Occurrence of canine parvovirus type 2c in diarrhoeic faeces of dogs in Kolkata, India.

Canine parvovirus-2(CPV-2) causes a highly contagious disease of dogs characterised by acute hemorrhagic gastroenteritis, lethargy, vomiting, fever and usually bloody or mucoid diarrhoea. In the present study, 41 faecal samples collected from dogs exhibiting the signs of fever, vomition, bloody or mucoid diarrhoea in Kolkata, India were screened by haemagglutination test and PCR for detection of capsid protein coding VP2 gene. The viral genotype was detected by multiplex PCR and analysis of partial VP2 gene nucleotide sequences of selected PCR products with bioinformatics tool. Thirteen (31.71%) samples were found positive with HA titre ≥ 32 whereas 28 (68.29%) samples were positive by PCR of VP2 gene indicating higher sensitivity of PCR. Highest occurrence of CPV-2 was observed in the age group of 1-6 months (80.65%) and non-descript breeds with no history of vaccination (85%). Three samples were antigenic type CPV-2a, rest were CPV-2b/CPV 2c. Six CPV sequences were found to be highly similar to published CPV 2c sequences in BLAST analysis revealing a maximum identity of 99-100% with other CPV-2c strains and clustered together with CPV-2c strains of India and other countries in phylogenetic analysis. The present study highlights the need for continuous monitoring of samples to detect gradual changes in circulating CPV-2 genotypes in India.

Comparative occurrence of ESBL/AmpC beta-lactamase-producing Escherichia coli and Salmonella in contract farm and backyard broilers.

The present study was conducted to detect the occurrence of beta-lactamase and biofilm-producing Escherchia coli and Salmonella in apparently healthy broiler birds reared in household and contract poultry farms. In total, 150 cloacal swabs were collected from apparently healthy broiler birds of various age groups reared in backyard (n = 100) and contract farms (n = 50) in West Bengal (India). The isolation rate of ESBL producers was significantly more (P < 0·05) reared in contract poultry farms than those reared in backyard. Majority of the E. coli isolates possessed blaCTX-M followed by blaSHV and blaTEM . Majority of the Salmonella strains possessed blaTEM followed by blaCTX-M , and no blaSHV was detected. The selected sequences of the PCR products were found cognate with blaCTX-M-1 , blaCTX-M-2 , blaCTX-M-9 , blaCTX-M-14 , blaCTX-M-15 , blaSHV-12 and blaTEM-52 . The study detected 46·8% of E. coli and 42·5% of Salmonella strains as biofilm producers. Beta-lactamase-producing Enterobacteriaceae strains showed resistance against tetracycline, chloramphenicol, doxycycline, co-trimoxazole and ampicillin and sensitivity to imipenem-EDTA, colistin and gentamicin. The study revealed the partial clonal relationship of ESBL sequences possessed by the poultry isolates of the present study and local clinical isolates available in the database. The study made consumer awareness about careful handling of live birds or poultry meat to avoid the zoonotic transmission of antimicrobial-resistant Enterobacteriaceae.

Multi-drug resistant, biofilm-producing high-risk clonal lineage of Klebsiella in companion and household animals.

Antimicrobial resistance is a global emergency which needs one health approach to address. The present study was conducted to detect the prevalence of beta-lactamase and biofilm-producing Klebsiella strains in rectal swabs (n = 624) collected from healthy dogs, cats, sheep and goats reared as companion or household animals in India. The dogs and cats were frequently exposed to third- or fourth-generation cephalosporins for therapy. The sheep and goats were occasionally exposed to antibiotics and had environmental exposure. Phenotypical ESBL (n = 93) and ACBL (n = 88)-producing Klebsiella were isolated significantly more (P < 0·05) from companion animals than household animals. Majority of the Klebsiella possessed blaCTX-M-15 . The sequences blaCTX-M-15.2 , blaCTX-M-197 and blaCTX-M-225 are reported first time from the companion animals. All ACBL-producing isolates possessed blaAmpC . The present study detected 65·8% of Klebsiella strains as biofilm producers possessing the studied biofilm associated genes. The isolates showed phenotypical resistance against chloramphenicol, tetracycline, doxycycline, co-trimoxazole, ampicillin, cefotaxime/clavulanic acid. The present study showed that companion and household animals (dogs, cats, sheep, goats) may act as a carrier of ESBL/biofilm-producing, multi-drug resistant, high-risk clonal lineage of Klebsiella.

Characterization of beta-lactamase and biofilm producing Enterobacteriaceae isolated from organized and backyard farm ducks.

This study was undertaken to detect the occurrence of beta-lactamase and biofilm producing Enterobacteriaceae in healthy ducks. A total 202 cloacal swabs were collected from ducks kept in organized (n = 92) and backyard (n = 110) farms in West Bengal (India). The ducks had no history of antibiotic intake. Among the 87 phenotypically beta-lactamase producing Escherichia coli, 19 (17·43%), 6 (5·05%) and 15 (13·76%) isolates possessed blaTEM , blaSHV and blaCTX-M respectively. Whereas, 5 (38·46%) Salmonella isolates were found to harbour blaCTX-M . In K. pneumoniae 10 (33·33%), 3 (13·33%), 4 (13·33%) isolates possessed blaTEM , blaSHV and blaCTX-M respectively. The sequences of selected PCR products were found 98% cognate with blaCTX-M-9, blaSHV-12 and blaTEM-1 . Beta-lactamase producing E. coli isolates belonged to 14 different serogroups such as O1, O2, O3, O5, O7, O8, O35, O83, O84, O88, O119, O128, O145 and O157. Moreover, 87 E. coli (79·82%), six Samonella (46·15%) and 13 K. pneumoniae (43·33%) isolates were detected as AmpC producers possessing blaAmpC . Majority of E. coli (46·79%), Salmonella (46·15%) and K. pneumoniae (70%) isolates were detected as biofilm producers and possessed the associated genes (csgA, sdiA, rcsA, rpoS). Significantly higher occurrence of beta-lactamase and biofilm producing Enterobacteriaceae isolates was detected in backyard ducks than organized farms. SIGNIFICANCE AND IMPACT OF THE STUDY: Consumption of antibiotic through feed or during therapy is considered as potential reason for generation of antimicrobial resistant bacteria in birds. This study provides valuable evidence that exposure to contaminated environment may be an additional source for generation of antimicrobial resistant bacteria in backyard ducks. The backyard ducks are reared by marginal farmers in India who cannot offer antibiotics to them either through feed or during therapy due to high cost. The study also reveals a significant correlation between biofilm formation and possession of antimicrobial resistance genes in the bacterial isolates from the ducks.

Detection and characterization of pathogenic Pseudomonas aeruginosa from bovine subclinical mastitis in West Bengal, India.

AIM: Subclinical mastitis in bovines is mainly responsible for the huge economic loss of the dairy farmers, of which Pseudomonas aeruginosa is one of the causative agents. The study was aimed at a screening of suspected milk samples from different cattle farms of West Bengal for detection and confirmation of P. aeruginosa strains followed by their characterization. MATERIALS AND METHODS: Around 422 milk samples were screened from different dairy farms primarily by on-spot bromothymol blue (BTB) test and then in the lab by somatic cell counts (SCC) to finally consider 352 samples for detection of P. aeruginosa. Selective isolation and confirmation of the isolates were done using selective media, viz., cetrimide and Pseudomonas agar followed by confirmation by fluorescent technique. Molecular characterization of the strains was done by polymerase chain reaction for the presence of toxA (enterotoxin A, 352 bp) and exoS (exoenzyme S, 504 bp) genes. RESULTS: Approximately, 371 (87.9%) samples were positive in on-spot BTB test among which 352 (94.8%) samples revealed high SCC values (more than 3 lakh cells/ml) showing infection when screened. Among these, 23 (6.5%) samples yielded typical Pseudomonas sp. isolates out of which only 19 (5.4%) isolates were confirmed to be P. aeruginosa which showed characteristic blue-green fluorescence due to the presence of pigment pyoverdin under ultraviolet light. Out of these 19 isolates, 11 isolates were positive for toxA, 6 isolates for exoS, and 2 for both these pathogenic genes. CONCLUSION: Approximately, 5.4% cases of bovine subclinical mastitis infections in South Bengal were associated with P. aeruginosa which possess pathogenic genes such as toxA (63.2%) and exoS (36.8%).

Detection and characterization of zoonotic dermatophytes from dogs and cats in and around Kolkata.

AIM: The ringworms of pet dogs, cats, and stray animals (dogs, cats, and other animals) could be a potential source of zoonotic infections causing a serious public health problem in the busy city Kolkata. The pet owners are more susceptible to get this infection from their pets, because of the close contact with them as dermatophytosis is very much prevalent in those pets. So, this study was aimed to check the prevalence of dermatophytosis in dogs, cats, and in pet owners. MATERIALS AND METHODS: A total of 362 clinically suspected cases of dermatophytosis from dogs (123 in number), cats (202 in number), and human beings (37 in number) were collected and studied from in and around Kolkata to detect the presence of significant dermatophytes. Direct microscopy and cultural examination of the isolates were performed following standard methodology. Identification and characterization of the isolates were done by different biochemical tests. RESULTS: Samples (n=285) having significant dermatophytic fungal infections were found to be of highest number in cats (158, 55.5%) than in dogs (108, 37.8%) and humans (19, 6.7%), respectively. The incidence of Microsporum canis (60.0%) was the highest from affecting dogs, cats, and human beings in comparison to Microsporum gypseum (22.5%), Trichophyton mentagrophytes (15.8%) and Trichophyton rubrum (1.7%). Detection of T. rubrum was only from human cases in this study, whereas the presence of rest three were slightly higher in cats than that of the dogs and humans in this present study. The incidences were higher in young animals and in humans of the age group of 21-30 years, during the rainy season (from April to August) and also in in-contact human beings. CONCLUSION: M. canis was the most commonly pathogen among all causing dermatophytosis in animals and also in the pet owners. M. gypseum and T. mentagrophytes were other pathogens associated with these infections. These infections were more prevalent in the rainy seasons and in in-contact human patients or pet owners.

Serogroup distribution and virulence characteristics of sorbitol-negative Escherichia coli from food and cattle stool.

AIMS: To (i) study the serogroup distribution and virulence characteristics of non-sorbitol-fermenting Escherichia coli isolates from foods of animal origin and cattle faeces and (ii) re-examine the true sorbitol and beta-D-glucuronidase (GUD) reactions of sorbitol-negative (Sor(-)) strains from MacConkey sorbitol agar (SMAC) to assess their phenotypic similarity with E. coli O157. METHODS AND RESULTS: One hundred and thirty Sor(-)E. coli were isolated from 556 food samples and 177 cattle stool samples using cefixime tellurite-supplemented SMAC (CT-SMAC) and chromogenic HiCrome MS.O157 agar respectively. Based on typing of somatic antigen, the isolates were classified into 38 serogroups. PCR results identified about 40% strains, belonging to O5, O8, O20, O28, O48, O60, O78, O82, O84, O101, O110, O123, O132, O156, O157, O-rough and OUT as Shiga toxigenic. Majority of O5, O84, O101, O105, O123, O157, O-rough and OUT strains were enterohaemolytic. Further, 39.2% and 63.1% of Sor(-) isolates from CT-SMAC fermented sorbitol in phenol red broth and hydrolysed 4-methylumbelliferyl-beta-D-glucuronide (MUG) respectively. Members of serogroups O5, O28, O32, O81, O82, O84, O101, O-rough lacked both the sorbitol fermentation (broth test) and GUD activity and might create confusion in phenotypic identification of E. coli O157. CONCLUSIONS: Sor(-)E. coli isolates from raw meat, milk, shrimp and cattle stool belonged to 38 serogroups, with E. coli O157 constituting only 14.6% of the isolates. Many of these nonclinical Sor(-) strains were potentially pathogenic. Nearly 39% of these Sor(-)E. coli from CT-SMAC fermented sorbitol in broth, indicating the need for confirmation of sorbitol reaction in broth. SIGNIFICANCE AND IMPACTS OF THE STUDY: Classical sorbitol utilization and GUD tests are not likely definitive tests for E. coli O157. Further improvement of differential media based on these phenotypic properties is necessary for detection of pathogenic serotypes from foods and environmental samples.

Occurrence, virulence characteristics and antimicrobial resistance of Escherichia coli O157 in slaughtered cattle and diarrhoeic calves in West Bengal, India.

AIMS: (i) To study the occurrence of Escherichia coli serotype O157 in cattle stool in West Bengal, India, and (ii) the virulence properties and antimicrobial resistance of the E. coli isolates. METHODS AND RESULTS: Following enrichment in modified EC broth and plating onto HiCrome MS.O157 agar, a total of 14 strains of E. coli serotype O157 was isolated from faecal samples from two (2.04%) slaughtered cattle and six (7.59%) diarrhoeic calves. By multiplex PCR, Shiga toxin genes were detected in all the isolates. The enterohaemolysin phenotype was found in all, but one strain. Among 14 strains, ten were resistant to at least one of the antimicrobial agents tested. Multiple antibiotic resistance was frequent. CONCLUSIONS: The study showed that occurrence of Shiga toxin-producing and multiple antibiotic-resistant E. coli O157 among cattle population in this region of India is significant. SIGNIFICANCE AND IMPACT OF THE STUDY: Considering routine human contacts with cattle, a large human population in this region may be at risk for exposure to Shiga toxin-producing E. coli O157.