Small-scale environmental enrichment and exercise enhance learning and spatial memory of Carassius auratus, and increase cell proliferation in the telencephalon: an exploratory study

Carassius auratus is a teleost fish that has been largely used in behavioral studies. However, little is known about potential environmental influences on its performance of learning and memory tasks. Here, we investigated this question in C. auratus, and searched for potential correlation between exercise and visuospatial enrichment with the total number of telencephalic glia and neurons. To that end, males and females were housed for 183 days in either an enriched (EE) or impoverished environment (IE) aquarium. EE contained toys, natural plants, and a 12-hour/day water stream for voluntary exercise, whereas the IE had none of the above. A third plus-maze aquarium was used for spatial and object recognition tests. Different visual clues in 2 of its 4 arms were used to guide fish to reach the criteria to complete the task. The test consisted of 30 sessions and was concluded when each animal performed three consecutive correct choices or seven alternated, each ten trials. Learning rates revealed significant differences between EE and IE fish. The optical fractionator was used to estimate the total number of telencephalic cells that were stained with cresyl violet. On average, the total number of cells in the subjects from EE was higher than those from subjects maintained in IE (P=0.0202). We suggest that environmental enrichment significantly influenced goldfish spatial learning and memory abilities, and this may be associated with an increase in the total number of telencephalic cells.

Undifferentiated carcinoma of the pancreas in a cockatiel (Nymphicus hollandicus): case report / Carcinoma indiferenciado de pâncreas em calopsitas (Nymphicus hollandicus): relato de caso

Undifferentiated carcinoma of the pancreas is a malignant neoplasm that is uncommon among domestic species, especially cockatiels (Nymphicus hollandicus), one of the most popular birds kept as a pet throughout the world. The aim of this study was to describe the occurrence of an undifferentiated carcinoma in the pancreas of a cockatiel. A bird, an adult male that died naturally with swelling in the abdominal region, was referred to necropsy. Macroscopic examination showed poor body condition, the coelomic cavity filled with liquid and a white mass attached to the pancreas and other smaller masses attached to the duodenum. Tissue samples and organs were harvested and fixed in 10% buffered formalin, then routinely processed for histopathology and stained with hematoxylin and eosin. Microscopic analysis demonstrated an epithelial neoplasia with a predominantly solid pattern, lymphatic invasion and involvement of the intestinal serous membrane. These findings indicate the occurrence of an undifferentiated pancreatic carcinoma in a cockatiel that was diagnosed by histopathology.(AU)

O carcinoma indiferenciado de pâncreas é uma neoplasia maligna, incomum entre as espécies domésticas, especialmente em calopsitas (Nymphicus hollandicus), uma das aves mais populares como animal de companhia no mundo. O objetivo deste trabalho foi descrever a ocorrência de carcinoma indiferenciado de pâncreas em Nymphicus hollandicus. Uma ave, macho adulto, com morte natural e com aumento de volume em região abdominal, foi encaminhada para necropsia. Ao exame macroscópico foram observados mau estado corporal, cavidade celômica repleta de líquido e massa esbranquiçada aderida ao pâncreas e outra menor aderida ao duodeno. Amostras de tecidos e órgãos foram colhidas em formol 10% tamponado, processadas rotineiramente para histopatologia e coradas por hematoxilina e eosina. Na microscopia foi observada neoplasia epitelial com padrão predominantemente sólido, com invasão linfática e implantação na serosa intestinal. Com esses achados, comprovou-se a ocorrência de carcinoma indiferenciado de pâncreas em Nymphicus hollandicus, o qual pode ser diagnosticado por meio de histopatologia.(AU)

Inclusões intracitoplasmáticas hialinas na medular da adrenal de bovinos / Intracytoplasmic hyaline inclusions in adrenal medulla of bovine

Cytoplasmic inclusion bodies in adrenal medullary chromaffin cells have been described in various species including humans. These inclusions are believed to be related to certain infectious, toxic and neurodegenerative diseases. No reports concerning such adrenal inclusions have been described in bovines. Adrenal glands from twenty bovines were evaluated in a retrospective study. Seven of these exhibited inclusions - three cases of rabies, two cases of chronic suppurative bronchopneumonia, one case of chronic suppurative peritonitis, and one case of gangrenous mastitis. The inclusions were present in higher numbers especially in cases of rabies and also in one case of chronic suppurative bronchopneumonia. The inclusions were intracytoplasmic, eosinophilic, rounded, single or multiple, of various sizes, strongly stained by PAS and were present in higher numbers in the external layer of the adrenal medulla. The inclusions were negative when subjected to immunohistochemistry for detection of viral antigens in the cases of rabies. Although inclusion bodies were present in adrenal glands devoid of other histological alterations, they were more abundant in cases in which the adrenal gland had other alterations. The correlation between certain diseases and the development of inclusion bodies is not known, which highlights the importance of further studies on these inclusions in adrenal glands of bovines.