Prototheca bovis in goats: Experimental mastitis and treatment with polypyrrole.

Prototheca bovis has been associated with several cases of mastitis in cattle but no record of intramammary infections has been reported in goats. This infection does not respond to available treatments and the disposal recommendation of affected animals cause great damage to the dairy industry. Alternatives for dealing with infections caused by Prototheca spp. are required worldwide. In vitro results suggest polypyrrole as promising molecule for combating this alga, because an algaecide effect was observed on tested Prototheca spp. isolates. Thus, this study evaluated goats as an experimental model for intramammary infection by P. bovis and a protocol for treating these animals with an intramammary polypyrrole solution. The possibility of P. bovis promoting an intramammary infection in goats was experimentally proven, demonstrating this species as an important model for studies involving algae mastitis. Furthermore, polypyrrole reduced the counts of Prototheca sp. in the analyzed samples, showing potential to fight this microorganism also in vivo. The results obtained in this study demonstrate the ability of P. bovis to colonize breast tissue in lactating goats and the highly soluble molecule of polypyrrole has potential use for the treatment of protothecosis.

Gastrointestinal helminths in dogs: occurrence, risk factors, and multiple antiparasitic drug resistance.

Helminth infections are detrimental to the overall health of dogs; therefore, this study aimed to identify antiparasitic-resistant helminths and evaluate the infection rate and risk factors for parasitism in canines. For this purpose, a parasitological evaluation of 38 randomly selected animals was performed, followed by the evaluation of the anthelminthic efficacy of three drugs: pyrantel pamoate with praziquantel (Canex Composto®), fenbendazole (Fenzol Pet®), and milbemycin oxime with praziquantel (Milbemax C®). Among the evaluated animals, 22/38 (57.89%) tested negative and 16/38 (42.71%) tested positive for Ancylostoma caninum infection. Evaluation of the efficacy of antiparasitic drugs showed that 12/16 (75%) dogs were infected with helminths that were susceptible to pyrantel pamoate with praziquantel. Among those for which pyrantel pamoate with praziquantel was not effective, 3/4 (75%) were susceptible to fenbendazole, while the remaining case resistant to both pyrantel pamoate with praziquantel and fenbendazole was sensitive to milbemycin oxime with praziquantel (100%). The odds ratio of infection in dogs inhabiting environments containing soil or grass was 6.67 times higher than that in dogs inhabiting impermeable environments. Mixed-breed dogs (SRD) were 6.54 times more likely to be infected compared to purebred dogs. A. caninum resistant to pyrantel pamoate with praziquantel (4/16, 25%) and fenbendazole (1/4, 25%) were detected. The results of this study demonstrated the importance of coproparasitological monitoring by professionals before and after treatments to assess antiparasitic drug effectiveness, ensure animal health and welfare, and minimize animal exposure to risk factors.

Vaccinia viruses isolated from cutaneous disease in horses are highly virulent for rabbits.

Two genotypically distinct Vaccinia viruses (VACV), named P1V and P2V, were isolated from an outbreak of cutaneous disease in horses in Southern Brazil. We herein investigated the susceptibility of rabbits, a proposed animal model, to P1V and P2V infection. Groups of weanling rabbits were inoculated intranasally (IN) with P1V or P2V at low (10(2.5) TCID50), medium (10(4.5)TCID50), or high titer (10(6.5)TCID50). Rabbits inoculated with medium and high titers shed virus in nasal secretions and developed serous to hemorrhagic nasal discharge and severe respiratory distress, followed by progressive apathy and high lethality. Clinical signs appeared around days 3-6 post-inoculation (pi) and lasted up to the day of death or euthanasia (around days 5-10). Virus shedding and clinical signs were less frequent in rabbits inoculated with low virus titers. Viremia was detected in all groups, with different frequencies. Viral DNA was detected in the feces of a few animals inoculated with P1V and P2V, low titer, and with P2V at high titer. Gross necropsy findings and histological examination showed diffuse interstitial fibrousing pneumonia with necrosuppurative bronchopneumonia and intestinal liquid content. Neutralizing antibodies were detected in all inoculated animals surviving beyond day 9 pi. These results show that rabbits are highly susceptible to VACV isolated from horses, and develop severe respiratory and systemic disease upon IN inoculation. Thus, rabbits may be used to study selected aspects of VACV infection and disease.