Pruritus and behavior of pigs infested by itch mites, Sarcoptes scabiei (Acari: Sarcoptidae)

Effects of infestation by Sarcoptes scabiei (De Geer) on pruritus and other behaviors of pigs for 9-13 wks after weaning were evaluated. Regardless of the dose of mites inoculated, pigs fed ad lib. spent approximately 60% of their time at rest. Within their average day, pigs spent more time eating in morning and evening, were more active and pruritic at midday, and rested more and spent the least time drinking water at night. Mite infestations increased total activity and time spent scratching and rubbing. Infested pigs sprayed with water rubbed and scratched 4-10 times more frequently than those left undisturbed or disturbed by other means. Pigs receiving inoculating doses of 1,000 mites became more pruritic than pigs receiving 100 mites, and both groups developed more pruritus than non-infested control pigs.