Effect of passive transfer status on preweaning growth performance in dairy goat kids.

Objective—To evaluate the effect of passive transfer status (determined from measurements of serum lgG concentration at 24 hours after parturition [slgG-24]) on preweaning growth performance in dairy goat kids. Design—Prospective observational study. Animals—20 healthy nursing dairy doe kids in a natural nonintensive breeding environment. Procedures—For each kid, slgG-24 was measured. Body weight was measured at birth and at the time of weaning 30 days (ie, 29 to 31 days) after birth; average daily gain from birth to day 30 and weight at day 30 were used as measures of preweaning growth performance. Regression analysis was used to evaluate associations between slgG-24 and measures of preweaning growth performance. Results—Mean ± SD slgG-24 was 31.7 ± 10.3 mg/mL. Mean body weights at birth and weaning were 4.105 ± 0.981 kg (9.031 ± 2.158 lb) and 9.310 ± 2.554 kg (20.482 ± 5.619 lb), respectively; average daily gain was 0.174 ± 0.072 kg/d (0.383 ± 0.158 lb/d). No significant association was detected between slgG-24 and birth weight. However, slgG-24 was significantly associated with average daily gain (R² = 0.48) and weight at day 30 (R² = 0.56). Each increase in slgG-24 of 1 mg/mL was associated with an increase in average daily gain of 0.005 kg/d (0.011 lb/d) and an increase in weight at day 30 of 0.185 kg (0.407 lb). Conclusions and Clinical Relevance—Results indicated that passive transfer status (determined as slgG-24) was a significant source of variation in preweaning growth performance in dairy doe kids reared in this nonintensive breeding environment. [ABSTRACT FROM AUTHOR]