Protein expression and genetic variability of canine Can f 1 in golden and Labrador retriever service dogs.

BackgroundValued for trainability in diverse tasks, dogs are the primary service animal used to assist individuals with disabilities. Despite their utility, many people in need of service dogs are sensitive to the primary dog allergen, Can f 1, encoded by the Lipocalin 1 gene (LCN1). Several organizations specifically breed service dogs to meet special needs and would like to reduce allergenic potential if possible. In this study, we evaluated the expression of Can f 1 protein and the inherent variability of LCN1 in two breeds used extensively as service dogs. Saliva samples from equal numbers of male and female Labrador retrievers (n = 12), golden retrievers (n = 12), and Labrador-golden crosses (n = 12) were collected 1 h after the morning meal. Can f 1 protein concentrations in the saliva were measured by ELISA, and the LCN1 5' and 3' UTRs and exons sequenced.ResultsThere was no sex effect (p > 0.2) nor time-of-day effect; however, Can f 1 protein levels varied by breed with Labrador retrievers being lower than golden retrievers (3.18 ± 0.51 and 5.35 ± 0.52 μg/ml, respectively, p < 0.0075), and the Labrador-golden crosses having intermediate levels (3.77 ± 0.48 μg/ml). Although several novel SNPs were identified in LCN1, there were no significant breed-specific sequence differences in the gene and no association of LCN1 genotypes with Can f 1 expression.ConclusionsAs service dogs, Labrador retrievers likely have lower allergenic potential and, though there were no DNA sequence differences identified, classical genetic selection on the estimated breeding values associated with salivary Can f 1 expression may further reduce that potential

Soroprevalência da infecção por Toxoplasma gondii (Nicole & Manceaux, 1909) e a infecção por retrovírus em população urbana de gatos domésticos (Felis catus, Linnaeus, 1758) no Rio de Janeiro, Brazil

Cats, as definitive host, play an important role in the transmission of Toxoplasma gondii. This study aimed to establish the seroprevalence of anti-T. gondii immunoglobulins G and M, and determine the frequency of oocysts in the feces of the domestic cat population in Rio de Janeiro, Brazil. We also aimed to study the association between T. gondii infection and age, sex, breed, lifestyle, diet and retroviral infection. A total of 108 cats were included in the study and fecal samples of 54 of those cats were obtained. Only 5.6% of the cats were seropositive for anti-T. gondii immunoglobulins using the indirect hemagglutination test. None of the 54 cats presented oocysts in their fecal samples. Although not statistically significant, males, mixed-breed, free-roaming and cats aged two years and older were found to be more exposed. Age, lifestyle and the use of litter boxes were found to play an important role as risk factors. Anemia and retroviral infections were independent of T. gondii infection. No antibodies were detected in the majority of cats (94.4%), indicating that those cats had never been exposed to the parasite and, therefore, once infected, they could present the risk of shedding large numbers of oocysts into the environment.Os gatos, como hospedeiros definitivos, apresentam um papel fundamental na transmissão do Toxoplasma gondii. Nosso estudo teve como objetivo determinar a presença de imunoglobulinas G e M anti-T. gondii, e a frequência de oocistos nas fezes de uma população de gatos domésticos do Rio de Janeiro, Brasil. Objetivou-se ainda estudar a associação da infecção por T. gondii com a idade, sexo, raça, estilo de vida, dieta e infecção por retrovírus. Um total de 108 gatos foi incluído no estudo e 54 amostras de fezes foram obtidas desses animais. Somente 5,6% dos gatos foram sororreagentes para T. gondii, utilizando-se o teste de hemaglutinação indireta. Nenhum dos 54 gatos apresentou oocistos em suas amostras fecais. Embora sem comprovação estatística, machos, sem raça definida, com acesso livre às ruas e gatos com mais de dois anos de idade tenderam a ser mais expostos ao parasito. Idade, estilo de vida e uso de caixa de areia foram considerados importantes fatores de risco. Anemia e infecção por retrovírus não apresentaram relação com infecção por T. gondii. Não foram detectados anticorpos na maioria dos gatos (94,4%), indicando que esses gatos nunca foram expostos ao parasito e que, se infectados, poderão eliminar grande número de oocistos no ambiente

Novel Locus Associated with Symmetrical Lupoid Onychodystrophy in the Bearded Collie

Symmetrical lupoid onychodystrophy (SLO) is characterized by inflammation of the nail bed and nail sloughing that causes affected dogs considerable pain. Disease etiology remains unclear, although an autoimmune component is suspected. A genome-wide association study on Bearded Collies revealed regions of association on canine chromosomes (CFA) 12 and 17. The large region of association on CFA12 likely consists of two smaller linked regions, both of which are also linked to the dog leukocyte antigen (DLA) class II genes. Dogs homozygous for the alternate allele at the top CFA12 SNP also carried two DLA class II risk haplotypes for SLO, and this locus explained most of the increased risk for disease seen throughout the CFA12 region of association. A stronger peak was seen on CFA17 when analysis was done solely on dogs that carried DLA class II risk haplotypes for SLO. The majority of SLO dogs carried a homozygous alternate genotype on CFA12 and at least one CFA17 risk haplotype. Our findings offer progress toward uncovering the genetic basis of SLO. While the contribution of the CFA17 region remains unclear, both CFA12 and CFA17 regions are significantly associated with SLO disease expression in the Bearded Collie and contain potential candidate genes for this disease.Peer reviewe

Correction to: Genetic characterization of Addison’s disease in Bearded Collies

An amendment to this paper has been published and can be accessed via the original article

Correction to: Genetic characterization of Addison’s disease in Bearded Collies

An amendment to this paper has been published and can be accessed via the original article

Correction to: Genetic characterization of Addison’s disease in Bearded Collies

An amendment to this paper has been published and can be accessed via the original article

Individual signatures and environmental factors shape skin microbiota in healthy dogs

The individual, together with its environment, has been reported as the main force driving composition and structure of skin microbiota in healthy dogs. Therefore, one of the major concerns when analyzing canine skin microbiota is the likely influence of the environment. Despite the dense fur covering, certain skin diseases exhibit differential prevalence among skin sites, dog breeds, and individuals. We have characterized the normal variability of dog skin microbiota in a well-controlled cohort of a large number of Golden-Labrador Retriever crossed dogs (N = 35) with similar ages, related genetic background, and a shared environment. We found that the individual drives the skin microbiota composition and structure followed by the skin site. The main bacterial classes inhabiting dog skin in this cohort are Gammaproteobacteria and Bacilli. We also detected bacteria associated to the environment on different dog skin sites that could be reflecting the different degrees of exposure of each skin site and each dog. Network analyses elucidated bacterial interactions within and between skin sites, especially in the chin, abdomen, axilla, and perianal region, with the highly shared interactions probably representing an anatomical, behavioral, or environmental component. When analyzing each skin site independently to assess host-specific factors, we found that temporality (season of birth and time spent in the kennel) affected all the skin sites and specially the inner pinna. The most abundant taxon driving this difference was Sphingomonas. We also found taxonomic differences among male and female dogs on the abdomen, axilla, and back. We observed a large inter-individual variability and differences among skin sites. Host-specific variables, such as temporality or sex, were also shaping skin microbiota of healthy dogs, even in an environmental homogenous cohort. The online version of this article (10.1186/s40168-017-0355-6) contains supplementary material, which is available to authorized users

Whole Genome Sequencing Reveals Multiple Linked Genetic Variants on Canine Chromosome 12 Associated with Risk for Symmetrical Lupoid Onychodystrophy (SLO) in the Bearded Collie

In dogs, symmetrical lupoid onychodystrophy (SLO) results in nail loss and an abnormal regrowth of the claws. In Bearded Collies, an autoimmune nature has been suggested because certain dog leukocyte antigen (DLA) class II haplotypes are associated with the condition. A genome-wide association study of the Bearded Collie revealed two regions of association that conferred risk for disease: one on canine chromosome (CFA) 12 that encompasses the DLA genes, and one on CFA17. Case-control association was employed on whole genome sequencing data to uncover putative causative variants in SLO within the CFA12 and CFA17 associated regions. Genotype imputation was then employed to refine variants of interest. Although no SLO-associated protein-coding variants were identified on CFA17, multiple variants, many with predicted damaging effects, were identified within potential candidate genes on CFA12. Furthermore, many potentially damaging alleles were fully correlated with the presence of DLA class II risk haplotypes for SLO, suggesting that the variants may reflect DLA class II haplotype association with disease or vice versa. Strong linkage disequilibrium in the region precluded the ability to isolate and assess the individual or combined effect of variants on disease development. Nonetheless, all were predictive of risk for SLO and, with judicious assessment, their application in selective breeding may prove useful to reduce the incidence of SLO in the breed