Effect of temperature (cooking and freezing) on the concentration of oxytetracycline residue in experimentally induced birds

Aim: The objective of this study was to determine the effect of varying temperatures (different cooking methods and freezing) on the concentration of oxytetracycline (OTC) residues in tissues of broiler birds. Materials and Methods: Fifty, 5-week-old birds were purchased and acclimatized for 3 weeks while being fed antibiotic-free feed and water. Four birds were then tested for residue and in the absence; the remaining birds were injected intramuscularly with oxytetracycline at its therapeutic dose. Muscle and liver samples of the treated birds were harvested and checked for OTC residues before subjecting them to boiling, microwaving, and roasting. The three plate test was used for the residue detection. Results: OTC was detected at both pH 6.0 and pH 7.2 but not detected at pH 8.0. Roasting and boiling significantly reduced the concentration of oxytetracycline in muscle by 53.6% and 69.6%, respectively, at pH 6.0, microwaving reduced the concentration by 49.1% but was not statistically significant. The same pattern was followed at pH 7.2 with reduction of 34.3%, 53.2%, and 67.7% for microwaved, roasted, and boiled. For the liver tissues, there was a significant reduction in the concentration for both pH: 6.0 (57.75%, 79.75%, and 89%; pH 7.2 (48.06%, 79.6%, and 88.79%) for boiled, microwaved, and roasted samples. Boiling had a greater reduction effect for muscle samples while roasting had a greater reduction in liver samples at both pHs. Freezing at -10°C had no effect on the concentration of OTC even after 9 days. Conclusion: The significant reduction of OTC concentration by cooking indicates that consumers may not be at risk of the effects of OTC residues in meat, but microwaving meat may not reduce the concentration below the maximum residue limit if the initial concentration is very high. Therefore, routine monitoring of drug residues in farms and abattoirs is still advocated

Screening for tylosin and other antimicrobial residues in fresh and fermented (nono) cow milk in Delta state, South-South, Nigeria

Background and Aim: Milk is a food that contains almost all the essential nutrients needed for growth and maintenance for both young and old animals and man. Since quite nutritious and in high demand, dairy products should be free of both chemical and biological contaminants. Unfortunately, antibiotics used in the treatment of infectious diseases in dairy cattle are often seen in their products if withdrawal periods of those drugs are not observed before milking. This study aimed to detect the presence of antibiotics and the level of tylosin in fresh and fermented (nono) milk from cows in Delta state, Nigeria. Materials and Methods: Two hundred and five samples comprising 126 fresh milk and 79 fermented milk (nono) were sampled from Kwale, Ozoro, and Oleh representing one senatorial district of Delta state, South-South Nigeria. They were screened for the presence of tylosin and other antimicrobial residues using four-plate test and tylosin was confirmed with high-performance liquid chromatography. Results: Antibiotic residues were obtained in 76% and 85% of fresh milk and nono, respectively. Tylosin residue was also detected in 24% fresh milk and 11% nono samples at mean concentrations of 14.64±0.69 μg/l and 7.97±0.23 μg/l, respectively. The mean concentrations of tylosin from both milk types were below the recommended maximum residue limit (MRL) of 50 μg/l in dairy. Conclusion: High prevalence of antimicrobial residues in fresh milk and nono shows that consumers in the study area are predisposed to health hazards due to the presence of residues of different antibiotics in fresh milk and nono. Although tylosin was confirmed in both milk products, the mean concentrations were below the MRL. However, it is still very vital to resort to the observance of withdrawal periods and avoid gross misuse of antimicrobials. It is also necessary to emphasize the need for effective prevention of infectious diseases and most importantly create awareness and establish a national antibiotic residue monitoring program in Nigeria

Immunologic determination of chloramphenicol residue in commercial birds at Nsukka, Enugu State, Southeast Nigeria

Aim: This study aimed to determine the presence and prevalence of chloramphenicol (CAP, a drug which was banned for use in food-producing animals due to many side effects) residue in commercial birds slaughtered at Ikpa abattoir and its awareness and usage in farms at Nsukka, Enugu State, Nigeria. Materials and Methods: A cross-sectional survey was done with the use of a questionnaire on usage and awareness of CAP and screening for its presence in commercial poultry in the study area. The questionnaire was supplied to 35 commercial farms, and liver samples from 300 commercial broilers were analyzed using an enzyme-linked immunosorbent assay technique; the prevalence was then determined. Results: Of the 35 farms evaluated, 33 (94%) responded. In the management practice, 57.6% of the farms use intensive deep litter, 18.2% intensive battery cage, and 24.2% extensive farming system. 19 (69.7%) farms rear only broilers, 12.1% layers, and 15.1% both. The feeding management showed that 21.1% of farmers produce their own feed with inclusion of antibiotics while 78.8% use commercial feed, of which 11.5% incorporate antibiotics. The findings also showed that 54.4% of the respondents use CAP and only 30.3% are aware of the consequences of antimicrobial residue in food and have knowledge of the legislation on the prudent use of antimicrobials in food animals. Of the 300 samples screened for CAP residue, 18.7% were positive with concentrations ranging from 0.5 to 6.2 parts per billion. Conclusion: CAP is still very much in use in the study area, despite the ban, and it is present in the tissues of commercial birds meant for human consumption

Slaughter of pregnant goats for meat at Nsukka slaughterhouse and its economic implications: A public health concern

Aim: This study was conducted to determine the incidence rate of the slaughter of pregnant goats in Nsukka slaughterhouse, which has become a major cruel occurrence in Nigeria, as well as it's economic and public health implications. Materials and Methods: All the goats slaughtered at Nsukka slaughterhouse over a period of 3 months (February-April, 2017) were screened. The data collected were: total number of goats slaughtered, age, breed and sex of goats slaughtered, pregnancy status of the goats, and sex of the fetuses observed, and gestational age of the fetuses estimated by crown-rump length. Results: In the 3-month study, a total of 684 goats were slaughtered, of which 617 (90.2%) were females. 364 (59%) of the females slaughtered were pregnant, and more than 80% of the gestations were in the second and third trimesters. Of 661 fetuses recorded, 320 (48.3%) were males, and 341 (51.7%) were females with 438 (66.3%) predominantly twins. At the cost of ₦ 6,000 ($16) and ₦ 8,000 ($20) for male and female kids, respectively, a total of ₦ 4,648,000 ($11,620) was lost in just one slaughterhouse in 3 months. Conclusion: This study shows that there is a high rate of slaughter of pregnant goats in Nsukka slaughterhouse with a tremendous economic loss, and most chevon sold in Nsukka are unwholesome and of low meat quality

<i>Staphylococcus aureus</i> in Horses in Nigeria: Occurrence, Antimicrobial, Methicillin and Heavy Metal Resistance and Virulence Potentials

Staphylococcus aureus was isolated from a total of 360 nasal and groin skin swabs from 180 systematic randomly-selected horses slaughtered for meat at Obollo-Afor, Enugu State, Southeast Nigeria and antimicrobial, methicillin and heavy metal resistance profile and virulence potentials of the isolates established. Baird-Parker agar with egg yolk tellurite was used for S. aureus isolation. S. aureus isolates were confirmed biochemically and serologically using a specific S. aureus Staphytect Plus™ latex agglutination test kit. The antimicrobial resistance profile, methicillin, vancomycin and inducible clindamycin resistance, and β-lactamase production of the isolates were determined with disc diffusion. Tolerance to Copper, Cadmium, Lead and Zinc was assessed using the agar dilution method and virulence potentials were determined using phenotypic methods. Forty-three (23.9%) of the 180 horses harbored S. aureus. Some 71 S. aureus were recovered from the 360 samples. Two (2.8%) of the 71 S. aureus were methicillin-resistant S. aureus (MRSA) and 69 (97.2%) were methicillin-susceptible. MRSA was recovered from 2 (1.1%) of the 180 horses. Some 9.4% of the isolates were multiple drug-resistant (MDR). The mean multiple antibiotic resistance indices (MARI) for the isolates was 0.24. Heavy metal resistance rate of the isolates ranged between 35.4–70.4%. The isolates, including the MRSA strains, displayed virulence potentials as clumping factor and catalase, gelatinase, caseinase, heamolysin, and biofilm was at the rate of 100%, 53.5%, 43.7%, 18.3% and 23.9%, respectively. This study showed that a considerable percentage of horses slaughtered in Obollo-Afor Southeastern Nigeria are potential reservoirs of virulent multiple drug- and heavy metal-resistant S. aureus, including MRSA, that could spread to humans and the environment

Staphylococcus aureus in Horses in Nigeria: Occurrence, Antimicrobial, Methicillin and Heavy Metal Resistance and Virulence Potentials

Staphylococcus&nbsp;aureus was isolated from a total of 360 nasal and groin skin swabs from 180 systematic randomly-selected horses slaughtered for meat at Obollo-Afor, Enugu State, Southeast Nigeria and antimicrobial, methicillin and heavy metal resistance profile and virulence potentials of the isolates established. Baird-Parker agar with egg yolk tellurite was used for S. aureus isolation. S. aureus isolates were confirmed biochemically and serologically using a specific S. aureus Staphytect Plus&trade; latex agglutination test kit. The antimicrobial resistance profile, methicillin, vancomycin and inducible clindamycin resistance, and &beta;-lactamase production of the isolates were determined with disc diffusion. Tolerance to Copper, Cadmium, Lead and Zinc was assessed using the agar dilution method and virulence potentials were determined using phenotypic methods. Forty-three (23.9%) of the 180 horses harbored S. aureus. Some 71 S. aureus were recovered from the 360 samples. Two (2.8%) of the 71 S. aureus were methicillin-resistant S. aureus (MRSA) and 69 (97.2%) were methicillin-susceptible. MRSA was recovered from 2 (1.1%) of the 180 horses. Some 9.4% of the isolates were multiple drug-resistant (MDR). The mean multiple antibiotic resistance indices (MARI) for the isolates was 0.24. Heavy metal resistance rate of the isolates ranged between 35.4&ndash;70.4%. The isolates, including the MRSA strains, displayed virulence potentials as clumping factor and catalase, gelatinase, caseinase, heamolysin, and biofilm was at the rate of 100%, 53.5%, 43.7%, 18.3% and 23.9%, respectively. This study showed that a considerable percentage of horses slaughtered in Obollo-Afor Southeastern Nigeria are potential reservoirs of virulent multiple drug- and heavy metal-resistant S. aureus, including MRSA, that could spread to humans and the environment

Occurrence and antibiogram of Listeria species in raw pork, beef, and chicken meats marketed in Enugu State, Southeast Nigeria

Aim: This study was undertaken to isolate Listeria (L.) species from raw meats sold in markets in Enugu State, Southeast Nigeria, and to determine the antibacterial resistance profile. Materials and Methods: Twenty-five grains of beef (n=144). chicken meat (n=144), and pork (n=144) were collected randomly from supermarkets and general markets in Enugu State. Isolation of Listeria was done using half and full Fraser broths, and polymyxin acriflavine lithium chloride ceftazidime aesculin mannitol agar. Identification of isolates was done using an analytical profile index kit specific for Listeria. Confirmation of the genus Listeria was done by a polymerase chain reaction. The resistance of the isolates was determined using the disk diffusion method. Results: Listeria was isolated from 39/144 (27.1%) chicken meat, 19/144 (13.2%) pork, and 66/144 (45.8%) beef samples cultured. Listeria innocea was the predominant species in chicken meat (52.6%) and beef (81.8%) samples. Listeria grayi, Listeria welshimeri, and Listeria ivanovii were also isolated from the beef and chicken meat samples. More than 65% of the isolates were resistant to penicillin, rifampicin. ciprofloxacin, sulfamethoxazole-trimethoprim, and cephalothin. All the isolates from beef and pork samples and 23 (92%) from chicken meat samples, were resistant to >= 3 classes of antibacterial agents. Mean multiple antibiotic resistance index (MARI) was 0.77 (range=0.42-1.00). 0.58 (range=0.25-0.83), and 0.79 (range=0.58-0.92) for the isolates from beef. chicken meat. and pork samples, respectively. All the isolates had MARI >0.2. Conclusion: Multidrug-resistant Listeria strains contaminate raw beef, pork, and chicken meats marketed in Enugu State, Southeast Nigeria.TETfund through the University of Nigeria (Institutional based research - IBR) TETfund TETFUND/DESS/UNN/NSUKKA/RP/VOL.V Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT) CONICYT FONDECYT 116116