RESUMEN
During meat inspection, unusual pigmented lesions were found in the abdomens of 411 sheep from a flock raised in the Northern Tablelands of New South Wales. In each affected sheep there were multiple discrete, soft, yellow homogeneous plaques beneath the parietal peritoneum and extending into marginating facial planes of the diaphragm and body wall. Microscopically, the lesions consisted of focal granulomatous peritonitis with intracellular acicular refractile golden-brown crystals. Energy dispersive X-ray spectroscopy revealed intralesional barium and selenium, two components of an injectable selenium compound administered to the sheep 6-8 months prior, which contains the yellow pigment, iron oxide. The mechanism of subperitoneal deposition of the compound could not be confirmed, but is presumed to have involved intraperitoneal injection of barium selenate. Meat inspectors and diagnosticians should consider barium selenate injection-site granulomas as a possible explanation for yellow pigmented lesions, especially in livestock from selenium-deficient areas. Animal care providers should be aware that incorrect administration of barium selenate can result in losses from condemnation or downgrading of meat product.
Asunto(s)
Compuestos de Bario/efectos adversos , Peritonitis/veterinaria , Compuestos de Selenio/efectos adversos , Enfermedades de las Ovejas/inducido químicamente , Animales , Compuestos de Bario/administración & dosificación , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/efectos adversos , Inspección de Alimentos , Inyecciones Intraperitoneales/veterinaria , Carne/normas , Peritonitis/inducido químicamente , Peritonitis/patología , Pigmentación , Ácido Selénico , Selenio/deficiencia , Compuestos de Selenio/administración & dosificación , Ovinos , Enfermedades de las Ovejas/patologíaRESUMEN
Morphological and structural features of starch from potato (Solanum tuberosa) and rice (Oryza sativa) have been examined using atomic force microscopy. Amylose from potato and rice was observed in aggregated structures, which are suggested to be a result of retrogradation during sample preparation. The degrees of polymerization of amylose from potato and rice starches were calculated from the mean contour lengths of the observed structures to be approximately 1440 and 1860, respectively. Potato amylopectin appeared as a highly branched and extended molecule. Our results show that atomic force microscopy provides a useful method for examining the fine structural features and estimating the dimensions of starch molecules.