Severe diarrhea outbreak in beef calves (Bos indicus) caused by G6P[11], an emergent genotype of bovine rotavirus group A

The episodes of diarrhea caused by neonatal bovine rotavirus group A (BoRVA) constitute one of the major health problems in the calf rearing worldwide. The main G (VP7) and P (VP4) genotypes of BoRVA strains involved in the etiology of diarrhea in calves are G6P[1], G10P[11], G6P[5], and G8P[1]. However, less frequently, other G and P genotypes have been described in BoRVA strains identified in diarrheic fecal samples of calves. This study describes the identification and molecular characterization of an emerging genotype (G6P[11]) in BoRVA strains involved in the etiology of a diarrhea outbreak in beef calves in a cattle herd of high production in extensive management system. The diarrhea outbreak, which showed high morbidity (60%) and lethality (7%) rates, occurred in calves (n= 384) Nelore (Bos indicus) up to 30-day-old from the State of Mato Grosso do Sul, Brazil. BoRVA was identified in 80% (16/20) of the fecal samples analyzed by polyacrylamide gel electrophoresis (PAGE) technique. In all PAGE-positive fecal samples were amplified products with 1,062-bp and 876-bp in the RT-PCR assays for VP7 (G type) and VP4 (VP8*) (P type) of BoRVA, respectively. The nucleotide sequence analysis of VP7 and VP4 genes of four wild-type BoRVA strains showed G6-III P[11]-III genotype/lineage. The G6P[11] genotype has been described in RVA strains of human and animal hosts, however, in calves this genotype was only identified in some cross-sectional studies and not as a single cause of diarrhea outbreaks in calves with high morbidity and lethality rates as described in this study. The monitoring of the G and P genotypes of BoRVA strains involved in diarrhea outbreaks in calves is important for both animal and public health by allowing the identification of the most frequent genotypes, the characterization of novel genotypes and to identify reassortments with genotypes described in animal and human hosts. The results of this study show the importance of the monitoring of the genotypes of BoRVA strains involved in episodes of bovine neonatal diarrhea as for characterization of frequency of occurrence and pathogenic potential of uncommon genotypes as for monitoring of the emergency of different BoRVA genotypes not included in commercial vaccines

Diarrhea outbreaks in suckling piglets due to rotavirus group C single and mixed (rotavirus groups A and B) infections

Porcine group A rotavirus (PoRVA) is a major cause of neonatal diarrhea in suckling and recently weaned piglets worldwide. The involvement of non-group A rotavirus in cases of neonatal diarrhea in piglets are sporadic. In Brazil there are no reports of the porcine rotavirus group C (PoRVC) as etiologic agent of the diarrhea outbreaks in piglets. The aim of this study was to describe the identification of rotavirus group C in single and in mixed infection with rotavirus groups A and B in three neonatal diarrhea outbreaks in suckling (<21-day-old) piglets, with 70% to 80% and 20% to 25% of morbidity and lethality rates, respectively, in three pig herds located in the state of Santa Catarina, Brazil. The diagnosis of PoRV in the diarrheic fecal samples was performed using polyacrylamide gel electrophoresis (PAGE) to identify the presence of porcine rotavirus groups A, B (PoRVB), and C, and by RT-PCR (PoRVA and PoRVC) and semi-nested (SN)-PCR (PoRVB) to partially amplify the VP4 (VP8*)-VP7, NSP2, and VP6 genes of PoRVA, PoRVB, and PoRVC, respectively. One RT-PCR (PoRVA and PoRVC) and SN-PCR (PoRVB) product of each group of rotavirus of each diarrhea outbreak was submitted to nucleotide (nt) sequence analysis. Based on the PAGE technique, 4 (25%) and 1 (6.25%) of the 16 diarrheic fecal samples evaluated in the first outbreak presented PoRVA and PoRVC electropherotype, respectively, and 11 (68.75%) were negative. In the second outbreak, 3 (42.85%) of the 7 fecal samples evaluated presented PoRVA electropherotype, and in 3 (42.85%) and in 1 (14.3%) fecal samples were detected inconclusive and negative results, respectively. Three (30%) of the 10 fecal samples of the third outbreak presented PoRVC electropherotype; 5 (50%) and 2 (20%) samples showed negative and inconclusive results, respectively. Based on the RT-PCR and SN-PCR assays in the first neonatal diarrhea outbreak, PoRVC was detected in 13 (81.2%) of the 16 diarrheic fecal samples evaluated. PoRVC single infection was identified in 4 (25%) of these samples and mixed infections with PoRVA and PoRVB in 9 (56.2%) fecal samples. All of the seven diarrheic fecal samples evaluated from the second neonatal diarrhea outbreak were positive for PoRVC, whereas its mixed infection with other PoRV groups was detected in 4 (57.2%) samples. In the third outbreak, PoRVC in single infection was detected in all of the 10 diarrheic fecal samples analyzed. In the nt sequence analysis, the PoRVA strains of the first and second outbreaks demonstrated higher nt identity with G4P[6] and G9P[23] genotypes, respectively. The PoRVB strains (first and second outbreaks) and the PoRVC strains (first, second, and third outbreaks) showed higher nt identity and clustered in the phylogenetic tree with PoRVB and PoRVC strains that belong to the N4 and I1 genotypes, respectively. This is the first description in Brazil of the involvement of PoRVC in the etiology of diarrhea outbreaks in suckling piglets. The results of this study demonstrated that PoRVC, in both single and mixed infections, is an important enteropathogen involved in neonatal diarrhea outbreaks in piglets and that the use of more sensitive diagnostic techniques allows the identification of mixed infections involving two or even three groups of PoRV, which may be more common than previously reported

Neonatal diarrhea by bovine coronavirus (BCoV) in beef cattle herds

O coronavírus bovino (BCoV) é o segundo mais importante agente etiológico viral envolvido em diarreias neonatais em bezerros de todo o mundo. Os relatos sobre a frequência da infecção por BcoV em rebanhos bovinos de corte criados extensivamente são incomuns no Brasil. Este estudo analisou 93 amostras fecais diarreicas de bezerros de corte com até 60 dias de idade, provenientes de 13 rebanhos comerciais distribuídos nos estados de Mato Grosso, Mato Grosso do Sul, Minas Gerais, Paraná e Rondônia. As amostras fecais foram colhidas no período de 2009-2012 e haviam sido previamente analisadas quanto à presença de rotavírus bovino grupo A (BoRVA), com resultados negativos. A presença do BCoV nas amostras fecais foi avaliada por meio da amplificação parcial do gene N pela técnica da semi-nested PCR. Em 33,3% (31/93) das amostras analisadas foi possível a amplificação de produtos com tamanho de 251 pb esperados para o BCoV. Os resultados deste estudo demonstraram que a coronavirose tem importante participação no complexo diarreia neonatal em rebanhos bovinos de corte criados extensivamente em várias regiões brasileiras.Bovine coronavirus (BCoV) is the second most important viral agent involved in neonatal diarrhea in calves worldwide. The reports on the frequency of BCoV infection in beef cattle herds under extensive management are uncommon in Brazil. The present study analyzed 93 diarrheic fecal samples of calves up to 60 days of age from 13 commercial beef cattle herds located in the states of Mato Grosso, Mato Grosso do Sul, Minas Gerais, Paraná, and Rondônia. The fecal samples were collected during 2009-2012 and were previously analyzed for the presence of bovine rotavirus group A (BoRVA), with negative results. The presence of BCoV in the fecal samples was evaluated by the partial amplification of the N gene by using the semi-nested PCR technique. The expected products of 251 bp length were amplified 33.3% (31/93) of the analyzed diarrheic fecal samples. The results revealed that coronaviruses has important participation in the neonatal diarrhea complex of beef cattle herds reared extensively from the different geographical regions of Brazil

Outbreak of neonatal diarrhea caused by multiple genotypes of rotavirus A in a beef calves herd

ABSTRACT: Calf diarrhea causes substantial economic losses to beef cattle production worldwide. It is a complex multifactorial pathological condition influenced by infectious, nutritional and environmental factors. The present study focused on analyzing the pathological and molecular characterization of bovine rotavirus A (BoRVA) during a diarrhea outbreak in a beef cattle herd located in the state of Mato Grosso, central-western region, Brazil. The outbreak caused high morbidity (80%) and mortality (12%) among 1,100 calves up to 30 days of age. The BoRVA was identified in 53.3% (16/30) of the diarrheic fecal samples analyzed using the silver-stained polyacrylamide gel electrophoresis (ss-PAGE) technique. The nucleotide sequence analysis of VP7 (G genotype) and VP4 (P genotype) via RT-PCR from eight BoRVA-positive fecal samples showed the genotypes G6P[5] (n = 6), G6P[11] (n = 1) and G6P[X] (n = 1). Three calves were necropsied and the gross findings included edema and thickened, wrinkled bowel mucosa in the small intestine. Microscopic lesions were confined to the villi of the small intestine, characterized mainly by villus fusion and moderate multifocal lymphoplasmacytic enteritis. Immunohistochemical examination of three cases was positive for BoRVA. The 53.3% of the diarrheic fecal samples that were positive for BoRVA in this study suggested that RV was the etiological agent involved in this neonatal calf diarrhea outbreak

The COVID-19 pandemic’s impact on the practices and biosecurity measures of veterinary medicine professionals in Brazil

Veterinarians, among other health professionals, are considered health professionals at high risk of exposure to and contraction of COVID-19. The main objective of this study is to assess changes in the clinical practices of veterinarians during the COVID-19 pandemic around prophylactic and biosafety measures, as well as to evaluate changes in workload and cost-benefit ratio. An online questionnaire was sent to veterinary professionals from July 2020 to July 2021 using Google Forms. A total of 1134 veterinarians answered the questionnaire on clinical experiences and biosafety practices during the COVID-19 pandemic. Veterinarians changed their routine clinical practices, as there was a reduction in working hours, and applied new patient approaches and advice to their owners, as well as restricting the number of people allowed inside. Biosafety measures were added in their workplaces, with an increase in the use of personal protective equipment. COVID-19 tests were administered at least once in 19.0%, and more than once in 9.5% of the respondents. Flu symptoms were present in 23.8% of the respondents, and 31.0% of the veterinarians attended to COVID-19 positive pet owners. Therefore, most veterinarians altered their routine practices, and some were exposed to sources of COVID-19 infection