The effect of management practices on the hygienic quality of raw milk produced by some dairy Farms in Khartoum State

This study includes current dairy management and husbandry practices in 60 dairy farms at different locations in Khartoum, Khartoum North and Omdurman of Khartoum State (20 farms from each town), to evaluate their practices of dairy farming. It was also aimed to know the constrains and to identify the weakness that need correction. Information about dairy management was collected by questionnaire and direct interview with farms' owners. Moreover, this study was also aimed to evaluate the quality of raw milk produced by these farms. To achieve the objective of hygiene, 120 milk samples were collected from the selected 60 dairy farms and tested during summer and winter seasons. The study of chemical composition (total solids, lactose, protein, fat, ash, acidity, freezing point, temperature and pH) and some microbial hazards (Brucella , E. coli, Staphylococcus aureus, Staphylococcus spp. and Salmonella spp.), were carried out. Laboratory pasteurization counts, coliforms counts, Enterobacteriaceae counts and total bacteria counts associated with raw milk were estimated. Enumeration, isolation and identification of S. aureus, E. coli, Salmonella spp. and the presence of Brucella were also estimated. The results indicated that there were significant differences in education levels of dairy farms' owners. Khartoum dairy farms' owners' exhibit higher illiteracy level (35%), Khartoum North (15%) and Omdurman (30%). Significant differences (P < 0.05) were obtained in herd size and herd structure. Moreover, dairy herd numbers were 170.25± 72.83, 123.10± 105.71 and 92.35± 29.23 in Khartoum North, Khartoum and Omdurman, respectively. Breed type revealed non-significant differences between the three cities. However, 92% of the cattle in the studied farms were grade cattle and mainly they were of unknown foreign blood percentages. Ideal building materials, health set up, design and different management practices rarely practiced in Khartoum dairy farms and they were only restricted to 9 farms (45%) in Khartoum and 6 farms (30%) in Khartoum North. Corrugated iron roof and concrete flour were reported to be very rare. The same was true for using machine milking and mastitis prevention practices such as strip cup dip and teat dipping as they were reported among three of the studied farms. Concerning the health services and preventive measures, the diseases control were not satisfactory, only 10% of the studied dairy farms had resident veterinarian. Vaccinations against diseases were rarely used in regular way. General hygiene and sanitation measures such as dung removal, disinfection, cleaning program and maintaining minimal contamination during milking process could not be observed in the majority of dairy farms; studied except for few farms in Khartoum (20%) and Khartoum North (10%). Also disposal of abnormal milk were applied directly in the pens in 83% of the farms. Moreover, testing, isolation and culling practices were not common. The highest numbers of aborted cows at late pregnancy were showed in 1-16 dairy farms in Khartoum. Similarly mastitis, which was found in 14 farms, in Khartoum and the cases ranged from 1–5 cases. On the other hand laboratory tests were carried out for milk samples obtanied from the dairy farms. The results indicated that there were significant differences in temperature and freezing point (P< 0.05) between seasons. The result of fat, protein and ash content of milk samples revealed non-significant differences (P> 0.05) between seasons and between cities. Lactose was found to be significant (P< 0.01) when comparing the interaction between seasons and cities. Total solids content of milk samples revealed significant differences (P< 0.01) between cities and nonsignificant differences (P< 0.05) between seasons and their interaction.. Brucella antibodies were detected in 104 out of 120 milk samples. Fifty (83.33%) and 54 (90%) of the milk samples were positive during summer season and winter, respectively. Highly significant variations (P< 0.01) were reported for the milk samples collected from dairy farms in Khartoum for means of acidity, total bacterial counts, laboratory pasteurization counts, Staphylococcus spp. counts, Enterobacteriaceae counts and coliforms counts were compared for the three cities. However, highly significant differences (P< 0.05) were found in total solids of milk from Omdurman's dairy farms than other two cities