| dc.description.abstract | Sulfonamides are some of the most widely used antibiotics in the world for human and veterinary purposes. In poultry, sulfadimidine is widely used for the treatment of coccidiosis in laying hens at the dose of 2 gil for 6 consecutive days via drinking water. There is concern that the residues of this drug may be retained in the eggs and present a potential risk to human health. The study aimed at assessing the levels of sulfadimidine residues in eggs sold in Nairobi; compare these levels with the world health organization/food and agriculture organization acceptable maximum residue limit of 1 OOug/kg and find out the impact of farming systems on the levels of sulfadimidine residues in eggs. Eighty eggs were randomly sampled from Nakumatt supermarket and Kariokor market within Nairobi. Forty were from commercial hens sampled from Nakumatt supermarket and forty others were from free range hens sampled at Kariokor market.
Whole egg samples were analyzed for sulfadimidine residues using a reversed phase high performance liquid chromatography technique following sample extraction and clean up. Sulfadimidine was extracted from whole eggs with acetonitrile and ethyl acetate and sample clean up achieved using a combination of n-hexane, acetonitrile and acetate buffer as the mobile phase. Sulfadimidine residues were detected by a reversed phase high performance liquid chromatography using ultraviolet-visible (uv-vis) detector at a wavelength of 27Snm. The separation was performed on a Lunafium CI8 (2)-100A, column (IS0x4.6mm) and the best separation of sulfadimidine was achieved using an acetonitrile-acetate buffer (PH 4.6) (30:70, v/v) as the mobile phase. Sulfadimidine was successfully detected within 3.443 min, when the flow-rate was 1.0 mllmin. The limit of detection was 0.05mg/kg. In this study, there was a recovery of 79-87% with relative standard deviation values less than 10% for all samples.
The study found eighty five percent of the eggs sampled to have sulfadimidine residues below the established maximum residue limits of 1001lg/kg· Only two (2.5%) were free of sulfadimidine residues. The highest levels recorded were 1831lg/kg and 1531lg/g for eggs from commercial and free range hens respectively. Twelve (15%) were found to have sulfadimidine residues above the maximum residue levels recommended by codex alimentarius commission. The mean sulfadimidine residue level was 46.721l1kg which was lower than the established codex alimentarius commission maximum residue limits. A comparison of the means of the two groups of eggs {(commercial (35.7751lg/kg) versus free range hens (57.751lg/kg)) was significantly different (p<0.05). However, these were all below the recommended level of codex alimelltarius commission maximum residue limits for sulfadimidine in eggs. About 7.5% and 22.5% of eggs from commercial and free range hens respectively, were found to have sulfadimidine residue levels above the maximum residue limit of 1001l1kg.
The results indicate that eggs from free range hens had higher sulfadimidine residue levels compared to those from commercially raised hens. This disapproved the null hypothesis of the study that eggs from free range hens have lower antibiotic residue levels than those from commercially produced hens since free range hens are rarely treated with antibiotics. It is therefore recommended that periodic assessment of eggs and other foods of animal origin should be carried out to monitor antibiotic residue levels in order to minimize public health risk. | en_US |
