Histološke odlike mukoze želuca svinja u različitim uslovima uzgoja

Abstract

Bakterije koje kolonizuju želudac (Gastrospirillum spp. i Helicobacter spp.) su izolovane kod čoveka i nekoliko animalnih vrsta, uključujući i svinje. Gastritis je rezultat prirodne ili eksperimentalno izazvane infekcije sa H. pylori kod čoveka i konvencionalnih prasića. Kod obe vrste (čovek i svinja), infekcija sa H. pylori pokreće inflamatorni odgovor organizma, međutim postoje razlike u ćelijskoj populaciji u inflamatornom infiltratu. Cilj istraživanja ove disertaciji je identifikacija bakterije Helicobacter spp., različite morfologije (Helicobacter-like organisms and Gastrospirillum-like organisms), kao i patohistološki pregled i evaluacija gastritisa svinja uzgajanih na intenzivni i ekstenzivni način. Uzeti su uzorci mukoze pars oesophagea, fundusa i pilorusa. Za identifikaciju bakterije Helicobacter spp. korišćene su dve metode bojenja: Loefflermethylene blue i modifikovana Giemsa. Za histološko ispitivanje, uzorci su obojeni i hematoksilin eozinom (H&E). Stepen gastritisa je određen prema Sidnejskom sistemu za klasifikaciju gastritisa. U humanoj a i u veterinarskoj patologiji, dobro je poznata činjenica o različitoj patogenosti različitih bakterija Helicobacter vrsta. Helicobacter bakterije izolovane iz želuca svinja pripadaju različitim vrstama ovog roda i međusobno se bitno razlikuju kako po patogenosti, tako i po virulentnosti. Tako na primer, Helicobacter–like bakterije koje su okarakterisane kao visoko patogene, mogu izazvati ulceracije ezofagealnog ili glandularnog dela želuca, gastritis ozbiljnog stepena i formiranje limfoidnih folikula. Rezultati našeg istraživanja pokazuju da je stepen gastritisa veći u piloričnoj mukozi HLO-pozitivnih svinja u poređenju sa vrednostima GLO-pozitivnih svinja. Nije postojala pozitivna korelacija između infekcije bakterijama GLO morfologije i ulceracija. Za razliku od perzistentnih infekcija sa H. pylori kod ljudi kod kojih je teška glandularna atrofija udružena sa intestinalnom metaplazijom veoma česta, kod ispitivanih svinja iz intenzivnog i ekstenzivnog načina uzgoja nisu potvrđeni slučajevi atrofičnog gastritisa i intestinalne metaplazije. Konvencionalne svinje mogu poslužiti kao animalni model infekcije sa H. pylori jer su svinje u funkcionalnom smislu monogastrične životinje po anatomskim i fiziološkim karakteristikama, vrlo slične čoveku. Takođe, patogeneza infekcije je veoma slična kao kod čoveka. Navedene činjenice podržavaju mogućnost upotrebe ovog modela u daljem istraživanju patogeneze nastanka Helicobacter spp. gastritisa. Rezultati ovog istraživanja pružaju dodatni dokaz da HLO mogu biti faktor koji igra krucijalnu ulogu u patogenezi gastritisa kod svinja. Datum

Bacteria that colonize the stomach (Helicobacter spp. and Gastrospirillum spp.) are isolated from humans and several animal species, including pigs. Gastritis is the result of a natural or experimental induced infection with H. pylori in humans and conventionally pigs. In both, humans and pigs, the infection with H. pylori elicited inflammatory response, but there are differences between populations of inflammatory cells. The aims of this dissertation are to identify spp. with two different morphology (Helicobacter-like organisms and Gastrospirillumlike organisms), as well as histolopathological examination and evaluation of gastritis score of gastric mucosa of pigs in intensive and extensive production. Biopsy samples were taken from the pars oesophagea, fundic and pyloric mucosa. For identification of Helicobacter species morphology we used two stain methods: Loeffler-methylene blue and modified Giemsa. All tissue sections were stained with hematoxylin and eosin (H&E) for histopathological evaluation. The severity of gastritis was scored to the Sydney System for the classification of gastritis. In human as well as in veterinary pathology, the fact of the different pathogenicity of various Helicobacter species is well known. The Helicobacter spp. isolated from stomach mucosa of pigs which belong to different genus, differ significantly in both, pathogenicity and virulence. Helicobacter pylori-like bacteria characterised as high pathogenic, has been associated with ulceration of the oesophageal or glandular portion of the stomach, severe gastritis and formation of lymphoid follicles. On the contrast, infection with Helicobacter heilmannii, which has been shown to have low pathogenicity was accompanied by only mild gastritis and no ulceration. The results of current study suggested that the average gastritis score was higher in HLO-positive pyloric mucosa, compared with the GLO-positive pyloric mucosa. There was signifficance between HLO-positive and HLO-negative pyloric mucosa in both, intensive and extensive production. There was no correlation between GLO-positive mucosa and ulceration. In contrast to persistent H. pylori infection in humans in which severe glandular atrophy associated with intestinal metaplasia is very common, in examined pigs from intensive and extensive breeding, no samples exhibited histological features characteristic for atrophic gastritis and intestinal metaplasia have been confirmed in pigs of both production systems. The conventional piglets as an animal model of the human H. pylori infection offers advantages of a functional monogastric animal with gastric anatomic and physiologic characteristics similar to those of humans. Moreover, the infection and pathogenesis is similar to that in humans. These facts support the usefulness of this model in further research on the pathogenic mechanisms of Helicobacter spp. associated gastritis. Our findings provide further evidence that HLO can be one of the factors that playing a crucial role in the pathogenesis of gastritis in pigs. Accepted