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Study on the Reassortment and the Presence of G genotypes of Bovine Group A Rotaviruses in the Human Rotaviruses in Tehran
2020
Madadgar, Omid | Hosseini, Seyed Masoud | Nazaktabar, Ahmad | Barin, Abbas | Jahangiri, Faeze | Vahedi, Ahmad
BACKGROUND: Rotavirus Group A is one of the most important causes of gastroenteritis as it is isolated from 30 to 50% of infant diarrhea from humans and other animals. G genotype of the virus is determined by gene sequence of a surface protein of the virus (VP7), one of the most important factors in inducing immunity against the virus which acts very specific to each genotype. OBJECTIVES: In the present study the presence of common bovine rotavirus genotypes A was examined in human rotavirus population. METHODS: A total of 100 stool samples from children under 2 years of age in Tehran and Varamin were collected and to track the presence of rotavirus A, were evaluated using ELISA method. Positive samples were isolated and cultured on the MA-104 cell line after several passages. The positive samples (49 samples) were determined to be the G type using semi-nested RT-PCR and primers specific for bovine common genotype. RESULTS: From 100 samples, 49 were positive in ELISA. Eight samples in the first semi nested RT-PCR showed the desired rotavirus bands and in the second round, the results were positive for the presence of bovine VP7 in two samples taken from Varamin, in one sample, G6, and in another sample, two genotypes of VP7, G6 and G8 were detected, indicating infection with at least two strains of human rotavirus reassortant. Six of the ELISA selected positive samples that were taken to the cell line MA104, showed effects of cell damage (CPE) after 4-5 consecutive passages, demonstrating proliferation of the rotaviruses of this study and so, their viability was confirmed. CONCLUSIONS: The results of this study indicate reassortment between bovine and human rotaviruses and show that in case of occurrence of bovine and human rotavirus infection and the emergence of new human type, due to reassortment strain differences in protein immunogen it is possible to overcome due to lack of maternal immunity in the human population and low efficiency of current vaccines and, ultimately, epidemic and considerable losses may occur. Hence, more research is warranted.
Afficher plus [+] Moins [-]Characterisation of porcine enteropathogenic Escherichia coli isolated in northeastern India
2020
Kylla, Hosterson | Dutta, Tapan Kumar | Roychoudhury, Parimal | Subudhi, Prasant Kumar | Lalhruaipuii, | Lalsiamthara, Jonathan | Mandakini, Rajkumari
Enteropathogenic Escherichia coli (EPEC) is one of the main pathotypes causing gastroenteritis, particularly in young immunocompromised hosts. The study reports the prevalence, characterisation, and molecular epidemiology of EPEC from piglets in northeastern India. A total of 457 faecal samples were collected, from which 1,286 E. coli strains were isolated and screened by PCR. The resultant EPEC strains were serotyped and phenotypically characterised for resistance against 15 antimicrobials. Also, the phylogenetic sequence was analysed for 11 selected strains. A total of 42 strains (3.26%) belonged to atypical EPEC, of which, 15 (35.71%, and 2.29% of the 654 strains from this farm type) were isolated from organised and 27 (64.29%, and 4.27% of the 632 strains from this farm type) from unorganised farms; further, 5 (11.90% of the EPEC strains and 1.51% of the 330 strains from this breed) were isolated from the indigenous breeds and 37 (88.10%, and 3.87% of the 956 strains from this breed) from crossbred piglets. Serogroups O111 (11.9%) and O118 (7.14%) were the most prevalent of the 10 present. Sequence analysis of a length of the eaeA gene of 11 isolates of the region showed them to have 100% homology with each other and their identity ranged from 99.4% to 99.7% with GenBank reference sequences. All the EPEC isolates were multi-drug resistant, showing the highest resistance to amoxicillin (80.9%) and cephalexin (76.19%). The study highlighted the association of EPEC with piglet’s diarrhoea in northeastern India. EPEC isolates belonged to many serotypes and phenotypically all were multi-drug resistant with close genetic homology.
Afficher plus [+] Moins [-]Correlation between endoscopic and histopathological findings in dogs with chronic gastritis
2017
Çolakoğlu, Ekrem Ç | Börkü, Kazım | Haydardedeoğlu, Ali E. | Alihosseini, Hadi | Şenel, Oytun O. | Yumuşak, Nihat | Özen, Doğukan | Baş, Bülent | Uğurlu, Levent
Introduction: Chronic gastritis is a common diagnosis in dogs with signs of chronic vomiting. However, there is no data concerning endoscopic and histopathological agreement in dogs with chronic gastritis. Thus, a question should be raised whether taking gastroduodenal biopsies in dogs with chronic gastritis is necessary or not. Consequently, the purpose of the study was to compare the endoscopic and histopathological agreement in dogs with chronic gastritis. Material and Methods: A total of 22 non-pregnant client-owned dogs with the signs of chronic gastritis were enrolled in this prospective study. Procedures including clinical examination, blood analysis, and diagnostic imaging were performed before anaesthesia. Biopsies obtained from gastroduodenal sites were histopathologically evaluated. A total of 110 gastroduodenal samples were examined. Results: Sixtyeight samples had abnormal histopathology and endoscopy while 11 showed normal histopathological and endoscopic evidence. Conclusion: The obtained data demonstrated that it is not necessary to take extra gastroduodenal biopsies in dogs with evidence of endoscopic gastroduodenitis. We also believe that further prospective studies, including cost and time effectiveness and more specific comparison between endoscopic appearance and histopathology, are necessary to make final recommendations regarding the need of using both procedures for definitive diagnosis.
Afficher plus [+] Moins [-]Characterisation of Yersinia enterocolitica strains isolated from wildlife in the northwestern Italian Alps
2022
Carella, Emanuele | Romano, Angelo | Domenis, Lorenzo | Robetto, Serena | Spedicato, Raffaella | Guidetti, Cristina | Pitti, Monica | Orusa, Riccardo
Yersiniosis is a zoonosis causing gastroenteritis, diarrhoea, and occasionally reactive arthritis and septicaemia. Cases are often linked to meat consumption and the most common aetiological agent is the Gram-negative bacilliform Yersinia enterocolitica bacterium. The occurrence of Yersinia spp. among wild animals has mostly been studied in wild boar, but it has seldom been in other species. A total of 1,868 faecal samples from animals found dead or hunted were collected between 2015 and 2018 in the Valle d’Aosta region of the northwestern Italian Alps. Alpine ibex faecal samples were collected during a health monitoring program in 2018. Bacteria were isolated via PCR and confirmed as Y. enterocolitica biochemically. Strain antimicrobial susceptibility was tested by Kirby–Bauer disc diffusion, and the presence of virulence factors and antimicrobial resistance genes was investigated using whole-genome sequencing. Yersinia enterocolitica strains of biotype 1A were detected in six faecal samples from red deer (0.93%), roe deer (0.49%) and red foxes (0.7%). Strains found in beech martens (3.57%) and Alpine ibex (2.77%) belonged to biotypes 1B and 5, respectively and harboured the pYPTS01 plasmid that had only been detected in Y. pseudotuberculosis PB1/+. All the isolates were resistant to ampicillin and erythromycin. The biovar 1A strains exhibited different virulence factors and behaved like non-pathogenic commensals. The strain from an Alpine ibex also harboured the self-transmissible pYE854 plasmid that can mobilise itself and the pYPTS01 plasmid to other strains. The beech marten could be considered a sentinel animal for Y. enterocolitica. Phenotypic resistance may account for the ability of all the strains to resist β-lactams.
Afficher plus [+] Moins [-]Current status of porcine epidemic diarrhoea (PED) in European pigs
2019
Porcine epidemic diarrhoea (PED) is a highly contagious and devastating enteric disease of pigs caused by porcine epidemic diarrhoea virus (PEDV), an enveloped, single-stranded RNA virus belonging to the Alphacoronavirus genus of the Coronaviridae family. The disease is clinically similar to other forms of porcine gastroenteritis. Pigs are the only known host of the disease, and the occurrence of PED in wild boars is unknown. The virus causes acute diarrhoea, vomiting, dehydration, and high mortality in suckling piglets reaching 100%. Heavy economic losses in the pig-farming industry were sustained in the USA between 2013 and 2015 when PEDV spread very quickly and resulted in epidemics. The loss in the US pig industry has been estimated at almost seven million pigs. The purpose of this review is a description of the current status of porcine epidemic diarrhoea in European pigs and the risk presented by the introduction of PEDV to Poland in comparison to the epidemics in the USA.
Afficher plus [+] Moins [-]Assessment of the Degree of Dehydration in Dogs Based on Biochemical Parameters Using Ordinal Logistic Regression
2023
Ahmed Fathy | Ahmed E. Mahmoud | Asmaa O. Ali | Nahla M. Mouhamed | Khalid M. Ibrahim | Dina A. Abdelkhalek
This experimental study was carried out in the faculty of veterinary medicine, at Suez Canal University, Ismailia, Egypt. A total of 40 dogs were categorized based on the severity of dehydration into three categories (mild, moderate, and severe) and a fourth group for dogs without dehydration. Many biochemical parameters were utilized to evaluate dehydration, including blood electrolytes (Na, K, CL, Ca, Mg, and Ph), liver enzymes (ALT and AST), kidney function parameters (urea, creatinine, and uric acid), and lactate. The most prevalent clinical manifestations of gastroenteritis in dogs were vomiting, followed by profuse watery yellowish to bloody diarrhea, anorexia, and mild, moderate, and severe degrees of dehydration manifested by STT retardation. Four OLR models ranging from univariable to multivariable logistic regression were developed. Lactate, AST, creatinine, urea, and uric acid were recorded as positive predictors for the severity of dehydration; however, only lactate, AST, and uric acid were recorded as positive significant (p<0.05) predictors for the degree of dehydration. Na, K, Cl, Ca, Mg, Ph, and ALT were all negative predictors of dehydration level. Na and K were significant (P0.05) negative predictors of the degree of dehydration, whereas the remaining variables were not substantially related to the degree of dehydration. It was observed that biochemical markers are good indicators of dehydration; including these factors in the OLR model will help in differentiating between different degrees of dehydration.
Afficher plus [+] Moins [-]Comparison of the expression, activity, and fecal concentration of intestinal alkaline phosphatase between healthy dogs and dogs with chronic enteropathy
2016
Ide, Kaori | Kato, Kazuki | Sawa, Yuki | Hayashi, Akiko | Takizawa, Rei | Nishifuji, Koji
OBJECTIVE To compare expression, activity, and fecal concentration of intestinal alkaline phosphatase (IAP) between healthy dogs and dogs with chronic enteropathy (CE). ANIMALS 9 healthy university-owned Beagles and 109 healthy client-owned dogs (controls) and 28 dogs with CE (cases). PROCEDURES Cases were defined as dogs with persistent (> 3 weeks) gastrointestinal signs that failed to respond to antimicrobials and anti-inflammatory doses of prednisolone or dietary trials, did not have mechanical gastrointestinal abnormalities as determined by abdominal radiography and ultrasonography, and had a diagnosis of lymphoplasmacytic enteritis or eosinophilic gastroenteritis on histologic examination of biopsy specimens. Duodenal and colonic mucosa biopsy specimens were obtained from the 9 university-owned Beagles and all cases for histologic examination and determination of IAP expression (by real-time quantitative PCR assay) and activity (by enzyme histochemical analysis). Fecal samples were obtained from all dogs for determination of fecal IAP concentration by a quantitative enzyme reaction assay. RESULTS For dogs evaluated, IAP expression and activity were localized at the luminal side of epithelial cells in the mucosa and intestinal crypts, although both were greater in the duodenum than in the colon. Active IAP was detected in the feces of all dogs. Intestinal alkaline phosphatase expression and activity were lower for cases than for controls, and fecal IAP concentration for dogs with moderate and severe CE was lower than that for dogs with mild CE. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that dogs with CE had impaired IAP expression and activity. Additional research is necessary to elucidate the role of IAP in the pathogenesis of CE.
Afficher plus [+] Moins [-]Lactogenic immunity and milk antibody isotypes to transmissible gastroenteritis virus in sows exposed to porcine respiratory coronavirus during pregnancy
1995
Lanza, I. | Shoup, D.I. | Saif, L.J.
Passive protection provided by sows inoculated with the virulent Miller strain of transmissible gastroenteritis virus (TGEV), or the ISU-1 strain of porcine respiratory coronavirus (PRCV), or both was evaluated in nursing pigs challenge exposed with virulent TGEV. Four sows (group B) were inoculated with PRCV oronasally twice at 4 and 2 weeks before parturition; 1 sow (group C) was inoculated similarly, but in 2 subsequent pregnancies; and 2 sows (group D) were oronasally primed with PRCV at 4 weeks before parturition, and 2 weeks later were administered a booster inoculation of virulent TGEV. Two additional sows (group E) remained uninoculated and served as seronegative controls, and 1 sow (group A) that had been naturally infected with TGEV served as a seropositive control. The degree of passive immunity transferred by these sows to their litters was assessed by challenge exposing the pigs of sows in groups BE (only the second litter of group C) with virulent TGEV at 3 to 5 days of age. After challenge exposure, clinical signs of infection and mortality were noted and fecal and nasal shedding of virus was assessed by ELISA. The IgA, IgG, and IgM antibody titers to TGEV were quantified in colostrum and milk of the sows by use of an isotype-specific monoclonal antibody-capture ELISA, using biotinylated monoclonal antibodies against each porcine isotype as detecting reagents. A plaque-reduction assay was used to quantify neutralizing antibody titers in serum, colostrum, milk, and fractionated whey (IgG and IgA/IgM). In the sow naturally infected with TGEV (group A), there was a pronounced decrease in IgG antibody titers to TGEV in the transition from colostrum to milk, and IgA TGEV antibodies became predominant, with high titers maintained throughout lactation. The 4 group-B sows partially protected their pigs after TGEV challenge exposure; mean mortality was 67%, compared with 100% in pigs suckling the 2 TGEV seronegative control sows (group-E litters). Although IgA TGEV antibodies were detected in colostrum and milk of group-B sows, IgG TGEV antibodies were the most abundant. The sow of group C had a marked increase in IgA TGEV antibody titers in colostrum and milk after reinoculation with PRCV during the second pregnancy, before TGEV challenge exposure of the litter. Its pigs were passively protected to a high degree after TGEV challenge exposure (27% litter mortality). The sows in group D, primed with PRCV and boosted with TGEV, provided the best passive protection after TGEV challenge exposure of their pigs. Not only litter mortality (27%) but also morbidity was reduced, compared with those factors for the other challenge exposed litters, and the sows did not become ill. In these swine, the high degree of passive protection observed could not be associated with the presence of only IgA TGEV antibodies in the milk, but high IgM TGEV antibody titers also were detected in colostrum and milk. Results of this study suggest that PRCV-inoculated sows are able to partially protect their pigs from TGEV challenge exposure and, on the basis of preliminary data, the degree of protection may increase after multiple PRCV exposures or after secondary exposure to TGEV during pregnancy. Also, an IgA respiratory tract-mammary gland link may exist as evident by the low titer of IgA TGEV antibodies in the milk of PRCV-inoculated sows, but may not be as efficient in inducing lactogenic IgA immunity as is the gastrointestinal tract-mammary gland link.
Afficher plus [+] Moins [-]Lymphocyte proliferation responses of pigs inoculated with transmissible gastroenteritis virus or porcine respiratory coronavirus
1994
Brim, T.A. | VanCott, J.L. | Lunney, J.K. | Saif, L.J.
Cell-mediated immunity was evaluated in intestinal, respiratory, and systemic lymphoid tissues of pigs exposed when 11 days old to virulent transmissible gastroenteritis virus (TGEV), attenuated TGEV, or porcine respiratory coronavirus (PRCV), 3 antigenically related porcine coronaviruses with distinct enteric and respiratory tissue tropisms. Mononuclear cells were prepared from mesenteric lymph nodes (MLN), bronchial lymph nodes (BLN), and spleens of pigs and tested for virus-specific responses by use of lymphocyte proliferation assays. Vigorous MLN and BLN proliferation responses to virulent TGEV and PRCV, respectively, at postinoculation days 8 to 24 were strongly associated with prior detection of TGEV in rectal swab samples and PRCV in nasal swab samples. Gastrointestinal disease and intestinal virus replication, assessed on the basis of rectal virus shedding, were almost exclusively found in the virulent TGEV-inoculated pigs, even though virulent TGEV and a high dose of attenuated TGEV elicited the highest proliferation responses in MLN. Pigs exposed to PRCV or attenuated TGEV did not have clinical signs of disease, and only 1 pig given a high dose of attenuated TGEV shed virus in feces. Porcine respiratory coronavirus replicated in the respiratory tract after either oronasal or aerosol inoculation of virus and induced strong BLN, but not MLN, proliferation responses. A high dose of attenuated TGEV (4 X 10(8) plaque-forming units) was more effective than a lower dose of attenuated TGEV (7 X 10(6) plaque-forming units) in eliciting significant lymphocyte proliferation in MLN and BLN. Cellular immune function, assessed on the basis of mitogen-induced proliferation of lymphocytes, was comparable for all 3 sources of lymphocytes and was not adversely affected by exposure to any of the pigs. The tissue tropism of TGEV and PRCV was associated with induction of virus-specific cell-mediated immune responses, as evidenced by substantial lymphocyte proliferation responses in MLN and BLN, mucosa-associated lymph nodes adjacent to the primary sites of virus replication. The failure of PRCV strain ISU-1 to replicate in the intestinal tract correlated with poor virus-specific cellular immune responses in MLN.
Afficher plus [+] Moins [-]Clinical evaluation of transmissible gastroenteritis virus vaccines and vaccination procedures for inducing lactogenic immunity in sows
1989
Moxley, R.A. | Olson, L.D.
Two federally licensed attenuated live transmissible gastroenteritis (TGE) virus vaccines (an IM vaccine and an oral-IM vaccine) and 1 nonlicensed nonattenuated live TGE virus vaccine were evaluated and compared in sows free of TGE virus-neutralizing antibodies. Litters from the sows were challenge exposed at 3 and 5 days of age, and results were combined according to the vaccine administered to the sows. The survivability of pigs suckling sows vaccinated with the nonattentuated vaccine was significantly (P less than 0.01) greater than that of pigs suckling sows vaccinated with the IM attenuated vaccine, significantly (P less than 0.05) greater than that of pigs suckling sows vaccinated with the oral-IM attenuated vaccine, and significantly (P less than 0.05) greater than that of pigs suckling sows that had not been vaccinated. The differences, however, between survivability of litters from sows vaccinated with the IM attentuated vaccine or the oral-IM attenuated vaccine and that of litters from the sows not vaccinated were not significant (P greater than 0.10). The nonattenuated TGE vaccine, although giving a higher level of protection than the attenuated vaccine was eventually overwhelmed. Dexamethasone did not increase the incidence of diarrhea, and levamisole did not potentiate the lactogenic immunity in sows after given their first dose of the nonattenuated vaccine. Survivability in litters suckling sows that developed diarrhea after given their first dose of the nonattenuated vaccine was not greater than that in litters suckling sows that did not develop diarrhea. The best results were obtained when 3-day-old suckling pigs were challenge exposed with virulent TGE virus.
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