Incidence of foodborne pathogens on retail broilers

The Current Status of the Alternative Use to Antibiotics in Poultry Production: An African Perspective

Over the years the growth and health of food-producing animals have been enhanced by the use of antibiotics. These have helped reduce on-farm mortalities, lower incidences of diseases and more importantly improve productivity. Generally, the utilization of antibiotics in feed has been reevaluated since bacterial pathogens have established and shared a variety of antibiotic resistance mechanisms that can easily be spread within microbial communities. Multiple countries have introduced bans or severe restrictions on the non-therapeutic use of antibiotics. This has therefore warranted the urgent need for alternatives. Africa is facing its own challenges as it has been reported to be one of the continents with the highest number of foodborne diseases with approximately 91 million related diseases and 137,000 death per annum. Stakeholder and policy direction has been put in place to curb this escalation; however, the problem persists. The use of alternatives has been recommended and some successfully used in other countries as well as Africa, including pro- and prebiotics and phytochemicals. This then leads to the core aim of this review which is to (1) determine the extent to which antimicrobial-resistant pathogens have affected Africa, (2) assess the current measures put in place by Africa to reduces antimicrobial resistance and finally (3) explore the alternative use of antibiotics in poultry production. Improved sanitary conditions and farm biosecurity are important alternatives that could be adopted by farmers instead of depending on antibiotic drugs for disease control and prevention.

Molecular detection of the Aeromonas virulence aerolysin gene in retail meats from different animal sources in Egypt

Meat commonly contain the same Aeromonas spp. which occur in human diarrhoeal and non-diarrhoeal faecal samples. Motile Aeromonas were isolated from 5.6% of total 302 samples. The distribution of the isolates were 5.9 and 5.2% in fresh and frozen samples, respectively. Of the 302 samples taken of the four animal meat species investigated, the genus Aeromonas were isolated in 12.3% of the fresh samples collected from buffalo meat, in 6.5% of the samples collected from sheep meat and 14.0% from the samples collected from the cattle frozen meat samples. The camel meat did not reveal any Aeromonas isolates. Aeromonas hydrophila was isolated as the most prevalent species with 6.8%, followed by Aeromonas caviae with 2.7% and Aeromonas sobria with 2.1% from the total meat samples. Aerolysin toxin gene (aerA) was detected in 3/17 isolates of A. hydrophila isolated from contaminated meat. Infection due to bacterial pathogen with such virulent factor through contact with contaminated meat while handling them, poses health hazards to humans.

Occurrence of selected foodborne pathogens on poultry and poultry giblets from small retail processing operations in Trinidad

We conducted a study to determine quantitatively and qualitatively the presence of Campylobacter spp., Escherichia coli, staphylococci, total coliforms, total aerobic bacteria, and Salmonella on broiler carcasses from selected small retail processors in Trinidad. We used standard media and procedures for detection and quantification. All carcass and weep samples were positive for aerobic bacteria, E. coli, total coliforms, and staphylococci. Significant differences in the mean counts of aerobic bacteria were observed for samples of carcass (P = 0.001), weep (P = 0.038), and liver and heart (P = 0.017). There was a significant difference (P < 0.05) in the prevalence of E. coli and Campylobacter for liver and heart samples and gizzard samples across various areas (health divisions) in Trinidad and for Campylobacter jejuni and Campylobacter coli for offal samples. The prevalence of Salmonella in carcass, drip, gizzard, and liver and heart samples was 7.3, 3.1, 2.1, and 1.0%, respectively, and three serotypes, Salmonella Kiambu (53.8%), Salmonella Kentucky (38.5%), and Salmonella Mbandaka (7.7%) were isolated. Of the six groups of microbes considered with respect to sale activity, the differences in the prevalence of Campylobacter in medium-activity sale shops (95.8%) and low-activity sale shops (83.3%) and the mean counts of staphylococci for medium-activity sale shops (5.5 +/- 0.9) and low-activity sale shops (5.1 +/- 0.8) were statistically significant (P < 0.05). Carcasses rinsed in a stagnant system had a significantly higher (P < 0.05) prevalence (92.3%) and mean count per milliliter (3.1 +/- 0.7) for Campylobacter compared with 77.8% and 2.7 +/- 0.7 for shops that rinsed with constantly running water. The frequency of rinse water change significantly (P = 0.04) affected the prevalence of Salmonella on carcasses. It is recommended that a quality control system be introduced for these shops, particularly with respect to evisceration and rinsing practices.

Comparison of ELISA and PCR vis-à-vis cultural methods for detecting Aeromonas spp. in foods of animal origin

The present study was conducted to assess the best method of the most commonly used methods for detection of aeromonads in foods of animal origin. With this objective an OMP based indirect plate ELISA and a duplex-PCR using primers targeting aerolysin gene and 16S rRNA gene and yielding amplicons of 252 bp and 599 bp, respectively, were standardized. The standardized protocols and the conventional cultural method were then compared for their respective sensitivities and specificities for detecting aeromonads from chicken and milk samples. Both the standardized assays were found to be highly specific for Aeromonas. The efficiency of the standardized indirect-ELISA and duplex-PCR protocols was assessed by artificial inoculation studies with varying concentrations of Aeromonas cells inoculated in chicken and milk samples followed by enrichment in Alkaline Peptone Water supplemented with 10 mg/ml cephalothin (APW-C) for 12 h. The results revealed that indirect-ELISA was able to detect a minimum of 10(3) cells/ml or g of Aeromonas cells in spiked milk and chicken samples, respectively. Whereas, duplex-PCR and cultural method were able to detect as low as 1 cell/ml or g of Aeromonas cells in spiked milk and chicken samples. The developed assays were also tested for their efficiency to detect Aeromonas spp. in naturally contaminated milk and chicken samples. Out of a total 50 milk samples screened for presence of Aeromonas by the three methods viz., indirect-ELISA, duplex-PCR and cultural method only 1 (2%) turned out to be positive showing positive results by all three methods. Similarly, 50 samples of chicken were tested by all three methods. Three samples (6%) turned out to be positive and here again by all the three methods.

Recovery of Salmonella from retail broilers by a whole-carcass enrichment procedure

Fresh whole broiler carcasses were purchased from grocery stores over a 20-week period. Carcasses were selected on the basis of their having intact packages and unique U.S. Department of Agriculture (USDA) plant numbers and sell-by dates, such that each bird represented a single processing plant-processing day combination. Carcasses were tested for Salmonella with a rinse aliquot obtained after whole-bird incubation in the rinse media for 24 h. On the basis of the number of unique processing plants (USDA plant numbers) and expiration dates involved, the number of birds available each week ranged from 6 to 17. Over the 20-week period, 251 independent carcasses from 14 processing plants were tested. The percentages of carcasses testing positive for Salmonella ranged from 0 (for 1 week) to >60% (for 3 weeks). For only 4 of the 20 weeks was an incidence of Salmonella-positive carcasses of <20% found. For the entire 20-week study, 85 (33.9%) of the 251 carcasses tested were found to be Salmonella positive. For those processing plants from which >10 carcasses were obtained, the percentages of carcasses testing positive for Salmonella ranged from <20 (two plants) to >40% (four plants). These results indicate that a whole-carcass enrichment may be more sensitive for the detection of Salmonella-positive carcasses than the traditional whole-carcass rinse followed by immediate testing of a subsample aliquot when small numbers of Salmonella are expected.