Molecular screening for the mutation associated with canine degenerative myelopathy (SOD1:c.118G > A) in German Shepherd dogs in Brazil.

Canine Degenerative Myelopathy is a late onset recessive autosomal disease characterized by a progressive ascending degeneration of the spinal cord. Two causal mutations are associated with this disease: a transition (c.118G>A) in exon 2 of the SOD1 that was described in several breeds and a transversion (c.52A>T) in exon 1 of the same gene described in Bernese Mountain dogs. The aim of this study was to understand the impact of the SOD1:c.118G > A mutation by genotyping a population of German Shepherd dogs in Brazil. A PCR-RFLP approach was used to genotype 97 healthy individuals belonging from the Northeast (Bahia and Pernambuco states) and South (Santa Catarina state) regions of Brazil. A total of 95 individuals were successfully genotyped resulting in an observed genotype frequency (with 95% confidence interval) of: 0.758 (0.672-0.844), 0.242 (0.156-0.328) and 0.000 (0.000-0.000) for "GG", "AG" and "AA" genotypes, respectively. To our knowledge, this is the first attempt to describe the presence of the "A" allele associated with CDM (SOD1:c.118G > A) in German Shepherd dogs in Brazil and, as such, these results contribute toward important epidemiological data in this country and to the knowledge of the distribution of the aforementioned mutation worldwide

Identification of selection signatures in livestock species

The identification of regions that have undergone selection is one of the principal goals of theoretical and applied evolutionary genetics. Such studies can also provide information about the evolutionary processes involved in shaping genomes, as well as physical and functional information about genes/genomic regions. Domestication followed by breed formation and selection schemes has allowed the formation of very diverse livestock breeds adapted to a wide variety of environments and with special characteristics. The advances in genomics in the last five years have enabled the development of several methods to detect selection signatures and have resulted in the publication of a considerable number of studies involving livestock species. The aims of this review are to describe the principal effects of natural/artificial selection on livestock genomes, to present the main methods used to detect selection signatures and to discuss some recent results in this area. This review should be useful also to research scientists working with wild animals/non-domesticated species and plant biologists working with breeding and evolutionary biology

The presence of plasmids in Aeromonas hydrophila and its relationship with antimicrobial and heavy metal-resistance profiles

ABSTRACT: Aeromonas hydrophila is a common fish pathogen that causes extensive damage to aquaculture. To develop and implement a more adequate strategy to farm fish, it is crucial to understand the bacterial-resistance levels and their transference dynamics. The objective of this study was to analyze the resistance profile of isolated Aeromonas hydrophila to antimicrobial agents and heavy metals and draw a correlation of the observed profiles with the presence of plasmids. Resistance of the isolated bacteria to antimicrobial agents (oxacilin, gentamicin, tetracycline, and nalidixic acid) and heavy metals (cadmium, lead, copper, and manganese) was verified using the minimum bactericidal concentration (MBC) and minimum inhibitory concentration (MIC) standards. The Multiple Antibiotic Resistance Index (MAR Index) was calculated. Plasmids were extracted by using a common methodology described elsewhere. Mann-Whitney Test, implemented in the R environment, was used to determine the correlation between resistance and plasmids presence. A high resistance to almost all antimicrobial agents and heavy metals was observed, except to gentamicin and cadmium. The MAR index results showed resistance to all antimicrobial profiles. Of the isolated bacteria, 14 showed the presence of plasmids. However, no correlation was noted between the resistance profile and the plasmid presence for these isolates, indicating that the genes responsible for resistance to microbial agents and heavy metals are present in the cromossomic DNA, which in turn suggested the possibility of gene transfer between the isolated bacteria. The resistance to heavy metals can be linked to heavy utilization of fertilizers along the Sao Francisco River

Association of CSSM066 and ILSTS011 microsatellite markers and thyroglobulin gene SNP with backfat in Canchim cattle

Canchim, a synthetic breed of cattle derived from the Charolais and Zebu group has been used in the beef-cattle industry in Brazil as an alternative for intensifying production. One of the main concerns with this breed is its poor fat deposition and consequently, there is an effort to increase the performance for this trait. The thyroglobulin gene is located in a QTL region for fat deposition, and reports describe the influence of a polymorphism in the 5´ leader sequence of that gene on marbling and subcutaneous fat thickness. This study analyzed the association of this polymorphism in the thyroglobulin gene, as well as of two flanking microsatellite markers, CSSM066 and ILSTS011, with backfat thickness in 987 Canchim beef cattle. The CSSM066 and ILSTS011 microsatellite markers have a effect on fat thickness in the studied populations. However, this trait did not have association with the polymorphism of the thyroglobulin gene, which suggests that other genes of bovine chromosome 14 may be responsible for the variation in this trait.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Bactérias isoladas de abscessos em pequenos ruminantes inspecionados na região semiárida do Brasil

Loss in the supply chain of small ruminants owing to condemnations of carcasses in the abattoirs and slaughterhouses is common in northeastern Brazil. This study aims to identify bacterial agents, including Mycobacterium spp., in the abscesses found in the postmortem analysis of the carcasses of sheep and goats bred in northeastern Brazil. Our analysis involved 679 goats and 1,838 sheep carcasses. Abscess samples were extracted and inoculated on blood agar and Lowenstein Jensen with pyruvate or glycerol for bacterial isolation. We then performed polymerase chain reaction of the hps 65 gene; samples positive for Mycobacterium spp. were subjected to DNA sequencing. Relative frequencies of abscesses in goats and sheep were 5.44 and 3.26%, respectively. Microbiological analysis revealed 87.7% bacterial growth in the inoculated samples. Among these, Corynebacterium pseudotuberculosis represented 67.7% of the isolates. We observed 1.9% mycobacteria growth in the abscess samples inoculated on Lowenstein-Jensen medium. PCR of DNA extracted from abscesses samples showed amplification of 0.9% of samples. After sequencing, Mycobacterium spp. isolate was identified as M. novocastrense. C. pseudotuberculosis was the main agent responsible for the formation of abscesses in the examined animals, and we did not identify any species of the M. tuberculosis complex in the examined small ruminants.Perdas na cadeia produtiva dos pequenos ruminantes pela condenação de carcaças e vísceras são comuns nos matadouros/frigoríficos da região nordeste do Brasil. Este estudo objetivou identificar agentes bacterianos, inclusive Mycobacterium spp., no conteúdo de abscessos encontrados no exame post mortem de caprinos e ovinos criados em regiões do nordeste do Brasil. Foram inspecionados no exame post mortem 679 caprinos e 1.838 ovinos. Para o isolamento bacteriano as amostras foram cultivadas em meio Agar Sangue e Lowenstein Jensen contendo piruvato ou glicerol. Além do cultivo, foi realizada identificação molecular para Mycobacterium spp. pela técnica de Reação em Cadeia de Polimerase (PCR) em que foram utilizados primers que amplificam fragmentos de parte do gene hsp65. As amostras positivas para micobactérias foram submetidas ao sequenciamento de DNA. As frequências relativas de abscessos em caprinos e ovinos foram de 5,44% (37/679) e 3,26% (60/1.838), respectivamente. No exame microbiológico, utilizando o meio Ágar Sague, observou-se crescimento bacteriano em 87,7% (93/106) das amostras cultivadas. Destes, o Corynebacterium pseudotuberculosis representou 67,7% (63/93) dos isolados. Do cultivo em meio Lowenstein Jensen foram isolados micobactérias em 1,9% (2/106) das amostras de abscessos e, na PCR com DNA extraído direto das amostras de abscessos, observou-se amplificação em 0,9% (1/106) das amostras. No sequenciamento o isolado de Mycobacterium spp. foi confirmado como M. Novocastrense. C. pseudotuberculosis foi o principal agente responsável pela formação de abscessos nos animais avaliados e não foi identificada nenhuma espécie do complexo M. tuberculosis nos pequenos ruminantes inspecionados

Association of CSSM066 and ILSTS011 microsatellite markers and thyroglobulin gene SNP with backfat in Canchim cattle

Canchim, a synthetic breed of cattle derived from the Charolais and Zebu group has been used in the beef-cattle industry in Brazil as an alternative for intensifying production. One of the main concerns with this breed is its poor fat deposition and consequently, there is an effort to increase the performance for this trait. The thyroglobulin gene is located in a QTL region for fat deposition, and reports describe the influence of a polymorphism in the 5´ leader sequence of that gene on marbling and subcutaneous fat thickness. This study analyzed the association of this polymorphism in the thyroglobulin gene, as well as of two flanking microsatellite markers, CSSM066 and ILSTS011, with backfat thickness in 987 Canchim beef cattle. The CSSM066 and ILSTS011 microsatellite markers have a effect on fat thickness in the studied populations. However, this trait did not have association with the polymorphism of the thyroglobulin gene, which suggests that other genes of bovine chromosome 14 may be responsible for the variation in this trait

Comprehensive Analyses of Bone and Cartilage Transcriptomes Evince Ion Transport, Inflammation and Cartilage Development-Related Genes Involved in Chickens’ Femoral Head Separation

Femoral head separation (FHS) is usually a subclinical condition characterized by the detachment of articular cartilage from the bone. In this study, a comprehensive analysis identifying shared and exclusive expression profiles, biological processes (BP) and variants related to FHS in the femoral articular cartilage and growth plate in chickens was performed through RNA sequencing analysis. Thirty-six differentially expressed (DE) genes were shared between femoral articular cartilage (AC) and growth plate (GP) tissues. Out of those, 23 genes were enriched in BP related to ion transport, translation factors and immune response. Seventy genes were DE exclusively in the AC and 288 in the GP. Among the BP of AC, the response against bacteria can be highlighted, and for the GP tissue, the processes related to chondrocyte differentiation and cartilage development stand out. When the chicken DE genes were compared to other datasets, eight genes (SLC4A1, RHAG, ANK1, MKNK2, SPTB, ADA, C7 and EPB420) were shared between chickens and humans. Furthermore, 89 variants, including missense in the SPATS2L, PRKAB1 and TRIM25 genes, were identified between groups. Therefore, those genes should be more explored to validate them as candidates to FHS/FHN in chickens and humans

Genomic Characterization of <i>Aeromonas veronii</i> Provides Insights into Taxonomic Assignment and Reveals Widespread Virulence and Resistance Genes throughout the World

Aeromonas veronii is a Gram-negative bacterial species that causes disease in fish and is nowadays increasingly recurrent in enteric infections of humans. This study was performed to characterize newly sequenced isolates by comparing them with complete genomes deposited at the NCBI (National Center for Biotechnology Information). Nine isolates from fish, environments, and humans from the São Francisco Valley (Petrolina, Pernambuco, Brazil) were sequenced and compared with complete genomes available in public databases to gain insight into taxonomic assignment and to better understand virulence and resistance profiles of this species within the One Health context. One local genome and four NCBI genomes were misidentified as A. veronii. A total of 239 virulence genes were identified in the local genomes, with most encoding adhesion, motility, and secretion systems. In total, 60 genes involved with resistance to 22 classes of antibiotics were identified in the genomes, including mcr-7 and cphA. The results suggest that the use of methods such as ANI is essential to avoid misclassification of the genomes. The virulence content of A. veronii from local isolates is similar to those complete genomes deposited at the NCBI. Genes encoding colistin resistance are widespread in the species, requiring greater attention for surveillance systems