Effects of levels of threonine and a phytogenic additive in the diets on the performance and gut health of chickens challenged with Eimeria spp

Abstract

The study of the relationship between the additives and nutrients is essential for improving the use of these substances and the maximum animal performance. The purpose of this study is to examine the effects of levels of threonine and the inclusion of blends of essential oils on the performance and intestinal health (morphology, intestinal microbiota and mucin production) in broilers challenged with Eimeria spp. The treatments will follow a 3x2 factorial arrangement with three levels of digestible threonine (100, 110,120% of recommendations), and supplementation or not of a blend of essential oils in the feed in a completely randomized design experiment. The diets based on corn and soybean meal to meet the nutritional requirements will be fed ad libitum. Each treatment will have six replicates of 40 birds each, totaling 1440 animals. At seven days of age, all birds will be challenged with Eimeria spp. in the drinking water. Performance will be evaluated weekly until 42 days of age. At 21 and 42 days of age, samples of the intestines will be collected for morphometry and goblet cells. At 42 days of age, samples of the contents of the small intestine and the cecum will be collected for analysis of microorganisms and contents of the ileum will be collected for determining the mucin production. The data will be submitted to analysis of variance at 5%, studying the interaction and the effects of the main factors. (AU)