The effects of pre and postnatal nutritional restriction on allometric growth of thoracic and abdominal organs of Santa Inês lambs were evaluated. Sixty-eight lambs were divided into three groups: lambs with prenatal nutritional restriction (PRER), lambs with postnatal nutritional restriction (POSR), and lambs without restriction (control). The lambs in each group were slaughted at birth, 10kg, 15kg, 25kg, 35kg, and 45kg of live weight. After slaughtering, heart, lungs, trachea and esophagus, liver, spleen, pancreas, rumen-reticulum, abomasum, omasum, and small and large intestines were individually weighted. At birth, PRER affected the weights of heart, lungs, trachea and esophagus, abomasum, pancreas, and spleen, with means of 54g, 16g, 22g, 16g, 2g, and 5g, respectively. However, the organs of the PRER lambs at 15kg of live weight showed the same weight of that organs of the others animals, indicating a compensatory growth. POSR did not affect the weight of the organs of thoracic cavity;however, in abdomen cavity, rumen, small intestine, and liver were affected, with means of 385g, 488g, and 371g, respectively. The allometric study showed that rumen and omasum presented a positive heterogonic development; while abomasum presented a negative heterogonic development; and liver, small and large intestines showed an isogonic development. The pancreas of control and POSR lambs presented an isogonic development, while pancreas of PRER lambs showed a positive heterogonic delevopment. In this experiment, the alimentary restriction affected weigth, growth, and type of development of internal organs of Santa Inês lambs, evidencing the importance of the feeding for ewes at the last third of gestation as well as for the lambs during the growth phase.
lamb; allometric growth; visceral mass; alimentary restriction
