Consecutive pathological and immunological alterations during experimentally induced swine dysentery – A study performed by repeated endoscopy and biopsy samplings through an intestinal cannula

Abstract

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.

Serum amyloid A and haptoglobin concentrations in serum and peritoneal fluid of healthy horses and horses with acute abdominal pain

“…SAA concentration in PF did not exceed concentrations in plasma. This was unexpected since SAA production by peritoneal and intestinal cells has been shown in healthy equine intestines and was found to be increased as a response to local inflammation in mice, pigs, and people…”

Swine Dysentery

“…25 Systemically, there is a significant increase in circulating neutrophils and monocytes during SD, 65 with an increase in the acute-phase proteins serum amyloid A (SAA) and haptoglobin at the onset of clinical disease 57 ; however, a febrile response is not typically observed. 58,65 The proinflammatory cytokine interleukin (IL) 1b increases significantly on the first day of clinical disease, 73 and SAA levels remain elevated more than 6 times the baseline during the first 3 days of mucohemorrhagic diarrhea. 65 During the dysentery period, there is a decrease in serum concentrations of some nonessential gluconeogenic amino acids including alanine, glutamine, and tyrosine.…”

A Simulation‐based Study Comparing A Traditional and An Alternative Design for Studies of Experimentally Induced Intestinal Diseases in Pigs

“…Med. A 54, 455-457 (2007) Ó 2007 The Authors Journal compilation Ó 2007 Blackwell Verlag ISSN 0931-184X outcome of interest was assumed to be crypt length (Jacobson et al, 2006) and the effects of possible treatments on crypt length was ignored for reason of simplicity, i.e. the data were generated as if all animals underwent no (or the same) treatment, because the purpose was to compare the designs and not to evaluate potential treatment effects.…”

“…The parameters of the simulation were chosen so that the generated data were as similar as possible to observed intestinal crypt length data from an inoculation experiment on pigs (Jacobson et al, 2006).…”

“…Additionally, data derived from an observational study on seven pigs (Jacobson et al, 2006) were analysed with the generalized linear mixed model approach to validate the simulation.…”