Browsing by Author "Rajashekara, G."
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Item Antimicrobial resistance and genotypic diversity of Campylobacter isolated from pigs, dairy, and beef cattle in Tanzania(Frontiers in Microbiology, 2015-11-12) Kashoma, I. P.; Kassem, I. I.; Kumar, A.; Kessy, B. M.; Gebreyes, W.; Kazwala, R. R.; Rajashekara, G.Foodborne Campylobacter infections pose a serious threat to public health worldwide. However, the occurrence and characteristics of Campylobacter in food animals and products remain largely unknown in Tanzania. The objective of this study was to determine the revalence, antibiotic resistance, and genetic profiles (sequence types, STs) of Campylobacter isolated from feces of pigs and dairy and beef cattle in Tanzania. Overall, 259 (∼30%) of 864 samples were positive for Campylobacter spp, which were detected in 32.5, 35.4, and 19.6% of the pig, dairy, and beef cattle samples, respectively. Multiplex PCR analysis identified 4.5 and 29.3% of the Campylobacter isolates as C. coli and C. jejuni, respectively. The majority (91.9%) of the isolates from pig samples were identified as C. coli, while C. jejuni accounted for 65.5% of the isolates from cattle. Antimicrobial susceptibility testing using the disk diffusion assay and the broth microdilution method revealed resistance to: ampicillin (Amp) (70.3% and 75.7%, respectively), gentamicin (Gen) (1.8% and 12.6%), streptomycin (Str) (65.8 and 74.8%), erythromycin (Ery) (41.4 and 48.7%), tetracycline (Tet) (18.9 and 23.4%), and ciprofloxacin (Cip) (14.4 and 7.2%). Resistance to nalidixic acid (Nal) (39.6%), azithromycin (Azm) (13.5%), and chloramphenicol (Chl) (4.5%) was determined using the disk diffusion assay only, while resistance to tylosin (Tyl) (38.7%) was quantified using the broth microdilution method. Multilocus sequence typing of 111 Campylobacter isolates resulted in the identification of 48 STs (26 C. jejuni and 22 C. coli) of which seven were novel (six C. jejuni and one C. coli). Taken together, this study revealed the high prevalence, genetic diversity and antimicrobial resistance of Campylobacter in important food animals in Tanzania, which highlights the urgent need for the surveillance and control of Campylobacter in this country.Item Campylobacter species isolated from Pigs in grenada exhibited novel clones: genotypes and antimicrobial resistance profiles of sequence types(FOODBORNE PATHOGENS AND DISEASE, 2017-07-01) Amadi, V.; Mattew-Belmar, V.; Subbarao, C.; Kashoma, I.; Rajashekara, G.; Sharma, R.; Hariharan, H.; Stone, D.Infections caused by Campylobacter species pose a severe threat to public health worldwide. However, in Grenada, the occurrence and characteristics of Campylobacter in food animals, including pigs, remain mostly unknown. In this study, we identified the sequence types (STs) of Campylobacter from young healthy pigs in Grenada and compared the results with previous studies in Grenada and other countries. Antimicrobial resistance patterns and diversity of the Campylobacter clones were evaluated. Ninety-nine Campylobacter isolates (97 Campylobacter coli and 2 Campylobacter jejuni) were analyzed by multilocus sequence typing. Eighteen previously reported STs and 13 novel STs were identified. Of the 18 previously reported STs, eight STs (ST- 854, -887, -1068, -1096, -1445, -1446, 1556, and -1579) have been associated with human gastroenteritis in different geographical regions. Among these 18 previously reported STs, ST-1428, -1096, -1450, and -1058 predominated and accounted for 18.2%, 14.1%, 11.1%, and 8.1% of all isolates, respectively. Of the 13 novel STs, ST-7675 predominated and accounted for 20% (4 of 20 isolates), followed by ST-7678, -7682, and -7691, each accounting for 10% (2 of 20 isolates). Antimicrobial resistance testing using Epsilometer test revealed a low resistance rate (1–3%) of all C. coli/jejuni STs to all antimicrobials except for tetracycline (1–10.1%). Some of the C. coli STs (13 STs, 24/99 isolates, 24.2%) were resistant to multiple antimicrobials. This is the first report on antimicrobial resistance and multidrug resistance patterns associated with Campylobacter STs recovered from swine in Grenada. This study showed that pigs in Grenada are not major reservoirs for STs of C. coli and C. jejuni that are associated with human gastroenteritis worldwide.Item The emergence of antibiotic resistance in poultry farms(Burleigh Dodds Science Publishing Limited, 2016-12-29) Kassem, I. I.; Helmy, Y. A.; Kashoma, I. P.; Rajashekara, G.The use of antibiotics in poultry farming has enhanced production via effectively controlling infectious diseases and promoting growth of birds, allowing the industry to cope with the increasing consumer demands and provide safe and affordable products. However, the use of antibiotics results in the selection of antibiotic-resistant bacteria, including established animal and human pathogens. The emergence and proliferation of resistant pathogens and the cognate decrease in the efficacy of antibiotic therapy pose a concrete risk to public health and sustainable farming. Consequently, the need to tightly regulate the use of antibiotics in poultry farming has been highlighted as a pre-emptory necessity.Item The emergence of antibiotic resistance in poultry farms(Burleigh Dodds Science Publishing Limited, 2016-12-29) Kassem, I. K.; Helmy, Y. A.; Kashoma, I. P.; Rajashekara, G.The increasing human population and cognate demands on wholesome and nutritious foods have exerted an indelible impact on modern agricultural practices. In addition, producer and consumer awareness has shaped a modern agricultural stewardship that accounts for affordability without jeopardizing public health, resource conservation, animal health and humane farming ethos. Therefore, now more than ever, there is a need to optimize agricultural production to achieve sustainability and food security and safety. Indeed, this also applies to poultry production, which is continuously evolving in breadth and practice. For example, broiler farming has witnessed a continuous improvement, which is evidenced by producing heavier birds in shorter growth cycles. Specifically, a 1.13 kg chicken was produced in 112 days in 1925 in comparison to 70 days in 1950. As of 2010, production of a 2.27 kg chicken is possible in less than 50 days (Krishnasamy et al., 2015). The expansion in the poultry industry and consumer demand for animal proteins were also evident in a recent Census of Agriculture report that showed that there were 233 770 poultry farms in the United States in 2012. Furthermore, approximately 96.4 billion eggs, 8.69 billion broilers and 233 million turkeys were produced in 2015, and the combined value of production was estimated at $48 billion (United States Department of Agriculture, USDA, 2015).Item Insights into potential pathogenesis mechanisms associated with Campylobacter jejuni-induced abortion in ewes(BMC Veterinary Research, 2014-11-25) Sanad, Y. M.; Jung, K.; Kashoma, I.; Zhang, X.; Kassem, I. I.; Saif, Y. M.; Rajashekara, G.Background: Campylobacter jejuni is commonly found in the gastrointestinal tract of many food-animals including sheep without causing visible clinical symptoms of disease. However, C. jejuni has been implicated in ovine abortion cases worldwide. Specifically, in the USA, the C. jejuni sheep abortion (SA) clone has been increasingly associated with sheep abortion. In vivo studies in sheep (the natural host) are needed to better characterize the virulence potential and pathogenesis of this clone. Results: Pregnant ewes intravenously (IV) or orally inoculated with ovine or bovine abortion-associated C. jejuni SA clones exhibited partial or complete uterine prolapse with retained placenta, and abortion or stillbirth, whereas delivery of healthy lambs occurred in pregnant ewes inoculated with C. jejuni 81–176 or in the uninfected group. In sheep inoculated with the SA clone, histopathological lesions including suppurative necrotizing placentitis and/or endometritis coincided with: 1) increased apoptotic death of trophoblasts, 2) increased expression of the host genes (e.g. genes encoding interleukin IL-6 and IL-15) related to cellular necrosis and pro-inflammatory responses in uterus, and 3) decreased expression of the genes encoding GATA binding protein 6, chordin, and insulin-like 3 (INSL3) that account for embryonic development in uterus. Immunohistochemistry revealed localization of bacterial antigens in trophoblasts lining the chorioallantoic membrane of ewes inoculated with the C. jejuni SA clone. Conclusions: The results showed that C. jejuni SA clones are capable of causing abortion or stillbirth in experimentally infected sheep. Furthermore, down- or up-regulation of specific genes in the uterus of infected pregnant ewes might implicate host genes in facilitating the disease progression. Since the C. jejuni SA strains share genotypic similarities with clones that have been isolated from human clinical cases of gastroenteritis, these strains might represent a potential public health risk.Item Organic or antibiotic-free labeling does not impact the recovery of enteric pathogens and antimicrobial- resistant Escherichia coli from fresh retail chicken(FOODBORNE PATHOGENS AND DISEASE, 2014-12-12) Mollenkopf, D. F.; Cenera, J. K.; Bryant, E. M.; King, C. A.; Kashoma, I.; Kumar, A.; Funk, J. A.; Rajashekara, G.; Wittum, T. E.We investigated the implied health benefits of retail chicken breast labeled as ‘‘organic’’ or ‘‘antibiotic-free’’ when compared to conventional products based on frequency of contamination by Salmonella spp., Campylobacter spp., and coliform bacteria resistant to fluoroquinolones, extended-spectrum cephalosporins, or carbapenems. We purchased 231 prepackaged chicken breasts from 99 grocery stores representing 17 retail chains in Ohio, Michigan, and Pennsylvania from June to September 2012. Ninety-six (41.5%) packages were labeled ‘‘antibiotic free’’ and 40 (17.3%) were labeled ‘‘organic,’’ with the remaining 95 (41.1%) making neither label claim. Salmonella were recovered from 56 (24.2%) packages, and the recovery rate was not different between product types. Five percent of packages contained Salmonella carrying the extended-spectrum cephalosporin resistance gene blaCMY-2, representing 21.4% of Salmonella isolates. Campylobacter spp. were recovered from 10.8% of packages, with observed recovery rates similar for the three product types. Using selective media, we recovered Escherichia coli harboring blaCMY-2 from over half (53.7%) of packages, with similar recovery rates for all product types. In addition, we recovered E. coli carrying blaCTX-M from 6.9% of packages, and E. coli with QRDR mutations from 8.2% of packages. Fluoroquinolone-resistant E. coli recovered using selective media were more common ( p < 0.05) in conventional (18.9%) compared to organic (0) and antibiotic-free (2.1%) packages. Our results indicate that, regardless of product type, fresh retail chicken breast is commonly contaminated with enteric pathogens associated with foodborne illness and commensal bacteria harboring genes conferring resistance to critically important antimicrobial drugs.Item Phenotypic and genotypic diversity of thermophilic Campylobacter spp. in commercial Turkey Flocks: A longitudinal study(FOODBORNE PATHOGENS AND DISEASE, 2014-11-11) Kashoma, I. P.; Kumar, A.; Sanad, Y. M.; Gebreyes, W.; Kazwala, R. R.; Garabed, R.; Rajashekara, G.Poultry are recognized as a main reservoir of Campylobacter spp. However, longitudinal studies investigating the persistence of Campylobacter on commercial meat turkeys are rare. The objectives of this study were to determine the prevalence, antimicrobial susceptibility, and persistence of genotypically related strains of Campylobacter spp. recovered from three commercial turkey farms in Ohio belonging to a single producer. Eight hundred ten samples were collected from birds aged 1 week to slaughter, consisting of 750 fecal droppings and 60 ceca at slaughter. Overall Campylobacter prevalence was 55.9%. Multiplex polymerase chain reaction (PCR) confirmed 72.3% of all isolates as C. coli, 5.3% as C. jejuni, 10.6% as both, and 11.9% as other Campylobacter spp. PCR restriction fragment length polymorphism of the flaA gene subtyping detected 70 types—62 for C. coli and 8 for C. jejuni isolates—with most (80%) of flaA-types constituting farm homogeneous groups. Multilocus sequence typing of 99 selected Campylobacter isolates resulted in 23 sequence types (STs), consisting of 8 STs for C. jejuni and 15 STs for C. coli isolates. Six novel STs—four for C. jejuni and two—for C. coli, were detected. In a subset of isolates (n = 98) tested for antimicrobial resistance, the most common resistance was to tetracycline (95%), followed by azithromycin (43%), while 42% and 18% of the isolates were resistant to ciprofloxacin and erythromycin, respectively. All isolates were susceptible to florfenicol. C. coli isolates displayed a higher proportion of resistance than C. jejuni to most antimicrobials. This study highlights the high prevalence, genotypic diversity, and antimicrobial resistance of Campylobacter spp. in commercial turkey from farm to slaughter.