptin in does and subsequent growth of their offspring. To conduct the study, Boer and Boer crossbred meat type does were used in two Experiments (Exp). Blood samples (via jugular venipuncture) and milk samples were collected within 2 hours of kidding (= d 0) from 20 (Exp 1; conducted in the Spring) or 22 does (Exp 2; conducted in the Fall) and were collected again on days 0.5, 1, 3, 5, 7, 14, 21, 28, 35, 42, 49, and 56 (Exp 1) or days 0.5, 1, 2, 3, 4, 5, 6, 7, 14, and 21 (Exp 2). Body weights of kids were taken at d 0, and body weights of both kids and does were measured weekly beginning on d 7 (kids, Exp 1) or d 21 (does, Exp 1) or on days 0.5, 1, 2, 3, 4, 5, 6, 7, 14, and 21 (Exp 2). Blood and milk serum leptin concentrations were determined using radioimmunoassay. Leptin was detected in milk and averaged 4.4 ± .32 ng/ml (Exp 1) and 18.1 ± .95 ng/ml (Exp 2) on d 0, decreasing to 1.0 ± .31 ng/ml on d 56 (Exp 1) and 2.9 ± 0.2 ng/ml on d 21 (Exp 2) with day postpartum and doe milk serum leptin negatively correlated (r 2 = -.07; p < 0.0001 for Exp 1 and r 2 = -.21, p < 0.0001 for Exp 2). Days postpartum and blood serum leptin were positively correlated in Exp 1 (r 2 = .02; p < 0.02) only. As expected, positive correlations (p < 0.01) were found between leptin and doe body condition (r 2 = .17, Exp 1 and r 2 = .03, Exp 2) and doe body weight (r 2 = .20, Exp 1 and r 2 = .06, Exp 2). In conclusion, leptin was present in milk and blood serum of does and was correlated with doe body weight and body condition but not with kid body weight.