An Assessment of Cattle Feed and Milk for Selected Contaminants and Examination of Health Impacts Among Consumers

Abstract

Milk and its derivatives include one of the essential constituents of the human diet, mainly because of the mineral, vitamins, and protein contributions in a balanced proportion. Therefore, the contamination of milk by heavy metals and microorganisms can pose a serious public health problem due to the different health conditions and diseases among consumers, especially in children. Slum livestock farming is a way for slum residents to obtain food, make money, and support their way of life. People in slums sell the animal products they obtain to fulfil their needs. A valuable product that helps ensure food security in slums is milk. Along the dairy value chain, there is insufficient information on milk handling, quality evaluation, and marketing linkages. However, most marketplaces are unregulated, there is a higher risk of microbial and chemical contamination. Therefore, this study was conducted to investigate and evaluate the dairy cattle feed and milk for selected biological and chemical contaminants as well as the risks associated with them along the dairy value chains in H-11/4 slums. Through bacteriological plating, the study specifically investigated the presence of microbes in the milk and feed. Fifteen (15) major and minor elements were also examined using inductive coupled Plasma optical emission spectroscopy analysis (ICP-OES). Nitrates and phosphates were assessed in cattle feed and milk through UV visible spectrophotometric method. A total of eight milk and eight feed samples from four dairy farms were assessed for microbial contamination by using total plate count (TPC), coliform plate count (CPC), and SS plate count (SSPC), all twelve samples showed high number of coliforms, total bacteria, and Salmonella shigella microbial species. In addition to these, worms and fungus in some milk and feed samples were also seen, which makes it noticeably clear that the quality of the milk was unsatisfactory and poor. The mean CPC was found to be 6.58 (logl0 cfu'ml) with more counts recorded in site 3 and 4 which ranged from 5.80 to 7.36 (logl0 cfw/ml). The mean TPC was 6.25 log10 cfu/ml with more counts reported in site 3 and 4 from dairy farms ranging from 5.57 to 6.93 logl0 cfw/ml. The results showed a mean SS count of S.04 log10 cfu/ml with more counts reported in site 2 and 3 from dairy farns ranging from 3.68 to 6.40 log10 cfu/ml. The results showed a mean nitrate value of l1.83 mgL for milk samples, 11.67 mg/. for dry feed and 12.22 mgl. for wet feed samples from dairy farms. Similarly, the mean values of sulphates for milk samples were 24.3 mgl, 27.02 mg/l for dry feed and 15.39 mg/l. for wet focd samples. The concentrations of K, Sr, were increasingly high in all milk samples, whereas the concentrations of Al, Se, Ba, and Cu varied in all milk samples. Other elements had very low or negligible levels in milk. Poor hygiene and sanitation during milking and post-milking activities are indicated by the presence of higher amounts of pathogenic microorganisms and certain metals in milk., as well as prominent levels of pollution in the environment, which will have an impact on milk, and milk products produced by the animals. The milk shows indicators of poor hygiene and points to a potential source of milk-borne illnesses. Dairy farmers and people who have kept animals for milk should take care of the cleanliness of the animal, and hygiene practices in milk production, handling, storage, and delivery processes to avoid the contamination of milk.