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This study was conducted to determine the frequency of isolation of salmonella and their microbial resistance profiles across different commercial poultry feeds sold in Imo State, Nigeria. Thirtysix bulk feed samples were colleted from 154 bag across different feed types and brands which included Guinea (GF), Top (TF), Vital (VF), Extra (EF), Animal care (AF) and livestock (LF) feeds. Introduction Factors such as quality feed, sound health management and rearing environment are indispensable complements to genetic techniques for livestock improvement in the tropics.(1) This is because farm animals are vulnerable to numerous diseases of economic and public health importance. Prominent among these are salmonella infections of poultry, which have been shown to be of critical importance especially in Nigeria (2-4). Several studies have shown that sources of salmonella infection in poultry include contaminated products, feeds and feed ingredients, human wastes, mouse and rat droppings among others.(5-8) Hygienic production of poultry feeds is therefore important and involves the processing of feeds under health hazard free conditions. This usually starts from the harvesting of the feed ingredients, to the storage, processing, packaging transporting and eventual marketing of the bagged feeds at the various sales outlets from where the farmers collect to feed their animals.(9) In developed countries, measures such as Hazard Analysis and Critical Control Point (HACCP) program are been adopted to control salmonella and other pathogenic micro-organism to near zero tolerance in poultry feeds. In developing countries such as Nigeria however, such programs are not in place and there are no reliable data on the prevalence and anti-microbial susceptibility of salmonella isolates from poultry feed.(10) Overall, the challenge for animal nutritionist and commercial feed producers anywhere is to consistently monitor all segment of feed production, and measure those variables that are good indicators of quality control against pathogenic organisms such as salmonella. This is imperative since commercial feeds and feed ingredients are major potential routes of disease dissemination outside the control of the farmer.(11, 12) Furthermore, since commercial feeds are usually sourced from wide geographical areas, they remain potentially, major vehicles for the introduction of bacteria harboring novel resistance factors to a local farm environment.(13) Antibiotic resistance among bacteria genera is a worldwide problem.(14) 2 OJHAS Vol 5 Issue 2, 2017-2-3 Frequency Of Isolation Of Salmonella From Commercial Poultry Feeds And Their Anti-Microbial Resistance Profiles, Imo State, Nigeria The rate at which resistance arise among bacterial populations has been ed to be contingent on the extent of use of a particular antibiotics in a particular environment.(15) The salmonella organism contributed by the different raw materials used in compounding a commercial feed may harbor resistance factors reflecting antibiotic use in their area of origin. Discussion Monitoring of microbial contamination of animal production environment is an important first step in determining how such contaminants especially salmonella pass through the food chain.(22) This is because, in general the transmission of salmonella spp through the environment has been shown to cyclic, and poultry feeds have historically been viewed as important links for contamination in poultry.(23,24) Although little is known about the relative significance of different sources of contamination of poultry feeds, it may depend partially upon the contamination levels of individual feed ingredients used in mixing the feed.(25) The obvious disparity in bacterial load of the feeds analyzed in this study may be reflecting this since animal protein sources have been shown to harbor heavier bacterial growth than other feed raw materials, especially locally processed fish wastes.(25) It is probable that high incidence of bacterial overgrowth recorded in the layer mashes is due to the use of such fish wastes in commercial feed mixing. It would seem from the present results that guinea and vital feeds are particularly prone to this practice. Chemical amendment, heat treatment, irradiation and careful sourcing of materials are proven methods of reducing bacterial loads in feed ingredient.(24) The present results of anti-microbial resistance of salmonella isolates from poultry feeds highlight again the severally ed multi-drugs resistance of bacterial of the Enterbacteriaceae family in Imo State.(13,14,28-30) The present data is however, of particular public health interest since some of the isolated organisms could be zoonotic. While these organisms were not identified to genera level, unpublished field data by Anyanwu (31) and Okoli (32) suggest that S. enteritidis, S. typhimurium and S montevideo are involved in poultry contamination in this study area. The 37.5% resistance recorded for oxfloxacin is again of interest since fluoroquinolones are currently the drug of choice in the treatment of both human and animal salmonellosis in the study area. The low to zero resistance of other quinolones and aminoglycosides (gentamycin and streptomycin) are in agreement with earlier results on E. coli resistance in the study area.(13,14,29,30) These earlier works also highlighted similar high resistances against the cheap, readily available first line antibiotics such as ampicillin, tetracycline, nitrofurantoin, and cotrimoxazole among others recorded in the present study. Conclusion The relatively high prevalence of salmonella in commercial feeds recorded in this study highlights the need for institution of salmonella monitoring measures and regulation in the feed industry in Nigeria.()，英语论文，英语论文 |
