Bacterial septicemia and herpesvirus infection in Antarctic fur seals (Arctocephalus gazella) stranded in the São Paulo coast, Brazil.

In August 2021, two juvenile male Antarctic fur seals (Arctocephalus gazella) stranded in the southeastern Brazilian coast and were referred to rehabilitation centers. The animals presented increased body temperature, prostration, respiratory distress and despite treatment died. A necropsy following a standardized protocol was performed, and formalin-fixed tissues were processed for microscopic examination. Samples were screened for morbillivirus, herpesvirus, and Brucella spp. by molecular analyses (PCR, RT-PCR). Bacteriological culture was performed in samples collected from the lungs, trachea, and lymph nodes of both cases. The main histopathologic findings were of infectious nature, including multifocal necrotizing and fibrinous mixed interstitial pneumonia, bronchiolitis, and bronchitis, with intralesional myriad bacteria associated with vascular fibrinoid necrosis. Pseudomonas aeruginosa was isolated from tracheal and lung swabs of Case 1, and Klebsiella oxytoca was found in nostril swabs, tracheobronchial lymph nodes, and lung of Case 2. Gammaherpesvirus infection was detected in both cases, and the sequences retrieved were classified into the genus Percavirus. All tested samples were PCR-negative for Brucella spp. and morbillivirus. We hypothesize that the deficient immunological status in association with starvation predisposed the reactivation of herpesvirus and secondary bacterial co-infections. To the authors' knowledge, this is the first molecular detection of herpesvirus in an Antarctic pinniped. These findings reinforce that Otariid gammaherpesvirus circulating in the Southern Hemisphere are likely endemic in the Arctocephalus genus. This report contributes to the current knowledge of health aspects affecting wild pinnipeds, especially in the poorly studied Antarctic species.

Effects of ivermectin treatment during prepubertal and pubertal period on sexual parameters and sexual behavior in adulthood in rats.

Pediculosis is a parasitic disease that is considered a serious global public health problem. It is caused by the ectoparasite that is popularly known as lice, mainly affecting children in early childhood. The most commonly used treatment to combat this parasitosis is the macrocyclic lactone ivermectin (IVM). However, the use of IVM is contraindicated in children who are younger than 5 years old or who weigh <15 kg because some types of drugs that are used during certain periods of brain maturation can lead to behavioral disorders. The present study evaluated the effects of IVM treatment during the prepubertal and pubertal period on sexual behavior in adulthood in male rats. Genital grooming, preputial separation, sexual behavior, sexual motivation, relative organ weight, the gonadosomatic index, and histopathology were evaluated. Oral dose of 0.2 mg/kg (therapeutic dose) of a commercial IVM formulation was administered. IVM affected genital grooming but did not influence preputial separation in prepubertal rats. Prepubertal IVM administration did not impair sexual behavior in adult rats, with the exception of the time of residence with female rats in the sexual motivation test. It did not affect relative organ weights, with the exception of the relative weight of the full seminal vesicle. It did not alter the gonadosomatic index, and no histopathological alterations were observed in different organs. These results indicate that administration of a therapeutic dose of IVM during the prepubertal and pubertal period does not alter parameters of sexual development or sexual behavior in adult male rats.

Pathological Findings in Lowland Tapirs (Tapirus terrestris) Killed by Motor Vehicle Collision in the Brazilian Cerrado.

The lowland tapir (Tapirus terrestris) is the largest land mammal in South America. The species faces steady population decline due to poaching, habitat loss and fragmentation, road-kill, pesticide pollution, competition with domestic livestock and fires, among other threats. The lowland tapir is currently listed as vulnerable to extinction. Little information is available about natural disease processes for the species. This study aimed to report the pathological findings recorded in a cohort of 35 lowland tapirs killed by motor vehicle collision (MVC) on highways of Mato Grosso do Sul State, Brazil, between 2015 and 2018. The main gross pathological findings were those associated with MVC, primarily involving skeletal fractures and internal multiorgan damage with extensive bleeding and/or severe central nervous system injury. The most prevalent concurrent histopathological findings, unrelated to the cause of death, were: adrenal gland degeneration, necrosis and loss of fascicular and reticular cells with replacement fibrosis and cortical atrophy (9/15; 60%); interstitial pneumonia (20/34; 59%); glossitis (9/24; 38%); pulmonary anthracosis (12/34; 35%); colitis (9/28; 32%); and cholangitis/pericholangitis (9/35; 26%). The aetiopathogeneses and clinicopathological significance of some of these findings are unclear; however, parasitic infections appear to be common. Our results highlight the importance of wildlife health information obtained through the study of carcasses of roadkills.

Ivermectin does not interfere with seminal and hormonal parameters in male rabbits.

Ivermectin (IVM) is a macrocyclic lactone used as a broad spectrum antiparasitic agent against nematodes and arthropods. It is mainly used in the control of parasitic infections of domestic animals, and recently has been used in humans to treat onchocerciasis, scabies, and pediculosis. In mammals, evidence has indicated that macrocyclic lactones interact with gamma-aminobutyric acid (GABA)-mediated chloride channels. The GABAergic system is known to be involved in the manifestation of sexual behavior, and previous studies have shown that IVM impaired sexual behavior in both male and female rats. Thus, considering that IVM may interfere with the sexual sphere, this study evaluated the temporal (1 up 60 days) effects of exposure to IVM (0.2 and 1.0 mg/kg, administered subcutaneously) on seminal and hormonal parameters of male rabbits. In male rabbits, the spermatozoa concentration, motility and morphology, the integrity of the plasmatic, acrosomal and mitochondrial membranes of the spermatozoa, the organ weights, gonadosomatic index, serum testosterone concentrations, histopathological findings were evaluated and hematological and serum biochemical analysis was conducted. No changes were observed in male seminal parameters evaluated by spermatozoa concentration, motility, and morphology, nor the potential for fertilization evaluated by the integrity of the plasmatic, acrosomal, and mitochondrial membranes of the spermatozoa; there was also no interference in serum testosterone concentration, serum biochemistry and hematological parameters. The findings of this study using the artificial vagina for collection of semen and computer-assisted semen analysis showed that IVM at doses of 0.2 and 1.0 mg/kg of SC did not alter any of the semen parameters of rabbits evaluated for up to 60 days after administration.

Intrafamilial correlation analysis for IgM serum levels.

The IgM serum level was determined in the members of 29 healthy families. The IgM mean concentrations between fathers and mothers and between sons and daughters were significantly different (P less than .01), with higher serum IgM levels in females than in males. Simple linear regression analysis was done for the following intrafamilial combinations: son-father, daughter-father, son-mother, and daughter-mother. Significant correlation coefficients (P less than .05) were obtained in all four combinations, which does not support the X-linked gene hypothesis (i.e., that the X chromosome carries quantitative genes for immunoglobulin M). An alternative explanation for the differences between sexes for IgM serum concentration is considered.