The combined effects of transport and food and water deprivation on the physiology of breeding age gilts

The objective of this study was to evaluate the effects of a 6, 12, 18, 24, or 30h transport period on the physiology and reproductive success of breeding age gilts, simulating transport of breeding gilts from one farm to a commercial breeding herd. Fifty gilts were allocated to one of five transport (TRANS) treatment groups; transported for 6, 12, 18, 24, or 30h. Fifteen gilts were allocated to one of five control (CON) treatments; gilts remained in their home pen for 6, 12, 18, 24, or 30h. Every 6h, gilts from one TRANS treatment were removed from the trailer. Blood samples were collected from gilts and their respective controls before and after transport. Gilts were then bred after puberty. The granulocyte to lymphocyte ratio (P<0.05) and cortisol concentrations (P<0.07) were greater in TRANS compared with CON gilts after a 6 and 12h transport period. Albumin concentrations were greater (P<0.001) in transported gilts after an 18 and 30h transport period compared with CON gilts. Blood urea nitrogen, glucose, and total protein concentrations were greater (P<0.05) in transported gilts compared with controls, regardless of the transport period. Reproductive performance measures did not differ (P>0.05) among treatments regardless of the length of transport duration. These data indicate that gilts transported for a period of up to 30h experienced initial acute stress during the first 6 to 12h and changes in water homeostasis throughout the 30h journey due to dehydration, food deprivation, and transport, however reproductive measures suggest that the long-term homeostasis of the gilts in this study were not significantly compromised. Transport of breeding gilts induced acute, transient stress but did not negatively impact reproductive performance. Interestingly, gilts were more at risk of physiological perturbations when transported 6h or less than 12 to 30h.