Influence of Genetics and Diet on the Development of Diabetes in Yucatan Miniature Swine

Abstract

The intent of this study was to examine the effect of a diet nutritionally similar to that consumed by most Americans on Yucatan miniature swine that have been bred for enhanced and impaired glucose tolerance. Seventeen Yucatan miniature pigs from the glucose-intolerant line (low K) and 17 from the glucose-tolerant line (high K) were selected. The oral glucose tolerance (OGT) of both groups of pigs was determined. After the OGT test (OGTT), 13 low K pigs and 12 high K pigs were placed on the American Swine Diet (ASD). The remaining animals were left on the regular swine diet. After 5 months, the pigs were again tested with an OGTT. Mean plasma glucose levels observed during the OGTT showed significant differences between the low K and high K groups on ASD at all time intervals from 60 to 150 minutes postdosing. Serum insulin levels in the high K group were significantly elevated over those in the low K group during the OGTT at 10, 20, and 30 minutes prediet, and at 10 minutes after 5 months on diet. Both low and high K groups showed a dietary effect with an elevated plasma glucose response to an OGTT, although the mean increase was not significant in the high K group. In the low K group, plasma glucose levels were significantly elevated (P < 0.05) over prediet values at 20, 30, 60, 90 and 120 minutes. In addition, 7 out of the 10 low K pigs tested at 5 months developed insulin resistance, and noninsulin-dependent diabetes.