Journal de médecine vétérinaire et de santé

Abstrait

Bacterial Bovine Mastitis and Formation of Specific antibodies in Milk and Sera, Sudan

Suliman RM and Salih RR

The aim of the study to isolate and identify the bacteria which can cause mastitis in cows and the antibodies forming during the infection by these bacteria and appear in milk and serum. A total of 50 samples of milk were collected from all quarters of each cow and sera were collected from cows with clinical and subclinical mastitis in two different farms in Khartoum. The bacteria were isolated from 38 (76%) of the milk samples and the total number of isolates was 45. Sixteen (36%) bacterial isolates were obtained from cows with clinical mastitis, whereas 29 (64%) were obtained from cows with sub-clinical mastitis. Mixed infection was detected in 10 (20%) of the milk samples. Both Gram positive and Gram negative bacteria were isolated and identified to the species level, using cultural characteristics and biochemical tests. Most isolates were Staphylococcus species, other gram positive bacteria isolates: 1: Streptococcus agalactiae, 3 species from Enterococcus (avium, mundtii and faecium), 2: Listeria Ivanovii, 3: Bacillus species (two Bacillus licheniformis and one B. mycoides) and 3 strains of Corynebacterium pseudotuberculosis. The gram negative bacterial isolates: three Enterobacteria species (2: Citrobacter freundii and 1: Klebsiella pneumoniae and Pseudomonas aeruginosa consisted two strains. Only Bacillus mycoides gave clear precipitation lines with both milk immunoglobulin fraction and serum. Other bacteria gave precipitation lines with serum antibodies alone. The results revealed that the Gram positive bacteria, especially Staphylococcus species, were the common causative agent of bovine mastitis; the number of cows with subclinical mastitis was higher than cows with clinical mastitis. The bacteria associated with bovine mastitis can induce local and systemic specific antibodies response as measured by agar gel immuno-diffusion test.