Alarm Pheromones in Urine Modify the Behaviour of Weaner Pigs
Authors: Amory, J.R.; Pearce, G.P.
Source: Animal Welfare, Volume 9, Number 2, May 2000 , pp. 167-175(9)
Publisher: Universities Federation for Animal Welfare
Abstract:Pigs undergoing an alarming experience may produce olfactory stimuli (pheromones) in their urine, which may have consequences for the welfare of other pigs exposed to these stimuli. Twelve young adult female pigs (gilts) were restrained for 30min in feeding stalls (a potentially alarming experience) and any urine produced was collected. Six gilts had previously experienced the procedure (experienced gilts), and six gilts had not (inexperienced gilts). The gilts' behaviour was recorded over the 30min period. The inexperienced gilts exhibited significantly more escape behaviour (P < 0.001) and less exploratory behaviour (P < 0.05) than those which had prior experience of restraint.Twelve weaner pigs (30 days old) were subsequently individually exposed to the urine from inexperienced gilts, the urine from experienced gilts and a water control in an open field test. The ambulation score in the open field test was significantly higher (P < 0.01) when weaners were exposed to the urine from inexperienced gilts compared to the other two treatments. The weaners were then presented with a feeder containing feed sprayed with the treatment samples. The weaners took significantly longer to approach the feeder sprayed with the urine from the inexperienced gilts (P < 0.05) and performed Significantly more eating bouts (P < 0.05) that were significantly shorter compared with the water control (P < 0.05). Total number of vocalizations (P < 0.01) and grunts (P < 0.05) were Significantly greater in those pigs exposed to the inexperienced gilts' urine. These results indicate that urinary alarm pheromones were produced by the inexperienced gilts during restraint in the feeding stall and that these pheromones significantly modified the behaviour of weaner pigs subsequently exposed to them. Exposure to such pheromones is likely to adversely affect the welfare of pigs.
Document Type: Research article
Publication date: 2000-05-01