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The aim with this study was to use interdisciplinary techniques and visions in order to identify the modulating effect of tannins on adaptive factors in lactating goats with different genetic patterns, through the assessment of digestibility and nutrient intake, ingestive behavior and rumen metagenome. We used in this study 8 of the Repartida ecotype and 6 of the Canindé breed goats, on average five years old, distributed in a completely randomized design, in a 2 × 2 factorial design, with two genetic groups and two diets. The applied diets were: basal diet and inclusion of 5% commercial tannin extract in basal diet. Intake and apparent digestibility of nutrients were evaluated, based on the quantification of the offered feed and refusals, and bromatological evaluation of samples of the offered feed, refusals and feces. Behavioral data were collected in 24-h continuous visual observations. The ruminal fluid was collected and DNA extraction, sequencing, and evaluation of relative abundance of the rumen microbiome were performed. The data obtained were analyzed statistically, through analysis of variance with 5% significance and, when necessary, a comparison of means test was applied. In this preliminary findings was observed that the genetic group factor caused changes in the number of chews and the relative abundance of microorganisms (P = 0.0290 and P = 0.0051). The diet factor influenced digestibility, which better values were observed for the tannin diet (P = 0.0049), in addition, it promoted changes in the rumen microbiota, with a beneficial modulatory characteristic. The inclusion of 5% tannin extract from Acacia mearnsii modulates the rumen microbiome, improving the apparent digestibility of nutrients without affecting the feed intake of goats from the Repartida and Canindé genetic groups.

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.

Dermatosparaxis, also known as Ehlers-Danlos syndrome, is a recessive genetic disorder characterized by defects in collagen production, leading to skin fragility and delayed wound healing. In sheep this disease is associated to a transversion c.421G > T located on exon 2 of the gene ADAMTS2 and presents a special importance for the White Dorper breed. This study aims to identify carriers for the mutation associated with dermatosparaxis in Brazilian White Dorper herds and also to better understand the origin and the possibility of dissemination of this disease combining molecular and genealogical approaches. Genotyping by PCR-RFLP revealed the presence of seven out 66 heterozygotes, resulting in an estimated frequency of 5.3% for the dermatosparaxis associated allele in Brazilian White Dorper sheep. Pedigree analysis permitted the identification of two separate groups of individuals carrying the dermatosparaxis associated allele, one represented by descendants from individuals imported from South Africa and the second originated from animals imported from Australia. These findings suggest that the implementation of a program aiming to eradicate/control of dermatosparaxis in Brazilian White Dorper sheep is needed and the success of this strategy initially depends on the utilization of a molecular testing to detect carriers.

RESUMO: O gene floR descrito é descrito pela literatura como o responsável pela resistência ao florfenicol, que é um antimicrobiano amplamente utilizado na aquicultura. Esse gene já foi relatado em muitas espécies de bactérias, inclusive no gênero Aeromonas. Essas bactérias causam alta mortalidade na piscicultura trazendo prejuízos econômicos. É importante que haja estudos sobre esse gene e possíveis mutações que possam levar a alterações na estrutura e função da proteína. Os objetivos desse estudo foram caracterizar o gene floR em isolados de Aeromonas spp. obtidas do Vale do São Francisco e verificar se a presença desse gene está associada com a resistência ao florfenicol. Foram realizadas reações em cadeia da polimerase (PCR) para a presença do gene floR em 27 isolados de Aeromonas spp.. Amostras positivas para a presença do gene foram sequenciadas e analisadas quanto à presença de polimorfismos por meio de alinhamentos. Os diferentes haplótipos detectados foram utilizados para análises com os programas SIFT e PolyPhen para predição de alteração de função proteica. A modelagem estrutural da proteina codificada pelo gene floR foi realizada com o programa Modeller e, os modelos foram avaliados pelo Procheck, Verify3D e Whatif. A similaridade da estrutura tridimensional da proteína referência com as estruturas tridimensionais das proteínas codificadas pelos diferentes haplótipos foi comparada através do TM-align. A resistência das bactérias ao florfenicol foi avaliada através do teste de microdiluição em caldo, o qual também foi realizado na presença do carbonil cianeto m-clorofenil hidrazona para verificar o efeito da inibição da bomba de efluxo sobre tal resistência. Dos vinte e sete isolados avaliados quanto a presença do gene floR, 14 isolados foram positivos e 10 foram sequenciados, o que permitiu a identificação de três polimorfismos no gene floR, que levaram a construção de três haplótipos diferentes (TAA, TTA e CTG). As análises realizadas com os programas SIFT e PolyPhen apontaram que os haplótipos TTA e TAA provavelmente poderiam alterar a estrutura e função da proteína. As proteínas modeladas para os três haplótipos demonstraram possuir praticamente a mesma conformação estrutural entre si. Todos os isolados que apresentaram o gene foram resistentes ao florfenicol e aqueles que não apresentavam foram sensíveis. O teste na presença do Carbonil Cianeto m-Clorofenil Hidrazona foi realizado para três isolados, cada isolado representando um haplótipo, sendo possível observar a inibição do crescimento bacteriano em todas as concentrações independente do haplótipo. Os resultados obtidos nesse estudo mostram que a resistência ao flofenicol em Aeromonas spp. pode ser explicada pela presença do gene floR, e que esse gene está relacionado com uma bomba de efluxo. As mutações verificadas no gene floR, parecem não estar envolvidas com alteração de estrutura e função da proteína codificada por esse gene. ABSTRACT: The floR gene is described in related literature as responsible for resistance to florfenicol, which is a widely used antimicrobial agent in aquaculture. This gene has been reported in many species of bacteria, including the genus Aeromonas. These bacteria cause high mortality in fish farming bringing economic losses. It is important that studies of this gene and possible mutations that can lead to changes in the structure and function of the protein. The aim of this study was to characterize the floR gene in isolates of Aeromonas spp. and check if the presence of this gene is associated with resistance to florfenicol in Aeromonas spp. obtained from the San Francisco Valley. PCR (Polymerase Chain Reaction) were also performed to verify the presence of the floR gene in 27 isolates of Aeromonas spp. Positive samples for the presence of the gene were sequenced and analyzed for the presence of polymorphisms using alignments. Different haplotypes detected were used for analysis with the SIFT and PolyPhen programs for prediction of changes in protein function. The structural modeling of protein encoded by the floR gene was performed using the Modeller software, and the models were evaluated by Procheck, Verify3D and Whatif. The similarity of the dimensional structure of reference protein with the dimensional structures of the proteins encoded by the different haplotypes was compared by TM-align. Bacterial resistance to florfenicol was assessed by the microdilution test, which was also performed in the presence of carbonyl cyanide m-chlorophenyl hydrazone to verify the effect of inhibiting the efflux pump. 14 isolates were positive for the presence of floR gene and 10 were sequenced and allowed the identification of three polymorphisms in the floR gene, which led to construction of three different haplotypes (TAA TTA and CTG). The analyzes carried out with the SIFT and PolyPhen programs showed that the TTA and TAA haplotypes could probably change the protein structure-function. Proteins modeled for the three haplotypes were found to have substantially the same structural conformation with each other. All isolates presenting the gene were resistant to florfenicol and those who did not have were sensitive. The test in the presence of carbonyl cyanide m-chlorophenylhydrazone was conducted for three isolates, representing each single haplotype and was observed inhibition of bacterial growth at all concentrations independent of the haplotype. The results of this study show that resistance to flofenicol in Aeromonas spp. may be explained by the presence of floR gene and that this gene is associated with an efflux pump. Mutations observed in floR gene do not appear to be involved with chenges in structure and function of the protein encoded by gene.

The Ovis aries species is phenotypically diverse and it is bred around the world for meat, milk and wool production. In the 1980s, small farmers in the semi-arid region of Pernambuco, Brazil, initiated the introgression of genes from Santa Inês and Bergamácia breeds in their local sheep of undefined breed, and the selection of individuals in an unstructured form, giving rise to an ecotype with unique characteristics called Berganês. The aim of this study was to perform genetic structure analysis of the Berganês ecotype population on farms in the state of Pernambuco using the Illumina® BeadChip OvineSNP50 high density chip as a way of increasing knowledge about the ecotype. Animals from seven farms were genotyped, totaling 96 animals (17 males and 79 females). Of the 54,241 Single Nucleotide Polymorphism (SNPs) found, we elected the ones with GenCall Score > 0.5, Hardy-Weinberg equilibrium (significance at 0.01) and lower allele frequency (MAF) > 0.2. In addition, only SNPs located on the autosomal chromosomes were maintained, according to version 4.0 of the sheep genome, with 39,250 SNPs being selected. The observed and expected mean heterozygosity values were, respectively, 0.37159 and 0.37943. The F statistics found were: FIS = 0.02622, FST = 0 and FIT = 0.02394. Most of the variability found (97.61%), which was estimated by AMOVA, is uniformly distributed within the herds and the Principal Component Analysis (PCA) did not allow the visual identification of a substructure considering herds, sex or phenotypic characteristics (coat color, ear size and insertion, and head morphology). Thus, the genetic variability presented in the animals of the Berganês ecotype is distributed homogeneously among the herds analyzed. Therefore, the genetic characterization presented here represents a key point in the creation of conservation plans and breeding programs, improving the efficiency of selection processes and the selection of breeders.

Neospora caninum is an obligate intracellular tissue cyst-forming coccidian parasite and it was first described in dogs. Despite the relevance of wild canids in the transmission chain of N. caninum, there are few studies in Brazil. The aim of the present study was to detect N. caninum DNA in feces of free-range and captive crab-eating fox (Cerdocyon thous) from different states of northeastern Brazil. Fecal samples of eighteen crab-eating foxes (fifteen individually and three pools) were collected in sterile containers and were kept cool at −20 °C until further processing. All fecal samples were subjected to DNA extraction. A nested PCR targeting the ITS-1 gene was performed for N. caninum. All the positive bands were extracted from the gel and purified. Forward and reverse strands were sequenced and the nucleotide sequences obtained were compared with N. caninum sequences deposited in Genbank. The alignment was edited and phylogenetic reconstruction was based on the ITS1 gene sequences. Thirteen stool samples were PCR-positive for N. caninum DNA. Nine out of thirteen positive samples showed similarity between 99%–100% for N. caninum in relation to the sequence U25044.1 stored at GenBank. The crab-eating fox could have an important role in the sylvatic cycle of Neospora caninum in Brazil. Experimental infections studies involving these wild canids may confirm if the crab-eating foxes are definitive hosts of N. caninum.