Intensive Piggeries Research Articles

English

Uganda is currently among the largest per capita consumers of pork in sub Saharan Africa. Most of this pork is consumed in “pork joints” in Kampala and other major urban centers in the country. However, the current productivity is low and cannot meet the soaring demand for pork. No information was previously available on the performance productivity of intensive piggeries in Uganda. This study was aimed at assessing the performance, factors affecting productivity and challenges to intensive pig farming in peri-urban Kampala. Production parameters were captured from purposively selected 332 sows and 521 grower pigs. Information on management practices, challenges and prospects of the industry was gathered through questionnaires administered to farmers, key informant interviews and stakeholder’s focus group discussions. Results showed most farms had good level of management but the breeding practices were uniformly erratic in all the farms, and different breeds were crossed anyhow. Furthermore both reproduction and performance parameters were suboptimal. Analysis of management practices revealed that breed had a significant effect on growth performance (p < 0.001) and litter size (p < 0.005). Feeding had significant effects on litter size (p < 0.001), number weaned (p < 0.01), weight:age ratio (p < 0.05) and weaning to service interval (p < 0.05). The major constraints found were high feed costs, diseases and competition for land with the upcoming residential estates. The performance indices varied greatly between farms, indicating great potential for improved productivity. We recommend improved housing, breeding practices, feeding and biosecurity measures so as to improve on performance and productivity of peri-urban pig farming. Key words: Peri-urban farming, pig production, performance indices, management systems, challenges.

Molecular epidemiology of Blastocystis in pigs and their in-contact humans in Southeast Queensland, Australia, and Cambodia

Blastocystis, an intestinal protist commonly found in humans and animals worldwide, has been implicated by some as a causative agent in irritable bowel syndrome in humans. In pigs, infection with Blastocystis is commonly reported, with most pigs shown to harbour subtypes (ST) 1 or 5, suggesting that these animals are potentially natural hosts for Blastocystis. Although ST5 is considered rare in humans, it has been reported to be a potential zoonosis from pigs in rural China. To test these hypotheses, we conducted molecular analysis of faecal samples from pigs and in-contact humans from commercial intensive piggeries in Southeast Queensland (SEQ), Australia, and a village in rural Cambodia. The prevalence of Blastocystis in SEQ and Cambodian pigs was 76.7% and 45.2%, respectively, with all positive pigs harbouring ST5. It appears likely that pigs are natural hosts of Blastocystis with a high prevalence of ST5 that is presumably the pig-adapted ST in these regions. Amongst the SEQ piggery staff, 83.3% were Blastocystis carriers in contrast to only 55.2% of Cambodian villagers. The predominant STs found in humans were STs 1, 2 (Cambodia only) and 3. Interestingly, ST5 which is usually rare in humans was present in the SEQ piggery staff but not in the Cambodian villagers. We conclude that in intensive piggeries, close contact between pigs and their handlers may increase the risks of zoonotic transmission of Blastocystis.

Analysis of Air Pollution from Swine Production by Using Air Dispersion Model and GIS in Quebec

Swine production, the second most important contributor to Quebec's agricultural revenue, faces many problems. Intensive piggeries, with up to 599 animal units, are used to raise finishing pigs for slaughter. Among the great number of gaseous species emitted to the atmospheric environment from livestock buildings and manure storage units is NH3, which is one of the most important and most offensive with respect to human health. Under appropriate meteorological and topographical conditions, gaseous contaminants can spread and cause a public nuisance--up to a 1-km radius around the farm. To mitigate these effects, the Quebec Government adopted regulations that set minimum buffer distances to be observed by any expansion of an existing or new pig farm. The objectives of this study were (i) to assess the efficiency of the current buffer distance prescriptions in Quebec in mitigating effects of air pollution from swine units and (ii) to identify potential areas for establishing pig farm operations that will not be offensive to people. The air dispersion American Meteorological Society/Environmental Protection Agency Regulatory Model (AERMOD) with receptors distributed at 1.6 km around each source was used first, followed by a spatial geographic information system (GIS) model. Results from the dispersion model showed that the highest hourly concentration with a 99.5% compliance frequency for a single farm was 3078.1 microg/m3 and exceeded the NH3 odor criterion hourly standard set by the Quebec Government at 183.4 microg/m3. Thus, for public safety, densely populated areas like housing developments must be located >1300 m from a pig farm. This distance is in the range of setback distances (723 to 1447 m) obtained by using abacuses defined in the L'Erable Regional County Municipality. That is why we can say the current rules established by the Quebec Government, if rigorously applied, can prevent odor nuisance, due to NH3 emission, from swine farms. In the spatial model, buffer zones were established around houses, roads, waterways, and drinking water intakes. By combining layers of information in the ArcGIS Model Builder, potential areas in which pig farms can be installed, without public odor nuisance, were identified.

Pu'aka Tonga

Pu'aka Tonga

Absorption of artificial piggery effluent by soil: A laboratory study

Urine, faeces, and waste feed flushed from pens of intensive piggeries produce large volumes of nutrient-rich effluent, which is often most productively used for irrigation. These effluents tend to be similar, with pH values in the range 7.6–8.0 together with high water-soluble ammonium and potassium but lower concentrations of calcium, sodium, and magnesium. There is little experimental information on the behaviour of these mixed ion systems in soils, so the effects of artificial but chemically similar effluents were examined in absorption experiments on columns of ‘natural’ soils. In one series of experiments, NH4+ was excluded from the artificial effluent to assess the consequences of its presence or absence. Water content and solute concentration data scaled according to distance divided by the square root of time in experiments terminated at different times. This showed that basic flow and reaction equations were valid and that water-soluble and exchangeable cations appeared to be in equilibrium in the ‘time-scale’ of absorption. Systematic patterns of behaviour emerged: chloride, the dominant anion in the absorbed solution, moved with the water and its front coincided with the piston front that would exist if the absorbed water completely displaced the original soil solution; cation exchange was restricted to the inflow end of the columns in an environment of constant Cl– concentration and was retarded relative to the moving water. High concentrations of NH4+ appeared not materially to affect the exchange isotherms of other cation pairs, although they reduced retardation of other exchangeable cation fronts. The method provides a useful way to define exchange isotherms in an appropriate environment of competing cations.

Studies on preweaning piglet diarrhoea

The aim of this study was to determine the cause and risk factors involved in preweaning piglet diarrhoea. Faecal samples from 2380 diarrhoeic piglets, 5 to 30 days of age, were examined for enteropathogens. Isospora suis oocysts were detected in 53.8% of samples, Escherichia coli in 18.2% and rotavirus in 16.9%. I suis had the widest distribution, being present on 70.9% of 151 piggeries. The onset of diarrhoea occurred mainly between 7 and 14 days (77.5%), peaking at 10 days. Records of 4086 litters from two intensive piggeries were analysed and showed no seasonal variation or effect of sow parity on the incidence of piglet diarrhoea. I suis was the most common enteropathogen associated with diarrhoea in piglets from 5 days of age until weaning.

Rotavirus excretion by village pigs in Papua New Guinea

Cohort studies were conducted on 29 pigs from 3 villages in the Highlands of Papua New Guinea. Animals ranged in age from 9 d to 5 m old. Three hundred and twenty nine faecal samples were collected from individual pigs followed over 3 to 6 w periods, and were examined for group A rotavirus antigen by ELISA, and rotaviral genomic RNA by polyacrylamide gel electrophoresis (PAGE). Electron microscopy was also conducted on selected samples. Group A rotavirus was detected in the faeces of 16 pigs with infected individuals coming from all villages. Non-group A rotavirus resembling group C was found in faeces from pigs from 2 villages. All of the group A rotaviruses examined had the same electrophoretype and this was distinct from that of the common type infecting humans in the area at the time of the study. None of the group A positive samples reacted with monoclonal antisera specific for human group A rotaviruses of serotypes 1, 2, 3, 4, or 8. The non-group A rotaviruses also all had identical electrophoretypes. In contrast to previous findings in intensive piggeries, rotavirus infection did not occur in all young pigs and was not limited to young animals under 2 m of age. Infected pigs varied in age from 12 days to 20 weeks of age. This pattern of infection was attributed to the non-intensive husbandry situations in the villages, with less opportunity for transmission to occur than in intensive piggeries.

Melioidosis in intensive piggeries in south eastern Queensland.

The epidemiology of melioidosis was investigated in 8 intensive piggery units which used water from the same river in south eastern Queensland. In 3 consecutive years cases of disease followed heavy rainfall and flooding. Although Pseudomonas pseudomallei was not isolated from water or soil samples the water supply was suspected as the source of infection. Affected pigs were detected at slaughter by the presence of abscesses most commonly in the bronchial lymph nodes (40%) and spleen (34%). One hundred and fifty nine cases were observed at slaughter from a total of 17,397 animals at risk. Infection by inhalation of water aerosols derived from nipple drinkers, hose sprays and a water misting cooler was considered to be responsible for the bronchial lymph node lesions. These outbreaks occurred outside the area in which melioidosis is generally regarded as being endemic.