Submitted to: Research Workers in Animal Diseases Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 12/4/2005
Publication Date: N/A
Technical Abstract: Long distance transports may significantly affect the health of pigs; thus, adding a rest stop (lairage) during long journeys may improve their well-being. The objective of this study was to determine whether a mid-journey lairage was beneficial or detrimental to swine immune variables during a 16-h transport. Two replications were conducted, one in January and the other in April. Eighteen kg pigs were housed in 16 pens (13-16 pigs/pen) with 8 pens/treatment. In the lairage (La) treatment, pigs were transported for 8 h, given a rest with food and water for 8 h, then transported 8 h. In the continuous (Co) treatment, pigs were continuously transported for 16 h. Jugular blood was collected from 16 pigs (8/treatment) on d 1, 3, 7 and 14 post-transport. White blood cell counts, neutrophil cell functions (phagocytosis and oxidative burst), and phenotypic cell markers CD14 and CD18 were analyzed using flow cytometry. In both replications, Co pigs had greater granulocyte counts and larger granulocyte percentages on d 1 (P<0.05). Additionally, the La pigs, had larger lymphocyte percentages on d 1 in April (P<0.001). The Co pigs had a larger percentage of cells positive for CD14 on d1 in April (P<0.05) and in both replications Co pigs had a larger percentage of CD14 positive cells on d 14 (P<0.05). On d 3 in January, the percentage of cells positive for CD18 in La pigs were larger (P<0.05). This study indicates that extended transport without lairage alters immune functions which may cause greater susceptibility to pathogens. Partial funding of this experiment was provided by the National Pork Board.