Ghrelin, the endogenous ligand of the growth hormone secretagogue receptor, is released pre-prandially and during periods of negative energy balance, exhibiting anti-fertility properties. In this study, twenty ewes were divided into two groups: a ghrelin-treated group receiving 1.25 μg/kg body weight (BW) of ghrelin per day via mini-pumps for 28 days and an untreated control group. Estrus was synchronized, superovulation was induced with FSH, and embryos and follicular fluid were collected six days post-estrus. Blood samples were taken to measure LH, progesterone, and anti-Müllerian hormone (AMH) concentrations. Results indicated that in treated animals, preovulatory LH surge was weaker, and progesterone levels were lower than in controls. Differences were observed in the superovulatory response and the number of collected embryos, both being higher in controls. While AMH levels did not differ between groups at the beginning of the experiment, they were lower in treated animals at the time of FSH administration. Treated ewes exhibited a reduced number of small follicles, and their follicular fluid contained lower AMH concentrations than the controls. These findings suggest that ghrelin plays a direct role in regulating LH secretion from the pituitary and in controlling ovarian follicle development, highlighting the strong interaction between nutrition and fertility.

The left displacement of the abomasum (LDA) is a common condition in dairy cows that can significantly impact their welfare, productivity, and fertility. This study was carried out in Greek dairy farms over a period of 3 years. To ensure early detection, the farmers were trained to accurately identify the disease. The reproductive performance and milk production of 306 cows was assessed by considering the time to the first estrus, the calving-to-conception interval, and the number of artificial inseminations required for the establishment of pregnancy. Uterine health status, the timing of disease diagnosis, and the season of the year were also evaluated. In a separate study, the outcomes of 26 cases where cows suffered LDA and underwent surgical treatment with a delay of at least one week from disease onset, were compared to those of cases promptly treated. The results indicate that even early identification and treatment of LDA affects fertility and milk yield; these impacts worsen with the co-existence of uterine infections of affected. However, in late-treated cases, all reproductive and production indices show significant deterioration. Our findings suggest that timely diagnosis of the disease, preferably by the farmer, ensures minimal losses in cows affected by LDA.