Nutrition of Zebu Cattle in Northern Nigeria 2. The Importance of Carotene Supplements

Abstract

The importance of carotene supplements in the feeding of White Fulani Zebu cattle has been studied in three experiments. The live weight gains of heifers, with and without carotene on two planes of nutrition, showed c 2 lb/head/day gain on the 'high' plane, but the 'low' plane group did not respond to carotene supplement. The association between cottonseed feeding and vitamin A deficiency, studied by comparing the rates of depletion of heifer calves on cottonseed supplements and on a sorghum/groundnut mixture, indicated that cottonseed can enhance the rate of carotene/vitamin A depletion in the liver. Carotene supplements equivalent to 2 02 red palm oil, to cows before and after calving failed to improve the vitamin A potency of milk. The total daily secretion of carotene and vitamin A in the milk was insufficient to maintain adequate liver stores in a suckled calf. The effects of dry season feeding on vitamin A and carotene depletion in growing cattle have been demonstrated (Miller, i960 and 1961), and it has been shown that feeding carotene supplements can result in an increased rate of live weight gain when the ration contains adequate energy and protein. On a moderate plane of nutrition, it was also found that the liver storage of carotene during the wet season was sufficient to sustain the animal over a period of six months on a carotene-free diet.Although the period during which cattle may be expected to subsist on a carotene-free diet is unlikely to exceed six months, it was desirable to obtain further information on the effects of certain husbandry practices which were likely to affect the rate of depletion of carotene and vitamin A in the animal. Reports in the literature (Church el al., 1956) have shown that an increased plane of nutrition may enhance the rate of depletion, but from the viewpoint of increasing production, it is perhaps more important to determine whether there is any beneficial effect of feeding a carotene supplement to animals on an increased plane of nutrition. Flora et al. (1939) found that calves fed with high levels of cottonseed meal exhibited symptoms which corresponded closely with those of animals on a ration deficient in vitamin A, but the symptoms cleared up with administration of a carotene concentrate. Such a finding could have considerable practical significance in Northern Nigeria, where whole cottonseed is fed in varying amounts to young cattle as a dry season supplement.The effect of feeding low carotene rations to lactating cows through its effects on the vitamin A potency of milk fat, may determine the vitamin A nutrition of * Present address: North of Scotland College of Agriculture, Aberdeen, t Deceased.

Seasonal production of Andropogon gayanus. I. Seasonal changes in yield components and chemical composition

“…The present results have demonstrated the value of leaves as a source of carotene, which Miller & Iduma (1967) have shown to be necessary for normal animal growth. The importance of leaves as a source of calcium and phosphorus is also apparent since at all stages of growth the leaves contained a higher proportion of these two elements compared with the stems.…”

Forage Conservation in the Tropics*

“…In that it reduces the carotene content of the crop. Carotene and vitamin A depletion can be a serious limiting factor in impairing animal production at high levels of feeding, but normal levels of production are not affected to any measurable extent (3). Perhaps the main advantage of wilting is that it prevents effluent loss.…”