Danger to pigs the due use to crushing can be reduced by of a simulated udder

Sows that lie on their young, pig "crushing", is a significant cause of pig mortality in current production systems. Although mortality rates of pigs in farrowing crates are lower than mortality rates of pigs in pens, loss du e to crushing is still estimated to be between 4.8 and 18%. During the firs t few days after parturition, pigs are highly attracted to the odor of thei r dam's udder. Thus, our research was designed to move the pigs away from t he sow by competing with the sow's udder using a "simulated" udder. Fifteen Yorkshire x Landrace sows and their litters (11.4 +/- .78 pigs) were assig ned to either a control (C, n = 9) or an experimental group (SU, n = 6). Th e C pigs had access to a heat lamp, whereas the SU pigs' crate had a simula ted udder. Data were collected using time-lapse photography (1 frame/.4 s) for a 3-d duration at the initiation of farrowing. When a sow stood, data w ere recorded by I-min scan samples to record the number of pigs using eithe r the heat lamp or the simulated udder. In addition, stillborn pigs, pig cr ushing, and death by other means also were recorded. Data were analyzed by 12-h periods using generalized estimating equations. Results indicate that from 12 to 72 h postpartum, excluding 24 to 36 h postpartum, the estimated probability that pigs were in a safe area (simulated udder or heat lamp) wa s .89 for SU pigs, compared with only .72 for C pigs (P = .005). During the 24- to 36-h period, it was more probable to find pigs on a simulated udder (.77) than under only a heat lamp (.61, P = .016). Stillborn pigs, pig cru shing, and death by other means were not different between treatments (mean = .87, .60, 1.2; P > .20). The simulated udder drew pigs away from the sow 's udder better than heat lamps alone. Considering these findings, mortalit y of pigs due to crushing may be decreased substantially using a simulated udder. These results are promising, but further refinement should be done, including improved udder design and investigation of the attractiveness of various stimuli.