Determining the reproductive potential of repair heifers

Abstract

Reproduction and culling of productive animals are the main factors that affect the number of cows in a herd. Timely determination of fertility in replacement heifers with subsequent culling of problem heifers will help reduce direct economic losses in breeding dairy cattle. When making a diagnosis, veterinarians should exclude all forms of temporary or permanent infertility, including Congenital anomalies (infantilism, freemartinism, deformities, etc.).In order to establish the hormonal status of heifers-freemartin in the blood serum, the concentration of sex hormones (progesterone, estradiol-17ᵦ, and testosterone) and anti-Müllerian hormone (AMH) was determined.Studies of the level of AMH using an enzyme-linked immunosorbent assay in blood serum have proven the possibility of early assessment of fertility in heifers. This method will allow early culling of Freemartin heifers from a productive herd. The study of AMH levels showed that its amount directly correlates with fertility in cattle, regardless of the period of the estrous cycle. When the concentration of AMH in the blood serum is below 100 pg / ml, heifers are not capable of fruitful insemination, while a high level of anti-Müllerian hormone (more than 380 ng / ml) makes it possible to successfully fertilize animals on the first attempt. All clinically healthy replacements obtained during a single pregnancy were successfully inseminated. At low concentrations of anti-Müllerian hormone, Freemartin heifers were sterile, even after hormonal stimulation (Co-Synx) and sperm doses were administered without clinical manifestation of sexual desire.The introduction of testing for the level of AMH by the ELISA method in the mandatory gynecological clinical examination of cattle in livestock enterprises is expedient and effective.

Reproductive features of PRRS-convalescent large white pigs after porcine reproductive and respiratory syndrome

“…The earliest diagnosis of low-producing gilts is the main task when working with parent females at the holding. Timely determination of fertility in replacement gilts with subsequent culling of defected gilts will help to reduce direct economic losses in raising sows [10]. In the production environment, the replacement gilts were subdivided into two groups: gilts born from PRRS-convalescent sows (experimental group), and gilts born from sows with an average litter (control group).…”

Effect of Mycotoxins on Reproduction and Milk Quality of Dairy Cattle and its Amelioration by Natural Adaptogen “Betulin”

“…In concurrence with the current trend of intensifying dairy cattle rearing systems aimed at maximizing production and profits, new standards for feeding highly productive animals are being developed using various feed additives and supplements (Korotkiy et al 2023;Avdeenko et al 2021;Sherimova et al 2022;Fedotov et al 2020). However, in large livestock enterprises, nutritional infertility is diagnosed annually in 25-30% of infertile cows, indicating that this problem is quite widespread in dairy cattle breeding (Gnezdilova et al 2021;Yakhaev et al 2020).…”