Isolation and characterization of Escherichia coli serotype O157:H7 and other verotoxin-producing E. coli in healthy Indian cattle

Research (Published online: 29-10-2020)

32. Isolation and characterization of Escherichia coli serotype O157:H7 and other verotoxin-producing E. coli in healthy Indian cattle

Dasharath B. Shinde, Surbhi Singhvi, Santosh S. Koratkar and Sunil D. Saroj

Veterinary World, 13(10): 2269-2274

ABSTRACT

Background and Aim: Cattle are the main reservoir of Escherichia coli O157:H7 and other verotoxigenic E. coli (VTEC); therefore, there is an increased risk of infection to humans by either direct or indirect mode of transmissions. However, the prevalence of E. coli O157:H7 in the healthy cattle population of India is yet to be ascertained. This study aimed to screen the dairy cattle in and around Pune, Maharashtra, India, for verotoxin-producing E. coli O157:H7.

Materials and Methods: A total of 257 rectal swabs were collected from 15 different organized and unorganized dairy farms of Pune during the period, January-March 2015. The screening involved enrichment in EC broth followed by differential identification on MacConkey sorbitol agar. The presumptive positive isolates were further confirmed by multiplex polymerase chain reaction (PCR) using primers specific to rfbE (O157), fliC (H7), VT1 (MK1), and VT2 (MK2). Vero-toxicity and antibiotic sensitivity were examined in PCR confirmed isolates.

Results: Out of the 257 samples analyzed, 1.9% (2/105) were positive for O157:H7 and 39% (41/105) were positive for VTEC. Two PCR confirmed positive O157:H7 strains and two randomly selected PCR-positive VT strains exhibited in vitro cytopathic effect on Vero cells on day-7 post-inoculation. Antibiotic sensitivity profiling of O157:H7 strains exhibited resistance against penicillin G, kanamycin, ampicillin, tetracycline, gentamycin, cefotaxime, streptomycin, and piperacillin.

Conclusion: These findings reveal the presence of pathogenic E. coli O157:H7 in the healthy cattle of Pune; in a situation, wherein regular surveillance for O157:H7 is not a norm. Therefore, the findings presented herein warrant routine surveillance and public awareness to prevent the transfer of such pathogens and manage health risks to the public.

Keywords: cattle, Escherichia coli O157:H7, shiga toxin, vero cells, verotoxin.

Short-term effects of sildenafil in the treatment of dogs with pulmonary hypertension secondary to degenerative mitral valve disease

Research (Published online: 29-10-2020)

31. Short-term effects of sildenafil in the treatment of dogs with pulmonary hypertension secondary to degenerative mitral valve disease

Karun Saetang and Sirilak Disatian Surachetpong

Veterinary World, 13(10): 2260-2268

ABSTRACT

Background and Aim: Pulmonary hypertension (PH) is a common complication of degenerative mitral valve disease (DMVD). Sildenafil, a phosphodiesterase-5 inhibitor, has effects in reducing pulmonary arterial pressure by selectively dilating pulmonary vessels. The study aimed to evaluate the effects of sildenafil in combination with conventional therapy in dogs with PH caused by DMVD.

Materials and Methods: Fourteen dogs diagnosed with PH secondary to DMVD Stage C on conventional therapy were randomly assigned to placebo (n=7) and sildenafil (n=7) groups. On day 0, the recruited dogs underwent physical examinations, clinical score assessments, electrocardiography, systolic blood pressure measurements, blood collection, thoracic radiography, and echocardiography for baseline. The dogs then received a combination of conventional therapy with sildenafil or placebo every 8 h for 1 week. On day 7, all dogs underwent the baseline evaluations again.

Results: The sildenafil group experienced a significant decrease in estimated systolic pulmonary artery pressure (sPAP) (p=0.043) from day 0 to day 7. Moreover, the total clinical scores were decreased in dogs treated with sildenafil relative to those who received the placebo (p=0.007); however, the lung scores were not different between before and after treatment with sildenafil.

Conclusion: Sildenafil had a synergistic effect with conventional therapy in reducing the estimated sPAP and clinical scores in dogs with PH secondary to DMVD.

Keywords: degenerative mitral valve disease, dogs, pulmonary hypertension, sildenafil.

Current advances in molecular subtyping using multilocus variable number of tandem repeat analysis of Salmonella Enteritidis and Salmonella Typhimurium in Egyptian chickens

Research (Published online: 28-10-2020)

30. Current advances in molecular subtyping using multilocus variable number of tandem repeat analysis of Salmonella Enteritidis and Salmonella Typhimurium in Egyptian chickens

Wafaa M. M. Hassan, Ashraf A. Abd El Tawab and Sara M. El-Shannat

Veterinary World, 13(10): 2252-2259

ABSTRACT

Aim: This study aimed to characterize the genetic diversity, evolutionary level, and prevalence of genotypes of common isolates of Salmonella (Salmonella Enteritidis and Salmonella Typhimurium). Using one of the most advanced molecular recognition techniques, multilocus variable number of tandem repeat analysis (MLVA), we characterized the genotype and prevalence of S. Enteritidis and S. Typhimurium.

Materials and Methods: One hundred and twenty-five internal organ samples were collected from the major chicken slaughterhouses in Egypt, and Salmonella species were isolated. PCR was utilized to amplify the IE-1 and Flic-C genes to identify S. Enteritidis and S. Typhimurium DNA, respectively, from Salmonella isolates. MLVA was applied on nine samples of S. Enteritidis DNA and three samples of S. Typhimurium DNA. Six variable number tandem repeat (VNTR) loci (Sal02, Sal04, Sal06, Sal10, Sal20, and Sal23) were amplified.

Results: Of the examined samples (n=125), a total of 12 isolates (9.6%) were either identified as Enteritidis or Typhimurium. PCR-mediated amplification of IE-1 and Flic-C revealed that 75% (n=9) of the 12 Salmonella isolates were S. Enteritidis and 25% (n=3) were S. Typhimurium. The six loci amplified through MLVA had allelic diversity. The most discriminatory heterogenic locus for S. Enteritidis was Sal20. Sal04 and Sal23 were the most discriminatory heterogenic loci for S. Typhimurium. VNTR allelic profile analysis revealed nine unique genotypes for S. Enteritidis and three for S. Typhimurium.

Conclusion: This study was the first to use MLVA analysis to identify S. Enteritidis and S. Typhimurium strains isolated from chickens in Egypt. The molecular typing data reported herein allowed us to characterize the genotypes of S. Enteritidis and S. Typhimurium that are most prevalent in Egyptian chickens. Moreover, this epidemiological information provides valuable insight on how to prevent disease transmission. Moreover, our methods provide an alternative to traditional serotyping techniques that may produce inaccurate strain identifications for organisms with rough lipopolysaccharide structures.

Keywords: lipopolysaccharides, multilocus variable number of tandem repeat analysis, Salmonella, serotyping.

Evaluating Flinders Technology Associates card for transporting bacterial isolates and retrieval of bacterial DNA after various storage conditions

Research (Published online: 28-10-2020)

29. Evaluating Flinders Technology Associates card for transporting bacterial isolates and retrieval of bacterial DNA after various storage conditions

Azhar G. Shalaby, Neveen R. Bakry, Abeer A. E. Mohamed and Ashraf A. Khalil

Veterinary World, 13(10): 2243-2251

ABSTRACT

Background and Aim: Flinders Technology Associates (FTA) cards simplify sample storage, transport, and extraction by reducing cost and time for diagnosis. This study evaluated the FTA suitability for safe transport and storage of Gram-positive and Gram-negative bacterial cells of animal origin on its liquid culture form and from organ impression smears (tissues) under the same routine condition of microbiological laboratory along with detecting their nucleic acid over different storage conditions.

Materials and Methods: Increase in bacterial count from 104 to 107 (colony-forming units/mL) of 78 isolates representing seven bacterial species was applied onto cards. FTA cards were grouped and inoculated by these bacteria and then stored at different conditions of 24-27°C, 4°C, and –20°C for 24 h, for 2 weeks, for 1 and 3 month storage, respectively. Bacteriological examination was done, after which bacterial DNA was identified using specific primers for each bacterial type and detected by polymerase chain reaction (PCR).

Results: The total percentage of recovered bacteria from FTA cards was 66.7% at 24-27–C for 24 h, the detection limit was 100% in Gram-positive species, while it was 57.4% in Gram-negative ones. Regarding viable cell detection from organ impression smears, it was successful under the previous conditions. No live bacterial cells were observed by bacteriological isolation rather than only at 24-27°C for 24 h storage. All bacterial DNA were sufficiently confirmed by the PCR technique at different conditions.

Conclusion: Overall, the FTA card method was observed to be a valid tool for nucleic acid purification for bacteria of animal origin in the form of culture or organ smears regardless of its Gram type and is used for a short time only 24 h for storage and transport of live bacteria specifically Gram-positive type. Moreover, the bacterial nucleic acid was intact after storage in –20°C for 3 months and was PCR amplifiable.

Keywords: bacteria, colony-forming units, Flinders Technology Associates, nucleic acid, polymerase chain reaction.

Seroprevalence of Brucella abortus in cattle in Southern Lebanon using different diagnostic tests

Research (Published online: 28-10-2020)

28. Seroprevalence of Brucella abortus in cattle in Southern Lebanon using different diagnostic tests

Hussein Hassan, Ali Salami, Ghassan Ghssein, Jeanne El-Hage, Nada Nehme and Rana Awada

Veterinary World, 13(10): 2234-2242

ABSTRACT

Background and Aim: Brucellosis is endemic zoonotic and highly contagious bacterial disease. Recently, several brucellosis cases were reported in Lebanon, causing significant economic losses; however, no study was done so far on farms located in the southern part of the country. Thus, the aim of our study was to estimate the prevalence of Brucella abortus in South Lebanon using three different serological tests in the diagnosis of brucellosis in cattle.

Materials and Methods: Seventeen farms from 14 locations in Southern Lebanon were selected. Two hundred and three bovine blood samples of different ages, and 121 milk samples collected from older than 2 years cattle were tested using different serological tests: Rose Bengal test (RBT), milk ring test (MRT), indirect enzyme-linked immunosorbent assay (I-ELISA), and confirmed with competitive ELISA (C-ELISA).

Results: Results revealed that approximately 15.3% (confidence interval [CI] 95 10.3-20.2%) and 15.7% (CI 95 9.2-22.2%) of samples were positive using RBT and MRT, respectively. This percentage was significantly higher when using I-ELISA (18.3%) (CI 95 12.9-23.5%) and C-ELISA (18.7%) (CI 95 9.8-27.5%). Among used diagnostic tests, our results showed that ELISA was more accurate for the detection of brucellosis, especially since it detects the late stages of the infection, which is characterized by the presence of immunoglobulin G. The seroprevalence of brucellosis was higher among females. All positive tests were of cattle Holstein breed older than 2 years. Tyre and Jezzine cities had a higher significance in bovine brucellosis than Saida. A positive correlation between human and cattle brucellosis was found.

Conclusion: Our results showed that bovine brucellosis is prevalent in southern Lebanon. Lack of research, in addition to little feedback of occurring illness or symptoms, creates a gap in helping to control the spread of the disease.

Keywords: Brucellosis, Brucella abortus, diagnostic tests, prevalence, Southern Lebanon.

Gastrointestinal parasite infection intensity and hematological parameters in South African communal indigenous goats in relation to anemia

Research (Published online: 27-10-2020)

27. Gastrointestinal parasite infection intensity and hematological parameters in South African communal indigenous goats in relation to anemia

Takalani Judas Mpofu, Khathutshelo Agree Nephawe and Bohani Mtileni

Veterinary World, 13(10): 2226-2233

ABSTRACT

Aim: The study was conducted to determine the intensity of gastrointestinal parasite (GIP) infections and hematological parameters in South African communal indigenous goats in relation to anemia.

Materials and Methods: A total of 288 goats were randomly sampled in areas representing four agro-ecological zones. Fecal and blood samples were collected from the rectum and jugular vein, respectively, of each animal. The number of eggs per gram (EPG) and oocysts per gram (OPG) of feces and the hematological parameters were determined using the modified McMaster technique and a BC-2800Vet® automatic hematology analyzer, respectively. Data were analyzed using the repeated measures techniques of Minitab 17, modeling the covariance structure of the observed data.

Results: Based on EPG and OPG, goats in humid zone were significantly infected (p<0.05) with strongyles, Eimeria, Moniezia, and Trichuris spp. Hematological parameters of goats in arid and humid zone were lower (p<0.05) than those in semi-arid and dry sub-humid zone. GIP infection intensities were higher (p<0.05) in young animals than in adult and suckling goats. GIP infection intensity was similar between goat sexes, while hematological parameters were higher (p<0.05) in females. Higher (p<0.05) infection intensities for strongyles (302.90 EPG) and Eimeria (216.09 EPG) were observed in winter compared to summer (strongyles: 302.90, Eimeria: 216.09 EPG). Higher (p<0.05) values for the hematological parameters were observed during summer compared to that in winter.

Conclusion: GIP infection intensity in the winter could be associated with hypochromic and normocytic anemia which likely to affects suckling goats while in the summer could be associated with normochromic and normocytic anemia which likely to affect young goats.

Keywords: hemoglobin concentration, mean corpuscular hemoglobin, packed cell volume, strongyles.

Effectivity of zinc oxide-turmeric extract dressing in stimulating the reepithelization phase of wound healing

Research (Published online: 27-10-2020)

26. Effectivity of zinc oxide-turmeric extract dressing in stimulating the reepithelization phase of wound healing

Asti Meizarini, Aryati Aryati, Devi Rianti, Wibi Riawan and Astari Puteri

Veterinary World, 13(10): 2221-2225

ABSTRACT

Background and Aim: Reepithelialization can be described as the resurfacing of a wound with new epithelium in the process of healing, with the overlapping step from keratinocyte migration and proliferation to the tissue contraction. Zinc oxide-turmeric extract dressing has been proven to have anti-inflammatory properties, but its effectivity in the reepithelialization process is still unknown. This study aimed to determine the effect of a wound dressing consisting of zinc oxide and turmeric extract on wound reepithelialization by assessing the expression of cytokeratin 14 (CK14), epidermal growth factor receptor (EGFR), and epithelial cadherin (E-cadherin).

Materials and Methods: A total of 40 Wistar rats were randomized into four control and four treatment groups (n=5 per group). On day 1, a square-shaped full-thickness skin excision measuring 6×6 mm in size was created in the dorsal thoracic area of the rats, and the wounds were either dressed with a combination of zinc oxide and turmeric extract in the treatment groups or left undressed in the control groups. Then, the rats were sequentially sacrificed on days 3, 5, 7, and 14 to obtain subepithelial excision samples, which were subsequently subjected to immunohistochemistry analysis for the expression of CK14, EGFR, and E-cadherin to ascertain wound reepithelization. The data were tabulated and analyzed using a one-way analysis of variance and least significant difference test.

Results: The highest expression levels of CK14, EGFR, and E-cadherin were observed on days 7 and 14 in the treatment and control groups, respectively. While the expression levels of these markers on day 7 were found to be significantly higher in the treatment than the control groups, no significant difference in the expression levels on day 14 was detected between the control and treatment groups (p<0.05).

Conclusion: A wound dressing consisting of zinc oxide and turmeric extract can help accelerate reepithelization in the wound healing process.

Keywords: cytokeratin 14, epithelial cadherin, epidermal growth factor receptor, turmeric extract, wound dressing.