The structure of the penis with the associated baculum in the male greater cane rat (Thryonomys swinderianus)

In this study, the structures of penises of eight sexually mature male greater cane rats were examined at both macroscopic and histological levels. Each animal was sacrificed after anaesthesia with ether and then dissected open with the penis exposed from its root. The penises were first grossly examined, measured, and then prepared for histological examination. From this study it was observed that the body size has no allometry with penile size, but the testicular weight correlated with Os penis length in the greater cane rat. Grossly, the penis which was whitish in colour, with a mean length of 5.46 ± 0.36 cm, has no obvious collum penis but a flexura that turns it caudo-ventral and separates the corpus and glans penis. There was the presence of cornified papillae covering parts of the corpus and glans penis as well as a blind sac sacculus urethralis under the urethra on the glans penis. Histologically, the corpora cavernosa penis were completely separated by a connective tissue septum which sent the trabeculae network into the cavernous tissues and replaced the caverns as it moves from corpus to glans penis. The Os penis formed through endochondral ossification after 42 months of age in this animal. Therefore, from a histological standpoint, the cane rat penis belongs to the intermediate type. In conclusion, these findings provide vital information on the penile anatomy of the greater cane rat, which will serve as a basis for comparing penile morphology among the suborder hystricomorpha and expand knowledge of the reproductive biology in this animal. (Folia Morphol 2011; 70, 3: 197–203

Comparative study on the sensitivity of bacteriology and immunohistochemical technique in the diagnosis of natural salmonellosis in chickens

Bacteriological and immunohistochemical diagnoses of natural salmonellosis in chickens were carried out on 36 cases, in order to compare the sensitivities of the two techniques. Samples of the lungs, heart, liver, spleen, kidneys, proventriculus, intestine and caecum were collected at postmortem for bacterial isolation and separately fixed in 10% formalin for immunohistochemistry. The frequencies of Salmonella isolation by bacteriology and antigen detection by immunohistochemical technique were determined from the tissue samples and overall percentages between the two were compared. Out of 36 cases of natural salmonellosis, 53 Salmonella isolates were obtained from different organs in 31 (86.1%) cases; 48 isolates from 28 (77.8%) cases tested biochemically positive; PCR confirmed 41 isolates from 25 (89.3%) cases. Immunohistochemical test was positive in all the 36 (100%) cases. In the present study, immunohistochemical technique was more sensitive than isolation and identification and can be used as an adjunct to bacteriology in the diagnosis of avian salmonellosis.Keywords: Salmonellosis, Diagnosis, Bacteriology, Immunohistochemistry, Postmortem, Chicke