Assuntos
Carcinoma/veterinária , Doenças dos Bovinos/patologia , Glândulas Mamárias Animais , Neoplasias/veterinária , Complicações Neoplásicas na Gravidez/veterinária , Animais , Carcinoma/patologia , Bovinos , Feminino , Metástase Linfática , Neoplasias/patologia , Gravidez , Complicações Neoplásicas na Gravidez/patologiaRESUMO
Eight-day old broiler cockerels received 0, 1, 10, or 100 ppm dietary hexachlorobenzene (HCB) for 25, 38, or 52 days. Treated birds grew faster for the first 25 days, but the trend was reversed at later times so there was no net weight difference at 52 days. Birds receiving 100 ppm dietary HCB had significantly enlarged adrenal glands at 38 days and enlarged livers at 38 and 52 days. Equilibrium concentrations in adipose tissue 12 to 13 times the dietary concentration were reached by 23 days in birds receiving 10 or 100 ppm HCB. Birds receiving 1 ppm concentrated HCB more effectively in the fat and did not reach equilibrium until 23 to 38 days.
Assuntos
Galinhas , Clorobenzenos/farmacologia , Hexaclorobenzeno/farmacologia , Animais , Estatura/efeitos dos fármacos , Encéfalo/anatomia & histologia , Fígado/anatomia & histologia , Masculino , Tamanho do Órgão/efeitos dos fármacosRESUMO
Polychlorinated biphenyls (Aroclor 1242 and 1254) were fed at 20 p.p.m. to hybrid broiler cockerels between one and nine weeks of age in three dietary variations. The Aroclors did not affect growth or feed efficiency and no consistent histopathological lesions could be attributed to them. There was a low incidence of hydropericardium in birds receiving Aroclor 1254. Fatty liver was observed in some birds receiving Aroclor 1242 and a single bird receiving this PCB exhibited liver necrosis. Moderate increases in liver weight and mild decreases in the relative weight of the spleen were attributable to PCB.
Assuntos
Arocloros/farmacologia , Galinhas/crescimento & desenvolvimento , Dieta , Bifenilos Policlorados/farmacologia , Tecido Adiposo/metabolismo , Glândulas Suprarrenais/anatomia & histologia , Animais , Arocloros/toxicidade , Peso Corporal , Galinhas/metabolismo , Gorduras na Dieta/metabolismo , Proteínas Alimentares/metabolismo , Fígado Gorduroso/veterinária , Fígado/anatomia & histologia , Masculino , Tamanho do Órgão , Derrame Pericárdico/veterinária , Doenças das Aves Domésticas/induzido quimicamenteRESUMO
An electron microscopic study of intestinal epithelial cells of neonatal piglets infected with transmissible gastroenteritis (TGE) virus revealed a unique parasite-host cell interaction. Entry of the TGE virus into intestinal epithelial cells of newborn piglets is mediated through a network of cytoplasmic tubules of plasmalemma origin. the tubules, called microcanaliculi, are morphologically distinct from endoplasmic reticulum and Golgi. In uninfected animals similar tubules appear to be responsible for the indiscriminate uptake of large quantities of macromolecules from colostrum during the first few days of life.Thin-section profiles of plasmalemma invaginations resembled tubules or canals and frequently contained viral particles. TGE viral particles developed and accumulated within cytoplasmic vacuoles. Initially the vacuoles were continuous with the microcanaliculi formed by deep plasmalemma invagination. Mature viral particles were 60 to 85 mu in diameter with an electron dense doughnut-shaped nucleoid surrounded by a trilaminar membrane which resembled the vacuolar wall. Abundant evidence of viral effects was observed in absorbtive epithelial cells of the jejunum and ileum but not of the duodenum. The ability of absorbtive intestinal epithelial cells to form deep cytoplasmic tubular invaginations is temporally related to the pathogenesis of TGE and may explain in part why pigs usually are fatally affected by TGE only during the neonatal period.
