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SUMMARY

A cross-sectional epidemiologic study associating air quality with swine health was conducted on 28 swine farms in southern Sweden. Correlation of housing air environment to swine diseases and productivity (data collected over the preceding 12 months) were investigated.

The most prevalent swine health problems detected at slaughter were pneumonia and pleuritis. In farrowing and nursery operations, the most prevalent problem was neonatal pig mortality. Several air contaminants (dust, ammonia, carbon dioxide, and microbes) were found to be correlated with these swine health problems. Maximal safe concentrations of air contaminants were estimated on the basis of dose-response correlation to swine health or human health problems. Recommended maximal concentrations of contaminants were: dust, 2.4 mg/m3; ammonia, 7 ppm; endotoxin, 0.08 mg/m3; total microbes, 105 colony-forming units/m3; and carbon dioxide, 1,540 ppm.

The overall quality of the ventilation system was correlated with lower concentration of ammonia, carbon dioxide, microorganisms, and endotoxin, but not with dust concentrations.

High animal density was related to high ammonia and air microbe concentrations. Animal density measured as kilograms of swine per cubic meter (compared with kilograms of pig weight or swine per square meter) had the highest correlation to animal health and air contaminants.

Free access
in American Journal of Veterinary Research

SUMMARY

The mycotoxin fumonisin B1 (FB 1) produced by Fusarium moniliforme in corn causes pulmonary edema in finishing swine. Effects of lower nonlethal amounts and effects in lactating sows with suckling pigs are unknown. An initial study was conducted to determine a nonlethal concentration of FB1 for lactating sows; whether ingested FB1 could be detected in the milk; and whether toxicosis could be detected in the pigs, as determined by necropsy. Another study was conducted to determine toxicosis in the pigs by measuring liver sphinganine-to-sphingosine ratio, and whether ingested FB1 affected T-lymphocyte function in sows and their pigs. Furthermore, sows of this study were maintained in controlled hot (27 to 32 C, 50 to 70% relative humidity) and thermoneutral (21 C, 55% relative humidity) environments to determine whether high temperature exacerbated the effects of FB1. In the first study, 100 μg of FB1/g of corn soybean meal diet was found to be nonlethal when fed for 14 days. Fumonisin B1 was not detected in the milk at 30 ppb and lesions were not found in the necropsied pigs, including 1 from a sow that died of porcine pulmonary edema syndrome after ingesting FB1 at a concentration of 175 ppm. In the second study, differences in liver sphinganine-to-sphingosine ratio of pigs were not found. Expressions of cell surface antigens on blood lymphocytes and lymphocyte proliferation response to various mitogens were not affected by FB1 or high temperature in sows or their pigs. The results indicated that when sows ingested nonlethal concentrations of FB1 for 17 days, there were no detectable amounts of FB1 in the sows' milk and no evidence of toxicosis in their pigs; no significant effect of FB1 on T-lymphocyte function in sows and pigs; and no enhanced toxic effects of FB1 attributable to high temperatures.

Free access
in American Journal of Veterinary Research

considered nontoxic to the environment. These materials are intended to mimic the favorable ballistic properties of lead yet cause minimal toxicosis, as measured by use of ingestion studies. 9,10 In an effort to adhere to federal and state regulations

Full access
in American Journal of Veterinary Research

suggested that these clinical variables are not useful for the purpose of diagnosing Fusarium mycotoxicoses in dogs. It is important that the mycotoxin challenge study of this report was conducted in an experimental environment in which exposure to

Full access
in American Journal of Veterinary Research

the generation of 17 homozygous mice, of which 6 females and 3 males were selected for proliferation. Mice were housed and reared in a specific and opportunistic pathogen–free 25 environment b and were then transferred to a facility c accredited by

Full access
in American Journal of Veterinary Research