Histomorphological study of the preputial and clitoral glands in BALB/c mice with experimental Taenia crassiceps infections.

Male preputial and female clitoral glands of mice undergo development that depends on the level of hormones in the animal. Experimental infection with Taenia crassiceps cysticerci results in significant physiological modifications in the host. Here, we investigated the histomorphological alterations induced by the parasite in these pheromonal glands. Preputial and clitoral glands were recovered from mice at 15, 35, 50, and 70 days postinfection (DPI). The glands were examined macroscopically and microscopically after histological preparation. Male preputial glands show a marked atrophy 35 days after infection. This atrophy is the result of a disorganization of the acinus tissue structure. During the course of infection, the basal, intermediate, and mature acinar cell layers are reduced, and finally, at 70 DPI, the gland includes only the duct system and fibrotic structures. In contrast, females are not affected by the infection because no modifications were observed in the morphology or histology of the clitoral glands. A probable cause for such a divergence between infected male and female mice might be related to a sex steroid imbalance as described during T. crassiceps infection.

Behavioural dominance and Taenia crassiceps parasitism in BALB/c male mice.

Behavioural dominance relationships in mouse populations are based upon fighting and antagonistic behaviour. Social rank is affected by the physiological states present in the mice. Experimental infection by Taenia crassiceps cysticerci induced physiological disorders and disrupted the dominant-subordinate status. Infected male mice showed strong perturbations in territorial behaviour and aggressiveness. Infected dominant male mice did not show a significant reversal of dominance order compared to uninfected mice. In addition, during confrontation between naive infected and healthy mice, infected animals more often assumed a subordinate status than healthy ones. The effects of the infection by T. crassiceps were more likely to prevent adult male mice from becoming behaviourally dominant than to reverse existing dominance relationships. The results are discussed on the basis of the parasite manipulation hypothesis and host optimal foraging and decision-making theories.

Characterization of cDNA encoding a L37a ribosomal protein from Taenia crassiceps and its potential use in phylogenetic reconstructions.

In this study, we characterized for the first time the complete sequence of a L37a cDNA from a cestode specie: Taenia crassiceps. A phylogenetic analysis of L37a ribosomal proteins from distant animal species is presented and the potential use of such proteins in molecule-based phylogeny is discussed.