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Prion protein genotypes of sheep as determined from 3343 samples submitted from Ontario and other provinces of Canada from 2005 to 2012
2014
Cameron, Colin | Bell-Rogers, Patricia | McDowall, Rebeccah | Rebelo, Ana R. | Cai, Hugh Y.
This study analyzed sheep prion protein (PrP) genotypes of samples submitted from Ontario and other provinces of Canada to the Animal Health Laboratory at the University of Guelph, Guelph, Ontario, between 2005 and 2012. In Ontario, the proportion of scrapie-resistant sheep increased from 2005 to 2012 as evidenced by an increase in the ARR haplotype. When Canadian provinces (Alberta, Ontario, Quebec, and Nova Scotia) were compared from 2008 to 2012, a high proportion of scrapie-resistant sheep was found in all the provinces. The proportions of resistant sheep were lower in Alberta and Quebec than in Ontario and Nova Scotia. Alberta had higher proportions of susceptible sheep and a higher frequency of VRQ alleles, and Quebec had a higher frequency of the ARQ allele.
اظهر المزيد [+] اقل [-]Rapid detection of Streptococcus suis serotype 2 in weaned pigs
1989
Moreau, A. | Higgins, R. | Bigras-Poulin, M. | Nadeau, M.
A survey to detect Streptococcus suis serotype 2 in 1,716 weaned pigs was done in Quebec. Forty-nine sow herds were included in this survey: in 26 herds, S suis serotype 2 had been isolated during the preceding 12 months and in 23 herds (control), the organism had not been detected during a previous study. Swab specimens of the nasal cavity and tonsils of pigs were obtained for bacteriological culture, and S suis serotype 2 was easily detected by the use of brain-heart infusion agar containing a Streptococcus-selective supplement and 5% goat antiserum raised against S suis serotype 2. After measurement of the diameter of the precipitation zone of 539 isolates, a slide agglutination test was performed to identify the S suis serot ype 2 isolates. The mean precipitation zone diameter obtained for group S suis serotype 2 was larger (P less than 0.001) than that for the group designated as "others." With slide agglutination test results as reference and on the basis of discriminant analysis to simulate detection of S suis serotype 2, 93.1% of all isolates were correctly classified, using the precipitation zone diameter as unique classification criterion. Relative specificity was 94.5% and relative sensitivity was 88.7%. Use of the precipitation zone diameter on a quantitative basis led to the proposal of a simple and reliable technique to screen swine herds for S suis serotype 2 in weaned pigs. Nasal and tonsillar swab specimens were obtained and analyzed concurrently for S suis serotype 2. The organism was found in both sites in only 20.4% of 103 carrier pigs. Nasal and tonsillar specimens yielded 55.3 and 65%, respectively, of all S suis serotype 2 isolates. Statistically significant difference was not observed between the numbers of S suis serotype 2 isolated from each site. Both sites permitted the recovery of S suis serotype 2 isolates; it was advantageous to use nasal and tonsillar swab specimens to determine the most reliable evaluation of S suis serotype-2 carrier status in weaned pigs.
اظهر المزيد [+] اقل [-]Prevalence and risk factors for Campylobacter spp., Salmonella spp., Coxiella burnetii, and Newcastle disease virus in feral pigeons (Columba livia) in public areas of Montreal, Canada
2016
Gabriele-Rivet, Vanessa | Fairbrother, Julie-Helene | Tremblay, Donald | Harel, Josee | Cote, Nathalie | Arsenault, Julie
Feral pigeons (Columbia livia) can harbor a range of zoonotic pathogens. A transversal study was undertaken to estimate the prevalence of feral pigeons infected by various pathogens in public areas in Montreal, Quebec. Cloacal swabs from captured birds were cultured for Salmonella spp. and Campylobacter spp. and tested by real-time polymerase chain reaction (RT-PCR) for the detection of Coxiella burnetii. An oropharyngeal swab was also submitted to real-time reverse-transcription polymerase chain reaction (RRT-PCR) for the detection of Newcastle disease virus. Among the 187 pigeons tested from 10 public areas, 9.1% (95% CI: 3.0 to 15.2) were positive for Campylobacter spp. with all strains identified as Campylobacter jejuni. The Campylobacter status of birds was not associated with individual characteristics of birds, with the exception of body score. None of the pigeons tested positive for the other pathogens. Direct or indirect contacts with feral pigeons may constitute a potential risk for Campylobacter infection in humans.
اظهر المزيد [+] اقل [-]Presence and characterization of Campylobacter jejuni in organically raised chickens in Quebec
2011
Thibodeau, Alexandre | Fravalo, Philippe | Laurent-Lewandowski, Sylvette | Guévremont, Evelyne | Quessy, Sylvain | Letellier, Ann
The objective of this study was to estimate the presence of the important foodborne pathogen Campylobacter jejuni in organically raised chickens in the province of Quebec. The recovered isolates were further characterized for their antimicrobial resistance profile, autoagglutination property and chemotaxis. Antimicrobial resistance was evaluated using agar dilution for: tetracycline, erythromycin, chloramphenicol, ciprofloxacin, gentamicin, nalidixic acid, clindamycin, ampicillin, azithromycin, bacitracin, and ceftiofur. Autoagglutination was measured by monitoring optical density changes in a bacterial suspension after 3 h of incubation at room temperature. Chemotaxis was evaluated after a contact time of 3 h between isolates and mucin, using a quantitative protocol. A total of 10 lots of chickens was sampled in August and September 2009; half of them were positive for the presence of C. jejuni. Antimicrobial resistance was found only for tetracycline (44%), erythromycin (6%), azithromycin (6%) and clindamycin (2%). Variation was observed in the minimum inhibitory concentrations (MICs) for ceftiofur and bacitracin, for which C. jejuni possess intrinsic resistance. Autoagglutination and chemotaxis varied among isolates and lot-level differences in these were observed. Autoagglutination and chemotaxis levels appeared as independent isolate properties. Further monitoring and characterization of isolates originating from organic chickens is of interest since this type of production might represent another source of exposure of consumers to a variety of the foodborne pathogen C. jejuni.
اظهر المزيد [+] اقل [-]Beekeeping management practices in southwestern Quebec
2021
The growing number of honey bee colonies and beekeepers in Canada has led to a great diversity of beekeeping practices. All beekeeping operations, however, need to implement consistent management measures for the control of diseases. The objective of this study was to document the actual disease management practices of beekeeping productions in southwestern Quebec, Canada. A survey was conducted to describe management practices used by 15 beekeepers who own 1824 colonies in that area. Data were obtained by telephone interviews. When infectious diseases were suspected, beekeepers generally avoided using potentially toxic acaricides and chemical treatments associated with antimicrobial resistance and instead used preventive, physical or management methods, although laboratory diagnosis was rarely used. This study highlights the wide variety of operation sizes, activities, and disease management strategies among beekeepers in southwestern Quebec. It identifies the need to encourage the use of services available to them and to propose a standardized preventive medical approach for field veterinarians to avoid the spread of infectious diseases.
اظهر المزيد [+] اقل [-]Impact of a trap-neuter-return event on the size of free-roaming cat colonies around barns and stables in Quebec: A randomized controlled trial
2018
Bissonnette, V. | Lussier, B. | Doize, B. | Arsenault, J.
The objective of this study was to evaluate the impact of a trap-neuter-return (TNR) event on the size of free-roaming rural cat colonies in Quebec. This prospective randomized, controlled study included 18 cat colonies around barns and stables that were randomly assigned to either a TNR group (10 colonies of 7 to 27 cats; 14.3 cats on average) or a control group (8 colonies of 7 to 26 cats; 14.5 cats on average). The number of cats in each colony was calculated from the images obtained by camera-trapping at: baseline (T0), 7.5 mo (T7), and 12 mo (T12). At baseline, the TNR group was subjected to a TNR event. When taking into account adults only, a significant growth difference was observed in the number of cats between the TNR group and the control group at T7 (P = 0.03). When including kittens as well as adults, a trend towards a lower growth of the TNR group compared to the control group was noted at T7 (P = 0.06). There was no difference in the number of kittens between the 2 groups at T7 (P = 0.49) or at T12 (P = 0.36). There was a trend towards more emigration in the control group at T12 (P = 0.095). Isolated TNR events have a low and temporary impact on colony size in Quebec's rural cat colonies.
اظهر المزيد [+] اقل [-]Porcine reproductive and respiratory syndrome virus (PRRSV) in pig meat
2017
Raymond, Philippe | Bellehumeur, Christian | Nagarajan, Malliga | Longtin, Diane | Ferland, Alexandra | Müller, Peter | Bissonnette, Rachel | Simard, Carole
rcine reproductive and respiratory syndrome, caused by the porcine reproductive and respiratory syndrome virus (PRRSV), is an economically important disease in the swine industry. Previous studies demonstrated the presence of the virus in pig meat and its transmissibility by oral consumption. This study further analyzed the infectivity of PRRSV in commercial pig meat. Fresh bottom meat pieces (n = 1500) randomly selected over a period of 2 y from a pork ham boning plant located in Quebec, Canada, were tested by reverse transcriptase polymerase chain reaction (RT-PCR). Each trimmed meat was stored in the plant freezer, subsampled weekly for up to 15 wk, and tested with quantitative RT-PCR to determine the viral load. Meat infectivity was evaluated using specific pathogen-free piglets, each fed with approximately 500 g of meat at the end of the storage time. Genotype-specific RT-PCR confirmed the presence of PRRSV mainly during cold weather in 0.73% of the fresh meat pieces. Wild and vaccine strains of genotype 2 were detected. Porcine reproductive and respiratory syndrome virus nucleic acid was stable in meat stored at around -20°C during the 15 wk. Serological and molecular analysis showed the transmission of infection by a majority of PRRSV positive meat pieces (5/9) fed orally to naïve recipients. The results confirmed a low prevalence of PRRSV in market's pig meat, and virus transmissibility by oral consumption to naïve recipients even after several weeks of storage in a commercial freezer. It occurred mainly with meat harboring the highest PRRSV RNA copies, in the range of 109 copies per 500 g of meat, with both wild type and vaccine-related strains.
اظهر المزيد [+] اقل [-]Drug use and antimicrobial resistance among Escherichia coli and Enterococcus spp. isolates from chicken and turkey flocks slaughtered in Quebec, Canada
2016
Boulianne, M. (Martine) | Arsenault, Julie | Daignault, Danielle | Archambault, Marie | Letellier, Ann | Dutil, Lucie
An observational study was conducted of chicken and turkey flocks slaughtered at federal processing plants in the province of Quebec, Canada. The objectives were to estimate prevalence of drug use at hatchery and on farm and to identify antimicrobial resistance (AMR) in cecal Escherichia coli and Enterococcus spp. isolates and factors associated with AMR. Eighty-two chicken flocks and 59 turkey flocks were sampled. At the hatchery, the most used antimicrobial was ceftiofur in chickens (76% of flocks) and spectinomycin in turkeys (42% of flocks). Virginiamycin was the antimicrobial most frequently added to the feed in both chicken and turkey flocks. At least 1 E. coli isolate resistant to third-generation cephalosporins was present in all chicken flocks and in a third of turkey flocks. Resistance to tetracycline, streptomycin, and sulfisoxazole was detected in > 90% of flocks for E. coli isolates. Antimicrobial resistance (AMR) was observed to bacitracin, erythromycin, lincomycin, quinupristin-dalfopristin, and tetracycline in both chicken and turkey flocks for Enterococcus spp. isolates. No resistance to vancomycin was observed. The use of ceftiofur at hatchery was significantly associated with the proportion of ceftiofur-resistant E. coli isolates in chicken flocks. In turkey flocks, ceftiofur resistance was more frequent when turkeys were placed on litter previously used by chickens. Associations between drug use and resistance were observed with tetracycline (turkey) in E. coli isolates and with bacitracin (chicken and turkey), gentamicin (turkey), and tylosin (chicken) in Enterococcus spp. isolates. Further studies are needed to provide producers and veterinarians with alternative management practices and tools in order to reduce the use of antimicrobial feed additives in poultry.
اظهر المزيد [+] اقل [-]Effect of reproductive disorders and parity on repeat breeder status and culling of dairy cows in Quebec
2011
Bonneville-Hébert, Ariane | Bouchard, Emile | Du Tremblay, Denis | Lefebvre, Réjean
This study quantified the effect of peripartum reproductive disorders and parity on repeat breeder status and involuntary culling of dairy cows. Reproductive data of 418 383 lactations were taken from a computerized databank of health records for dairy cows. A logistic regression model was used with dystocia, retained placenta (RP), metritis complex, and parity as fixed effect risk factors and herd entered as the random effect. Of the peripartum problems studied, dystocia had the greatest effect on future fertility. Dystocia increased the odds of a cow being a repeat breeder by 44% [odds ratio (OR): 1.44; confidence interval (CI): 1.37 to 1.51]. Compared to first-parity cows, cows in second, third, and fourth parities had significantly higher odds of being a repeat breeder: 18% (OR: 1.18; CI: 1.16 to 1.20); 24% (OR: 1.24; CI: 1.21 to 1.26); and 42% (OR: 1.42; CI: 1.39 to 1.45), respectively. The odds for second-, third-, or fourth-parity repeat breeders being culled were 24% (OR: 1.24; CI: 1.20 to 1.28); 39% (OR: 1.39; CI: 1.35 to 1.43); and 67% (OR: 1.67; CI: 1.62 to 1.71) respectively, while peripartum reproductive problems had less of an effect.
اظهر المزيد [+] اقل [-]Comparative serologic and virologic study of commercial swine herds with and without postweaning multisystemic wasting syndrome
2003
Larochelle, Renée | Magar, Ronald | D'Allaire, Sylvie
A comparative serologic and virologic study was performed in pigs from 5 herds with postweaning multisystemic wasting syndrome (PMWS) and 2 herds without PMWS in Quebec. In each herd, 60 blood samples were collected at 4-wk intervals from pigs from 3 to 23 wk of age. The serum was evaluated for the presence of antibodies to porcine circovirus type 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV), as well as for the presence of nucleic acid of PCV2, PRRSV, and porcine parvovirus (PPV), by means of the polymerase chain reaction (PCR). Serologic profiles for PCV2 were very similar in 6 of the 7 herds, including the 2 without PMWS, and were characterized by a gradual decrease in antibody titres from 3 until 11 wk of age, followed by seroconversion at 15 wk, and high PCV2 antibody titres thereafter in all pigs. Only starting at 11 to 15 wk of age could PCV2 viremia be detected, except in 1 herd, in which clinical signs were observed at 6 to 7 wk of age. A PCV2 viremia could be detected within the same pigs for a minimum of 8 wk, and the virus could still be detected in 41% of the serum samples obtained at 23 wk of age. The antibody level did not appear to influence the occurrence of disease, since titres were similar in pigs in the herds with or without PMWS. Infection with PRRSV, as demonstrated by PCR and seroconversion, preceded that of PCV2 by at least 1 mo in both types of herd. Both PRRSV and PCV2 were detected in some pigs in 5 of the 7 herds, including 1 herd without PMWS. Porcine parvovirus could be detected in serum by PCR in 2 herds with PMWS after the onset of clinical signs and also in 1 herd without PMWS. Genomic analysis of PCV2 strains identified in the herds without PMWS indicated complete or very high homology (99.4% to 100%) with the PCV2 strains identified in 4 herds with PMWS. In our field study, the triggering of PMWS in the herds could not be linked to coinfection with either PRRSV or PPV or to the use of a specific immunostimulant, such as vaccines, or to particular genomic differences between the PCV2 strains identified.
اظهر المزيد [+] اقل [-]