Toxic Myopathy of Chicks Fed Cassia occidentalis Seeds

Abstract

SUMMARY Chicks were fed diets containing 0, 0.5, 1.0, 2.0, and 4.0% Cassia occidentalis seeds for 21 days. The 2 highest levels significantly reduced body weights and daily feed intake. Death rates were high from the feeding of 4.0% seeds, and low with the other 4 levels. The semitendinosus muscles of chicks fed 2.0 or 4.0% seeds were pale and edematous upon sacrifice of the birds after 21 days of feeding. In histologic sections, there was focal swelling, fragmentation, and necrosis of myofibers of the semitendinosus muscle. In electronmicroscope studies of the mild muscle lesions there was fragmentation of Z bands and degeneration of I bands; in severe muscle lesions there was necrosis of the sarcomere, preservation of the T system, mitochondrial degeneration, and proliferation of sarcolemmic nuclei.