Učinak levamisola na brojnost crijevnih vrčastih stanica odbijene prasadi pokusno cijepljene protiv kolibaciloze

Postweaning colibacillosis (PWC) is an etiologically complex disease commonly induced by porcine F4ac+ enterotoxigenic Escherichia coli (ETEC) for which no effective vaccine is available. The objective of this study was to determine the nonspecific immunomodulatory effect of levamisole in combination with specific intragastric immunization of weaned pigs with a candidate F4ac+ non-ETEC oral vaccine on the population of intestinal goblet cells (GC). The pigs were immunized with F4ac+ non-ETEC strain, in combination with or without levamisole. Seven days after immunization the pigs were challenged with F4ac+ ETEC strain and 14 days following immunization they were euthanatized for sampling of specimens of the small intestine for immunohistochemistry and morphometric analyses. Samples of the ileum were tested for the presence of acidic and neutral carbohydrates, components of mucus produced and secreted by the intestinal goblet cells (GC). The volume density (VV) of the PAS+ and AB+/PAS+ GC was determined using the stereological point-counting method. The Vv of the ileal PAS+ GC was lowest (0.130 ± 0.075 mm3) in the pigs that were immunized with the vaccine candidate F4ac+ non-ETEC strain. Interestingly, AB+/PAS+ GC Vv were found to be highest (0.262 ± 0.091 mm3) in this group of pigs. The Vv of PAS+ GC was the largest (0.201 ± 0.064 mm3) in the negative control group of pigs. Pigs from the levamisole pretreated group were shown to have the lowest Vv (0.166 ± 0.051 mm3) of AB+/PAS+ GC. According to the data presented, there was no significant influence of nonspecific/specific immunization on the nonimmune defence mechanism of the intestinal mucosa, as measured by GC Vv in weaned pigs. Hence, it is likely that the production of mucus was not affected and that nonspecific protection of porcine intestines provided by mucus layer was not compromised following peroral immunization against PWC. Also, presumably the anti-inflammatory effect of levamisole was observed as the population of ileal mast cells was not considerably affected by non-specific/specific immunization and challenge infection.Kolibaciloza odbijene prasadi (KOP) etiološki je složena bolest, najčešće izazvana svinjskim F4ac+ enterotoksigenim sojevima bakterije Escherichia coli (ETEC), za koju nema djelotvorne vakcine. Namjera ovoga rada bila je da se utvrdi imunomodulacijski učinak levamisola, u kombinaciji sa specifičnom intragastričnom imunizacijom odbijene prasadi pokusnim vakcinalnim F4ac+ ne-ETEC sojem, na populaciju crijevnih vrčastih stanica (VS). Prasad je bila imunizirana F4ac+ ne-ETEC sojem u kombinaciji s levamisolom ili bez njega, sedam dana nakon toga bila je izazivački inficirana F4ac+ ETEC sojem, a 14 dana nakon imunizacije bila je usmrćena radi uzimanja uzoraka crijeva za imunohistokemijske i morfometrijske analize. Uzorci ileuma testirani su na prisutnost kiselih i neutralnih ugljikohidrata, sastavnica sluzi koju proizvode i izlučuju VS. Volumna gustoća (Vg) VS koje se boje kombinacijom alcijanskoga modrila (AM) i periodičnoga kiseloga Schiffovoga (PKS) reagensa određivana je pomoću stereologijske metode brojanja točaka. Vg ilealnih PKS+ VS bila je najniža (0,130 ± 0,075 mm3) u prasadi imunizirane pokusnim vakcinalnim F4ac+ ne-ETEC sojem. Međutim, zanimljivo je da je utvrđena najveća Vg AM+/PKS+ VS (0,262 ± 0,091 mm3) u prasadi iz te skupine. U prasadi iz negativne kontrolne skupine utvrđena je najveća Vg PKS+ VS (0,201 ± 0,064 mm3), dok je prasad iz skupine obrađene levamisolom i vakcinalnim ne-ETEC sojem imala najnižu Vv ukupnih (AM+/PKS+) VS (0,159 ± 0,023 mm3). Primjereno dobivenim rezultatima, nije utvrđen značajan utjecaj nespecifične/specifične imunizacije na neimunosne obrambene mehanizme crijevne sluznice vrednovane temeljem Vg i distribucije VS u odbijene prasadi. Stoga je vrlo vjerojatno da proizvodnja sluzi nije umanjena i da nespecifična zaštita crijeva prasadi slojem sluzi ne bi bila slabija nakon peroralne imunizacije protiv KOP. Također je zapažen potencijalni protuupalni učinak levamisola s obzirom na činjenicu da populacija ilealnih mastocita nije bila znatnije stimulirana nespecifičnom/specifičnom imunizacijom i izazivačkom infekcijom

Effect of levamisole on the number of intestinal goblet cells in weaned pigs experimentally vaccinated against colibacillosis

VALPOTIĆ: Effect of levamisole on the number of intestinal goblet cells in weaned pigs experimentally vaccinated against colibacillosis. Vet. arhiv 79, 543-553, 2009. Postweaning colibacillosis (PWC) is an etiologically complex disease commonly induced by porcine F4ac + enterotoxigenic Escherichia coli (ETEC) for which no effective vaccine is available. The objective of this study was to determine the nonspecific immunomodulatory effect of levamisole in combination with specific intragastric immunization of weaned pigs with a candidate F4ac + non-ETEC oral vaccine on the population of intestinal goblet cells (GC). The pigs were immunized with F4ac + non-ETEC strain, in combination with or without levamisole. Seven days after immunization the pigs were challenged with F4ac + ETEC strain and 14 days following immunization they were euthanatized for sampling of specimens of the small intestine for immunohistochemistry and morphometric analyses. Samples of the ileum were tested for the presence of acidic and neutral carbohydrates, components of mucus produced and secreted by the intestinal goblet cells (GC). The volume density (V) of the PAS V + and AB +/PAS+ GC was determined using the stereological point-counting method. The Vv of the ileal PAS + GC was lowest (0.130 ± 0.075 mm3) in the pigs that were immunized wit

Flax-seed oil and Lactobacillus plantarum supplementation modulate TLR and NF-κB gene expression in enterotoxigenic Escherichia coli challenged gnotobiotic pigs

The present study analyses the effect of flax-seed oil rich in n-3 polyunsaturated fatty acids (PUFAs), the probiotic strain Lactobacillus plantarum — Biocenol™ LP96 and their combination on the expression level of selected Toll-like receptor (TLR) genes (TLR2, TLR4, TLR5, TLR9) and their downstream molecules (myeloid differentiation factor 88, MyD88; nuclear factor-κB, NF-κB) in the jejunum of gnotobiotic pigs challenged with enterotoxigenic Escherichia coli (ETEC). The results show that both immunomodulators are able to modulate the RNA level of at least one of the target molecules and thus regulate pathogeninduced inflammation. We confirmed that not only probiotic lactobacilli or flaxseed oil alone but also their synergistic action has great potential in the prevention and treatment of porcine colibacillosis. The results give an insight into one of the possible mechanisms by which natural agents, such as probiotic lactobacilli and flax-seed oil, exert their immunoregulatory properties during pathogen-induced inflammation

Comparison of antimicrobial resistance phenotypes and genotypes in enterotoxigenic Escherichia coli isolated from Australian and Vietnamese pigs

This study aimed to compare the antibiogram phenotype and carriage of antimicrobial resistance genes (ARGs) of 97 porcine multidrug-resistant (MDR) enterotoxigenic Escherichia coli (ETEC) isolates obtained from Vietnam and 117 porcine MDR-ETEC obtained from Australia, two countries with different antimicrobial regulation systems. An antimicrobial resistance index (ARI) was calculated to quantify their potential significance to public health. Both Vietnamese and Australian isolates had moderate to high levels of resistance to commonly used antibiotics (ampicillin, tetracycline and sulphonamides). None of the Australian isolates were resistant to fluoroquinolones or third-generation cephalosporins and none possessed associated plasmid-mediated ARGs. However, 23.1% of Australian isolates were resistant to gentamicin owing to ARGs associated with apramycin or neomycin resistance [e.g. aac(3)-IV] that impart cross-resistance to gentamicin. Whilst Vietnamese isolates carried aminoglycoside ARGs, 44.4% of commercial pig isolates were resistant to gentamicin in comparison with 0% of village pig isolates. The plasmid-mediated fluoroquinolone ARG qnrB was commonly detected in Vietnamese isolates (52.3% commercial, 44.1% village), but phenotypic resistance was low (3.2% and 11.8%, respectively). The mean ARI for Vietnamese isolates (26.0) was significantly different (P < 0.001) from the mean ARI for Australian isolates (19.8), primarily reflecting fluoroquinolone resistance in the former collection. This comparison suggests the effectiveness of regulations that slow the dissemination of 'critical' resistance by restricting the availability of important classes of antimicrobials

Mycoplasma suis infection in suckling pigs on a Belgian farm

Mycoplasma suis (formerly known as Eperythrozoon suis) is an epicellular bacterium that affects porcine red blood cells. M. suis infections occur worldwide and are associated with weakness and anemia in suckling and weaned pigs, and reproductive disorders in sows. The present field report describes the detection of M. suis in anemic piglets originating from a Belgian farrow-to-finish herd. The herd was experiencing increased piglet mortality (16%) in the farrowing unit and had a high percentage of repeat breeders (22%). A control program using antimicrobials and hygienic and sanitary measures significantly decreased the number of clinically anemic piglets and the mortality rate in the farrowing unit. However, it did not have any significant influence on the reproductive failure of the farm. The lack of a significant effect on reproductive failure was probably due to the circulation of porcine reproductive and respiratory syndrome virus (PRRSV) on the farm

Enteric diseases in pigs from weaning to slaughter

The general aim of this thesis was to study enteric diseases in growing pigs, with special reference to diseases caused by Brachyspira hyodysenteriae and Lawsonia intracellularis. The occurrence of enteric diseases in “growers” is a problem of increasing importance in Sweden and an understanding of the mechanisms by which the microorganisms causes enteric diseases is essential to develop good prophylactic measures. The most important microorganisms involved in enteric diseases in grower pigs were identified as Lawsonia intracellularis and Brachyspira pilosicoli, as determined by necropsy, microbiological and histopathological examinations performed on representative growing pigs from good and poor performing herds. Diagnostic methods based on polymerase chain reaction for L. intracellularis in tissue or faecal samples were established and the results related to those obtained by necropsy and serology. An internal control, a mimic, was constructed to demonstrate inhibition of the PCR reactions and to evaluate different preparation methods. The methods for the demonstration of L. intracellularis in tissue samples were sensitive and specific, and the bacteria were reliably identified in faeces from pigs with overt disease. A number of factors interacting in the clinical expression of swine dysentery were evaluated. In this work, group-housing of pigs and the addition of 50% soybean meal in feed was shown to predispose for infection. A model was developed that enabled the sequential monitoring of disease in single animals by repeated endoscopy and biopsy sampling through a caecal cannula. This reduced the number of experimental animals required and increased the accuracy of the study. The general condition of the animal was not affected. The model was used to study the development of experimentally induced swine dysentery and the sequential development of lesions was characterised by histopathology and immunohistochemistry. An increase in the acute phase proteins serum amyloid A and haptoglobin and in monocytes was seen when haemorrhagic dysentery occurred

Kejadian Kolibasilosis pada Anak Babi

A study was conducted to know the incidence of colibacillosis in piglets based of age factors. A total 2005 samples of fecal swab isolated from a piglets in farm of Badung, Tabanan, Gianyar and Denpasar regency, district of Bali. Fecal swab samples were collected from feces and continued by isolation and identification Escherichia coli. This study showed that, the incidence of colibacillosis in piglets were 846 (42%) and the high risk factors occurrence of colibacillosis for young piglets between 0-2 weeks (62%)

Efficacy of a reduced protein diet on clinical expression of post-weaning diarrhoea and life-time performance after experimental challenge with an enterotoxigenic strain of Escherichia coli

Previous experiments have shown that feeding a reduced protein diet within the first 2 weeks post-weaning reduces gastrointestinal protein fermentation and clinical expression of post-weaning diarrhoea (PWD). However, growth of young pigs receiving a reduced protein diet without crystalline essential amino acids (CEAA) supplementation is depressed after weaning. It has been argued that the short-term performance reduction caused by feeding a reduced protein diet would be compensated and the lifetime performance of pigs would not be affected. An experiment was therefore conducted to examine PWD and lifetime growth of pigs after feeding a reduced protein diet without and with CEAA supplementation for 2 weeks after weaning. Two hundred individually housed pigs weaned at 21 d of age (Large White×Landrace, castrate:female ratio of 1:1, mean±SEM body weight of 5.5±0.05kg) were stratified to one of four dietary treatments (n=50): High protein+antimicrobial compound diet (HP+AMC, 230g crude protein (CP) with 2.5g lincospectin and 3g zinc oxide per kg feed), High protein diet (HP, 230gCP/kg), Reduced protein+amino acid supplemented diet (RP+AA, 185gCP/kg with added CEAA up to HP level), and Reduced protein diet (RP, 185g CP/kg without CEAA supplementation). Pigs were fed the experimental diet for 2 weeks and then all pigs were fed the same series of commercial diets until slaughter. All pigs were experimentally infected with an enterotoxigenic strain of E. coli (6 and 10mL of 1.9×109cfu/mL, serotype O149:K91:K88) at 72, and 96h after weaning. Infection increased plasma haptoglobin levels (P0.05). Carcass characteristics were not affected (P>0.05) by the treatments. The results indicate that although feeding a RP diet without CEAA supplementation decreased performance after weaning, it did not influence lifetime performance or carcass characteristics and reduced the clinical expression of PWD