Effect of long-term or short-term supplementation of high energy or high energy-protein diets on ovarian follicles and blood metabolites and hormones in ewes

Abstract This study was conducted to compare the effect of high energy or high energy-protein diets in long-term (16 days, flushing) or short-term (6 days, focus feeding) supplementation period on ovarian performance and serum metabolites and hormones of ewes. For this purpose 40 cyclic Naeini ewes (40 ± 1 kg BW and 2–3 years of age) were randomly assigned to experimental groups: 1—Control (CON), 2—long-term high energy diet (LE), 3—short-term high energy diet (SE), 4—long-term high energy-protein diet (LEP), and 5—short-term high energy-protein diet (SEP). Ewes were housed in the individual pens with free access to food and water. The estrous cycle of ewes was synchronized with insertion of intravaginal progesterone sponges for a 12-day period. Follicular development was observed by ultrasound four days before to one day after sponge removing (−4 to +1) and blood was sampled once a day during this time. Results showed that LE and SE groups had more large-size (>5 mm) follicles ( P  P  P