Experimental Studies in Rats on the Effects on Growth and Intestinal Microflora of a New Mix Combining Calcium, Iron, Zinc and a Prebiotic in a Milk-like Vehicle

The aim of this work was to determine the effects of a new mineral mix combined with a prebiotic on growth, mineral deposit and intestinal microflora using a milk-like vehicle. This study was performed with Sprague Dawley female rats separated into 7 groups. Group 1 was fed with a deficient diet on its mineral content, group 2, 3 and 4 were fed with normal diets on their mineral content during 28 days but group 2 was fed with a diet containing reference Ca, Fe and Zn sources and groups 3 and 4 with diets containing other Ca, Fe and Zn sources that were evaluated. Group 4 received additionally a diet containing a prebiotic. Groups 5, 6 and 7 were submitted to a depletion period of 14 days during which they were fed as group 1 and then to a repletion period of 14 days when they were fed with the same diets as group 2, 3 and 4 respectively. Initial and final body weight, average growth rate, liver and femur weight, iron and zinc liver content as well as calcium and zinc femur content were the parameters evaluated for the growth and mineral deposit analysis. Anaerobes, enterobacteria, lactobacilli and bifidobacteria recount was performed from feces samples collected on different treatment days. Mineral sources under study presented slightly better characteristics than the reference standard ones. Moreover, the combination with a prebiotic may produce some advantages related to mineral absorption and intestinal microflora composition as a bifidogenic effect was confirmed.