EPIDEMIOLOGICAL ASPECTS OF A FOCUS OF Tunga penetrans INFESTATION IN OUTDOOR PIG PRODUCTION

Abstract

The outdoors intensive-type pig production is characterized by maintaining swine during reproductive, pregnancy and nursing periods on pasture limited by wiring and/or electric fences. The aim of the present report was to describe the epidemiological aspects of an outbreak of Tunga penetrans in an outdoor pig production system. A total of six mature boars, 9 lactating sows, 13 pregnant sows, 9 mating sows, 20 suckling pigs and 34 weaned pigs were clinically examined. None of the boars were infested, while 50% of all sows examined had the parasite lesions, most frequently observed in the breast area, thus resulting in agalactia in lactating sows due to obstruction of the galactophorus channel, with subsequent involution of the mammary gland. In 90% of suckling piglets walking difficulty was observed, caused by the presence of the parasite in the hoofs, with 25% of these animals also showing hock lesions (farm number 1, n = 48). Similar lesions were observed in 100% of 40-47 days old weaned pigs (farm number 2, n = 24) and in 80% of 70 days old weaned pigs (farm number 3, n = 10), all of which had been transferred to finishing units in a confinement system. Therefore we conclude that Tunga penetrans can infest pigs reared or kept outdoors, causing agalactia in lactating sows, and walking disorders in suckling and weaned pigs.

KEY-WORDS: Chiggers, agalactia in sows; outdoors pig production.