Veterinary Research Forum

Abstract This study was important to improve proper biosecurity measures and controlling the spread of Aeromonas to prevent future outbreaks. This research sought to determine whether virulent Aeromans species were present in morbid rainbow trout, their resistance and their genetic relatedness. A total number of 542 tissue lesion specimens were collected from gill, liver, heart and kidneys in morbid domesticated fish in Duhok province, Iraq. The gyrB DNA sequence analysis was used to determine the species classification. Drug susceptibility testing was conducted for all isolated strains using disc diffusion technique. The genotyping analysis was carried out using enterobacterial repetitive intergenic consensus-polymerase chain reaction. Thirty-four isolates were found and they were classified into three species (Aeromonas veronii, Aeromonas sorbia, and Aeromonas allosaccharophila), where A. veronii stand as one of the most prevalent species. The most frequently affected organ by Aeromonas was the gills among four different organs. The detection frequencies of the virulence genes aerolysin, outer membrane protein, glycerophospholipid-cholesterol acyltransferase, elastase, flagella, serine protease, cytotonic heat-labile, and hemolysin were 100%, 100%, 79.41%, 64.70%, 76.47%, 67.64%, 70.58%, and 41.17, respectively. None of the strains possessed all of the virulence markers. All isolates were completely resistant to ceftazidime, amoxicillin and doxycycline. All isolates were found to be multi-drug-resistant. Regardless of the nearest geographic source area of samples and the same Aeromonas species, there was a high genetic diversity. The results of this study could help farmers and researchers make informed decisions about measures of biosecurity and proper therapeutic drugs to apply to prevent current outbreaks and prevent them from recurring again.

Abstract Pasteurella multocida exists as a commensal in the upper respiratory tracts of livestock, and poultry, and causes a wide variety of diseases in humans and animals. This study aimed to investigate the incidence of P. multocida by bacteriological and molecular characterization in sheep and goats and screening the existence of capsule-specific genes and their antibiotic resistance pattern. Totally, 1650 nasopharyngeal swabs were collected from apparently healthy sheep and goats and 460 lung tissues were collected from slaughtered animals in Fars province, Iran. All samples were cultured and suspected colonies were examined by biochemical tests, antimicrobial assay and polymerase chain reaction (PCR). Among 165 P. multocida (104 sheep and 61 goats) isolates, the capA, capD, and capB genes were amplified in 98, 48, and 12 isolates, respectively. The occurrence of four virulence-associated genes of P. multocida isolates were determined by PCR. Most isolates harbored the toxA (79.40%) and hgbB genes (70.90%) and 59.40% of isolates had the pfhA gene. Almost half of the isolates (46.10%) contained the tbpA gene. According to the current study, P. multocida capsular type A had the most frequency followed by type D. In addition, the high frequency of tbpA, pfhA, toxA, and hgbB genes revealed that these genes are possibly important in the pathogenesis of P. multocida. Oxytetracycline, enrofloxacin, florfenicol, and tilmicosin were the most effective drugs.

Abstract Vibrio species are significant pathogens affecting aquatic species. Around 12 species of Vibrio can cause a gastrointestinal illness (gastroenteritis) in humans resulting from eating contaminated food such as raw or undercooked shellfish. The indiscriminate use of antibiotics accelerates the development of resistance representing a severe challenge for controlling Vibrio outbreaks. In this study, the antibiotic resistance profile and the prevalence of pathogenic Vibrio species of apparently healthy and diseased fishes isolated from different types of fish in Kafr EL-Sheikh Governorate in Egypt during 2018 were determined. Samples obtained from fishes were inoculated onto a Vibrio-selective medium (TCBS) and phenotypically identified using the biochemical characteristics and representative cultures were checked by PCR to confirm the identified isolates. In the present study, V. alginolyticus (16.00%) was the predominant species followed by V. cholerae (7.33%) and V. parahaemolyticus (5.33%). The tested isolates were resistant to ampicillin (80.00%) and sensitive to ciprofloxacin and norfloxacin (100%). A total number of 15 Vibrio isolates (5 Vibrio parahaemolyticus, 5 V. alginolyticus, and 5 V. cholerae) were screened for five housekeeping genes and pathogenic virulence markers by PCR. Results showed that 100% of the V. parahaemolyticus isolates carried the tlh gene and 60.00% carried the tdh gene. In V. alginolyticus, 100% of the isolates carried the collagenase gene 0.00% carry the tdh gene; and 80.00% of V. cholerae isolates carried the ctx gene. The results showed that many isolates in this study had virulence characteristics that might correspond with the potential of infections and diseases.

Abstract Lamb enteritis constitutes an economic burden on sheep production worldwide. We aimed to estimate the prevalence of Shiga toxin-producing Escherichia coli (STEC) and Salmonellae among diarrheic lambs at Kafrelsheikh Governorate, Egypt and to detect the associated clinical, hematologic, biochemical, and antioxidant parameters. Fifty diarrheic and twenty apparently healthy control lambs were examined clinically, and hematologically. Diarrheic lambs had a significant elevated body temperature, respiratory and pulse rate, most of hemogram para-meters, total proteins and albumin, oxidative stress markers malonaldiahyde and nitric oxide levels, liver enzymes, urea and creatinine than control group. On the other hand, these diarrheic lambs had significant reduction in total leukocyte count and lymphocytes, antioxidant biomarkers super oxide dismutase activities and reduced glutathione than control lambs. E. coli and Salmonella spp. were isolated from 32.00% and 16.00% of diseased lambs, respectively. Serotyping and biochemical tests of examined samples identified 16 E. coli isolates belonged to 10 different serotypes; O6, O8, O26:H11, O75, O84:H21, O103:H2, O114:H4, O121:H7, O128:H2 and O163:H2. All isolates are STEC as they harbor either Shiga-toxin 1 or Shiga-toxin 2 genes or both. One isolate carries intimin gene (eaeA) and classified as EHEC; O26:H11. The obtained nine isolates of Salmonella carry enterotoxin (Stn) genes, eight of them carry hyper-invasive locus (hilA) gene, all isolates belonged to six serotypes; S. Enteritidis, S. Heidelberg, S. Tsevie, S. Typhimurium, S. Essen, and S. Infantis. Lamb diarrhea was prevalent in the studied area and might constitute a veterinary and public health threat. Alteration in hemato-biochemical para-meters and oxidative–anti-oxidant balance could help adopt appropriate treatment regimens.

Abstract Escherichia coli associated infections are major threats in poultry industry owing to severe economic losses each year. This study was conducted to identify E. coli isolates, to evaluate their antibiotic sensitivity and to find out their virulence patterns from infected broilers of Sylhet city in Bangladesh. Using polymerase chain reaction, a total 20 isolates were identified as E. coli from 11 chickens, exhibiting symptoms like colibacillosis and/or diarrhea. All isolates were positive for type-1 fimbrial adhesion (fimH), followed by putative avian hemolysin (hlyF) in 17 isolates; while none of the isolates was amplified with intimin (eaeA). Among 10 tested antibiotics, 100% of the isolates (n = 20) showed resistance to ampicillin, amoxicillin and tetra-cycline; but they were 100% sensitive to gentamicin. Organ specific correlations of antibiotic sensitivity were obtained among the isolates through principal component analysis (PCA) and Agglomerative Hierarchical Clustering (AHC). The 16S rRNA data of two multi-drug resistant isolates revealed closed clustering with clinical E. coli strains which could be indication of their zoonotic potential. In conclusion, the results depict higher prevalence of fimH and hlyF genes and drug resistance patterns of E. coli isolates from broilers in Sylhet city of Bangladesh.

Abstract Avian pathogenic Escherichia coli (APEC) are responsible for wide ranges of extra-intestinal diseases in poultry including colibacillosis, cellulitis, coligranuloma and yolk sac infection. Numbers of virulence are considered important in the pathogenicity of these diseases. The aims of the present study were phylogenetic typing and virulence genes detection in Escherichia coli isolates from colibacillosis and cellulitis of broiler chickens in poultry slaughterhouses of Shahrbabak region, Kerman, Iran. A total number of eighty three E. coli isolates were taken from broiler chickens with colibacillosis and thirty four isolates were taken from carcasses with cellulitis in the industrial slaughterhouses. Biochemically confirmed E. coli isolates were subjected to polymerase chain reaction assay to determine phylogenetic groups and presence of pap C, sfa/focDE, iucD, afaIB-C, hlyA, fimH and crl virulence genes. Colibacillosis isolates were belonged to A (54.21%), B1 (7.22%), B2 (6.03%) and D (32.53%) phylogroups. Whereas, the isolates from cellulitis cases were belonged to three main phylogroups; A (55.88%), B1 (5.88%) and D (38.24%). Statistical analysis showed a specific association between the presence of crl virulence gene and phylogroups of A and D in colibacillosis isolates. The results showed that the isolates from both diseases in broiler chickens could be assigned to various phylogenetic groups (mainly A(. Also, the virulence genes profile of cellulitis E. coli is completely different from that of colibacillosis in this region.