Abstract This study aimed to verify the impact of high-fat diet consumption for a prolonged period on oxidative stress, fetal growth, umbilical vascular system, and placental structures in pregnant goats. Twenty-two pregnant goats were grouped into the control diet (n= 11) and fat diet (n = 11). Flaxseed meal was added to the fat diet, replacing the corn grain of concentrate, from gestational day 100 to delivery date. Diets were isonitrogenous and isoenergetic, differing in fat content (2.8% vs. 6.3% dry matter). The fat group showed higher feed intake and total plasma lipid levels than the control group (P < 0.001). No difference was found in placentome, and umbilical vascular development. Fat diet-fed goats exhibited a lower systolic peak in the umbilical artery. At delivery, placental traits were similar with the exception of the cotyledon width (P = 0.0075), which was smaller in the fat group and cotyledon surface (P = 0.0047) for multiple pregnancy of fat diet. Cotyledonary epithelium showed more intense staining of lipid droplets and a greater area for lipofuscin staining in the fat group compared to control group (P < 0.001). The mean live weight of the kids was lower in the fat group in the first week after delivery than in control group. Thus, in goats, the continuous administration of a high-fat diet during pregnancy does not appear to modify the fetal-maternal vascular structures but has an impact on a part of the placental structure; therefore, its use must be carefully evaluated.

Abstract This study aimed to investigate the reproductive effects of adding monosodium glutamate (MSG) to the diet of goats. Eleven adult goats received synchronized estrus and follicular waves using three prostaglandin analog injections every seven days. Goats allocated to individual pens received 1 g/kg BW of MSG in their diet for 23 days (MOGLU group, n = 6), whereas the control group (n = 5) maintained the base diet. The supplemented animals showed an increase in dry matter intake (P < 0.0001) and a reduction in heart rate (P < 0.05), respiratory rate, and ruminal movement (P < 0.001). Surface and rectal temperatures were higher in the MOGLU group, (P < 0.0001) with a significant increase in the afternoon. There was an increase (P < 0.05) in the frequency of behaviors related to rumination, defecation, and urination in the MOGLU group, and a reduction in behaviors associated with stress (P < 0.05). No differences were observed in the plasma levels of proteins, albumin, urea, cholesterol, or triglycerides. Glucose levels were lower (P < 0.05) in the MOGLU group, which also showed increased glutathione peroxide levels during the induction of ovulation. Supplemented animals recorded a larger number (P < 0.05) of follicles throughout the experimental period and higher intraovarian blood perfusion (P < 0.05) during ovulation induction. We conclude that MSG exerts a positive effect on the reproductive response in goats and therefore represents an effective nutritional supplement.

Abstract This study aimed to investigate the effect of a short glutamate supply on the ovarian response in goats with low body condition scores. Twenty-one goats had their estrus and follicular waves synchronized using three injections of prostaglandin analog at seven-day intervals. Goats were allocated to groups receiving 10 mg/kg LW (iv) of glutamate administered in a single dose (group LBCG1, n = 7) or in two doses five days apart (group LBCG2, n = 7). The control group (LBC; n = 7) received saline solution. Glutamate treatment did not affect glucose, cholesterol, or glutathione peroxidase levels, body weight, or adipose deposits. During the experimental period, the LBCG2 group showed a higher (P < 0.05) number of follicles (> 3 mm) and an increase in follicle diameter (P < 0.05). Glutamate supply improved (P < 0.05) the intraovarian Doppler blood area size in the LBCG groups, and the second dose in LBCG2 also induced a higher (P < 0.05) systolic and diastolic peak of the ovary artery. After ovulation induction, LBCG2 exhibited a high (P < 0.05) volume of the corpus luteum and vascularized area. We concluded that the supply of two doses of glutamate five days apart was efficient in ovarian stimulation in goats with a low body condition.

Abstract This study examined the effect of glycerin supply strategies in different short-term protocols on follicular dynamics and ovulatory rate in Morada Nova sheep. Eighteen Morada Nova ewes with body condition > 2.9 had their estrus and follicular waves synchronized using three injections of prostaglandin analogue at seven-day intervals. All animals received the same diet during 21 days, which consisted of a total mixed ration (TMR) based on chopped elephant grass and concentrate twice daily. In thecontrol group (n=9), ewes were fed the TMR diet. In the other four groups, ewes received 150 mL of glycerol daily, supplied as an oral drench or mixed in the TMR during three or seven days prior to the application of thethird PGF2 alfa analogue. These groups were named as follows: Drench3d (n=10), Drench7d (n=8), TMR3d (n=9) and TMR7d (n=9). Follicle dynamics were monitored by ultrasonography, and plasma glucose and glutathione peroxidase levels were measured at the third prostaglandin administration. Six days after the final PGF2 alfa analogue dose, ovulatory rate was measured by laparoscopy. Glucose was higher (P< 0.001) in the glycerin-treated groups than in control group (83.7 ± 1.7 vs. 68.4 ± 4.5 mg. dL-1; P < 0.001). Ewes in the TMR3d, Drench7d and TMR7d groups had a greater (P < 0.001) number of large follicles (≥ 3 < 5 mm), and the presence of follicles larger than 5 mm was observed. In the same groups, at the third PGF2 alfa analogue dose, a greater (P < 0.001) number of growing follicles (> 3 mm) and a larger size of the largest follicle (P < 0.001) were also recorded. Ovulation rate was 30% higher in the groups that received glycerin for seven days (1.6 ± 0.1 53 vs. 1.1 ± 0.1; P < 0.05), and they also exhibited a 38% reduction in glutathione peroxidase. Thus,the use of glycerin in Morada Nova sheep as a source of energy in short-term supplementation for increase ovulation rate is an efficient strategy when provided for seven days, either orally or in the feed.