EFFECTS OF ATROPHIC RHINITIS AND CLIMATIC ENVIRONMENT ON THE PERFORMANCE OF PIGS

Effects of subclinical atrophic rhinitis and exposure to adverse clima tic conditions on partitioning of energy (metabolism) and performance in pigs under field-like conditions were determined. Eight groups of 3 0 5-week-old pigs each, were assigned to a 2 X 2 factorial arrangement of treatments: to 0 or 13 mu g/ml of Pm-T challenge-exposure, and to a thermoneutral or adverse (below thermoneutrality with draught period s) climatic environment. Climatic treatment lasted 5 weeks. Subsequent ly, pigs were fattened till 100 kg live weight. All Pm-T exposed pigle ts had moderate nasal damage, which was not affected by climatic treat ment. The adverse climatic environment resulted in a lower amount of e nergy available for production due to an increased maintenance require ment (57 kJ kg(-0.75)) and to a lower food intake (76 g/d). This resul ted in growth retardation (86 g/d). The Pm-T administration did not ch ange metabolizability and maintenance requirements of energy. The slig ht growth retardation with Pm-T (17 g/d) was thought to be the outcome of a lower food intake (34 g/d). Both treatments and their interactio n affected D-100 kg (days to reach 100 kg body weight). Pm-T treated a nd control pigs from the good environment differed 3 days in D-100 kg, while for those groups from the adverse environment this difference w as 8 days.