Phylogenetic characterization of rabies virus isolates from Carnivora in Brazil

The incidence of canine rabies has been widely reported in Brazil, and new rabies virus (RV) variants, genetically similar to canine RV, have recently been isolated from foxes. In order to derive the epidemiological characteristics of Brazilian Carnivora RV, Brazilian RVs isolated from dogs, cats, and foxes were genetically analyzed. Brazilian Carnivora RV isolates were divided into 2 main lineages. The predominant lineage was found in dogs and cats, which included the Argentinean and Bolivian Carnivora RV isolates, and was extensively distributed throughout Brazil and surrounding countries. The other lineage consisted of three sublineages containing Brazilian dog and fox RV isolates, with the dog sublineages located on an internal branch of 2 fox sublineages, suggesting that RV transmission events might have occurred between foxes and dogs in the past. These results suggest that contact between dogs and wildlife has the potential to generate new rabies variants and that it is important to control RV infection cycles in both dogs and wildlife to prevent spread of rabies infection.     

Molecular epidemiological analysis of bat rabies viruses in Brazil

A molecular epidemiological analysis was performed in 19 rabies viruses (RVs) isolated from haematophagous, frugivorous and insectivorous bats, in Sao Paulo, Brazil. The authors carried out RT-PCR for amplification of the RV nucleoprotein (N) gene, and determined 1,335 nucleotide sequences of N gene by direct sequencing method. Phylogenetic analysis, which was based on the N gene of Brazilian RV isolates identified presently and previously, revealed that RVs isolated from bats were genetically divided into four lineages had a tendency to depend on the host bat species. The first lineage consisted mainly of haematophagous bat (Desmodus rotundus) isolates, including frugivorous bat (Artibeus spp.) isolates. Other three lineages consisted of insectivorous bat isolates; mainly Eptesicus spp., Molossus spp. and Nyctinomops spp. isolates, respectively. These results indicate a possibility of that there are bat species-specific RV variants in Brazil.     

Geographical distribution of vampire bat-related cattle rabies in Brazil

Seventy-seven rabies virus (RV) isolates originating from Brazilian cattle were genetically characterized. Partial nucleoprotein gene sequences of these isolates were phylogenetically and geographically analyzed. Cattle isolates, which clustered with the vampire bat-related RV group, were further subdivided into nine genetic subgroups. These subgroups were distributed widely in lowland regions, with some subgroups separated from each other by mountain ranges. In addition, separation of the groups in mountainous regions was correlated with altitude. These results indicate that cattle rabies is derived from several regionally-defined variants, which suggests that its geographical distribution is related to that of the vampire bat population.     

The evaluation of soybean meals from 3 major soybean-producing countries on productive performance and feeding value of pig diets

This study was conducted to evaluate 1) the effects of soybean meal (SBM) from 3 major SBM-producing countries (United States, Brazil, and India) on the growth performance, nutrient digestibility, and meat quality of growing-finishing pigs and 2) the feeding value of the evaluated SBM as a feedstuff for growing-finishing pigs. Soybean meal representative of each country was purchased on the open market. A total of 144 barrows with the average BW of 23.77 (SD = 1.52 kg) were allotted to 3 dietary treatments with 12 replicate pens per treatment and 4 pigs per pen. The US SBM used in this trial had greater CP and total AA contents, greater KOH protein solubility, and less crude fiber than SBM from either Brazil or India. Diets were formulated to be isolysinic and isocaloric. Pigs fed diets containing US SBM were heavier (P < 0.05) than pigs fed diets containing Brazilian or Indian SBM at 12 and 18 wk. Pigs fed diets containing US SBM had greater (P < 0.05) ADG and G:F throughout the overall period when compared with pigs fed SBM produced in Brazil or India. The DM and N digestibility were greater for US SBM (P < 0.05) than Brazilian and India SBM at 6, 12, and 18 wk. Pigs were slaughtered at the end of 18 wk, and no differences were observed on meat quality (backfat thickness, LM area, pH, meat color, water holding capacity, and drip loss) among the treatments, except lean percentages were less and backfat thickness was greater in pigs fed Brazilian and Indian SBM than US SBM. The cost per kilogram of BW gain of the experimental diet containing US SBM was less than that of diets containing Brazilian or Indian SBM, but it would depend on the relative prices of each SBM. Based on the results of the current experiment, the productivity and feeding value of US SBM seems to be greater than the SBM produced in Brazil and India.     

Genetic characterisation and analysis of infectious bronchitis virus isolated from Brazilian flocks between 2010 and 2015

1. Infectious bronchitis virus (IBV) variants in Brazil were isolated during 2010–2015 for epidemiological and molecular analysis to characterise the different variants and perform a bioinformatic analysis to compare with sequences of variants collected over the previous 40 years.

2. Of the 453 samples examined, 61.4% were positive for IBV and 75.9% of these were considered to have the BR-I genotype and were detected in birds of all ages distributed in all five Brazilian regions.

3. The ratio of non-synonymous substitutions per non-synonymous site (dN) to synonymous substitutions per synonymous site (dS), i.e. dN/dS, revealed a predominance of codons with non-synonymous substitutions in the first third of the S1 gene and a dN/dS ratio of 0.67. Additionally, prediction of N-glycosylation sites showed that most of the BR-I variants (from 2003 to early 2014) had an extra site at amino acid position 20, whereas the newest variants lacked this extra site.

4. These results suggest that Brazilian IBV variants probably underwent drastic mutations at various points between 1983 and 2003 and that the selection processes became silent after achieving a sufficiently effective antigenic structure for invasion and replication in their hosts. Brazilian IBV genotype BR-I is currently the predominant genotype circulating in Brazil and South America.     

Detection of porcine Circovirus type 2 (PCV2) variants PCV2-1 and PCV2-2 in Brazilian pig population

In the present study whole genome of six Brazilian isolates of PCV2 were sequenced, analyzed and compared with 35 other sequences (24 from other countries and 17 from Brazil). The phylogenetic analysis showed that mostly Brazilian variants of PCV2 were grouped as PCV2-1. Two isolates among the six analyzed here could not be grouped with any other PCV2-2 analyzed in this study. One of these isolates was from an aborted fetus with myocarditis and the other from a PMWS affected pig. The results pointed here showed that both groups of PCV2 are present in Brazilian pig population without any clear geographical correlation.     

Molecular characterization of unusual bovine group A rotavirus G8P[14] strains identified in western India: emergence of P[14] genotype

A total of 78 fecal specimens were collected from both apparently healthy (n=71) and diarrheic (n=7) cattle from an organized farm in Pune, western India in December 2007-January 2008. Three specimens tested positive for group A rotavirus (RV) by antigen capture ELISA were subjected to RT-PCR for amplification of entire coding regions of three structural (VP4, VP6 and VP7) and one nonstructural (NSP4) genes. All three strains were genotyped as G8P[14]. Phylogenetic analysis of the VP7 and VP4 genes showed clustering of the VP7 gene with G8 strains of bovine origin and VP4 gene with P[14] strains of human origin. The identification of VP6 and NSP4 genes to have I2 (subgroup I) and E2 (genotype A) specificity, respectively of bovine and human origin indicated independent segregation of genes in bovine RV strains. This study indicates circulation of a rare RV genotype, G8P[14] in western India. To our knowledge, this is the second report on RV G8[14] isolated from bovine species after bovine group A RV strain, SUN9 from Japan.     

Phylogenetic analysis of porcine rotavirus in Argentina: increasing diversity of G4 strains and evidence of interspecies transmission

Group A rotaviruses are one of the most frequently detected viral agents associated with neonatal diarrhea in piglets. In order to characterize rotavirus (RV) strains circulating in Argentinean swine, four porcine production farms located in Buenos Aires were studied. RV strains genotyped as P[6]G4, P[6]G8 and P[1]G6 were found in piglets under 30 days of age, without diarrhea. Phylogenetic and sequence analysis of the VP7 gene from G4 strains available in databases, reveals five porcine new lineages (III-VII) and three sublineages (VIIa-VIIc). The G4 porcine Argentinean strains were grouped with a porcine RV strain isolated in Brazil and another RV strain isolated from a child with diarrhea in Mexico, constituting an American lineage (VII). On the other hand, porcine G6 and G8 were closely related to RV's circulating in Argentinean cattle and South-American camelids, respectively. The fact that G4 porcine lineages were epidemiologically related to human strains, and G6 and G8 Argentinean porcine strains were found related to bovine and South-American camelids, respectively, suggests that pigs might play a crucial role as reservoir and generator of newly adapted emerging RV strains for human and other species.     

Genetic characterization of rabies viruses isolated from frugivorous bat (Artibeus spp.) in Brazil

In Latin America, rabies cases related to frugivorous bats have been reported since 1930's. Recently, two viruses isolated from Artibeus lituratus were proved to be vampire bat variants by monoclonal antibodies panels [2], but their genetic information is not well known. In this report, four rabies viruses were isolated from frugivorous bats (Artibeus spp.) in Brazil and their nucleoprotein gene sequences were determined. These isolates were found to be genotype 1 of lyssavirus and showed the maximum nucleotide sequence homology of 97.6-99.4% with vampire bat-related viruses in Brazil [6]. These results indicate that the Brazilian frugivorous bat rabies viruses in this study are closely related to vampire bat-related viruses that play a main role in rabies virus transmission to livestock in Brazil.     

Partial sequencing of env gene of bovine leukaemia virus from Brazilian samples and phylogenetic analysis

Analysis of the partial bovine leukaemia virus (BLV) env gp51 gene sequences obtained from three BLV strains isolated in three different regions of Brazil was carried out. The Brazilian BLV env gp51 sequences were compared with seven other corresponding sequences of BLV strains isolated in different countries and with consensus sequence as well. The obtained data point on qualitative and quantitative differences among the analysed strains as far as the occurrence of single point mutations is concerned. Two Brazilian strains show significantly higher mutation rate than other analysed strains. Amino acid analysis did not show, however, any substantial changes of the primary protein structure coded by well conserved region of BLV env gp51 gene. Based on the obtained data, the putative dendogram image of possible phylogenetic relations among the studied BLV strains is presented as well.     

Molecular changes associated with adaptation of equine influenza H3N8 virus in embryonated chicken eggs

Embryonated chicken eggs (ECEs) are routinely used to isolate equine influenza virus. Propagation of the virus in ECEs results in selection of variants. In the present study, we determined nucleotide sequences of entire coding regions of parent A/equine/Tottori/1/07 (H3N8) and its derivatives that have different passage histories in ECE. After 12 passages, nucleotide sequence analysis predicted 3 amino acid substitutions in hemagglutinin (HA; 2 in HA1 and 1 in HA2). The two amino acid substitutions in HA1 were located in the vicinity of the cell receptor-binding site. Three other amino acid substitutions were predicted in internal proteins, 1 in the M1, 1 in the NP and 1 in the PA. This is the first report showing mutations in the internal protein genes of equine influenza virus associated with adaptation to ECE.     

Phylogenetic relationships of Brazilian isolates of Pythium insidiosum based on ITS rDNA and cytochrome oxidase II gene sequences

Pythium insidiosum is an aquatic oomycete that is the causative agent of pythiosis. Advances in molecular methods have enabled increased accuracy in the diagnosis of pythiosis, and in studies of the phylogenetic relationships of this oomycete. To evaluate the phylogenetic relationships among isolates of P. insidiosum from different regions of Brazil, and also regarding to other American and Thai isolates, in this study a total of thirty isolates of P. insidiosum from different regions of Brazil was used and had their ITS1, 5.8S rRNA and ITS2 rDNA (ITS) region and the partial sequence of cytochrome oxidase II (COX II) gene sequenced and analyzed. The outgroup consisted of six isolates of other Pythium species and one of Lagenidium giganteum. Phylogenetic analyses of ITS and COX II genes were conducted, both individually and in combination, using four different methods: Maximum parsimony (MP); Neighbor-joining (NJ); Maximum likelihood (ML); and Bayesian analysis (BA). Our data supported P. insidiosum as monophyletic in relation to the other Pythium species, and COX II showed that P. insidiosum appears to be subdivided into three major polytomous groups, whose arrangement provides the Thai isolates as paraphyletic in relation to the Brazilian ones. The molecular analyses performed in this study suggest an evolutionary proximity among all American isolates, including the Brazilian and the Central and North America isolates, which were grouped together in a single entirely polytomous clade. The COX II network results presented signals of a recent expansion for the American isolates, probably originated from an Asian invasion source. Here, COX II showed higher levels bias, although it was the source of higher levels of phylogenetic information when compared to ITS. Nevertheless, the two markers chosen for this study proved to be entirely congruent, at least with respect to phylogenetic relationships between different isolates of P. insidiosum.     

Seroprevalence and molecular evidence for the presence of bovine immunodeficiency virus in Brazilian cattle

Data on the worldwide distribution of bovine immunodeficiency virus (BIV) and bovine leukemia virus (BLV) is limited. A prevalence study of antibodies to BIV and BLV was conducted in six different cattle herds in Brazil. Out of a total of 238 sera analyzed, 11.7% were found positive for anti-BIV p26 antibodies as determined by Western blot analysis, 2.1% were positive for anti-BLV gp51 antibodies as detected by immunodiffusion test. Peripheral blood mononuclear cells from BIV seropositive cattle were found to have BIV-provirus DNA, as detected by nested polymerase chain reaction. A nucleotide sequence corresponding to a 298 bp fragment of the BIV pol gene was also analyzed. Amino acid sequences of these Brazilian pol gene products showed 98.0 to 100% homology to the American strain BIV R29, 97.0 to 99.0% to Japanese BIV isolates, and divergence ranged from 0 to 4.0% among Brazilian BIV isolates. This evidence of the presence of BIV and BLV infections in Brazil should be considered a health risk to Brazilian cattle populations and a potential causative agent of chronic disease in cattle.     

Molecular characterization of canine coronavirus strains circulating in Brazil

To characterize canine coronavirus (CCoV) circulating in diarrheic puppies in Brazil, 250 fecal samples collected between 2006 and 2012 were tested. By using RT-PCR to partially amplify the M gene, CCoV RNA was detected in 30 samples. Sequence analysis of the M protein grouped eight strains with CCoV-I and another 19 with CCoV-II prototypes. To genotype/subtype the CCoV strains and assess the occurrence of single or multiple CCoV infections, RT-PCR of the S gene was performed, and 25/30 CCoV-positive strains amplified with one or two primer pairs. For 17/25 samples, single infections were detected as follows: six CCoV-I, nine CCoV-IIa and two CCoV-IIb. Eight samples were positive for more than one genotype/subtype as follows: seven CCoV-I/IIa and one CCoV-I/IIb. Sequence analysis revealed that the CCoV-I and IIa strains shared high genetic similarity to each other and to the prototypes. The Brazilian strains of CCoV-IIb displayed an aminoacid insertion that was also described in CCoV-IIb-UCD-1 and TGEV strains. Among the 25 CCoV-positive puppies, five had a fatal outcome, all but one of which were cases of mixed infection. The current study is the first reported molecular characterization of CCoV-I, IIa and IIb strains in Brazil.     

Molecular characterization of infectious bronchitis virus strains isolated from the enteric contents of Brazilian laying hens and broilers

Infectious bronchitis virus (IBV) is the causative agent of avian infectious bronchitis, which is characterized by respiratory, reproductive, and renal signs. However, the role of IBV as an enteric pathogen in still controversial. In Brazil, antigenic groups of IBV divergent from the Massachusetts serotype used for vaccination schedules in that country have already been demonstrated. The present study aimed to assess the different genotypes of IBV in Brazilian commercial poultry flocks by partial sequencing of the S1 amino-terminus coding region using enteric contents as samples and examine their relationship with the vaccine serotype currently in use. Samples of enteric contents were taken as pools of five birds from each of 18 poultry farms (17 broiler and one laying farm) from five Brazilian states between 2002 and 2006. Birds were presenting watery diarrhea and poor general condition but were without respiratory, renal, or reproductive signs. Conventional antibacterial and anticoccidial therapies were unsuccessful and, furthermore, all samples proved negative for rotavirus, reovirus, and astrovirus. Eleven IBV samples were isolated in embryonated eggs and resulted in S1 sequences. Phylogenetic analysis showed that these segregated into an exclusive cluster, close to serotype D274, but distant from Massachusetts. Mean amino acid identity amongst these Brazilian strains was 94.07%; amongst these and serotypes D274, 4/91, and Massachusetts, mean amino acid identity was 77.17%, 69.94%, and 68.93%, respectively. In conclusion, the presence of genotype variant strains of IBV in Brazilian poultry flocks has been demonstrated and might be the reason for the unsuccessful control of IBV in Brazil. Furthermore, these results also strengthen the implications of IBV in enteric diseases of poultry.     

Performance of three tropical hair sheep breeds.

The performance of three hair sheep breeds (Brazilian Somali, Morada Nova, and Santa Ines) was evaluated in the production environment of northeastern Brazil. Data from a total of 524 lambs sired by 21 rams and out of 190 ewes were analyzed. These data were collected from 1980 to 1983 at Sobral, Brazil from an experiment designed to compare performance of the three breeds. The traits included weights of lambs at birth, weaning, 8 mo, 10 mo, and yearling ages and ewe characters of weight at lambing (EWT), total lamb weight born (LWB), total lamb weight weaned (LWW), and prolificacy rate (PR). Differences (P < .01) among breeds were found for all characters. The Brazilian Somali, the smallest and slowest-gaining breed, was less sensitive to yearly variation than were the other breeds. The Santa Ines, the largest and fastest-gaining breed, was superior in LWB and LWW per ewe lambing. Averaged over the 4-yr period, the Morada Nova had the highest PR (1.82), and the Brazilian Somali and Santa Ines had similar PR (1.39 and 1.31, respectively). Environmental effects on PR due to yearly rainfall quantity and distribution pattern influenced lamb growth up to weaning and ewe reproduction performance. Breed x year (P < .05) interaction effects on PR were largely attributable to the Somali breed's exhibiting higher PR than the Santa Ines and Morada Nova breeds during the relatively wet years of 1981 and 1982.     

Mimosa tenuiflora as a cause of malformations in ruminants in the northeastern Brazilian semiarid rangelands

Craniofacial anomalies, eye malformations, and permanent flexures of the forelimbs are common malformations seen in ruminants grazing semiarid rangelands of Northeastern Brazil. To investigate the cause of these malformations, we fed 2 suspected plants, Mimosa tenuiflora or Prosopis juliflora, to groups of 4 pregnant goats each. Fresh green M. tenuiflora was collected daily and fed ad libitum to 4 goats in group 1 throughout pregnancy. This treatment group also received a supplemental feed concentrate equivalent to 1% body weight. Four goats in group 2 received a ration with 70% of P. juliflora pods and 30% hay throughout pregnancy. Four control goats were fed supplemental feed concentrate (1% body weight) and hay ad libitum throughout pregnancy. Goats treated with P. juliflora pods and the control goats delivered 9 normal kids. The four goats that were fed M. tenuiflora during pregnancy delivered 4 kids, 3 of which had abnormalities similar to those observed in field cases, including cleft lip, unilateral corneal opacity, ocular bilateral dermoids, buphthalmos with a cloudy brownish appearance of the anterior chamber due to an iridal cyst, and segmental stenosis of the colon. Malformations induced experimentally by M. tenuiflora were similar to those observed in field cases, suggesting that M. tenuiflora is a cause of the field cases observed in the Brazilian semiarid rangelands.