Factors associated with in-transit losses of fattening pigs

Abstract In-transit losses (ITL) in fattening pigs refers to mortality occurring after having left the farm but prior to stunning at the abattoir. The purpose of this observational study was to identify the associations between environmental and truck temperatures, distances travelled, feed withdrawal, farm, transport company and abattoir and in-transit losses of fattening pigs marketed in Ontario, Canada from 2001 to 2004. A prospective study of 104 trips was conducted to determine temperatures inside the truck and identify the factors associated with this. In 2001, ITL was 0.017%, with 75% of producers losing < 5 pigs annually. In-transit losses increased between distances travelled of 590 to 720 km and decreased at distances greater than 980 km. The Pig Comfort Index, a combination of temperature and humidity, was used to identify thresholds of environmental conditions above which in-transit losses increased. The farm at which the pig was raised explained more variation of ITL (25%) than transport company (8%) or abattoir (16%). The within-farm ITL in 2003 had a positive association with those in 2001 and 2002. Withdrawing food prior to transport may decrease ITL on some farms. The temperature in truck compartments holding pigs increased by 0.99°C as the environmental temperature increased by 1°C and by 0.1°C as the relative humidity increased by 1%. Truck temperature decreased 0.06°C for each increase in driving speed of 10 km h −1 and increased by 7°C with an increase in pig density from one to 2.6 pigs per m 2 .