Restricted feeding may induce serous fat atrophy in male Göttingen minipigs.

Serous atrophy of the fatty tissue of bone marrow is occasionally seen in minipigs. It is not associated with compound toxicity, as it has been observed in both dosing and healthy control groups in toxicity studies, but the etiology and pathogenesis are unknown. However, a nutritional factor is suspected, since minipigs are generally diet restricted. In order to investigate this, newly weaned minipigs were fed different amounts of feed for nine months, after which the bone marrow was evaluated. Serous atrophy was observed in diet-restricted male minipigs fed on a diet based on the nutrient requirements of production pigs, but not in males fed on a diet specially designed for minipigs, at similarly restricted levels. No serous atrophy was observed in females. It was concluded that nutrient requirements of production pigs are not necessarily suitable for minipigs, as a diet based on these nutrient requirements caused total depletion of perirenal fat depots, as well as serous atrophy of the fatty tissue of bone marrow in male Göttingen minipigs at a restricted feeding level.