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Background Respiratory diseases are among the most important factors affecting swine farm productivity in Canada. The objectives of this study were to investigate antibody responses to porcine reproductive and respiratory syndrome virus (PRRSV), influenza A virus (IAV), and Mycoplasma hyopneumoniae (M. hyopneumoniae) from weaning to the end of the finisher stage on a subset of commercial swine farms in Ontario, Canada, and to examine the association between nursery diet and antibody responses. Results Overall, older pigs were more likely to test seropositive for PRRSV and less likely to test seropositive for M. hyopneumoniae (p < 0.001). Pigs were more likely to test seropositive for IAV at weaning and the end of the grower and finisher stages compared to the end of nursery (p < 0.001). Pigs that were seropositive for IAV were more likely to test seropositive for both PRRSV and M. hyopneumoniae (p < 0.001). Two, 9, and 4 groups that had more than 20% of pigs seropositive to PRRSV, IAV, and M. hyopneumoniae, respectively, from the end of nursery to the end of finisher were classified as seropositive. Pigs fed a plant-based (low complexity) diet during nursery were more likely to be seropositive for PRRSV (p < 0.001) but there were no significant differences in seropositivity to IAV or M. hyopneumoniae due to nursery diet complexity. Conclusions This study provides information regarding changes in serum antibody in pigs across different stages of production and highlights periods of vulnerability. Additionally, these findings may encourage further research into the effects of nursery diet complexity on disease susceptibility and immune response.
Elana Raaphorst; Abdolvahab Farzan; Robert M. Friendship; Brandon N. Lillie. Antibody responses to porcine reproductive and respiratory syndrome virus, influenza A virus, and Mycoplasma hyopneumoniae from weaning to the end of the finisher stage in fourteen groups of pigs in Ontario, Canada. BMC Veterinary Research 2021, 17, 1 -11.
AMA StyleElana Raaphorst, Abdolvahab Farzan, Robert M. Friendship, Brandon N. Lillie. Antibody responses to porcine reproductive and respiratory syndrome virus, influenza A virus, and Mycoplasma hyopneumoniae from weaning to the end of the finisher stage in fourteen groups of pigs in Ontario, Canada. BMC Veterinary Research. 2021; 17 (1):1-11.
Chicago/Turabian StyleElana Raaphorst; Abdolvahab Farzan; Robert M. Friendship; Brandon N. Lillie. 2021. "Antibody responses to porcine reproductive and respiratory syndrome virus, influenza A virus, and Mycoplasma hyopneumoniae from weaning to the end of the finisher stage in fourteen groups of pigs in Ontario, Canada." BMC Veterinary Research 17, no. 1: 1-11.
The objectives of this study were: to identify nursery cohorts with an active Salmonella infection using combined serological and bacteriological methods, and to try to identify risk factors associated with swine nurseries with active Salmonella spread. Twenty pigs from each of 50 cohorts of weaned pigs from 44 different nursery barns were sampled about the time of weaning and near the end of the nursery stage. Information regarding farm management and biosecurity practices were collected using a questionnaire. Blood samples were obtained at both visits, while rectal swabs were collected at the second visit. An enzyme-linked immunosorbent assay (ELISA) was used to test sera for Salmonella antibodies and rectal samples were cultured for Salmonella. A nursery cohort was identified as having an active Salmonella infection if Salmonella was cultured from one or more of the 20 pigs or if serological evidence suggested exposure to Salmonella. The association between farm-level management covariates and active Salmonella infection was assessed in 46 cohorts using a logistic regression model. Nine of 46 (20%) cohorts produced Salmonella-free pigs. The remaining 37 (80%) cohorts were classified as having an active infection. Examination of risk factors failed to identify how negative and positive nurseries differed.
Saranya Nair; Abdolvahab Farzan; Zvonimir Poljak; Robert Friendship. Identifying Active Salmonella Infections in Swine Nurseries Using Serology and Bacterial Culture and Evaluating Associated Risk Factors. Animals 2020, 10, 1517 .
AMA StyleSaranya Nair, Abdolvahab Farzan, Zvonimir Poljak, Robert Friendship. Identifying Active Salmonella Infections in Swine Nurseries Using Serology and Bacterial Culture and Evaluating Associated Risk Factors. Animals. 2020; 10 (9):1517.
Chicago/Turabian StyleSaranya Nair; Abdolvahab Farzan; Zvonimir Poljak; Robert Friendship. 2020. "Identifying Active Salmonella Infections in Swine Nurseries Using Serology and Bacterial Culture and Evaluating Associated Risk Factors." Animals 10, no. 9: 1517.
Background The heightened prevalence of Salmonella Typhimurium remains a public health and food safety concern. Studies have reported antibiotic, flavophospholipol, may have the ability to reduce Salmonella in swine, as well as alter the gut microbiota in favour of beneficial bacteria by inhibiting pathogenic bacteria. Thus, the objective of this study was to investigate the fecal microbiota of weaned pigs receiving in-feed flavophospholipol and challenged with Salmonella Typhimurium. Results Twenty-one weaned pigs were fed either a diet containing 4 ppm of flavophospholipol (treatment group) or a non-medicated feed (control group) for 36 days post-weaning (Day 1 to Day 36). The pigs were orally challenged with a 2 mL dose of 10 8 CFU/mL of S. Typhimurium at Day 7 and Day 8. Community bacterial DNA extracted from fecal samples collected at Day 6 (before challenge) and Day 36 (28 days after challenge) were used to assess the fecal microbiota using the V4 region of the 16S rRNA gene with Illumina MiSeq next-generation sequencing. Sequencing data were visualized using mothur and analyzed in JMP and R software. The fecal microbiota of pigs in the treatment group had differences in abundance of phyla (Firmicutes, Proteobacteria) and genera ( Lactobacillus, Roseburia , Treponema, unclassified Ruminococcaceae, Blautia , Streptococcus , Megasphaera , Dorea , Sporobacter , Peptococcus , unclassified Firmicutes, Clostridium IV and Campylobacter) when compared to pigs that were controls, 28 days after challenge with Salmonella ( P
Saranya Nair; Vahab Farzan; J Scott Weese; Zvonimir Poljak; Robert M Friendship. Effect of flavophospholipol on fecal microbiota in weaned pigs challenged with Salmonella Typhimurium. 2020, 1 .
AMA StyleSaranya Nair, Vahab Farzan, J Scott Weese, Zvonimir Poljak, Robert M Friendship. Effect of flavophospholipol on fecal microbiota in weaned pigs challenged with Salmonella Typhimurium. . 2020; ():1.
Chicago/Turabian StyleSaranya Nair; Vahab Farzan; J Scott Weese; Zvonimir Poljak; Robert M Friendship. 2020. "Effect of flavophospholipol on fecal microbiota in weaned pigs challenged with Salmonella Typhimurium." , no. : 1.
Background The heightened prevalence of Salmonella Typhimurium remains a public health and food safety concern. Studies have reported antibiotic, flavophospholipol, may have the ability to reduce Salmonella in swine, as well as alter the gut microbiota in favour of beneficial bacteria by inhibiting pathogenic bacteria. Thus, the objective of this study was to investigate the fecal microbiota of weaned pigs receiving in-feed flavophospholipol and challenged with Salmonella Typhimurium.Results Twenty-one weaned pigs were fed either a diet containing 4 ppm of flavophospholipol (treatment group) or a non-medicated feed (control group) for 36 days post-weaning (Day 1 to Day 36). The pigs were orally challenged with a 2 mL dose of 108 CFU/mL of S. Typhimurium at Day 7 and Day 8. Community bacterial DNA extracted from fecal samples collected at Day 6 (before challenge) and Day 36 (28 days after challenge) were used to assess the fecal microbiota using the V4 region of the 16S rRNA gene with Illumina MiSeq next-generation sequencing. Sequencing data were visualized using mothur and analyzed in JMP and R software. The fecal microbiota of pigs in the treatment group had differences in abundance of phyla (Firmicutes, Proteobacteria) and genera (Lactobacillus, Roseburia, Treponema, unclassified Ruminococcaceae, Blautia, Streptococcus, Megasphaera, Dorea, Sporobacter, Peptococcus, unclassified Firmicutes, Clostridium IV and Campylobacter) when compared to pigs that were controls, 28 days after challenge with Salmonella (P
Saranya Nair; Vahab Farzan; J Scott Weese; Zvonimir Poljak; Robert M Friendship. Effect of flavophospholipol on fecal microbiota in weaned pigs challenged with Salmonella Typhimurium. 2020, 1 .
AMA StyleSaranya Nair, Vahab Farzan, J Scott Weese, Zvonimir Poljak, Robert M Friendship. Effect of flavophospholipol on fecal microbiota in weaned pigs challenged with Salmonella Typhimurium. . 2020; ():1.
Chicago/Turabian StyleSaranya Nair; Vahab Farzan; J Scott Weese; Zvonimir Poljak; Robert M Friendship. 2020. "Effect of flavophospholipol on fecal microbiota in weaned pigs challenged with Salmonella Typhimurium." , no. : 1.
Background Porcine reproductive and respiratory syndrome, swine influenza, and mycoplasmal pneumonia are some of the most prevalent respiratory diseases affecting swine farm productivity in Canada. Monitoring for the prevalence of the infectious agents associated with these diseases on farm may help to improve herd-specific control strategies and to minimize the impact of disease on commercial swine farms. The objectives of this study were to investigate antibody responses to porcine reproductive and respiratory syndrome virus (PRRSV), influenza A virus (IAV), and Mycoplasma hyopneumoniae ( M. hyopneumoniae ) from weaning to the end of the finisher stage on a subset of commercial swine farms in Ontario and to examine the effects of nursery diet on antibody responses. Results Serology found 8, 61, and 31% of pigs at weaning, 1, 31, and 22% at the end of nursery, 8, 38, and 18% at the end of grower, and 11, 48, and 25% at the end of the finisher stage tested seropositive for PRRSV, IAV, and M. hyopneumoniae, respectively. Of the groups tested for PRRSV, IAV, and M. hyopneumoniae, 3, 14, and 5 groups had > 20% of pigs that tested seropositive at least once over the course of production (“high seropositivity”). In general, seropositivity was more likely to be lower at the end of nursery compared to the other production stages for all three pathogens, and more likely to be higher for PRRSV and IAV at weaning, end of grower, and end of finisher. Pigs that were seropositive for PRRSV were more likely to be seropositive forM. hyopneumoniae (p < 0.001). Overall, pigs fed a low complexity diet during nursery were more likely to be seropositive for PRRSV (p < 0.001) and IAV (p = 0.04). Conclusions This study provides information regarding changes in serum antibody in pigs across different stages of production and highlights periods of vulnerability. Additionally, these findings may encourage further research into the effects of nursery diet complexity on disease susceptibility and immune response.
Elana Raaphorst; Abdolvahab Farzan; Robert M. Friendship; Brandon N. Lillie. Antibody responses to porcine reproductive and respiratory syndrome virus, influenza A virus, and Mycoplasma hyopneumoniae from weaning to the end of the finisher stage in fourteen groups of pigs in Ontario. 2020, 1 .
AMA StyleElana Raaphorst, Abdolvahab Farzan, Robert M. Friendship, Brandon N. Lillie. Antibody responses to porcine reproductive and respiratory syndrome virus, influenza A virus, and Mycoplasma hyopneumoniae from weaning to the end of the finisher stage in fourteen groups of pigs in Ontario. . 2020; ():1.
Chicago/Turabian StyleElana Raaphorst; Abdolvahab Farzan; Robert M. Friendship; Brandon N. Lillie. 2020. "Antibody responses to porcine reproductive and respiratory syndrome virus, influenza A virus, and Mycoplasma hyopneumoniae from weaning to the end of the finisher stage in fourteen groups of pigs in Ontario." , no. : 1.
Streptococcus suis naturally inhabits the tonsils and nasal cavities of pigs. Some strains can cause systemic infection, leading to a wide range of diseases. A case-control study was conducted to (i) examine serotypes isolated from systemic sites (blood/meninges/spleen) in cases, (ii) determine whether serotypes in systemic sites were found in upper respiratory sites (tonsil/nasal cavity) of the same cases, and (iii) determine the serotypes in upper respiratory sites of case and farm and pen- matched controls. In total, 606 samples from 128 pigs were cultured for S. suis. The isolates were examined for presence of gdh and recN genes by polymerase chain reaction (PCR) and were identified as S. suis if both genes were present. The S. suis isolates were then serotyped using a two step-multiplex PCR. Serotypes 9 (n = 9), (2,1/2) (n = 7) and untypable isolates (n = 7) were most commonly found in systemic sites. Detection of serotypes 9 (p = 0.03) in upper respiratory sites were positively associated with their detection in systemic sites of cases, while a trend was seen with serotype (2,1/2) (p = 0.07). Last, no association between serotypes recovered from upper respiratory sites of cases and controls could be detected. Untypable isolates were detected in high frequency, which warrants further investigation. This study confirms that a variety of serotypes can be found in commercial swine production and shows a difference in serotypes recovered from systemic sites in pigs with clinical signs of S. suis infections.
LeAnn C. Denich; Abdolvahab Farzan; Robert Friendship; Emily Arndt; Marcelo Gottschalk; Zvonimir Poljak. A Case-Control Study to Investigate the Serotypes of S. suis Isolates by Multiplex PCR in Nursery Pigs in Ontario, Canada. Pathogens 2020, 9, 44 .
AMA StyleLeAnn C. Denich, Abdolvahab Farzan, Robert Friendship, Emily Arndt, Marcelo Gottschalk, Zvonimir Poljak. A Case-Control Study to Investigate the Serotypes of S. suis Isolates by Multiplex PCR in Nursery Pigs in Ontario, Canada. Pathogens. 2020; 9 (1):44.
Chicago/Turabian StyleLeAnn C. Denich; Abdolvahab Farzan; Robert Friendship; Emily Arndt; Marcelo Gottschalk; Zvonimir Poljak. 2020. "A Case-Control Study to Investigate the Serotypes of S. suis Isolates by Multiplex PCR in Nursery Pigs in Ontario, Canada." Pathogens 9, no. 1: 44.
Background The heightened prevalence of Salmonella Typhimurium in nursery pigs remains a public health and food safety concern. Studies have reported antibiotic, flavophospholipol, may have the ability to reduce Salmonella in swine, as well as alter the gut microbiota in favour of beneficial bacteria by inhibiting pathogenic bacteria. Thus, the objective of this study was to investigate the fecal microbiota of weaned pigs receiving in-feed flavophospholipol and challenged with Salmonella Typhimurium. Results Twenty-one weaned pigs were fed either a diet containing 4 ppm of flavophospholipol (treatment group) or a non-medicated feed (control group) for 36 days post-weaning (Day 1 to Day 36). The pigs were orally challenged with a 2 mL dose of 10 8 CFU/mL of S. Typhimurium at Day 7 and Day 8. Community bacterial DNA extracted from fecal samples collected at Day 6 (before challenge) and Day 36 (28 days after challenge) were used to assess the fecal microbiota using the V4 region of the 16S rRNA gene with Illumina MiSeq next-generation sequencing. Sequencing data were visualized using mothur, and analyzed in JMP and R. The fecal microbiota of pigs in treatment group had significant differences in abundance of phyla (Firmicutes, Proteobacteria) and genera ( Lactobacillus, Roseburia , Treponema, unclassified Ruminococcaceae, Blautia , Streptococcus , Megasphaera , Dorea , Sporobacter , Peptococcus , unclassified Firmicutes, Clostridium IV and Campylobacter) when compared to pigs that controls 28 days after challenge with Salmonella ( P
Saranya Nair; Vahab Farzan; J Scott Weese; Zvonimir Poljak; Robert M Friendship. Effect of flavophospholipol on fecal microbiota in weaned pigs challenged with Salmonella Typhimurium. 2019, 1 .
AMA StyleSaranya Nair, Vahab Farzan, J Scott Weese, Zvonimir Poljak, Robert M Friendship. Effect of flavophospholipol on fecal microbiota in weaned pigs challenged with Salmonella Typhimurium. . 2019; ():1.
Chicago/Turabian StyleSaranya Nair; Vahab Farzan; J Scott Weese; Zvonimir Poljak; Robert M Friendship. 2019. "Effect of flavophospholipol on fecal microbiota in weaned pigs challenged with Salmonella Typhimurium." , no. : 1.
Salmonella is estimated to be one of the leading causes of enteric illness worldwide. Human salmonellosis is most frequently related to contaminated food products, particularly those of animal origin, such as pork. Pigs are often asymptomatic carriers of Salmonella, highlighting the importance of identifying high-prevalence farms and effective detection methods. The objectives of this study were to investigate Salmonella antibody responses and their association with on-farm shedding and Salmonella isolation at slaughter. Fourteen groups of pigs from eight farrowing sources were followed from birth to slaughter (totaling 796 pigs). Information about farm management was collected through a questionnaire. Blood and fecal samples were collected four times at different stages of production, and palatine tonsils/submandibular lymph nodes were obtained at slaughter. Sera were tested for Salmonella antibodies by enzyme-linked immunosorbent assay, and fecal/tissue samples were cultured for Salmonella. Data were analyzed using a mixed-effect multivariable modeling method with farm, litter, and pig as random effects. Salmonella seropositivity rates were 20.3%, 5.8%, 15.9%, and 37.3% at weaning, at the end of nursery, at end of grower, and at end of finisher, respectively. Salmonella seropositivity and shedding increased with age (p < 0.05), and pigs shedding Salmonella were more likely to test seropositive (p = 0.02). Antibody response and shedding on-farm had no significant association with isolation of Salmonella from tissues harvested at slaughter. The variation in Salmonella seropositivity due to farm was 28.9% of total variation. These findings indicate that on-farm intervention may be a more effective approach to control Salmonella and to reduce the presence of Salmonella at slaughter. Additionally, the observation that some pigs in this study were Salmonella-negative throughout production and at slaughter is promising with regard to food safety, and studies are needed to explore the genotypes of those pigs.
Corinne H. Schut; Abdolvahab Farzan; Margaret H. Ainslie-Garcia; Robert M. Friendship; Brandon N. Lillie. Antibody Responses to Salmonella in Pigs from Weaning Up to Marketing and Presence of Salmonella at Slaughter. Foodborne Pathogens and Disease 2019, 16, 187 -194.
AMA StyleCorinne H. Schut, Abdolvahab Farzan, Margaret H. Ainslie-Garcia, Robert M. Friendship, Brandon N. Lillie. Antibody Responses to Salmonella in Pigs from Weaning Up to Marketing and Presence of Salmonella at Slaughter. Foodborne Pathogens and Disease. 2019; 16 (3):187-194.
Chicago/Turabian StyleCorinne H. Schut; Abdolvahab Farzan; Margaret H. Ainslie-Garcia; Robert M. Friendship; Brandon N. Lillie. 2019. "Antibody Responses to Salmonella in Pigs from Weaning Up to Marketing and Presence of Salmonella at Slaughter." Foodborne Pathogens and Disease 16, no. 3: 187-194.
Foodborne human salmonellosis is an important food safety concern worldwide. Food-producing animals are one of the major sources of human salmonellosis, and thus control of Salmonella at the farm level could reduce Salmonella spread in the food supply system. Genetic selection of pigs with resistance to Salmonella infection may be one way to control Salmonella on swine farms. The objective of this study was to investigate the association between genetic variants in the porcine innate immune system with on-farm Salmonella shedding and Salmonella colonization tested at slaughter. Fourteen groups of pigs (total 809) were followed from birth to slaughter. Fecal samples collected five times at different stages of production and tissue samples obtained from tonsil and lymph nodes at slaughter were cultured for Salmonella. Genomic DNA was extracted and analyzed for 40 single nucleotide variants and two indels within porcine innate immune genes that were previously associated with Salmonella infection or other infectious diseases. A survey was used to collect information on farm management practices. A multilevel mixed-effects logistic regression modelling method was used to identify SNVs that are associated with Salmonella shedding and/or Salmonella colonization. One single nucleotide variant in the C-type lectin MBL1 and one single nucleotide variant in the cytosolic pattern recognition receptor NOD1 was associated with increased risk of on-farm shedding (p = 0.010) and internal colonization tested at slaughter (p = 0.018), respectively. These findings indicate the potential of these variants for genetic selection programs aimed at controlling Salmonella shedding and colonization in pigs.
Margaret H. Ainslie-Garcia; Abdolvahab Farzan; Mohsen Jafarikia; Brandon N. Lillie. Single nucleotide variants in innate immune genes associated with Salmonella shedding and colonization in swine on commercial farms. Veterinary Microbiology 2018, 219, 171 -177.
AMA StyleMargaret H. Ainslie-Garcia, Abdolvahab Farzan, Mohsen Jafarikia, Brandon N. Lillie. Single nucleotide variants in innate immune genes associated with Salmonella shedding and colonization in swine on commercial farms. Veterinary Microbiology. 2018; 219 ():171-177.
Chicago/Turabian StyleMargaret H. Ainslie-Garcia; Abdolvahab Farzan; Mohsen Jafarikia; Brandon N. Lillie. 2018. "Single nucleotide variants in innate immune genes associated with Salmonella shedding and colonization in swine on commercial farms." Veterinary Microbiology 219, no. : 171-177.
Biomarkers are useful tools in research and clinical practice where they are often used to detect and monitor differences in the physiological state of an animal. The proteins IGF-1, IGFBP-3, GHR, CRP, SAA, Hp, IFN-α, IFN-γ, TNF-α, IL-1β, IL-6, IL-10, and IL-18 have been proposed as potential biomarkers for monitoring growth in livestock. The objective of this study was to determine whether hepatic gene expression of these proposed biomarkers is associated with growth performance in nursery pigs. Herd information and growth parameters were collected for 168 piglets from 8 commercial farms in southern Ontario. From these pigs, a subset of liver tissue samples (n = 74) was used for gene expression analysis of the proposed biomarkers. Multivariable linear regression methods were used to determine whether genetic expression of the proposed biomarkers was associated with growth performance in the nursery.
Mackenzie J Slifierz; Robert Friendship; Cornelius Fm De Lange; Marko Rudar; Abdolvahab Farzan. An epidemiological investigation into the association between biomarkers and growth performance in nursery pigs. BMC Veterinary Research 2013, 9, 247 -247.
AMA StyleMackenzie J Slifierz, Robert Friendship, Cornelius Fm De Lange, Marko Rudar, Abdolvahab Farzan. An epidemiological investigation into the association between biomarkers and growth performance in nursery pigs. BMC Veterinary Research. 2013; 9 (1):247-247.
Chicago/Turabian StyleMackenzie J Slifierz; Robert Friendship; Cornelius Fm De Lange; Marko Rudar; Abdolvahab Farzan. 2013. "An epidemiological investigation into the association between biomarkers and growth performance in nursery pigs." BMC Veterinary Research 9, no. 1: 247-247.
There is poor understanding of most aspects of Clostridium perfringens type A as a possible cause of neonatal diarrhea in piglets, and the prevalence and types of C. perfringens present on Ontario swine farms is unknown. To study the prevalence of fecal C. perfringens and selected toxin genes, 48 Ontario swine farms were visited between August 2010 and May 2011, and 354 fecal samples were collected from suckling pigs, lactating sows, weanling pigs, grower-finisher pigs, and gestating sows, as well as from manure pits. The fecal samples were cultured quantitatively, and toxin genes were detected by real-time multiplex polymerase chain reaction (PCR). In mixed multivariable linear analysis, log10C. perfringens in fecal samples from suckling pigs were higher than that of weanling pigs, grower-finisher pigs, and manure pit samples (P <0.05). In mixed multivariable logistic analysis, the C. perfringens isolates recovered from lactating sows (OR = 0.069, P <0.001), gestating sows (OR = 0.020, P <0.001), grower-finishers (OR = 0.017, P <0.001), and manure pits (OR = 0.11, P <0.001) were less likely to be positive for the consensus beta2 toxin gene cpb2 compared to the isolates from suckling pigs. The prevalence of cpb2 in the isolates recovered from weanlings did not differ significantly from suckling pigs. C. perfringens isolates that were positive for cpb2 were more likely to carry the atypical cpb2 gene (atyp-cpb2) (OR = 19, P <0.001) compared to isolates that were negative for cpb2. Multivariable analysis did not identify farm factors affecting the presence of consensus cpb2 and atyp-cpb2 genes. This study provides baseline data on the prevalence of C. perfringens and associated toxin genes in healthy pigs at different stages of production on Ontario swine farms. The study suggests that if C. perfringens type A are involved in neonatal enteritis, there may be strains with specific characteristics that cannot be identified by the existing genotyping system.
Gloria Chan; Abdolvahab Farzan; Glenn Soltes; Vivian M Nicholson; Yanlong Pei; Robert Friendship; John F Prescott. The epidemiology of Clostridium perfringens type A on Ontario swine farms, with special reference to cpb2-positive isolates. BMC Veterinary Research 2012, 8, 156 -156.
AMA StyleGloria Chan, Abdolvahab Farzan, Glenn Soltes, Vivian M Nicholson, Yanlong Pei, Robert Friendship, John F Prescott. The epidemiology of Clostridium perfringens type A on Ontario swine farms, with special reference to cpb2-positive isolates. BMC Veterinary Research. 2012; 8 (1):156-156.
Chicago/Turabian StyleGloria Chan; Abdolvahab Farzan; Glenn Soltes; Vivian M Nicholson; Yanlong Pei; Robert Friendship; John F Prescott. 2012. "The epidemiology of Clostridium perfringens type A on Ontario swine farms, with special reference to cpb2-positive isolates." BMC Veterinary Research 8, no. 1: 156-156.
As part of the C-EnterNet surveillance program of the Public Health Agency of Canada, 122 pooled swine manure samples from 10 farms in Ontario, Canada were collected and tested for Giardia and Cryptosporidium. Giardia duodenalis cysts and Cryptosporidium spp. oocysts were detected using immunofluorescence microscopy. Nested-polymerase chain reaction protocols were performed to amplify the small subunit rRNA gene and the β-giardin gene for G. duodenalis, and the small subunit rRNA gene and the heat shock protein-70 gene for Cryptosporidium spp. The DNA amplicons were sequenced to determine genotypes and species. A mixed multivariable method was used to compare the presence of Giardia and Cryptosporidium in different stages of production. Both Giardia cysts and Cryptosporidium oocysts were present on all tested farms, with 50.8% of the samples positive for G. duodenalis and 44.3% positive for Cryptosporidium spp. by microscopy, and 66.4% and 55.7%, respectively, positive by polymerase chain reaction (PCR). No significant agreement was observed between microscopy and PCR method to detect Giardia and Cryptosporidium (p0.05), however, it was less frequent (odds ratio, OR=0.21 [0.07, 0.63]) among sows. Cryptosporidium was more likely (OR=3.6 [1.3, 9.9]) to be detected in manure pits and weaners (OR=3.3 [1.1, 10.0]) compared to finisher pigs, and it was less frequent (OR=0.06 [0.007, 0.55]) in sows than in finishers (p<0.05). DNA sequencing demonstrated that 92.1% of the Giardia isolates were Assemblage B and 7.9% were Assemblage E. The most prevalent Cryptosporidium were Cryptosporidium parvum (55.4%), and Cryptosporidium sp. pig genotype II (37.5%). These findings indicate that the occurrence of zoonotic isolates of G. duodenalis and Cryptosporidium is very high on swine farms in southern Ontario, and that there is a potential for transmission between swine and humans by means of cyst and oocyst contaminated water or foods.
Abdolvahab Farzan; Lorna Parrington; Tatjana Coklin; Angela Cook; Katarina Pintar; Frank Pollari; Robert Friendship; Jeffrey Farber; Brent Dixon. Detection and Characterization ofGiardia duodenalisandCryptosporidiumspp. on Swine Farms in Ontario, Canada. Foodborne Pathogens and Disease 2011, 8, 1207 -1213.
AMA StyleAbdolvahab Farzan, Lorna Parrington, Tatjana Coklin, Angela Cook, Katarina Pintar, Frank Pollari, Robert Friendship, Jeffrey Farber, Brent Dixon. Detection and Characterization ofGiardia duodenalisandCryptosporidiumspp. on Swine Farms in Ontario, Canada. Foodborne Pathogens and Disease. 2011; 8 (11):1207-1213.
Chicago/Turabian StyleAbdolvahab Farzan; Lorna Parrington; Tatjana Coklin; Angela Cook; Katarina Pintar; Frank Pollari; Robert Friendship; Jeffrey Farber; Brent Dixon. 2011. "Detection and Characterization ofGiardia duodenalisandCryptosporidiumspp. on Swine Farms in Ontario, Canada." Foodborne Pathogens and Disease 8, no. 11: 1207-1213.
A multinomial logistic regression method was used to investigate the risk factors for antimicrobial resistance (AMR) in Salmonella isolated from faecal samples collected on 80 Ontario swine farms in Canada. The samples were classified into three groups including Salmonella-negative samples (S-), Salmonella-positive samples without AMR (S+AMR-) and Salmonella-positive samples with AMR (S+AMR+). The samples collected directly from pigs had a greater chance to be positive for Salmonella with AMR compared to those samples collected from the pen floor. The odds of culturing Salmonella with or without AMR was higher if pelleted feed was used compared with mash or liquid feed (P < 0.001). The faecal samples collected on farrow-to-finish farms had a significant lower chance of testing positive for Salmonella with multidrug resistance than the samples from grow-finisher farms (P = 0.004). The chance of culturing Salmonella without AMR on farms with a continuous system was higher than on farms with an all-in/all-out system (P = 0.009). However, there was no significant association between the flow system and recovery of Salmonella with AMR. The larger farms were more likely to be in S+AMR+ group than in S- group (P < 0.001) whereas herd size did not appear as a risk factor for being in S+AMR- group compared with S- group. These findings indicate that although on-farm antimicrobial use is one component of resistance, there might be other farm management factors that also affect the development of emerging resistant bacterial foodborne pathogens on swine farms. Finding different risk factors for shedding Salmonella with or without antimicrobial resistance would help to take the appropriate approach to each group if a control programme were to be implemented or an intervention applied.
A. Farzan; R. M. Friendship; C. E. Dewey; C. Poppe; J. Funk. Evaluation of the Risk Factors for Shedding Salmonella with or without Antimicrobial Resistance in Swine Using Multinomial Regression Method. Zoonoses and Public Health 2010, 57, 85 -93.
AMA StyleA. Farzan, R. M. Friendship, C. E. Dewey, C. Poppe, J. Funk. Evaluation of the Risk Factors for Shedding Salmonella with or without Antimicrobial Resistance in Swine Using Multinomial Regression Method. Zoonoses and Public Health. 2010; 57 ():85-93.
Chicago/Turabian StyleA. Farzan; R. M. Friendship; C. E. Dewey; C. Poppe; J. Funk. 2010. "Evaluation of the Risk Factors for Shedding Salmonella with or without Antimicrobial Resistance in Swine Using Multinomial Regression Method." Zoonoses and Public Health 57, no. : 85-93.
A clinical field trial was performed to determine the effectiveness of an autogenous Salmonella Typhimurium bacterin compared with a commercial live S. Choleraesuis vaccine in pigs. The association between Salmonella shedding and weight gain was also investigated. Nine cohorts of weaned pigs, (330 to 350 pigs per cohort), were randomly assigned to 1 of 3 treatment groups (injection with S. Typhimurium bacterin, vaccination via water with S. Choleraesuis vaccine, or a control group receiving no vaccine). In each cohort, the average daily gain was calculated for a selected pen throughout the production stage. Pen (pooled) fecal samples were collected bi-weekly and cultured. The odds of Salmonella shedding in both vaccinated groups was higher than in the control group (P < 0.05). The prevalence of Salmonella shedding declined overall as pigs aged (P = 0.04). However, the control pigs showed the smallest decrease in Salmonella shedding over the entire production stage, while prevalence of Salmonella shedding in the vaccinated groups decreased twice as much as the control group over the entire production stage. Salmonella Typhimurium var. Copenhagen DT104, S. Cerro, and S. Agona, which had been isolated on the study farm previously, were recovered from pigs in this study. Shedding of S. Typhimurium var. Copenhagen decreased over time in both vaccine treatment groups. On the other hand, S. Cerro shedding rate was lower in the control pigs compared with vaccinated pigs and S. Agona could be recovered only from the samples collected from S. Choleraesuis vaccinated pigs. The pigs from pens with a higher Salmonella recovery rate experienced slower growth compared with pigs from pens where Salmonella was not isolated. This latter finding indicates that there might be an economic incentive for producers to try to control endemic salmonellosis if effective programs could be developed.
Abdolvahab Farzan; Robert M. Friendship. A clinical field trial to evaluate the efficacy of vaccination in controlling Salmonella infection and the association of Salmonella-shedding and weight gain in pigs. Canadian journal of veterinary research = Revue canadienne de recherche veterinaire 2010, 74, 258 -263.
AMA StyleAbdolvahab Farzan, Robert M. Friendship. A clinical field trial to evaluate the efficacy of vaccination in controlling Salmonella infection and the association of Salmonella-shedding and weight gain in pigs. Canadian journal of veterinary research = Revue canadienne de recherche veterinaire. 2010; 74 (4):258-263.
Chicago/Turabian StyleAbdolvahab Farzan; Robert M. Friendship. 2010. "A clinical field trial to evaluate the efficacy of vaccination in controlling Salmonella infection and the association of Salmonella-shedding and weight gain in pigs." Canadian journal of veterinary research = Revue canadienne de recherche veterinaire 74, no. 4: 258-263.
The objective of this study was to investigate the occurrence of major bacterial foodborne pathogens in swine. In total, 359 samples from manure storage tanks (91) and fresh pooled faeces (268) obtained from finisher (110), sows (78) and weanlings (80) were collected and tested. Campylobacter, Salmonella, Yersinia enterocolitica, Escherichia coli O157 and Listeria monocytogenes were isolated from 36.5%, 31.5%, 5.8%, 3.3% and 3.3% of samples respectively. All E. coli O157 isolates found on 10 farms were tested but none was determined to be E. coli O157:H7. Salmonella and Campylobacter were more likely to be detected from stored manure rather than from fresh faecal samples. Yersinia enterocolitica tended to be detected more commonly from fresh samples than from manure pits. Listeria monocytogenes was not recovered from manure pits or from sow faecal samples and only infrequently found in the faeces of weanling pigs and finisher pigs. The proportion of positive samples showed a seasonal change. Salmonella was twice as likely not be recovered in winter, whereas the chance of culturing Campylobacter was higher in winter. The 113 Salmonella isolates recovered on 24 farms and the four most common serovars were Salmonella Typhimurium var. Copenhagen (31.0%), Salmonella Derby (12.4%), S. Typhimurium (10.6%) and Salmonella Agona (10.6%). Of 131 Campylobacter isolates recovered on 21 farms, 118 isolates were Campylobacter coli and 13 isolates could not be speciated. Fifteen of 21 Y. enterocolitica isolates found on 15 farms were detected in finisher pigs. The sero/biogroups of Y. enterocolitica were O3/biotype 4 (16 isolates), O6,30/biotype 1A (three isolates), O5/biotype 1A (one isolate) and O8/biotype 1B (one isolate). These findings provide baseline information on the distribution of important zoonotic pathogens in swine and indicate that pigs should be considered as a possible source of foodborne diseases in humans.
A. Farzan; R. M. Friendship; A. Cook; F. Pollari. Occurrence of Salmonella, Campylobacter, Yersinia enterocolitica, Escherichia coli O157 and Listeria monocytogenes in Swine. Zoonoses and Public Health 2010, 57, 388 -396.
AMA StyleA. Farzan, R. M. Friendship, A. Cook, F. Pollari. Occurrence of Salmonella, Campylobacter, Yersinia enterocolitica, Escherichia coli O157 and Listeria monocytogenes in Swine. Zoonoses and Public Health. 2010; 57 (6):388-396.
Chicago/Turabian StyleA. Farzan; R. M. Friendship; A. Cook; F. Pollari. 2010. "Occurrence of Salmonella, Campylobacter, Yersinia enterocolitica, Escherichia coli O157 and Listeria monocytogenes in Swine." Zoonoses and Public Health 57, no. 6: 388-396.
In order to describe the farm-level Salmonella status, 113 Ontario swine farms were tested for Salmonella one to five times within the time period 2001–2006. During 422 visits, 6844 fecal samples were collected and cultured for Salmonella. Salmonella was recovered from 437 (6.38%) of the fecal samples, and 69 (61%) of the farms had at least one positive sample over the entire period of the study. Salmonella was not recovered on 11 farms of the 54 farms visited five times, nor from 7 of the 17 farms visited four times. On seven farms Salmonella was not recovered over the first four visits but were cultured on the fifth visit. The isolates belonged to 30 different serovars, and serogroup B and C1 were the most common serogroups. Salmonella Typhimurium (including var. Copenhagen) was the most common serovar recovered from 35.5% of the farms with DT104 as the most frequent phage type. Only 24% of the total random variance in prevalence of Salmonella was due to repeated measurement, while the variation in prevalence of Salmonella Typhimurium (including var. Copenhagen) and DT104 due to repeated measurement was 37% and 52% of total random variance, respectively. Although the observed trends may be partly attributed to the different culturing methods, different types of samples, and sampling strategies used in each year, it may also denote the dynamics of Salmonella as a bacterial population on swine farms. These findings indicate that monitoring over time may be useful to detect changes in Salmonella on swine farms.
Abdolvahab Farzan; Robert M. Friendship; Catherine E. Dewey; Cornelis Poppe; Julie Funk; Catherine A. Muckle. A Longitudinal Study of the Salmonella Status on Ontario Swine Farms Within the Time Period 2001–2006. Foodborne Pathogens and Disease 2008, 5, 579 -588.
AMA StyleAbdolvahab Farzan, Robert M. Friendship, Catherine E. Dewey, Cornelis Poppe, Julie Funk, Catherine A. Muckle. A Longitudinal Study of the Salmonella Status on Ontario Swine Farms Within the Time Period 2001–2006. Foodborne Pathogens and Disease. 2008; 5 (5):579-588.
Chicago/Turabian StyleAbdolvahab Farzan; Robert M. Friendship; Catherine E. Dewey; Cornelis Poppe; Julie Funk; Catherine A. Muckle. 2008. "A Longitudinal Study of the Salmonella Status on Ontario Swine Farms Within the Time Period 2001–2006." Foodborne Pathogens and Disease 5, no. 5: 579-588.
The purpose of this study was to evaluate Salmonella ELISA tests and a culture technique to determine Salmonella status using samples collected from commercial herds. Faecal samples from 15 finisher pigs on each of 40 swine farms were cultured for Salmonella. Sera from the same 600 pigs were analysed for the presence of antibodies to Salmonella by means of two different ELISA kits Salmotype (Salmotype® Labordiagnostik, Leipzig, Germany) and IDEXX (Herdchek* Salmonella; IDEXX Laboratories, Schiphol-Rijk, Noord-Holland, The Netherlands). The Salmotype ELISA test demonstrated a moderate ability to differentiate culture-positive pigs from culture-negative pigs while IDEXX was relatively poor in classifying those pigs correctly (The area under the curves were 0·79 and 0·65 for Salmotype and IDEXX respectively). The maximum value of sensitivity plus specificity was gained at the cut-off optical density (OD) [ges ]25% for Salmotype (sensitivity 0·65, specificity 0·84) and at the OD [ges ]9% for IDEXX (sensitivity 0·59, specificity 0·69). The maximum herd sensitivity and herd specificity was 0·64 (95% CI 0·49–0·79) and 0·72 (95% CI 0·59–0·86) for the Salmotype test and 0·73 (95% CI 0·59–0·87) and 0·62 (95% CI 0·47–0·77) for the IDEXX. Culture and the ELISA tests showed fair agreement at the herd level (κ=0·3, PPSalmonella isolated in our study and need to be revised based upon the Salmonella serovar distribution in Ontario.
A. Farzan; R. M. Friendship; C. E. Dewey. Evaluation of enzyme-linked immunosorbent assay (ELISA) tests and culture for determining Salmonella status of a pig herd. Epidemiology and Infection 2006, 135, 238 -244.
AMA StyleA. Farzan, R. M. Friendship, C. E. Dewey. Evaluation of enzyme-linked immunosorbent assay (ELISA) tests and culture for determining Salmonella status of a pig herd. Epidemiology and Infection. 2006; 135 (2):238-244.
Chicago/Turabian StyleA. Farzan; R. M. Friendship; C. E. Dewey. 2006. "Evaluation of enzyme-linked immunosorbent assay (ELISA) tests and culture for determining Salmonella status of a pig herd." Epidemiology and Infection 135, no. 2: 238-244.
The objective of this study was to determine whether the shedding and antibody titre to Salmonella was lower for pig herds provided liquid-feed compared to those on traditional dry rations. Twenty liquid-feeding farms and 61 dry-feeding farms were selected. The amount of antibodies to Salmonella in sera from 15 finisher pigs on each of 80 Ontario swine farms was analyzed by means of enzyme-linked immunosorbent assay (ELISA). In addition, the presence of Salmonella on the 20 liquid-feeding farms and 21 of the dry-feeding farms was assessed by culture of 15 fecal samples taken directly from finisher pigs and five pooled pen-fecal samples at each farm. A cut-off of OD% 10 was used. The Salmonella sero-prevalence differed between the two groups of farms. At least one pig tested sero-positive on 98% of the dry-feeding farms and 84% of the liquid-feeding farms (P<0.05). A multi-variable mixed linear regression model with the farm as a random variable and farm factors as the fixed effects was fitted. Crude optical density (OD) of the individual pig was considered as the continuous dependent variable. Dry-feeding and antimicrobial daily usage was associated with crude OD (P<0.05). In addition, crude OD increased with increasing herd size (P<0.05). Salmonella was isolated from 25 out of 420 fecal samples (6%) from dry-feeding farms compared to three out of 400 samples (0.8%) from liquid-feeding farms. Eight of the dry-feeding farms (38%) tested positive compared to only three of the liquid-feeding farms (15%). Salmonella was also recovered from the pen environment on five dry-feeding farms but were not isolated from the facilities using liquid-feeding. Salmonella Typhimurium was isolated from four farms in the dry-feed group and on one farm with liquid-feeding. The one S. Typhimurium isolate from the liquid-feeding farm exhibited no antimicrobial resistance, but those from dry-feeding farms were resistant to four or more antimicrobial agents. The results of the logistic regression, with farm as a random effect showed that dry-feeding [OR=2.7 (1.1-15.1)] and continuous flow system [OR=2.3 (1.2-12.7)] increased risk of finding Salmonella in the individual pig. These findings indicate that liquid-feeding and all-in all-out management of the grower-finisher barns can reduce the Salmonella prevalence.
Abdolvahab Farzan; Robert M. Friendship; Catherine E. Dewey; Keith Warriner; Cornelius Poppe; Kim Klotins. Prevalence of Salmonella spp. on Canadian pig farms using liquid or dry-feeding. Preventive Veterinary Medicine 2006, 73, 241 -254.
AMA StyleAbdolvahab Farzan, Robert M. Friendship, Catherine E. Dewey, Keith Warriner, Cornelius Poppe, Kim Klotins. Prevalence of Salmonella spp. on Canadian pig farms using liquid or dry-feeding. Preventive Veterinary Medicine. 2006; 73 (4):241-254.
Chicago/Turabian StyleAbdolvahab Farzan; Robert M. Friendship; Catherine E. Dewey; Keith Warriner; Cornelius Poppe; Kim Klotins. 2006. "Prevalence of Salmonella spp. on Canadian pig farms using liquid or dry-feeding." Preventive Veterinary Medicine 73, no. 4: 241-254.