Dietary manipulation causes childhood obesity-like characteristics in pigs

An animal model to study complications resulting from childhood obesity is lacking. Our objective was to develop a porcine model for studying mechanisms underlying diet-induced childhood obesity. Pre-pubertal female pigs, age 35 d, were fed a high-energy diet (HED; n = 12), containing tallow and refined sugars, or a control corn-based diet (n = 11) for 16 wk. Initially, HED pigs self-regulated energy intake similar to controls, but, by wk 5, consumed more (P < 0.001) energy per kg body weight. At wk 15 and 22, pigs were subjected to an oral glucose tolerance test (OGTT); blood glucose increased (P < 0.05) in control pigs and returned to baseline levels within 60 min. HED pigs were hyperglycemic at time 0, and blood glucose did not return to baseline (P = 0.01), even 3 h post-challenge. During OGTT, glucose area under the curve was higher and insulin area under the curve was lower in HED pigs compared to controls (P = 0.001). Pigs given 6 wk of dietary intervention, consuming a control diet, marginally improved glucose area under the curve and LDL-cholesterol although insulin area under the curve was unaffected. Chronic HED intake increased (P < 0.05) subcutaneous, intramuscular, and perirenal fat deposition, and induced hyperglycemia, hypoinsulinemia, and low-density lipoprotein hypercholesterolemia; however, a 6 wk dietary intervention partially recovered a normal physiology. These data suggest pre-pubertal pigs fed HED are a viable animal model for studying childhood obesity.