Cyathostomine egg reappearance period following ivermectin treatment in a cohort of UK Thoroughbreds.

Background: In spite of the emergence of populations of drug-resistant cyathostomins worldwide, little is known of parasite species responsible for 'early egg shedding' in cohorts of horses subjected to treatment with widely used anthelmintics (e.g. ivermectin [IVM]). In this study, we determined the cyathostomin egg reappearance period (ERP) after IVM treatment of a cohort of yearlings from a large Thoroughbred (TB) stud farm in the United Kingdom, and identified species of IVM-'resistant' cyathostomins using a combination of fundamental parasitology techniques coupled with advanced molecular tools. Methods: Individual faecal samples were collected from TB yearlings with cyathostomin infection prior to IVM treatment, as well as at 2, 14, 21, 28, 35, 42 and 49 days posttreatment. Faecal egg counts (FEC) were performed for each individual sample for determination of ERPs. In addition, individual larval cultures were performed and representative numbers of third stage larvae (L3s) harvested from each culture were subjected to molecular species identification via PCR-Reverse Line Blot (RLB). Results: Prior to IVM treatment, 11 cyathostomin species were detected in faecal samples from TB horses enrolled in this study, i.e. Cyathostomum (Cya.) catinatum, Cylicostephanus (Cys.) longibursatus, Cys. goldi, Cylicocyclus (Cyc.) nassatus, Cys. calicatus, Cya, pateratum, Cyc. radiatus, Paraposteriostomum mettami, Coronocyclus (Cor.) labratus, Cyc. insigne and Cyc. radiatus variant A. Of these, eggs of Cya. catinatum, Cys. longibursatus, Cyc. nassatus and Cyc. radiatus could be detected at 28 days post-treatment, while from day 42 onwards, cyathostomin species composition reflected data obtained pre-IVM treatment, with the exception of eggs of Cor. labratus and Cyc. insigne that could no longer be detected post-IVM administration. Conclusions: This study provides valuable data on the occurrence of IVM-resistance in cyathostomins in the UK. Nevertheless, further investigations are needed to shed light on the prevalence and incidence of drug-resistance in this country as well as other areas of the world where equine trade is substantial

Dysbiosis associated with acute helminth infections in herbivorous youngstock – observations and implications

Abstract: A plethora of data points towards a role of the gastrointestinal (GI) microbiota of neonatal and young vertebrates in supporting the development and regulation of the host immune system. However, knowledge of the impact that infections by GI helminths exert on the developing microbiota of juvenile hosts is, thus far, limited. This study investigates, for the first time, the associations between acute infections by GI helminths and the faecal microbial and metabolic profiles of a cohort of equine youngstock, prior to and following treatment with parasiticides (ivermectin). We observed that high versus low parasite burdens (measured via parasite egg counts in faecal samples) were associated with specific compositional alterations of the developing microbiome; in particular, the faecal microbiota of animals with heavy worm infection burdens was characterised by lower microbial richness, and alterations to the relative abundances of bacterial taxa with immune-modulatory functions. Amino acids and glucose were increased in faecal samples from the same cohort, which indicated the likely occurrence of intestinal malabsorption. These data support the hypothesis that GI helminth infections in young livestock are associated with significant alterations to the GI microbiota, which may impact on both metabolism and development of acquired immunity. This knowledge will direct future studies aimed to identify the long-term impact of infection-induced alterations of the GI microbiota in young livestock

Dysbiosis associated with acute helminth infections in herbivorous youngstock:observations and implications

A plethora of data points towards a role of the gastrointestinal (GI) microbiota of neonatal and young vertebrates in supporting the development and regulation of the host immune system. However, knowledge of the impact that infections by GI helminths exert on the developing microbiota of juvenile hosts is, thus far, limited. This study investigates, for the first time, the associations between acute infections by GI helminths and the faecal microbial and metabolic profiles of a cohort of equine youngstock, prior to and following treatment with parasiticides (ivermectin). We observed that high versus low parasite burdens (measured via parasite egg counts in faecal samples) were associated with specific compositional alterations of the developing microbiome; in particular, the faecal microbiota of animals with heavy worm infection burdens was characterised by lower microbial richness, and alterations to the relative abundances of bacterial taxa with immune-modulatory functions. Amino acids and glucose were increased in faecal samples from the same cohort, which indicated the likely occurrence of intestinal malabsorption. These data support the hypothesis that GI helminth infections in young livestock are associated with significant alterations to the GI microbiota, which may impact on both metabolism and development of acquired immunity. This knowledge will direct future studies aimed to identify the long-term impact of infection-induced alterations of the GI microbiota in young livestock

The relationships between faecal egg counts and gut microbial composition in UK Thoroughbreds infected by cyathostomins

A growing body of evidence, particularly in humans and rodents, supports the existence of a complex network of interactions occurring between gastrointestinal (GI) helminth parasites and the gut commensal bacteria, with substantial effects on both host immunity and metabolic potential. However, little is known of the fundamental biology of such interactions in other animal species. Nonetheless, given the considerable economic losses associated with GI parasites, particularly in livestock and equines, as well as the global threat of emerging anthelmintic resistance, further explorations of the complexities of host-helminth-microbiota interactions in these species are needed. This study characterises the composition of the equine bacterial commensal flora associated with the presence, in faecal samples, of low (Clow) - and high (Chigh) numbers of eggs of an important group of equine GI parasites (i.e. the cyathostomins), prior to and following anthelmintic treatment. High-throughput sequencing of microbial 16S rRNA amplicons and associated bioinformatics and statistical analyses of sequence data revealed strong clustering according to faecal egg counts (P = 0.003). A trend towards increased populations of Methanomicrobia (class) and Dehalobacterium (genus) was observed in Clow in comparison with Chigh. Anthelmintic treatment in Chigh was associated with a significant reduction of the bacterial phylum TM7 14 days post-ivermectin administration, as well as a transient expansion of Adlercreuzia spp. at 2 days post-treatment. This study provides a first known insight into the discovery of the intimate mechanisms governing host-parasite-microbiota interactions in equids, and sets a basis for the development of novel, biology-based intervention strategies against equine GI helminths based on manipulation of the commensal gut flora

Resíduos de EBDCs e culturas com geração fitogênica de CS2.

A análise de resíduos etilenobis(ditiocarbamatos) (EBDCs) é realizada de maneira indireta, pela dosagem de CS2. Desse modo, plantas que geram fitogenicamente CS2, como as Caricaceas, podem fornecer resultados falso positivos. Todos os métodos de análise de resíduos de EBDCs são uma variação do método de Keppel (1969; 1971), que dosa o CS2 colorimetricamente. O CS2 também pode ser analisado por cromatografia gasosa, utilizando-se a técnica de análise por headspace, ou pela modificação desse método com a dissolução do CS2 em uma camada de solvente orgânico (iso-octano). O objetivo deste estudo foi analisar em amostras testemunha de mamão o nível de CS2 endógeno por três métodos distintos de análise de resíduos de EBDCs: iso-octano, headspace e espectrofotométrico. As concentrações de CS2 foram comparadas com o limite máximo de resíduos adotado pela União Européia (0,05 mg kg-1)

Tolerância para resíduos de EBDCs em culturas com geração fitogênica de CS2.

Neste trabalho foram utilizados três métodos para análise de ditiocarbamatos em amostras testemunha de mamão das variedades Golden, Sunrise solo e Tainung. Os mamões foram cultivados em áreas experimentais sem utilização, durante todo o ciclo da cultura, de agrotóxicos ou fertilizantes sulfurados. O CS2 foi quantificado por espectrofotometria e por cromatografia gasosa utilizando detector fotométrico de chama no modo enxofre, tanto no método por headspace quanto por partição em iso-octano. Todos os métodos forneceram resultados positivos de CS2 no mamão, independentemente da variedade avaliada. As concentrações de CS2 observadas foram comparadas com o limite máximo de resíduos de etilenobis(ditiocarbamatos)(EBDCs), estabelecido na Comunidade Européia em 0,05mg kg-1. A probabilidade de ser encontrada uma amostra de mamão com concentração de CS2 igual ou acima de 0,05 mg kg-1 foi de 12 % pelo método de iso-octano, 55% pelo método de headspace e 94 % pelo método espectrofotométrico. Desse modo, os resíduos de EBDCs quantificados como CS2, devem ser cuidadosamente interpretados em culturas com geração fitogênica de CS2, pois a presença deste não confirma a utilização de fungicidas EBDCs

Risco para desenvolvimento do diabetes mellitus em usuários da atenção primária a saúde: um estudo transversal

Objetivo: identificar o risco para o desenvolvimento do diabetes mellitus em usuários da atenção básica em um município do Sul do Brasil.Método: os dados foram coletados no período de outubro de 2013 a abril de 2014 com aplicação do Finnish Diabetes Risk Score em 189 usuários.Resultados: os resultados mostraram que a maioria dos entrevistados apresentou risco discretamente moderado e moderado (63,5%). Houve maior prevalência de alto risco para o gênero masculino. Entre as variáveis que apresentaram razão de prevalência significativa para o alto risco, encontram-se a idade, obesidade, circunferência abdominal, sedentarismo e histórico familiar de diabetes mellitus.Conclusão: a partir da identificação dos fatores de risco para o diabetes, destaca-se a importância da equipe de saúde na intervenção sobre os que podem ser modificados com o objetivo da prevenção da doença.Palavras-chave: Diabetes mellitus. Risco. Atenção primária à saúde