Screening for Antibiotic Residues in Milk of Cattle and Sheep in Khartoum and AL-Gezira States

Abstract

This study was conducted in Sudan between November, 2017 and April, 2018 to assess the antibiotic residues in raw milk produced by small-scale dairy farms and local markets selling milks in the area, as these residues may have a negative impact on human’s health. Fifty small-scale dairy farmers and sellers were involved.Fifty milk samples were randomly collected in douplicate ;meaning 2 samples from each animal to only one of them ,the Sodium azide was added as a long time sample preservative for future researches. The study involved Aljazeera state and three localities in Khartoum state which are East-nile, Al-khartoum and Omdurman . Laboratory assessment included, screening qualitative test using inhibitory activityand the micro-biological methods in which all Samples were tested for the presence of residues of antibiotics .A strain of bacteria Bacillus subtilis was used and cultured in agar mediaand the milk samples were placed on cavities of the agar .A milk sample-impregnated whatman's filter paper was used in another method. Chi- square test was used for comparison between different localities , between farms and markets samples and between cattle and sheep at 5% probability level ;to determine the percentage of antibiotic residues. Out of the fifty milk sample 3(6%)were positive for antibiotic residues.Two of these positives samples were bought from the markets in Omdurman locality while the third one was obtained from a farm within the same locality. The study Recommends a further screening for residues at the milk collection centers and investigation of the milk production practices among small-scale dairy farmers. This will provide a standing ground for designing appropriate and effective small scale milk production practices which will reduce milk contamination and help to protect the health of consumers in Sudan.