Feeding behaviour of weaned pigs fed either pellets or meal: effects of the number of animals per feeding place

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Aerial dust concentrations in 12 pig houses

Aerial dust concentrations in 12 pig houses Dust concentration was measured during 3 days at hourly intervals in 5 farrowing houses and 7 fattening houses. The number concentration of aerial particles was measured using a counter which sizes the total numbers in 5 categories: from 0.3-0.5 mum to > 5 mum. The mean dust concentrations were significantly higher in the farrowing houses than in the fattening houses (179 +/- 91 vs 97 +/- 65 particles/ml). Over a 24-h period, the ratio between the highest and the lowest hourly concentrations was 3 +/- 1 in the farrowing houses and 5 +/- 4 in the fattening houses; the difference between the 2 types of houses is significant. The smallest particles were the most numerous; 82 % of the aerial particles were in the size range 0.3-0.5 mum, with less than 1 % being 5 mum or larger. During the most polluted hours, there was proportionally more particles in the size range 0.5-1 mum and significantly less particles in the size ranges 1-2 mum and 2-5 mum, as compared to the less polluted hours. This study shows that most of the aerial particles in piggeries are smaller than 5 mum, the size below which deposition is regarded to occur in the lower respiratory tract, the farrowing houses being more polluted than the fattening houses

Analysis of microclimate in calf housing heated and ventilated by unit heater

Temp. inside calf pens 4 x 4 m and 3 m high holding 5 calves was measured using sensors connected to a datalogger. Pens were heated by a pulsed air system with a constant flow of 500 m/h and max. power of 8860 kcal/h, using external air heated by a water-air heat exchanger. Pulsed air could therefore be heated from -15 to +39C. Interference between natural and artifical ventilation was noted. Openings designed as air outlets also acted as inlets, with a detrimental effect on air exchange. Inside temp. was always below the optimum. Warm air from the heater mixed badly with internal air, creating large temp. gradients. Heating and ventilation with the same equipment was not recommended

Effet de l'incorporation à la ration de bromure de Potassium sur les comportements de repos et de chevauchement de taurillons culards en stabulation libre

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Effect of 2 yucca extracts on the reduction of ammonia concentrations from pig slurry

The effects of two commercial yucca extracts on the ammonia release from pig slurry have been tested in laboratory and in one fattening house. In laboratory, tests were carried on with 4 litre samples whose ammonia production was recorded during 35 days. One of the two products, at the factory recommanded dose of 5 g/l, has successfully lowered the ammonia emission rate of the slurry. In the pig house, the two same products were given in the pigs' diet at the dose of 160 and 200 g/ton of feed. Inside a same building, pigs of one room received feed plus yucca extracts and those of the second room feed alone; none of the 2 products has significantly reduced the ammonia concentrations recorded on a three month period. One can expect improvements of the yucca extracts but up to now no guaranty can be given of their efficiency

Comparaison de l'utilisation de sciure ou d'un mélange paille-sciure comme matériau de litière accumulée pour porcs charcutiers

International audienc

Interpretation of temperature and humidity measurements in a calf house

Respiratory disorders were frequently observed in a calf house despite vaccinations and drug therapy. The building was heated with a hot air system and ventilated with extraction fans. Temperature and relative humidity were recorded over a 2-week period. Temperature was in agreement with usual recommendations but relative humidity was about 100% during the whole observation period. The high relative humidity was not due to an inadequate ventilation rate but the result of large amounts of water used daily in cleaning the building

La litière biomaîtrisée en élevage porcin

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