Factors associated with in-transit losses of market hogs in Ontario in 2001.

In-transit losses and stage of transport when deaths occurred were determined for 4 760 213 market-weight pigs produced in 2001 by 4159 Ontario producers and marketed through 117 transport companies to 33 packers located in Canada (96%) and the United States. Approximately 73% and 21% of producers marketed < 2000 pigs and < 500 pigs, respectively. In-transit loss was 0.017%, with 75% of producers losing < or = 5 pigs annually. Approximately half of in-transit losses occurred on the truck, with 14% of the other deaths occurring at the assembly yards, 4% on the producers' trucks, and 24% at the abattoir. Fifteen percent of in-transit deaths, representing 1212 pigs, occurred in pigs that were previously identified as abnormal by the transporter or personnel working at the assembly yard or abattoir. Average losses were higher for producers marketing < 2000 pigs, and in-transit loss ratio (ITLR) was highest among those marketing < 100 pigs. Pigs from small farms traveled greater distances than those from larger operations. In-transit losses increased sharply between 590 and 720 km traveled, and decreased at distances > 980 km. Environmental temperatures reached > or = 31degreesC for 4.2% of pigs shipped in June, July, and August, with median and mean temperatures of 20.6degreesC and 20.3degreesC, respectively, for these months. Twenty percent of all in-transit losses (1617 pigs) occurred in August.