ABSTRACT
SUMMARY: This study aimed to investigate the microstructure and ultrastructure of the Bursa cloacalis (Bursa of Fabricius) (BC) in young Leiothrix lutea at various days of age (a few days after hatching) using light microscopy and transmission electron microscopy. The bird BC was sampled at 1, 5, 7, and 9 days of age. Immediately after dissection, the structure and integrity of the BC (not degenerative) were retained and the specific temporal features could be visualized precisely. After hematoxylin-eosin staining and uranyl acetate/lead citrate staining, the microstructure and ultrastructure of the BC, respectively, could be observed clearly. The microscopic observations revealed the following: in addition to change in the size of BC or lymphoid follicles, many cavities were found in the BC; the distribution of the lymphoid follicles in Leiothrix lutea was different from that in other birds; and the segregating line between the bursal cortex and medulla became increasingly clear as the age increased. In conclusion, the structural data obtained in this study provides a better understanding of the specific immunological function of the BC in Leiothrix lutea.
RESUMEN: Este estudio tuvo como objetivo investigar la microestructura y ultraestructura de la Bursa cloacalis (BC) en Leiothrix lutea joven unos días después de la eclosión, utilizando microscopía óptica y microscopía electrónica de transmisión. La BC se muestreó a los 1, 5, 7 y 9 días de edad del Leiothrix lutea. Inmediatamente después de la disección, se observó la estructura y la integridad de la CB (no degenerativa) y se pudo visualizar con precisión las características temporales específicas. Después de la tinción con hematoxilina-eosina y con acetato de uranilo /citrato de plomo, pudimos observar claramente la microestructura y ultraestructura de la BC. Las observaciones microscópicas revelaron el cambio en el tamaño de la CB o de los folículos linfoides y además, se encontraron numerosas cavidades en la CB; la distribución de los folículos linfoides en Leiothrix lutea era diferente a la de otras aves; y la línea de segregación entre la corteza bursal y la médula se hizo cada vez más clara a medida que aumentaba la edad. En conclusión, los datos estructurales obtenidos en este estudio proporcionan una mejor comprensión de la función inmunológica específica de la Bursa cloacalis en Leiothrix lutea.
Subject(s)
Animals , Bursa of Fabricius/ultrastructure , Passeriformes/anatomy & histology , Lymphoid Tissue/ultrastructure , Microscopy/methodsABSTRACT
ABSTRACT: This study discusses the causes of bird deaths recorded in a small aviary dedicated to the breeding of a few exotic, wild bird species. Findings from 28 birds were examined over a period of five years. About 40% of the deaths occurred in the first two weeks after hatching in the two most numerous species in the flock and such losses were mainly a result of starvation caused by inadequate nutritional management. Additionally, 28% of the cases affected recently introduced birds. Despite frequent treatment with anthelmintics; a total of 21% of the deaths in the flock could be attributed to parasitic diseases, most of them in recently acquired birds. Only three of the deaths could be associated with advanced age, all of the further cases were also attributable to management fails. Our results indicated that propagation of these and other species requires an improvement of the management of the newly hatched and newcomer birds to considerably enhance the flock’s performance. Such information may be useful in conservation initiatives and may justify, at least in part, captivity of these animals.
RESUMO: Este estudo discute as causas de morte de aves registradas em um pequeno criadouro de umas poucas espécies de aves silvestres exóticas. As mortes de 28 aves foram examinadas em um período de cinco anos. Cerca de 40% dos casos ocorreram na primeira semana de vida de filhotes das duas espécies mais numerosas no plantel e essas perdas foram consequentes à desnutrição por falhas no manejo nutricional. Outros 28% de casos ocorreram em aves, recentemente introduzidas, ou em fase de adaptação, no criadouro. Ainda que as aves do plantel sejam frequentemente dosificadas com anti-helmínticos, 21% das mortes no plantel foram secundárias a doenças parasitárias; a maioria afetou aves recentemente adquiridas. Exceto por três mortes que foram associadas com desordens atribuídas à idade avançada, todas as demais foram associadas com inadequações no manejo das aves. Esses resultados sugerem que, em sistemas dessa natureza, as aves recém-nascidas e as recém-introduzidas são categorias críticas que demandam concentração de esforços para o atendimento sistemático de suas necessidades. Tais dados podem ser aplicáveis em iniciativas de conservação de outras espécies e podem justificar, ainda que parcialmente, a manutenção desses animais, em cativeiro.