Analysis of body weight in various color varieties of American mink (Neovison vison) and the relationship between female body weight and reproductive performance

Abstract

The aim of the study was to analyze the body weight of different color varieties of breeding mink and to assess the relationship between the body weight of females and the reproductive indexes obtained. The research material consisted of 3499 one-year-old American mink females of five color varieties: White Regal, Standard Black, Pearl, Silverblue and Black Cross. Six body-weight ranges of female mink were distinguished. The following were analyzed within each range: pregnancy length, fertility, average number of kits born in a litter, average number of kits born alive in a litter. It was also examined whether there was a relationship between the color variety and the average body weight of females attained during the pre-mating body condition adjustment. There were statistically significant differences in the body weight of the analyzed color varieties of mink. It was also found that the body weight of females obtained in the period of breeding preparation influences the resulting reproductive performance. Higher body weight positively influences fertility, while animals of an average body weight produce larger litters of kits.

Nursing of mink in nest boxes insulated with different materials

“…The survival rate of the young is determined by many factors, including color variety, age of the mother, and litter size Kołodziejczyk 2006, Kołodziejczyk andSocha 2012]. Schou and Malmkvist [2017] and Seremak et al [2013] found that litters that were too numerous had a higher mortality rate than litters that were less numerous, which was due to the fact that pups in larger litters (more than 9 young) are much smaller and the mother has limited feeding capacity. Due to the fact that mink are born naked, blind and deaf, weighing about 9-12 grams, especially during the early stages of mink rearing, maintaining an adequate nest temperature is a problem, as mink do not have a developed thermoregulatory mechanism and are prone to rapid hypothermia due to their relatively large body surface area relative to volume [Brown and Lasiewski 1972, Harri et al 1991, Castella and Malmkvist 2008.…”