Monitoring blood glucose levels in female mink during the reproductive cycle: 1. Prevention of hyperglycemia during the nursing period

Abstract

Nursing sickness, the largest cause of death in female adult mink, is a metabolic disorder characterized by hyperglycemia. The impacts of body condition, dietary supplements, and reproductive status on the blood glucose concentration in female mink during the reproductive cycle were investigated. Mink dams on 3 farms were assigned to receive either herring oil (HerO) or chromium picolinate (CrPic) or to be in a control group, receiving only the basal diet, for 6 wk at the onset of lactation. Hyperglycemia was observed throughout the reproductive cycle. Significant differences in blood glucose levels were observed between farms, emphasizing the importance of herd genetics and of animal management and feeding practices in glycemic regulation. Female mink exhibiting hyperglycemia early in the reproductive cycle tended to remain hyperglycemic and to have poorer health and fewer kits. Glucose levels > 7 mmol/L can be considered critical in this regard. Supplementing the diet with CrPic reduced the blood glucose concentration. Results from this study suggest that a diet containing high-quality n-3 polyunsaturated fatty acids, high levels of carbohydrate, and CrPic supplementation may help the nursing mink dam maintain a normal blood glucose concentration during lactation.

Figure 1

Mean blood glucose concentrations in mink females at breeding, gestation, and lactation according to body condition score: very thin (n = 0, 0, 3), thin (n = 4, 6, 13), ideal (n = 100, 78, 70), heavy (n = 3, 15, 11), and obese (n = 0, 3, 1).

Figure 2

Mean blood glucose concentrations in mink females at breeding, gestation, and lactation according to number of kits in the litter at late lactation: none (n = 8), 1–3 (n = 11), 4–6 (n = 66), and 7–9 (n = 13). A total of 9 females died during the experiment, 5 between breeding and gestation and 4 between gestation and the end of the study.