Wattrang, Eva
- Department of Veterinary Microbiology, Swedish University of Agricultural Sciences
The growth rate and several immune parameters were recorded to monitor the performance, health and immune status of 40 piglets in a conventional farrow to finish herd. In addition, effects of wearing on immune parameters were studied under minimal influence of infections in 20 specific pathogen free (SPF) pigs. The growth rate of the conventionally reared pigs decreased after weaning and after allocation of pigs to new premises. Around weaning a considerable number of pigs displayed interferon-alpha (IFN-alpha) in serum, indicating the spread of vital infections. Bacterial infections were indicated by elevated numbers of circulating neutrophilic granulocytes during the weaning period. Functional in vitro tests of peripheral blood mononuclear cells (PBMC) revealed that the Concanavalin A (CON A) induced proliferation decreased both after wearing and after transfer of the conventionally reared pigs to the finishing unit. The decreased proliferation observed after weaning was accompanied by decreased interleukin-2 (IL-2) production in response to the mitogen. A reduced IL-2 producing capacity after weaning was confined with PBMC obtained from the SPF pigs. Flow cytometric analyses of these cells showed that the proportion of PBMC expressing IL-2 receptors (IL-2R(+)) was decreased 3 and 6 days after weaning when cultured in the absence of mitogen while the proportion of IL-2R(+) cells was unaltered in Con A simulated cultures. Thus indications of reduced immune function coincided in time with signs of infections, especially around weaning.
Journal of veterinary medicine. Series B
1998, volume: 45, number: 1, pages: 7-17
Publisher: WILEY-BLACKWELL
Clinical Science
https://res.slu.se/id/publ/106615