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    Productive and reproductive performance of Friesian cows at Kitulo livestock multiplication unit, Tanzania
    (Tanzania Veterinary Journal, 2015-02-12) Kashoma, I, P.; Mwingira, S, M.; Werema, C, W.; Kessy, B, M.
    Retrospective data were collected to assess reproductive and productive performance of Friesian dairy cows reared at Kitulo Livestock Multiplication Unit, Tanzania. Records of 314 cows within consecutive five productive periods; 2009 - 2014 were analyzed using Statistical Package for SocialScience (SPSS). The overall mean age at first calving (AFC), calving interval (CI), days open (DO), number of services per conception (NSPC), lactation length (LL) and total lactation milk yield (TLMY) were 1151.72±9.63 days, 404.57±1.54 days, 121.82±1.24 days,1.83±0.24, 306.54±5.53 days and 5,042.12±23.73 kg, respectively. CI differed significantly (P < 0.05) as it decreased with increasing parity but did not affect the TLMY. Number of services per conception positively correlated with DO and CI but negatively correlated with parity. Total lactation milk yield was significantly (P < 0.05) influenced by parity and lactation length, but TLMY had no significant (P > 0.05) effect on the average number of services per conception. It is concluded that reproductive and productive performance of Friesian dairy cows in the present study were low to moderate so it is required to improve management practices at the farm for better reproductive and productive performance.
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    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.
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    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.
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    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.
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    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.