Molecular and immunological characterization of Hyalomma dromedarii and Hyalomma excavatum(Acari: Ixodidae) vectors of Q fever in camels

Research (Published online: 12-08-2018)

14. Molecular and immunological characterization of Hyalomma dromedarii and Hyalomma excavatum(Acari: Ixodidae) vectors of Q fever in camels

Hend H. A. M. Abdullah, Eman E. El-Shanawany, Sobhy Abdel-Shafy, Hala A. A. Abou-Zeina and Eman H. Abdel-Rahman

Veterinary World, 11(8): 1109-1119

ABSTRACT

Background and Aim: Q fever Coxiella burnetii is a worldwide zoonotic disease, and C. burnetii was detected in mammals and ticks. Ticks play an important role in the spread of C. burnetii in the environment. Therefore, the aims of this study were to detect Q fever C. burnetii in camels and ixodid ticks by molecular tools and identification of Hyalomma dromedarii and Hyalomma excavatum using molecular and immunological assays.

Materials and Methods: A total of 113 blood samples from camels and 190 adult ticks were investigated for the infection with C. burnetii by polymerase chain reaction (PCR) and sequencing the targeting IS30A spacer. The two tick species H. dromedarii and H. excavatum were characterized molecularly by PCR and sequencing of 16S ribosomal RNA (16S rRNA) and cytochrome oxidase subunit-1 (CO1) genes and immunologically by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blot.

Results: A total of 52 camels (46%) were positive for Q fever infection. Only 10 adult ticks of H. dromedarii were infected with C. burnetii. The IS30A sequence was around 200 bp in length for C. burnetii in H. dromedariiticks with a similarity of 99% when compared with reference data in GenBank records. The length of 16S rDNA and CO1 was 440 and 850 bp, respectively, for both H. dromedarii and H. excavatum. The phylogenetic status of H. dromedarii was distant from that of H. excavatum. SDS-PAGE revealed seven different bands in the adult antigens of either H. dromedarii or H. excavatum with molecular weights ranged from 132.9 to 17.7 KDa. In western blot analyses, the sera obtained from either infested camel by H. dromedarii or infested cattle by H. excavatum recognized four immunogenic bands (100.7, 49.7, 43.9, and 39.6 kDa) in H. dromedariiantigen. However, the infested camel sera identified two immunogenic bands (117 and 61.4 kDa) in H. excavatum antigen. Furthermore, the sera collected from cattle infested by H. excavatum recognized three immunogenic bands (61.4, 47.3, and 35 kDa) in H. excavatum antigen.

Conclusion: Molecular analyses indicated that both camels and ticks could be sources for infection of animals and humans with Q fever. Furthermore, the molecular analyses are more accurate tools for discriminating H. dromedarii and H. excavatum than immunological tools.

Keywords: 16S ribosomal DNA, Coxiella burnetii, cytochrome oxidase subunit-1, hard ticks, phylogeny, polymerase chain reaction, sequence, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, western blot.

Prevalence and risk factors for Salmonella spp. contamination in broiler chicken farms and slaughterhouses in the northeast of Algeria

Research (Published online: 10-08-2018)

13. Prevalence and risk factors for Salmonella spp. contamination in broiler chicken farms and slaughterhouses in the northeast of Algeria

Samia Djeffal, Bakir Mamache, Rachid Elgroud, Sana Hireche and Omar Bouaziz

Veterinary World, 11(8): 1102-1108

ABSTRACT

Aim: The aim of this study was to provide information on the prevalence of Salmonella serotypes and to identify risk factors for Salmonella spp. contamination in broiler chicken farms and slaughterhouses in the northeast of Algeria.

Materials and Methods: This study was conducted on 32 poultry farms and five slaughterhouses in the province of Skikda (northeastern Algeria). A questionnaire was answered by the poultry farmers and slaughterhouses' managers. Biological samples (cloacal swabs, droppings, caeca, livers, and neck skins) and environmental ones (water, feed, surface wipes, rinsing water, and sticking knife swabbing) were taken to assess the Salmonella contamination status.

Results: Nearly 34.37% of the poultry farms and all the slaughterhouses were contaminated with Salmonella. The isolated Salmonella strains belonged to two major serotypes: Kentucky and Heidelberg followed by Enteritidis, Virginia, and Newport. There was an evident heterogeneous distribution of serotypes in poultry farms and slaughterhouses. Only one factor (earth floor) was significantly associated with Salmonellacontamination in poultry houses (p<0.05).

Conclusion: A high prevalence rate of Salmonella contamination was found in poultry farms and slaughterhouses in Skikda region. These results showed the foremost hazardous role of poultry production in the spread and persistence of Salmonella contamination in the studied region.

Keywords: poultry, prevalence, risk factor, Salmonella, serotype, slaughterhouse.

A cross-sectional study of the welfare of calves raised in smallholder dairy farms in Meru, Kenya, 2017

Research (Published online: 10-08-2018)

12. A cross-sectional study of the welfare of calves raised in smallholder dairy farms in Meru, Kenya, 2017

Emily K. Kathambi, John A. Van Leeuwen, George K. Gitau and Shawn L. McKenna

Veterinary World, 11(8): 1094-1101

ABSTRACT

Aim: This study was aimed at describing calf comfort and determining the individual and pen level factors that affect comfort status (in particular, calf leg hygiene scores) of smallholder dairy farms in Meru County, Kenya.

Materials and Methods: A cross-sectional study was carried out on 52 calves that were up to 1 year old in 38 dairy farms (mean±standard deviation: Herd size=1.71±0.7 milking cows and milk production=6.7±3.1 L/day) in Meru, Kenya, in 2017, with the intention to describe their comfort and determine the factors associated with leg hygiene as a critical parameter for calf comfort assessment. Calves' biodata, health status, and leg hygiene were assessed, along with pen characteristics such as area, hygiene, and knee impact and knee wetness scores, while a questionnaire was administered to the farmers to gather information regarding calf housing management practices in the farm.

Results: The calves had a mean body weight of 85.2±32.8 kg and average daily weight gain of 0.50±0.45 kg per day. 71% of calves had a good body condition score (≥2.5), and the mean space allowance per calf was 2.52±1.56 m2. Approximately 75% of the calves (39/52) were kept in pens, and the rest were reared outdoors. For 39 calves kept indoors, 26% (10/39) of them had wooden or concrete floors while 74% (29/39) had dirt floors. Nearly two-thirds (62%) of indoor calves (26/39) were reared in pens with bedding, and 23% (9/39) and 33% (13/39) of the calves reared indoors were kept in pens displaying a failed knee impact test and failed knee wetness test. Indoor housed calves had an increased probability of having dirty calf legs (cleanliness score of >2.5) by 8.6 times (p=0.031), compared to outdoor-housed calves. In the final multivariable logistic regression model of 39 calves in pens, concrete or wood floors (odds ratio [OR]=7.9, p=0.047), poor body condition (OR=17.1, p=0.020) and use of bedding (OR=12.5, p=0.046) appeared to be positively correlated with dirtiness of calf legs, compared to dirt floors, good body condition, and no bedding, respectively.

Conclusion: Overall, some calf comfort aspects were covered for the majority of calves examined, but 69% of the pens were categorized as dirty, especially those with wooden or concrete floors and poor bedding management. Smallholder dairy farmers in Kenya should be trained on calf housing management to improve calf comfort and productivity.

Keywords: calf comfort, calf hygiene, dairy calves, Kenya.

Determination of hematological and serum biochemical reference values for indigenous sheep (Ovies aries) in Dhaka and Chittagong Districts of Bangladesh

Research (Published online: 09-08-2018)

11. Determination of hematological and serum biochemical reference values for indigenous sheep (Ovies aries) in Dhaka and Chittagong Districts of Bangladesh

Md. Kaisar Rahman, Shariful Islam, Jinnat Ferdous, Md. Helal Uddin, Muhammad Belal Hossain, Mohammad Mahmudul Hassan and Ariful Islam

Veterinary World, 11(8): 1089-1093

ABSTRACT

Aim: The study was aimed to determine the reference values of most commonly used hematological and biochemical parameters of indigenous sheep, reared under semi-intensive backyard farms in Dhaka and Chittagong district, Bangladesh.

Materials and Methods: A total of 41 blood samples were collected from indigenous sheep (Ovis aries) from June to December 2016 from Dhaka and Chittagong Districts of Bangladesh. Hematological and serum biochemical parameters such as hemoglobin (Hb), packed cell volume (PCV), erythrocyte sedimentation rate (ESR), total erythrocyte count (TEC), total leukocyte count (TLC), neutrophil, eosinophil, basophil, monocyte, lymphocyte, urea, triglyceride, cholesterol, glucose, albumin, total protein (TP), alanine aminotransferase (ALT), and aspartate transaminase (AST) were determined by biochemical analyzer. 90% reference intervals were calculated for all parameters.

Results: The hematological and serum biochemical profiles of indigenous sheep showed wide range and variation. The results were categorized according to sex and age of the sheep for comparison. Young sheep had significantly higher PCV, eosinophil, triglyceride, and TP level than that of adult (p<0.05), whereas the urea and albumin level was higher in adult than that of juvenile (p<0.05). Most of the values of the parameters are close to each other for both male and female except TEC, urea, cholesterol, triglyceride, glucose, and AST. However, a significant difference was found only for albumin and basophil level between male and female sheep.

Conclusions: Hematological and biochemical parameters in Bangladeshi indigenous sheep showed a wide range and variation implicating future study for the prophylaxis of ovine diseases.

Keywords: Bangladesh, biochemical parameters, hematology, indigenous sheep, Ovis aries, reference values.

Antimicrobial resistance genes in pathogenic Escherichia coli isolated from diseased broiler chickens in Egypt and their relationship with the phenotypic resistance characteristics

Research (Published online: 09-08-2018)

10. Antimicrobial resistance genes in pathogenic Escherichia coli isolated from diseased broiler chickens in Egypt and their relationship with the phenotypic resistance characteristics

Mohamed M. Amer, Hoda M. Mekky, Aziza M. Amer and Hanaa S. Fedawy

Veterinary World, 11(8): 1082-1088

Aim: The aim of this study was to determine the relationship between phenotypic resistance and genotypic resistance of isolated serotyped pathogenic Escherichia coli isolates from the clinically diseased broiler.

Materials and Methods: A total of 160 samples (heart, liver, kidney, and lung) were collected from 18 to 34 days old clinically diseased broiler from 40 broiler farms (3-5 birds/farm) reared in Giza and Kaluobaia Governorates for the isolation of pathogenic E. coli. Various E. coli isolates were tested for the pathogenicity based on Congo red (CR) dye binding assay. The obtained CR-positive E. coli isolates were subjected to serological identification using slide agglutination test. Disc diffusion test was used to study the sensitivity pattern of E. coli isolates to available 12 antibiotics. Polymerase chain reaction was performed for the detection of antimicrobial resistance genes in the studied pathogenic E. coli isolates.

Results: The results revealed that 56 samples (35 %) were positive for E. coli. The results of the CR assay indicates that 20 isolates of 56 (35.7%) were positive and 36 isolates (64.3%) were negative. Identified E. coliserotypes of CR-positive isolates were 1 (O24), 2 (O44), 2 (O55), 5 (O78), 2 (O86), 1 (124), 3 (O127), 1 (O158), and 3 untyped. Resistance rate in disc diffusion test was 85% to oxytetracycline and kanamycin; 80% to ampicillin (AMP), clindamycin, and streptomycin (S); 75% to enrofloxacin; 65% to chloramphenicol; 55% to cefotaxime and gentamicin (CN); 45% to trimethoprim+sulfamethoxazole; 35% to erythromycin (ERI); and 30% to oxacillin. All strains are multidrug-resistant (MDR). Antibacterial resistance genes CITM, ere, aac (3)-(IV), tet(A), tet(B), dfr(A1), and aad(A1) were detected in 14 (70%), 12 (60%), 12 (60%), 8 (40%), 11 (55%), 8 (40%), and 9 (45%) of tested 20 isolates, respectively. Multidrug resistance was detected in the form of resistance to 42%-83.3% of tested 12 antibiotics. Three isolates (15%) of 20 tested isolates showed a relationship between phenotype and genotype and 17 (85%) showed irregular relation. Strains are sensitive and show resistant gene (P-G+) presented in three isolates for AMP (beta-lactam), one for ERI (Macrolide), as well as five isolates for trimethoprim (pyrimidine inhibitor). E. coli isolates had resistance and lacked gene (P+ G-) reported meanly in one isolate for CN (aminoglycoside), two isolates for tetracycline, four isolates for ERI, seven isolates for trimethoprim, and eight isolates for S (aminoglycoside).

Conclusions: The study demonstrates that E. coli is still a major pathogen responsible for disease conditions in broiler. E. coli isolates are pathogenic and MDR. Responsible gene was detected for six antibiotics in most of the isolates, but some do not show gene expression, this may be due to few numbers of resistance genes tested or other resistance factors not included in this study.

Keywords: antibiotic resistance genes, broiler, Escherichia coli, isolation.

Sources of contamination, prevalence, and antimicrobial resistance of thermophilic Campylobacterisolated from turkeys

Research (Published online: 07-08-2018)

9. Sources of contamination, prevalence, and antimicrobial resistance of thermophilic Campylobacterisolated from turkeys

Radia Bouhamed, Leila Bouayad, Sara Messad, Safia Zenia, Malek Naim and Taha-Mossadak Hamdi

Veterinary World, 11(8): 1074-1081

ABSTRACT

Aim: Sources of contamination, prevalence, and antimicrobial susceptibility of thermophilic Campylobacter isolated from turkey samples were determined.

Materials and Methods: A total of 300 samples were collected from 3 farms (fecal droppings) and 4 poultry slaughterhouses (neck skins and ceca) located in the middle area of Algeria (Algiers, Boumerdes, and Bouira). After detection, an antibiogram was realized only for slaughterhouses samples.

Results: Samples from cecum (90.0%, 90/100; 95% confidence interval (CI)=84.1-95.9%), fecal dropping (68.0%, 68/100; 95% CI=58.9-77.1%), and neck skin (55.0%, 55/100; 95% CI=45.2-64.8%) were positive for thermophilic Campylobacter (p<0.05). Contamination rate of turkey carcasses was higher in modern slaughterhouse (96.7%) than in traditional slaughterhouses (37.1%) (p<0.05). Isolated strains were resistant to nalidixic acid (NA) (87.5%), tetracycline (TE) (81.3%), ciprofloxacin (CIP) (75.0%), ampicillin (AM) (65.6%), and erythromycin (25.0%) (p<0.05). 96.9% (124/128) of the isolates were multiresistant and 18 drug resistance patterns were registered. The predominant one (43.0%) was AM, NA, CIP, and TE.

Conclusions: Potential sources of contamination of this fastidious bacterium were noticed in farms and slaughterhouses. Modern slaughterhouse allowed contamination of turkey carcasses more than a traditional slaughterhouse. However, the scalding step could not represent a source of contamination. The most tested strains exhibited resistance to erythromycin and/or CIP. It is worrisome because these molecules are considered as first-choice antibiotics for human campylobacteriosis.

Keywords: antimicrobial resistance, farm, slaughterhouse, Thermophilic Campylobacter, turkey.

Effectiveness of poultry litter amendments on bacterial survival and Eimeria oocyst sporulation

Research (Published online: 06-08-2018)

8. Effectiveness of poultry litter amendments on bacterial survival and Eimeria oocyst sporulation

Essam S. Soliman, Nahla H. Sallam and Eman M. Abouelhassan

Veterinary World, 11(8): 1064-1073

ABSTRACT

Aim: Broilers' optimum performance in response to their genetic potential depends on litter environment which is ideal for bacterial survival and coccidian oocyst sporulation. An in vitro evaluation was conducted for the effectiveness of superphosphate, meta-bisulfide, and charcoal litter amendments in minimizing Escherichia coli O157:H7 and Salmonella Typhimurium survival, Eimeria oocyst count, and sporulation.

Materials and Methods: Three groups of 16 litter trays were prepared and inoculated with E. coli O157:H7, S. Typhimurium, and Eimeria non-sporulated oocyst. A set of four trays in each group was designed for each one of the chemical amendments. A total of 720 litter samples were collected and examined for bacterial counts, Eimeria oocyst count, and sporulation during the experimental period (35 days).

Results: Litter moisture and pH revealed a highly significant (p<0.001) reduction in all treated litter trays compared to control. Total bacterial count (TBC), total Enterobacteriaceae count, and S. Typhimurium count showed a highly significant (p<0.001) reduction in meta-bisulfide-treated trays compared to other amendments and positive control. Meanwhile, Eimeria oocyst count and sporulation revealed a highly significant (p<0.001) reduction in superphosphate, meta-bisulfide, and charcoal-treated trays, respectively. Temperature revealed a highly significant (p<0.001) weak positive correlation with pH of all inoculated trays, a highly significant (p<0.001) weak negative correlation with moisture percentage of E. coli O157:H7 and S. Typhimurium inoculated trays, and a highly significant (p<0.001) weak negative correlation with TBC. Meanwhile, relative humidity revealed significant (p≤0.005) weak positive correlation with moisture percentage of E. coli O157:H7 inoculated trays.

Conclusion: The study concluded that regular usage with periodical reapplication of litter amendments as meta-bisulfide or superphosphate in poultry farms is one of the indispensable managemental and preventive measures for minimizing bacterial survival and inhibiting Eimeria oocyst maturation and sporulation.

Keywords: charcoal, Eimeria, Escherichia coli, litter, meta-bisulfide, Salmonella, superphosphate.