- Day:2016.01.14 03:28
Pig Transport During Cold Weather
During cool and cold weather, the main outcome is an increase in the rate of down pigs (also called fatigued, non-ambulatory-non-injured, NANI, stressed, subjects or suspects). The rate of NANI pigs can more than double in cool or cold weather. NANI pigs do not have the energy reserves to walk and sometimes even stand. In cold weather, this is observed more often.
Figure. Increase in NANI/down pig with cooler air temperatures. Taken from Sutherland et al., (2009).10 C represents about 50 F. Note the steady rise in NANI % below 10 C.
How do I know when pigs are too cold?
Pigs will be too cold when the air temperature is below 50 F (10 C). If bedding is used, you can take 10 F off that critical temperature. If pigs can huddle, another 10 F can come off the effective environmental temperature (the temperature that the pig “feels” or senses). Thus, at an air temperature of 30 F and with bedding and other pigs, the pigs will not be particularly cold. Cold pigs have a cool surface temperature to the touch and they will seek to huddle. If they can’t huddle with other pigs, they will shiver. When you see pigs shivering, they are especially cold.
Ambient temperature below which pigs should not be continuously showered in lairage.
Showering pigs with cold water during preslaughter lairage is thought to be useful in reducing the body temperature of hot, easily stressed animals. However, showering when the ambient temperature is too low could chill them too severely. To assess the effects of showering and to determine a temperature below which pigs should not be showered, pigs from one source, passing through a commercial slaughterhouse lairage, were split into two groups of approximately 50 each, showered and unshowered, on 10 days with a range of ambient temperatures. The pigs' behaviour and any damage to their skin were recorded, various measures of body temperature were taken before and after showering, and blood taken at slaughter was analysed for plasma creatine kinase, cortisol and lactate. Showering prevented the usual reduction in activity observed in pigs in lairage at high ambient temperatures. On the basis of the reduction in their flank temperature during showering, it is recommended that pigs should not be showered continuously if the temperature inside or outside the lairage falls below 5 degrees C, and showering should cease if they are seen to be shivering.