The aim of the present study was to describe an outbreak of atypical interstitial pneumonia affecting 15 Angus cattle aged 7-30 months in the south of Rio Grande do Sul. The clinical course of the disease was approximately 1-3 days. The cattle were kept in the native field and had received feed containing the remains of wafers from a food factory before the outbreak. Clinical signs included dyspnea and abdominal breathing, with a clinical evolution period of up to 3 days. Nine animals presented apathy and respiratory difficulty and died within 24h, while three animals exhibited a clinical evolution period of 36-48h. Three other animals died without any clinical signs. The main macroscopic lesions were observed in the lungs, which did not collapse at the opening of the thoracic cavity and showed a rubbery consistency. On the cut surface, the organs were firm and dark red, with marked distension of the interlobular septa due to edema. Histopathological analysis revealed thickening of the interlobular pulmonary septa; interstitial edema and emphysema; mild mononuclear cell, eosinophil, and neutrophil infiltration; areas of type II pneumocyte proliferation, and thickening of the alveolar walls. Fibrin was observed in the alveolar lumen with the formation of hyaline membranes. On the basis of macroscopic and histological examinations and epidemiological data, a final diagnosis of atypical interstitial pneumonia was made. Although, the cause of the disease has not been identified, it is believed that the bran wafer meal contained ingredients that were not suitable for animals, consequently triggering the disease.

The causes of death of cattle kept in pre-export feedlots (PEFs) and in feedlot for finishing for slaughter are described. Two studies were conducted: a retrospective study of mortality cases in feedlots from 2000 to 2017 registered at the “Laboratório Regional de Diagnóstico” of the “Faculdade de Veterinária” of the “Universidade Federal de Pelotas”; and a prospective study from January 2018 to August 2019, following up 22 feedlots for finishing and six PEFs for the export of live cattle. From January 2000 to August 2019 samples of 150 cases of diseases that affected feedlot cattle were received from 22 feedlots for finishing and 115 of the six PEFs followed. Mortality considering all diagnosed diseases was significantly higher in feedlots for finishing (p<0.05), than in PEFs for the export of live cattle, of 1% and 0.12%, respectively. Diseases of the digestive system were the most important causes, of death in feedlots regardless of its purpose. Acidosis presented the highest mortality rates both in feedlot for finishing (3.33%) as in PEFs for export (0.95%). In all cases the disease occurred due to failure in the adaptation of animals to the ingestion of concentrated foods. Bovine tick fever and pneumonia presented mortality rates of 0.13% and 0.09%, respectively in PEFs. In the feedlot for finishing seneciosis was the second cause of death due to cattle coming from areas with high infestation by the plant. In the present study, it was possible to identify the main diseases that occur in cattle feedlots for finishing or for the export of live animals in the southern region of Rio Grande do Sul. These diseases are known in other systems of cattle breeding and can be prevented or controlled through management, chemoprophylaxis or vaccination, minimizing losses due to mortality.

In this study we describe the epidemiology, clinical signs, and pathology of an outbreak of avian aspergillosis in alternative breeding in the southern region of Rio Grande do Sul, Brazil. Between the fifth and tenth day of life, 360 chicks from a flock of 4000 developed unspecific clinical signs and died. The birds were housed in a reused aviary litter, without previous treatment. In 11 six-day-old female ISA Brown chicks (Gallus gallus domesticus), necropsy revealed firm, yellowish-white, multinodular lesions extending from the pleura to the lung parenchyma. Histologically, a granulomatous, multifocal to coalescent pneumonia was observed. Granulomas were characterized by central necrosis, with heterophil and epithelioid macrophage infiltration and presence of countless Y-shaped intralesional septate hyphae morphologically compatible with Aspergillus spp. The diagnosis through isolation confirmed Aspergillus fumigatus. We highlight the importance of aspergillosis as a primary cause of diseases in the respiratory tract of young birds in alternative breeding. Measures to prevent aspergillosis mainly regarding the reuse of aviary litter are essential in poultry husbandry to prevent economic losses, reduce environmental contamination and mitigate the potential risk to public health.

RESUMO: Babesiose cerebral é uma enfermidade causada pelo protozoário Babesia bovis. O agente faz parte do complexo Tristeza Parasitária Bovina, uma das mais importantes doenças parasitárias em bovinos. O presente estudo relata um surto causado por B. bovis em vinte bezerros de aproximadamente 7 a 25 dias de idade. O surto ocorreu entre março e junho de 2015, na região sul do Brasil, área de instabilidade enzoótica para a Tristeza Parasitária Bovina. O diagnóstico foi realizado pela epidemiologia, lesões macroscópicas e pela presença de numerosas formas parasitárias de Babesia bovis em capilares encefálicos, observados em imprints corados por Giemsa. Surtos de babesiose por B. bovis cerebral nos primeiros dias de vida de bezerros é incomum, porém não pode ser desconsiderada em surtos com alta letalidade em áreas de instabilidade enzoótica.

Hydatidosis and cysticercosis are parasitoses caused by the larval forms of the cestodes Equinococcus spp. and Taenia spp., which belong to the Taeniidae family. Their definitive hosts are canids and humans, respectively, with ruminants as the intermediate hosts and humans as an accidental host of both diseases. These parasites are responsible for large economic losses in slaughterhouses due to condemnation of carcasses and by-products. The present study reports the mean incidence rates of hydatidosis and cysticercosis in cattle slaughtered in the southern region of Rio Grande do Sul state, Brazil. The incidence rates observed between 2013 and 2016 were 19.96% and 0.9%, respectively, with decreased tendency of occurrence of both diseases in those years. Despite the downward tendency of the diseases, hydatidosis presented high incidence. Hydatidosis performance over the years was characterized by significant increase in the number of cases, followed by marked decrease. Cysticercosis presented a decrease in number of cases at the beginning and the end of each year. These diseases have a significant socioeconomic impact as they are responsible for large losses in the livestock industry, due to reduced productivity and carcass condemnation, and represent a risk to public health.

Background: A listeriosis outbreak in a sheep fattening feedlot in the Southern Region of Rio Grande do Sul State, Brazil is described. This disease is caused by Listeria monocytogenes and represents a risk to public health since it affects not only ruminants but also humans. This agent is widely spread in the environment, such as in the soil and water. It is also found in decaying vegetable matter and the feces and fluids of domestic animals. The aim of this study was to describe a listeriosis outbreak in sheep raised in feedlots, its epidemiology, and to establish the importance of this disease in this type of sheep management system, evaluate the possible sources of infection, and suggest ways to control it.Cases: Sheep were kept in a 2-sector shed, one with east solar orientation and the other with west solar orientation, the latter with free access to domestic birds. Sheep were fed silage and concentrate. Seven sheep were affected, 5 died and 2 recovered. Clinically, the sheep displayed loss of balance, excessive drooling, and tremors; one exhibited circling, head deviation, apathy, nystagmus, lateral recumbency, paddling, and labored breathing. At necropsy, macroscopic lesions were not found, and histologically several micro-abscesses and perivascular cuffs with lymphocytes, macrophages, and neutrophils were present in the brain stem. Listeria monocytogenes suspected colonies were observed in the microbiological culture, and the bacteria was identified by biochemical analysis. The immunohistochemistry test in brain stem sections was positive for the antibody BD DifcoTM Listeria O Antiserum Poly Serotypes 1 and 4.Discussion: A listeriosis outbreak in a feedlot sheep was confirmed through epidemiological findings, histological lesions, bacterial culture, and immunohistochemistry analysis. This infection is frequent in sheep fed silage of poor quality or other food with improper storage and lack of hygiene. In the present outbreak, the bacteria were isolated from silage. However, it is likely that domestic birds, which were raised in the same place and had free access to the west sector of the feedlot, were the initial source of infection, because the sheep from the opposite sector (east) did not get ill. The disease caused by environmental contamination or through contact with fluids and feces of ducks, chickens, cattle, and pigs has already been described in outbreaks that occurred in the central region of Rio Grande do Sul. Sheep aggregation in feedlot systems is also a favorable factor for the development of the bacteria and the occurrence of outbreaks because the accumulation of feces and urine cause humidity on the stalls. This allows outbreaks to occur in other seasons of the year, such as in the outbreak reported herein. The exchange of silage that served as food for sheep was another control measure, and new cases were not reported 8 months after these procedures were taken. In the outbreak studied, 2 sheep that exhibited clinical signs were treated with oxytetracycline and recovered. Some authors report that treatment for listeriosis is inefficient because neurological lesions are irreversible. Nonetheless, other studies have reported the recovery of some animals when they were treated with oxytetracycline or a combination of oxytetracycline and dexamethasone or ampicillin and gentamicin like in the outbreak described in this paper.Keywords: Listeria monocytogenes, central nervous system, silage, feedlot, ovine.

No abstract

This study aimed to verify the occurrence of Dioctophyme renale in stray dogs in the city of Pelotas, in the state of Rio Grande do Sul, Brazil. The Laboratório Regional de Diagnóstico of the Universidade Federal de Pelotas received 146 wandering dogs for necropsy, sent by the City Hall of Pelotas from March 2012 to January 2020. Among the necropsied animals, seventeen dogs (11.64%) were diagnosed with dioctophymosis. Among these dogs, 11 were parasitized with one specimen in the right kidney, two dogs presented two specimens in the right kidney, and in other two dogs, the parasites were in the abdominal cavity. In one dog, two parasites were found in the left kidney; in another dog, both kidneys were parasitized, with two parasites in the right kidney and one in the left kidney. The data obtained in this study showed that the occurrence of D. renale in stray dogs in the city of Pelotas is high, and D. renale mainly parasitizes the right kidney.