Influence of Biosteel on the reproductive ability of American Mink, the Standard dark brown genotype with different defensive response to humans

Abstract

The article presents the results of studies on the effect of different doses of Biosteel, when administered orally, on the reproductive ability of American mink females of the Standard dark brown (+/+) genotype with a positive and negative defensive reaction to humans. The studies were carried out at the Department of Obstetrics, Anatomy and Histology of the Federal State Budgetary Educational Institution of Higher Education of the Novosibirsk State Agrarian University and based on the Mustelidae Genetics Sector of the Center for Collective Use “Gene Pools of Fur and Agricultural Animals” of the Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences. In the technology of reproduction of animals of the experimental and control groups, the system of conducting the rut, generally accepted on fur farms, was used. Biosteel was applied to females and males of Standard dark brown (+/+) American mink of manual and aggressive types of behaviour at a dose of 0.05 ml/kg and 0.025 ml/kg of body weight before mating for five days and during mating for five days. The effectiveness of using Biosteel to improve the reproductive function of females depended on its dose and the type of animal behaviour. Compared with the minks of the control groups, the females of the experimental groups showed higher rates of reproductive ability. In the group of tame females that received the drug with food at a dose of 0.05 ml/kg of body weight, there were no dead females, the survival of puppies in the first seven days of life increased by 3.8 times, and there was a tendency to reduce stillbirths. Biosteel had a pronounced beneficial effect on the reproduction of females with an aggressive type of behaviour at a dose of 0.025 ml/kg of body weight: the integral reproduction index increased by 1.13 heads. And the number of females that successfully whelped by 17%, the number of females without offspring decreased by 5.9 times, and the mortality of minnows in the first seven days of life declined by 3.9%. The absolute body weight of the offspring of females by the time of jigging increased by 19.2 – 24.5%, and by 6 – 7 months of age – by 4 – 11%.