Preference for safflower oil in rats exposed to a cold environment under free-feeding conditions

There are several benefits to a high-fat diet for animals exposed to cold, including improved tolerance to severe cold, conditions and increased survival rates in cold environments. It is therefore of interest to examine whether animals exposed to cold will selectively consume lipids. We examined the intake of safflower oil (SO) by rats exposed to cold (4 +- 1: 2 deg C) under a feeding condition in which the rats were given free access to SO. Rats exposed to cold consumed more SO than those housed at 25 +- 2 deg C. This finding suggests that rats prefer SO in a cold environment. There was no significant difference in the ratio of calories of SO ingested to that of matter (standard laboratory chow plus SO) ingested between rats exposed to cold and those at 25 +- 2 deg C. The high SO intake also affected cold tolerance and metabolite kinetics in the rats. Factors that affected the SO intake of rats exposed to cold are also discussed.