Efficacy of Newly Developed Screening Test (D-Saft1) For Detection of Antibiotic Residues in Raw Milk Samples Collected from Khartoum State, Sudan

Aim: In this study a newly antibiotic screening test (D-SAFT1) was developed, it is based on activation of Lactobacillus casi (DSM 38124) embedded in dried milk particles.

Methods: For the preparation of the test mixture: powdered milk, lactose, standard bromocerol green indicator solution and 0.1 ml of 1.5 × 107 Lactobacillus casei MRS culture were added to each Universal bottles containing specific amount of antibiotic standard. The mixtures were frozen in a deep freezer at -200C for 24 hours. Then the bottles were lyophilized (–600C) and kept at 4-50C until used. Field samples of raw milk (200 cows, 50 camels and 50 goats) were collected from Khartoum State and examined for antibiotic residues using D-SAFT1 against two other approved methods that include Trisensor antibiotic test and the Modified One Plate Test.

Results: Tri sensor, Modified one plate test and the new detection method (D-SAFT1) revealed the same results that 80 (40%) of cow milk samples were positive to antibiotics residues, while all camel and goat milk samples were negative.

Conclusion: The antibiotic new detection method should be looked upon as an alternative screening method by encouraging its improvement, use and application as a field test, this especially because it can be prepared locally in addition to its low cost.