[Conditions of management and the construction of piggeries on pig-fattening farms as factors in the incidence of diseases of the lung and liver in slaughtered pigs (author's transl)].

All pigs passing along the slaughter-line in the slaughter-house of the Livestock and Meat Board of the Christian Farmers' Association of the Province of North Brabant are examined for the presence of lesions of the lung and liver. The proportions of animals without any severe lesions of the lungs and livers and the proportions of those with affected lungs, affected livers, condemned livers and pleurisy are reported every three months. Under the Animal Health Service of the Province of North Brabant, investigations were carried out on 251 farms with less than 10 per cent and 251 farm with more than 25 per cent of the animals with severe lesions of the lungs to study the effect of conditions of management on the incidence of diseases of the lung and liver. Among others, this produced the following results:--The average proportions of affected livers and those of the proportions of cases of pleurisy were higher, whereas the daily growth rate of each pig and the carcass quality were lower.--Slaughtered pigs with lesions of the lung and/or liver showed a significantly smaller daily growth rate during the fattening period. In pigs with pleurisy, retardation of growth was also observed on the breeding farm.--The proportion of affected lungs and livers is significantly affected by a number of factors on the farm. Among others, the following factors were found to be of importance: adopting the all in--all out system, removals, the origin of the piglets, the number of pigs in each compartment of the pig house and the construction of the piggery (width of pig house and slatted floor). Taking these factors into account, a "transverse housing system" is recommended.