Oxytetracycline and penicillin-G residues in cattle slaughtered in south-western Nigeria: Implications for livestock disease management and public health

Abstract

After the discovery of indiscriminate antibiotic use in ready-for-slaughter cattle in south-western Nigeria, 90 tissue samples from randomly selected slaughtered cattle were evaluated for oxytetracycline and penicillin-G residues using high performance liquid chromatography and the data analysed by one-way Analysis of variance (ANOVA). The findings revealed residues of oxytetracycline (kidney: 9.47 µ/kg ± 3.24 µ/kg; liver: 12.73 µ/kg ± 4.39 µ/kg; muscle: 16.17 µ/kg ± 5.52 µ/kg) and penicillin-G (kidney: 6.27 µ/kg ± 2.46 µ/kg; liver: 8.5 µ/kg ± 2.80 µ/kg; muscle: 11.67 µ/kg ± 2.94 µ/kg) in all tissues screened. Significantly high levels (oxytetracycline: F = 16.77; penicillin-G: F = 29.38) were, however, found in muscles, followed by liver and then kidney – findings confirming recent antibiotic administration to the animals before slaughter. The dietary intakes through the tissues screened were 0.024% (oxytetracycline) and 0.017% (penicillin-G) of the acceptable daily intake (ADI). Although the concentrations in the tissues screened were below the maximum residue limits despite recent administration of these antibiotics before slaughter, the lower concentrations are suggestive of the probable low dosages often administered by those involved in indiscriminate use of antibiotics. This therefore raises serious concerns for the livestock industry as well as human health, given the resultant emergence and spread of resistant strains of bacterial pathogens that could ensue from prolonged use of low dosages of antibiotics. Additionally, the lower concentrations of the daily intakes notwithstanding, the plausible exposure to these antibiotics from other food sources is a cause for concern. Since antimicrobial misuse and its consequent effects are not just a problem limited to Nigeria but also a concern in sub-Saharan Africa, the need for national and international stakeholder intervention is emphasised.

Antimicrobial Resistance in Food Animals and the Environment in Nigeria: A Review

“…The 80 studies excluded did not directly relate to the objectives or yielded information that could be subjected to organized peer review and data analysis. The 59 included studies were sorted into three categories of 42 antimicrobial resistance studies [14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55], 16 antimicrobial residue studies [56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71], and 1 antiseptic or disinfectants study [72]. The PRISMA-style flowchart was modified and used for this analytical review (Figure S1) [73].…”

Occurrence and antibiogram of <i>Staphylococcus aureus</i> in dairy products consumed in parts of Kaduna State, Nigeria

“…The residues of antibiotics have also been reported in tissues of food animals and their products (Kabir et al 2004;Adesokan et al 2013). The high percentage occurrence of multiple antibiotics resistance (MAR) index (64.29%) among the S. aureus isolates might have arisen due to common practices such as self medication and over the counter usage of antibiotics.…”

Penicillin-G and oxytetracycline residues in beef sold for human consumption in Maroua, Cameroon

“…This could be attributed to the probably low doses of antimicrobials commonly administered by pastoralists in order to maximize the number of doses available (Olatoye and Ehinmowo, 2009). This concentration is higher than that obtained in beef consumed in the southwestern Nigeria (8.81 μg/kg) (Adesokan et al 2013).…”

“…Though lower than MRL, presence of residues highlights once again the misuse of drugs in the Far North region of Cameroon (Vougat et al 2017) and the need to solve this public health problem. The concentration of 240 μg/kg is, however, significantly higher than that obtained in the South-West of Nigeria (12.79 μg/kg) by Adesokan et al (2013). This shows the high level of contamination in this study zone and also in Nigeria where, all the samples analyzed contained the residues of this antibiotic.…”

“…This high percentage of contaminated beef could also have an impact on beef trade (Olatoye and Ehinmowo, 2009). The proportion of contamination (20.30%) is however smaller less than that obtained by Adesokan et al (2013), Olatoye and Ogundipe (2009) and Olatoye and Ehinmowo (2009) in their analysis of the cattle samples collected in different slaughterhouses in several cities in Nigeria. Indeed, they obtained percentages of contamination of 100, 40 and 54.44% respectively.…”