Assessment of sulphonamides and tetracyclines antibiotic residue contaminants in rural and peri urban dairy value chains in Kenya

Abstract

Background: Antibiotic residues are drug substances found in food from plants or animals initially exposed to antibiotics. In animal husbandry antibiotics have widely been used for the treatment of animal diseases. These residues have the ability to expose the public to serious health hazards. In Kenya drug residues have not only been related to lack of withdrawal periods but also to intentional addition to extend milk's shelf life. Results: The aim of this study was to investigate the occurrence of 13 veterinary drugs of tetracyclines and sulphonamides along the dairy sub value chain. The study was carried out in Nakuru County which is the leading milk producer in the country. A total of 229 samples were analysed from rural and 80 samples from peri-urban. These were collected from different nodes of the value chain; the farm, milk transporters and at the bulking centers between January 2014 and November 2015. Screening of samples was done by Charm II Blue -Yellow-test while confirmation was done by HPLC-UV for sulfachloropyradizine (SCL), sulfadiazine (SDZ), sulfadimidine (SMTZ), sulfaquinoxaline (SQ), sulfamerazine (SMR), sulfathiazole (STZ), sulfamethoxazole (SMX), sulfadoxin (SDOX), sulfadimethoxin (SDM), oxytetracycline (OTC), doxycycline hyclate (DC), chlortetracycline hydrochloride (CTC) and tetracycline hydrochloride (TC). In the rural 72 out of 229 (31.4%) samples were positive after screening while none of the samples confirmed the presence of tetracyclines after analysis with HPLC-UV. Sulphonamides confirmed after analysis with HPLC-UV were all above the EU MRL limits. In the peri urban 28.8% (23/80) of the samples were positive for antibiotic residues. Tetracyclines were not detected in confirmation while 60% of the positive samples were positive for sulphonamides out of which 71% were above the regulatory limits. Highest percentage of antibiotics was detected in rural farms (46.7%) and at peri urban bulking centers (50%). Conclusion: The study concluded that antibiotic residues along the dairy value chain are majorly from the farm due to lack of withdrawal periods followed by intentional addition along the value chain. Value chain actors should also be trained on ways of avoiding antibiotic residues from entering the dairy value chain to protect the public from health effects related to antibiotic residues.

Evaluation of residues of β-lactam, sulfonamide, tetracycline, quinolone, fluoroquinolone e pyrimidine in raw milk

“…Similar results were also reported by Bilandžić et al (2011), Rassouli et al (2014), Prado et al (2015). However, higher amounts of samples with antimicrobial residues were found by Aalipour et al (2015), Layada et al (2016), Orwa et al (2017), Rama et al (2017), Wang et al (2017), Khanal et al (2018).…”

Antibiotic Residues in Milk from Three Popular Kenyan Milk Vending Machines

“…Recently (2017), in nearby Nakuru County, 28.8% (23/80) of milk samples from peri-urban areas were positive for antibiotic residues. 16 Among our noncommercial samples (MVM + street vendor) in Eldoret, we observed 23.6% (13/55) positive.…”

“…In addition, with regard to tetracycline, the screening method sensitivity used here was at 50 ppb rather than 100 ppb (Table 1), and positive detections of tetracyclines in Kenyan milk by screening are not always substantiated after analytical laboratory evaluation. 16 It is noteworthy that no commercial samples tested positive using the SNAP screening methods.…”

Assessment of Raw Cow Milk Quality in Smallholder Dairy Farms in Pemba Island Zanzibar, Tanzania

“…Antibiotic residues in animal source food are the potential causes of antibiotic resistance in bacteria. Other studies elsewhere have also reported high levels of antimicrobial residues in milk [ 8 , 53 – 55 ]. The differences in antibiotic residue levels in milk may be due to different production and monitoring systems and laboratory analysis used in testing of the antimicrobial residues.…”