Candidate rotavirus vaccines have been prepared with reassortant strains specifically to protect against the 4 major rotavirus G serotypes (G1 -4). Many studies using P (VP4) genotyping methods have indicated that, worldwide, rotavirus strains of the 4 common G serotypes are each associated with 1 P genotype: GI, G3, and G4 are associated with P[8], and G2 is associated with P[4]. In contrast, G and P genotyping of rotavirus in specimens from India revealed that a high percentage of the childhood diarrhea strains belong to genotype P[6], and the most common strain had an unusual G serotype, G9. Similarly, in all regions surveyed in Brazil, apparent reassortants of genotype P[8], G5 were found in children with gastroenteritis. These studies indicate that while rotavirus strains have limited diversity in many settings, reassortment between common and uncommon serotypes or animal strains can arise in some settings and, thus, lead to unusual diversity.
We used reverse transcription-polymerase chain reaction (RT-PCR) to determine the P and G genotypes of 130 culture-adapted rotavirus strains isolated from 181 fecal specimens of children under 5 years of age from 9 states and the Federal District of Brazil. The 4 genotypes found most commonly worldwide were also common in Brazil and P[8]G1 was the most prevalent (43%), followed by P[4]G2 (12%), P[8]G3 (6%), and P[8]G4 (6%). However, unusual types P[8]G5, P[6]G2, P[9]G1, P[9]G3, and mixed infections were responsible for 12% and 21% of the cases, respectively. Genotype G5 strains were detected in specimens collected in all 9 areas surveyed from all 4 regions of Brazil. The unusual strain diversity in Brazil suggests that when tetravalent rotavirus vaccines currently being developed are introduced into Brazil, laboratory surveillance will be essential to monitor protection against unusual strains, particularly those of genotype 5, as well as emergence of novel reassortants that may evolve from the large pool of children with mixed infections.
The frequency of group A bovine rotavirus (gpA BRV) in calves from 1998 to 2002 was determined by the polyacrylamide gel electrophoresis technique in 2177 faecal samples, of which 1898 samples were diarrhoeic and 279 were of normal consistency (control group) that were collected from asymptomatic calves for comparative purposes. The animals were from beef and dairy cattle herds (n = 321) from 158 counties in seven States (Paraná, São Paulo, Minas Gerais, Mato Grosso do Sul, Mato Grosso, Goiás and Rondônia) and four Brazilian geographical regions (south, south-east, centre-west, and north). GpA BRV was detected in 19.4% (369/1898; p = 0.0001) of the samples collected in calves with diarrhoea and in only 2.2% (6/279; p = 0.0001) of the faeces with normal consistency. The proportion of positive samples collected from beef and dairy cattle herds was 22.8% (205/899; p = 0.0001) and 16.4% (169/999; p = 0.0005), respectively. In relation to age, a higher prevalence of infections was found in calves up to 30 days old, where 33.0% (189/573; p = 0.0001) and 20.2% (138/683; p = 0.0001) of the diarrhoeic faecal samples from beef and dairy cattle herds, respectively, were positive for gpA BRV. These results show the possible importance of inclusion of gpA BRV in the management of neonatal calf diarrhoea in Brazilian cattle herds.
Vesicular diseases are clinically and economically important infections that affect farm animals. North American studies have suggested that Senecavirus A infection might be associated with a vesicular disease in pigs known as porcine idiopathic vesicular disease (PIVD). In the beginning of 2015, outbreaks of porcine vesicular disease have occurred in six Brazilian states from three geographical regions. Official diagnostic tests were performed with negative results for classical vesicular diseases of compulsory reporting. This study investigated Senecavirus A infection in PIVD outbreaks in which other aetiological agents were ruled out. A primer set was designed to amplify a 542-bp product size of VP3/VP1 region of Senecavirus A genome in RT-PCR assay. Primer specificity was analysed in silico and in porcine biological specimens. For this, clinical specimens were collected from eight pig herds affected with PIVD, including vesicular fluid (n = 4) and swabs (n = 7) and scrapings of ruptured vesicles and ulcerative lesions (n = 5) from weaned and adult pigs. Clinically healthy animals (n = 52) of PIVD-affected and non-affected pig herds also were evaluated for Senecavirus A infection. The 16 samples from PIVD-affected animals were positive for Senecavirus A in the RT-PCR assay, while none of the clinically healthy pigs were detected with the virus. Sequencing analysis revealed high nucleotide (87.6-98.5%) and amino acid (95-99.4%) similarities to SVV-01 prototype and other Senecavirus A strains from North American pigs. Primer set presented herein was suitable for molecular characterization of Senecavirus A. The results suggest that Senecavirus A was the aetiological agent of the vesicular disease outbreaks in the evaluated pig herds. This is the first study to report the Senecavirus A infection in clinically affected pigs outside of North America. Senecavirus A was considered a novel emerging pathogen associated with an important vesicular disease in Brazil.
bEquine sarcoids are locally aggressive fibroblastic neoplasms considered to be the most common skin tumors of horses worldwide. Bovine papillomavirus types 1 and 2 have typically been associated with sarcoids in equids. Investigations aiming to identify papillomavirus strains, aside from bovine papillomaviruses 1 and 2, which might be associated with sarcoid lesions, have been lacking. The aim of this article is to report the identification of a third bovine papillomavirus type, bovine papillomavirus 13, associated with equine sarcoids. Six sarcoid lesions were collected from diverse anatomical sites on two horses from southern Brazil. To detect a broad spectrum of papillomavirus strains, eight degenerate primer pairs designed to detect conserved regions on the L1 and E1 genes were tested on the DNA samples. Direct sequencing was then performed on the obtained amplicons, and sequence identities were compared with sequences from all bovine papillomavirus types. The FAP59/FAP64, MY09/MY11, and AR-E1F2/AR-E1R4 sequences generated from the sarcoids were shown to present 99 to 100% identity with bovine papillomavirus 13, a new bovine papillomavirus type previously described in cattle. The results from this study suggest that there is a need to identify bovine papillomavirus type 13 and other papillomavirus strains that might be associated with sarcoids in diverse geographical areas; such investigations might establish the frequency of occurrence of this viral type in these common tumors of equids.
As amostras foram agrupadas em BVDV-1 (11/19), BVDV-2 (6/19) e num terceiro grupo de amostras denominadas "atípicas" (2/ 19). Das onze amostras genotipadas como BVDV-1, oito amostras foram sub-genotipadas como BVDV-1a, enquanto que a maioria (4/6) das amostras de BVDV-2 foi agrupada como BVDV2b. Duas amostras provenientes de fetos bovinos abortados foram classificadas como atípicas, não BVDV-1 e 2. A presença da diversidade genética de BVDV detectada nas amostras estudadas pode ser responsável por falhas vacinais e de diagnóstico e deve influenciar nas estratégias de controle do BVDV aplicadas nas diferentes regiões brasileiras.TERMOS DE INDEXAÇÃO: BVDV-1, BVDV-2, Pestivirus, Brazil, análise filogenética. INTRODUCTION INTRODUCTION INTRODUCTION INTRODUCTION INTRODUCTIONInfections of cattle by bovine viral diarrhea virus (BVDV) are widespread cause of major economic losses to the cattle industry (Houe 1999). Clinical symptoms may involve the reproductive, respiratory, immune, and gastrointestinal systems, with signs that may range from disease with high mortality rates to asymptomatic infections. The latter is observed in most cases (Pellerin et al. 1994, Ridpath et al.1994, Baker 1995, Fray et al. 2000.BVDV is an enveloped RNA virus that belongs to family Flaviviridae, genus Pestivirus. The viral positive single stranded genome of approximately 12.5 kb in size contains a single open reading frame (ORF) flanked by two non-translating terminal regions, named 5' and 3'-UTR. The single ORF is directly translated and gives rise to a long polyprotein which is co-translationally cleaved, originating 10 to 12 mature viral proteins (Collet et al. 1988, Meyer et al. 1989.Isolates have been subdivided in genotypes BVDV-1 and BVDV-2. These were further split into subgenotypes.
Antimicrobials are sometimes given to food animals at low doses in order to promote faster growth. However, the mechanisms by which those drugs improve performance are not fully understood. This study aimed to investigate the impact of zinc bacitracin (55g/ton), enramycin (10g/ton); halquinol® (30g/ton); virginiamycin (16,5g/ton) and avilamycin (10g/ton) on the cecal microbiota of broiler chicken, compared to a control group. Six hundred and twenty four chicks (Cobb 500) arriving to an experimental unit were randomly assigned into each treatment with four repetitions per treatment. The cecal content of 16 animals per treatment (n = 96) was used for DNA extraction and sequencing of the V4 region of the 16S rRNA gene using Illumina technology. The use of antimicrobials induced significant changes in membership but not in structure of the cecal microbiota compared to the control group, suggesting a greater impact on the less abundant species of bacteria present in that environment. Halquinol was the only drug that did not affect microbial membership. Firmicutes comprised the major bacterial phylum present in the cecum of all groups. There was no statistical difference in relative abundances of the main phyla between treated animals and the control group (all P>0.05). Treatment with enramycin was associated with decreased richness and with lower relative abundance of unclassified Firmicutes, Clostridium XI, unclassified Peptostreptococcaceae (all P<0.001) and greater abundance of Clostridium XIVb (P = 0.004) and Anaerosporobacter spp. (P = 0.015), and treatment with bacitracin with greater relative abundance of Bilophila spp. (P = 0.004). Several bacterial genera were identified as representative of usage of each drug. This study used high throughput sequencing to characterize the impact of several antimicrobials in broiler chicken under controlled conditions and add new insights to the current knowledge on how AGPs affect the cecal microbiota of chicken.
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