Discipline: stress; Keywords: antioxidant herbs, anti-oxidative status, immunity, Jersey cows, milk yield.
Vitamins, mostly A, C and E, and minerals, such as selenium, copper and zinc, have been used to mitigate oxidative stress. However, in confined systems, the risk of over- or undersupplying micro elements is high, hence the overproduction of pro-oxides is common. Additionally, in semi-intensive feeding systems, trace elements, particularly antioxidant supplementation, are limited owing to restricted or lack of supplementation. Therefore, research focus has shifted to exploration of the potential of natural antioxidants in improving animal production and health. Moringa oleifera is a natural herbal plant that is recognized for high leaf crude protein and is utilized in the diets of ruminants and fish. It is a rich source of natural antioxidants such as vitamin A (ß-carotene), vitamin B (folic acid), pyridoxine and nicotinic acid, vitamins C, D and E. In addition, M. oleifera leaf meal contains significant amounts of phenolic and flavonoids. These compounds have anti-oxidative and immune-modulatory properties that are more effective than most synthetic antioxidants. Because early lactating dairy cows are prone to oxidative stress, M. oleifera may serve as a natural and cheaper antioxidant source in resource limited-areas. Therefore, in the study of the authors cited below, the effects of micro-supplementing M. oleifera leaf meal on selected blood metabolites and the lactation performance of dairy cows raised in semi-arid conditions were evaluated.
Thirty Jersey cows (± 40 days in milk) were supplemented with M. oleifera leaf meal (M) at 0 (M0), 30 (M30) and 60 g per cow per day (M60). The experiment lasted until 90 days in milk with 14 days adaptation. Milk yield was recorded daily and samples were collected once weekly to determine milk composition and total antioxidant capacity. Blood samples were collected on days 54, 68 and 90 in milk to determine serum total protein, albumin, immuno-globulin G and serum total antioxidant capacity.
Body weight and milk yield were not affected by Moringa supplementation. Moringa supplementation at M60 increased milk fat and total antioxidant capacity with a significant reduction in somatic cell count. Increased total serum protein and immune-globulin with reduced non-esterified fatty acid levels were observed in M60. Increased serum total antioxidant capacity levels were noted in all groups supplemented with Moringa.
It was concluded that by supplementing Moringa oleifera leaf meal to lactating Jersey cows at 60 g per cow per day stimulated blood energy-related metabolites and serum antioxidant capacity, consequently improving milk quality with an associated reduction in oxidative stress.
T.W. Kekana, U. Marume, C.M. Muya & F.V. Nherera-Chokuda, 2019. Lactation performance and blood metabolites in lactating dairy cows micro-supplemented with Moringa oleifera leaf meal. S.Afr. J. Anim. Sci. 49, 710 – 716.