OLAQUINDOX TOXICITY IN PIGLETS

On a large scale pig herd a premix containing 1% olaquindox was used t o treat and prevent enteral diseases in weaned piglets. Estimated amou nts of the preparation were sprinkled over the feed of the piglets ove r several weeks thus it is difficult to assess the exact quantities of the active component that was taken up by the animals. Two to three w eeks after weaning the majority of the animals showed inappetence, lac k of weight gain and cachexia, exsiccosis, defecation of a berry-like faeces, pica, urine-drinking, cannibalism, anaemia, trembling of skin muscles, weakness of the hind quarters, and became recumbent after whi ch they died within a couple of days. Mortality ranged between 10 and 30% in various batches. The surviving pigs reached only 20 to 70 kg by the end of the fattening period. At necropsy, empty stomach and small intestine, in the stomach sometimes peptic ulcers, in the large intes tine dense, ball-like contents covered with mucus, furthermore atrophy of the adrenal glands and congestion in parenchymal organs were to be seen. Histological examination revealed atrophy of the adrenal cortex , affecting principally the aldosterone-producing zona arcuata (Fig. 1 -4), as well as hypertrophy of the adrenal medulla, thus there was a c hange in the normal cortex/medulla ratio (Table).