Effects of dietary ferulic acid on reproductive function and metabolism of pre-pubertal hairbreed ewes during the anestrous season

This study aimed to evaluate the effects of dietary supplementation of ferulic acid (FA) on reproductive tract weight (RTW), ovarian activity and serum concentrations of some metabolites and thyroid hormones of pre-pubertal hairbreed ewe lambs during the natural anestrous season. Twenty Dorper x Pelibuey crossbred ewe lambs (initial body weight = 28.5 ± 0.5 kg and age = 5.0 mo) were fed a basal diet and assigned to two treatments (n = 10) under randomized complete block design: FA supplementation to dosages of 0 (control) or 300 mg of FA/d animal−1. Females were treated with FA during 34 d and then slaughtered to evaluate RTW and ovary. Blood samples were collected at days 1 and 34 to determine serum concentrations of metabolites (i.e. glucose, cholesterol, triglycerides, urea and total protein) and thyroid hormones. Final weight, dry matter intake, and serum concentrations of metabolites (except glucose) and thyroid hormones were unaltered by FA. Compared to control, FA-fed ewe lambs had lower (P = 0.05) serum glucose level but higher (P ≤ 0.05) RTW, ovarian mass, number of larger follicles and corpus luteum (CL). While percentage of ewe lambs with small follicles and number of small follicles per female did not vary, percentage of ewe lambs with large follicles and CL increased (P = 0.02) with FA. In conclusion, FA supplementation improves the reproductive tract development and ovarian activity of pre-pubertal hairbreed ewe lambs during the natural anestrous season. An improvement in functionality of the glucose-insulin system could be related with this benefic effect of FA.