The aim of this study was to examine changes in the systemic immune response during the incubation period and following the onset of clinical swine dysentery, including the recovery period. Ten healthy conventional pigs were inoculated with Brachyspira hyodysenteriae. Blood was sampled at pre-inoculation, at days 4 and 14 post-inoculation, during the first 4 days with clinical signs of dysentery and at days 1, 3, 7, 11 and 15 of the recovery period. Eight pigs developed haemorrhagic diarrhoea. Flow-cytometric analyses of lymphocyte subpopulations showed that all animals, including the two that remained healthy, had an increase in CD8a + CD4 " cells and cd T cells at days 4 and 14 post-inoculation. In addition, an increase in CD4 + CD8a + cells and CD8a + CD8b + cells was observed at days 4 and 14 post-inoculation in animals that developed dysentery. During clinical signs of dysentery, the acute-phase protein serum amyloid A was increased. There was a two-to threefold increase in both neutrophils and monocytes during signs of dysentery and at the beginning of the recovery period. The numbers of CD8a + CD8b " CD4 " , CD45RA " lymphocytes also increased during the dysentery period. Circulating CD21 + cells and CD21 + CD45RA " cells decreased at the end of the incubation period, during signs of dysentery and at the beginning of the recovery period. The dysentery-affected animals developed antibodies to B. hyodysenteriae-specific antigens (~16 kDa and~30 kDa) from the first day of recovery, and cd T cells showed an increase during the recovery period. In comparison with pre-inoculation, increased numbers of monocytes, neutrophils, CD8a + CD8b " CD4 " lymphocytes and CD45RA " lymphocytes were observed during clinical dysentery. Increased numbers of neutrophils, cd T cells and specific antibodies were seen during the recovery period. Taylor and Alexander (1971) showed that swine dysentery is caused by the Gram-negative spirochaete Brachyspira hyodysenteriae. The main clinical signs are severe mucohaemorrhagic diarrhoea and a reduced general appearance. The typical manifestations in the large intestine are excessive mucus production, haemorrhage and tissue necrosis. Due to the increased antimicrobial resistance of B. hyodysenteriae to the few antibiotic treatments available (Lobova et al., 2004), a better knowledge of the host responses during infection is essential for development of prophylactic measures. In pigs, macrophages and neutrophils are found in colonic lesions at later stages of swine dysentery, but the role of these cells is still unclear (Albassam et al., 1985). Experimental infections with B. hyodysenteriae in mice demonstrate that neutrophils are of great importance in mediating the severe oedema and structural lesions that occur in the intestine during the infection , and may thus be part of the pathogenesis. However, the commensal intestinal flora has also been shown to be necessary for the development of the disease (Whipp et al., 1979; Neef et al., 1994). Among lymphocyte subsets, CD8 + cells appear ...

The development of intestinal lesions after inoculation with Brachyspira hyodysenteriae was followed by repeated endoscopy and biopsy sampling through a caecal cannula. Seven eight-week-old pigs were cannulated and inoculated, two were cannulated but not inoculated, and two pigs were inoculated but not cannulated. Endoscopy, biopsy, and blood sampling to determine SAA (serum amyloid A), haptoglobin, cortisol, and WBC counts were performed at scheduled time-points. At the third day of disease, endoscopy showed a hyperaemic, perturbed mucosa and excessive amount of mucus. Histologically, crypt hyperplasia, depletion of goblet cell mucus, and erosions were noted. Simultaneously, elevated acute phase proteins and circulating monocytes, and decreased number of intraepithelial CD3(+) cells were observed. After five days the pigs recovered. Intestinal lesions were demarcated and interspersed among apparently normal mucosa and blood parameters returned to initial values. Endoscopy through an intestinal cannula made it possible to follow the development of intestinal alterations in vivo and describe the sequential events during the course of swine dysentery. The number of animals used in a study could thus be minimised and the precision of the experiment increased.

The RN- mutation was associated with high MG stores in skeletal muscle that did not influence exercise performance. The RN- mutation did not impair glycogenolysis during exercise but may induce faster resynthesis of MG after exercise.

Background: Multiplex flow cytometry is in widespread use for detection of cytokines in human samples. However, no report on the measurement of porcine cytokines using this method has previously been published. We report on the detection of the porcine proinflammatory cytokines TNF‐α, IL‐8, and IL‐1β by the xMap‐assay for multiplex flow cytometry. Methods: Commercially available antibodies to porcine cytokines were used as capture antibodies by attaching them to goat anti‐mouse IgG coated microspheres with different fluorescent signatures. By the use of biotinylated detection antibodies and SAv‐PE the amount of cytokines bound to the spheres were measured. Experiments were performed to determine the limits of detection and the amount of crossreactivity in buffer, serum, and plasma, using spiking with recombinant porcine cytokines. Results: The limit of detection ranged from 0.18 to 12 ng/ml. Generally, the detection limit was higher in serum and plasma, than in buffer. No crossreactivity between reagents was found. Conclusions: Porcine proinflammatory cytokines can be detected utilizing this method with satisfactory detection limits, and no crossreaction between the reagents involved. © 2006 International Society for Analytical Cytology

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