Boron profile in common feedstuffs used in tropical livestock systems

In the scenario of increased reports on boron (B) supplementation in animal diets for beneficial effects, there is inadequate information on B content of animal feeds. The present study was carried out to quantify the level of B in animal feeds commonly used in tropical feeding systems. Samples of a total of 225 feeds were procured. The feed samples were oven dried, ground to 1 mm size and wet digested, filtered using Whatman filter paper (no 42) and volume made up to 100 ml by deionized water. Boron (B) content was estimated using inductively coupled plasma optical emission spectroscopy (ICP-OES). The level of B in fibrous feeds (n = 83) was higher than in concentrate feeds (n = 120) and unconventional feeds (n = 22). The range of B content among the feed samples analyzed (n = 225) showed a wide range from rice bran to cowpea fodder (0.69–59.1 mg/kg). The spatial distribution of B indicates that most feed samples analyzed showed B content lower than 20 mg/kg with mean and median of 17.7 ± 0.96 and 14.4, respectively. It is evident from the present study that appreciable quantity of B is detected in all the major categories of feedstuffs which was comparable to the levels of essential trace elements like copper and zinc. These findings would facilitate in assessing the supplementary value of tropical feeds for boron.