Pig Husbandry Practices Research Articles

Genome‐wide single nucleotide polymorphism analysis reveals recent genetic introgression from domestic pigs into Northwest European wild boar populations

Present-day genetic introgression from domestic pigs into European wild boar has been suggested in various studies. However, no hybrids have been identified beyond doubt mainly because available methods were unable to quantify the extent of introgression and rule out natural processes. Genetic introgression from domestic pigs may have far-reaching ecological consequences by altering traits like the reproduction rate or immunology of wild boar. In this study, we demonstrate a novel approach to investigate genetic introgression in a Northwest (NW) European wild boar data set using a genome-wide single nucleotide polymorphism (SNP) assay developed for domestic pigs. We quantified the extent of introgression using allele frequency spectrum analysis, in silico hybridization simulations and genome distribution patterns of introgressed SNPs. Levels of recent introgression in the study area were expected to be low, as pig farming practices are prevailingly intensive and indoors. However, evidence was found for geographically widespread presence of domestic pig SNPs in 10% of analysed wild boar. This was supported by the identification of two different pig mitochondrial DNA haplotypes in three of the identified hybrid wild boar, suggesting that introgression had occurred from multiple sources (pig breeds). In silico hybridization simulations showed that the level of introgression in the identified hybrid wild boar is equivalent to first-generation hybrids until fifth-generation backcrosses with wild boar. The distribution pattern of introgressed SNPs supported these assignments in four of nine hybrids. The other five hybrids are considered advanced-generation hybrids, resulting from interbreeding among hybrid individuals. Three of nine hybrids were genetically associated with a different wild boar population than the one in which they were sampled. This discrepancy suggests that genetic introgression has occurred through the escape or release of an already hybridized farmed wild boar stock. We conclude that genetic introgression from domestic pigs into NW European wild boar populations is more recent and more common than expected and that genome-wide SNP analysis is a promising tool to quantify recent hybridization in free-living populations.

Prevalence and Risk Factors of Porcine Cysticercosis in Angónia District, Mozambique

Taenia solium is an important zoonosis in many developing countries. Cysticercosis poses a serious public health risk and incurs sizeable economic losses to pig production. Because data on the epidemiology of porcine cysticercosis in Mozambique are scarce, the present study was conducted to determine the prevalence and risk factors for porcine cysticercosis. A cross-sectional survey was carried out in 11 villages in Angónia district, Tete province in northwestern Mozambique. Between September and November, 2007, a total of 661 pigs were tested serologically and examined by tongue inspection. Serum samples were tested for the presence of circulating parasite antigen using a monoclonal antibody-based sandwich enzyme-linked immunosorbent assay (Ag-ELISA). In addition, a questionnaire survey to collect information on pig production, occurrence and transmission of porcine cysticercosis, risk factors and awareness of porcine cysticercosis was conducted in the selected households from which pigs were sampled. Two hundred thirty-one samples (34.9%) were found positive by the Ag-ELISA, while by tongue inspection on the same animals cysticerci were detected in 84 pigs (12.7%). Increasing age (OR = 1.63; 95% CI = 1.13–2.37) and free-range pig husbandry system (OR = 3.81; 95% CI = 2.08–7.06) were important risk factors for porcine cysticercosis in the district. The present findings indicate that porcine cysticercosis is endemic in the region, and that increasing pig age and pig husbandry practices contribute significantly to porcine cysticercosis transmission. Further epidemiological studies on the prevalence and transmission of porcine cysticercosis in rural communities in Mozambique are needed to enable collection of more baseline data and implementation of effective control strategies within the country.

Isotope analysis of human and animal diets from the Hanamiai archaeological site (French Polynesia)

AbstractWe report the first palaeodietary stable isotope study of humans and animals from an East Polynesian archaeological site. The Hanamiai Dune in the Marquesas Islands of French Polynesia has a long stratigraphy (ca. 1025 AD to 1850 AD). We obtained carbon and nitrogen isotope values for a wide range of terrestrial and marine species from different cultural layers. We also analyzed four human teeth representing four different individuals. Pigs, rats and dogs from the initial occupation phases had isotope signatures indicating marine protein consumption, probably linked to the consumption, and subsequent extinction, of indigenous seabirds. We found evidence of different pig husbandry practices, with some pigs having an almost entirely marine diet. Humans, surprisingly, did not have a mainly marine diet but likely derived the majority of their protein from eating terrestrial mammals such as pigs, as well as perhaps dogs and rats.

Neurocysticercosis : a possible cause of epileptiform seizures in people residing in villages served by the Bethanie clinic in the North West Province of South Africa

A study to detect human taeniasis and cysticercosis was conducted in 4 village communities served by the Bethanie clinic in the North West Province, based on reports of people being diagnosed there with epileptiform episodes. Many home owners in the villages rear pigs in small numbers for both meat availability and an immediate income from live pig or pig meat sales. The primary aim of the work was to conduct in the study area a census of all small scale pig producers and a survey of rural village consumers, both by means of a structured questionnaire. The former reviewed pig husbandry practices, slaughter and marketing of pigs and the latter provided information on pork consumption, sanitation as well as people's basic knowledge of Taenia solium. Stool samples from consenting participants were screened by a contracted approved laboratory for IR solium. A descriptive analysis of retrospective data was conducted at the Bethanie clinic to determine the proportional morbidity of neurocysticercosis from the medical records of patients diagnosed with seizures in an attempt to establish possible sources of infection and routes of transmission. In addition, the total pig population in the study area was determined more accurately and the prevalence of cysticercosis investigated in pigs subjected to meat inspection at an approved abattoir. The questionnaires revealed a poor understanding of the disease, poor sanitation and hygiene, poor methods of pig husbandry and poor meat inspection and control in rural smallholder communities. There was no significant statistical difference in the proportion of households reporting evidence of epilepsy and owning pigs and those that did not. There is a strong evidence of a tendency towards an association between epilepsy, consumption habits and some identified epidemiological risk factors.

The prevalence of porcine cysticercosis in Eastern and Southern provinces of Zambia.

The objective of this study was to determine the prevalence and importance of porcine cysticercosis in rural areas of Zambia. The study involved an abattoir survey of 1316 pigs at a slaughter slab in Lusaka and two field surveys in villages in Southern and Eastern provinces. Lingual examination of live pigs and visual inspection of their carcass as well as blood sampling for measuring circulating parasite antigen by enzyme-linked immunosorbent assay (Ag-ELISA) were used as parameters to measure infection. In the field surveys, a questionnaire was administered to every household whose pigs were examined to obtain information on pig husbandry practices and to study risk factors for the infection. Out of the 1316 pigs examined at the slaughter slab, 143 (10.9%) and 271 (20.6%) were positive by lingual examination and meat inspection, respectively. Most of the pigs were very heavily infected with predominantly live cysts. The field surveys revealed that eight (8.2%) out of 98 pigs from Southern province and eight (5.2%) out of 151 pigs from Eastern province were positive for cysticercosis by tongue palpation. Using the Ag-ELISA 20 (20.8%) and 14 (9.3%) pigs were positive in Southern and Eastern provinces, respectively. The questionnaire survey revealed poor pig husbandry practices, absence of meat inspection and control, poor knowledge of the disease and poor sanitation in the surveyed villages. The prevalence of pig cysticercosis found in this study ranks among the highest in the southern African region, in Africa and in the world. The current study suggests the presence of human tapeworm carriers and a high risk of human cysticercosis in the surveyed areas as well as in urban centres where pigs from rural areas are increasingly sold, slaughtered and consumed.

“we must follow the Fore”: pig husbandry intensification and ritual diffusion among the Irakia Awa, Papua New Guinea

Pig husbandry intensification is part of the Irakia Awa response to problems engendered not by population growth, but by changes in the regional political economy under colonialism. Restructured political relations and expansion of the market economy have led to an acceleration of intergroup exchange activities and increased demands by affines and exchange partners for transactions in money and pigs, changes that threaten the prestige and economic well‐being of Irakians. After careful consideration of possible remedial actions, Irakian clan members decided to adopt the more intensive pig husbandry and ritual practices of neighboring Fore peoples and to compete with each other in an effort to raise more pigs for exchange. Initial results show that while the village herd size was increased by 29 percent in 12 months, the several Irakian clans experienced varied degrees of success. Also, expansion of the village herd created new social problems that required additional adjustments in the community life‐style. The responses of the Irakia Awa illustrate the complex social processes involved in the intensification of local production systems. [pig husbandry, production intensification, social change, Papua New Guinea]