RESUMO
OBJECTIVE: Lao PDR's recent accession to the World Trade Organization necessitates a greater understanding of the patterns and risk of livestock production in order to better align national policy with the Agreement on the Application of Sanitary and Phytosanitary Measures. This eco-health study was conducted to improve understanding of the interrelations between market chains and zoonotic infection risks at two strategic cross border points between Lao PDR, Thailand and Viet Nam. METHODS: Information gained from smallholder farmer/trader interviews was integrated with serological surveys for pig-associated zoonoses-including hepatitis E virus (HEV), Taenia solium (T. solium) and trichinella-to identify potential linkages between disease risk and pig production and slaughter in low input systems common across the country. RESULTS: Trichinella and HEV exposure was high in both humans and pigs in both study areas, significantly associated with pig slaughter and the subsequent consumption and handling of raw pork products. T. solium demonstrated a strong geographical and ethnic association with the northern study area bordering Vietnam. With the right knowledge and accessible, affordable inputs, the majority of smallholder farmers indicated a willingness to invest more in pig production, which could simultaneously improve livelihoods and decrease exposure to HEV, Trichinella, and T. solium through increased access to formal markets and an improved slaughter processes. CONCLUSION: The linkages identified when assessing disease risk in the context of potential economic and cultural drivers of transmission highlight the importance of a systems-based approach for the detection and control of zoonotic disease, and contributes to an improved understanding of the Lao PDR livestock sector.
RESUMO
The Y chromosome carries information about the demography of paternal lineages, and thus, can prove invaluable for retracing both the evolutionary trajectory of wild animals and the breeding history of domesticates. In horses, the Y chromosome shows a limited, but highly informative, sequence diversity, supporting the increasing breeding influence of Oriental lineages during the last 1500 years. Here, we augment the primary horse Y-phylogeny, which is currently mainly based on modern horse breeds of economic interest, with haplotypes (HT) segregating in remote horse populations around the world. We analyze target enriched sequencing data of 5 Mb of the Y chromosome from 76 domestic males, together with 89 whole genome sequenced domestic males and five Przewalski's horses from previous studies. The resulting phylogeny comprises 153 HTs defined by 2966 variants and offers unprecedented resolution into the history of horse paternal lineages. It reveals the presence of a remarkable number of previously unknown haplogroups in Mongolian horses and insular populations. Phylogenetic placement of HTs retrieved from 163 archaeological specimens further indicates that most of the present-day Y-chromosomal variation evolved after the domestication process that started around 4200 years ago in the Western Eurasian steppes. Our comprehensive phylogeny significantly reduces ascertainment bias and constitutes a robust evolutionary framework for analyzing horse population dynamics and diversity.