Long duration transport of pigs is an important welfare issue world-wide. Current transportation legislation in the United States dictates that animals cannot be transported over 28 h without being rested and given food and water; however there is limited information available on the acute physiological effects of long distance transport on pigs. The objective of this study was to evaluate the effects of a 6, 12, 18, 24, or 30 h transport period on the physiology of breeding age gilts. Eight weight matched gilts were allocated to one of 15 treatment groups. Treatments included: Gilts that remained in their home pen for 6, 12, 18, 24, or 30 h (CON); Gilts that were transported for 6, 12, 18, 24, or 30 h at the transport quality assurance guidelines specified space allowance (TQA); or Gilts that were transported for 6, 12, 18, 24, or 30 h at the TQA specified space allowance plus 20% extra space (TQA+). Every 6 h, pigs in one pair of compartments (TQA and TQA+) were removed from the trailer (after a 6, 12, 18, 24, or 30 h transport period). Blood samples and body weights were collected from gilts and their respective controls before and after transport. The granulocyte to lymphocyte ratio was greater in TQA and TQA+ gilts transported for 6 h compared with controls. The percentage of lymphocyte and granulocytes, platelet counts, hemoglobin, and hematocrit concentrations were affected by transport and the duration of transport. Total white blood cell and lymphocyte counts were lower and albumin, glucose, total bilirubin, and total protein concentrations were greater in TQA and TQA+ compared to controls regardless of transport period. Creatine kinase concentrations were greater in TQA compared with controls. Percent body weight was decreased in TQA and TQA+ gilts after a 6, 12, 18, 24, and 30 h transport period compared with controls. Physiological measures of acute stress were observed in transported gilts (TQA and TQA+) after a 6 h transport period, but then returned to similar levels as non-transported control gilts. Physiological measures of dehydration and muscle breakdown were observed in gilts after transport, regardless of transport duration. Overall, these data indicate that gilts transported for a period of up to 30 h experience acute stress and changes in homeostasis probably due to dehydration, food deprivation, and transport. 

To view this complete article please visit: http://www.journals.elsevierhealth.com/periodicals/livsci/