Pathological lesions in swine at slaughter. V. Pathological lesions in relation to some environmental factors in the herds.

The influence of environment on animal health was studied in 40 bacon herds. These herds delivered approx. 11,000 baconers annually to the slaughter-house. The data from the meat inspection was studied in connection with the environmental recordings, and the relationship between 18 lesions and 20 environmental factors were estimated by statistical methods. The data was collected in the period 1975–1977. The influence of environmental factors upon the prevalence of different lesions showed considerable variation. Ten environmental factors were significantly associated with pleurisy and tail lesions (cannibalism). On the other hand none of the environmental factors bore any significant relation to atrophic rhinitis, pericarditis, peritonitis, perihepatitis, polyarthritis, arthritis and claw lesions. Eight environmental factors influenced the proportion of healthy animals. The recorded environmental factors influenced the overall health situation to a varying degree. For example, design of pen walls, insulation of pen floors, occasional use of supplementary feed and free access to drinking water were related to 5–7 lesions, while the nature of the concentrate (meal/pellets) had no significant influence. The study indicated that many details in environment and management could be of importance to the health of bacon pigs. However, statistical analysis also showed that production systems had a considerably stronger influence upon the health situation than any of the “pure” environmental factors – even when these factors were added.