R. Bras. Zootec.01/Dec/2008;37(12):2085-9.
Histopathological alterations in bullfrog tadpoles fed commercial diets with three levels of crude protein
DOI: 10.1590/S1516-35982008001200002
Necropsy and histological examination were made on bullfrog (Rana catesbeiana) tadpoles fed commercial rations with 32, 36, 45 or 55% crude protein (CP) to establish the relationship between dietary crude protein and health of the animal. In the necropsy, the tadpoles did not show externally any changes, however, the liver of animals at all crude protein levels, presented a straw color and stained. Histological analysis showed livers with rarefaction and degeneration of cell protein, intestines, with colitis and flattening of microvilli, spleen with lymphocyte hyperplasia, heart, without alterations, kidneys with glomerulonephritis and areas of tubulonefroses; mononuclear gastritis and hyperplasia and hypertrophy of regional lymph nodes. In all organs, there was hemossiderin deposit. These injuries suggest degenerative nutritional condition, with development of inflammatory processes, spreading to all organs. The results suggest that the animals were fed diets with low biological value proteins, therefore, poor quality, which affects health and performance of the animals. Further studies are necessary to understanding the biochemical behavior of bullfrogs in the tadpole stage, aiming to adequate nutrition of these animals.
Keywords: animal nutrition; bullfrog; pathology; tadpole; tadpole