Responses of broiler chickens to Eimeria challenge when fed a nucleotide-rich yeast extract

Abstract

Nucleotide-rich yeast extract (YN) was investigated for effects on growth performance, jejunal physiology, and cecal microbial activity in Eimeria-challenged broiler chickens. A total of 360-day-old male chicks (Ross × Ross 708) were placed on floor pens and provided a corn–soybean meal-based diet without or with YN (500 g/MT; n = 12). On d 10, 6 replicates per diet were orally administered with 1 mL of E. acervulina and E. maxima sporulated oocysts and the rest (non-challenged control) were administered with 1 mL of distilled water. On d 15, 5 birds/pen were then necropsied for intestinal lesion scores, histomorphology and cecal digesta pH, short chain fatty acids (SCFA), and microbial community using Illumina Miseq platform. Supplemental YN improved (P = 0.01) Feed conversion ratio (FCR) during the prechallenge phase (d 0 to 10). In the postchallenge period (d 11 to 15), Eimeria depressed (P < 0.05) Body weight gain (BWG) relative to non-challenged birds, whereas YN-fed birds had a higher (P = 0.05) BWG compared to that of non-YN-fed birds. There was an interaction between YN and Eimeria on jejunal villi height (VH) (P = 0.001) and expression of cationic amino acid transporter 1(CAT1) (P = 0.04). Specifically, in the absence of Eimeria, YN-fed birds had a shorter VH (892 vs. 1,020 μm) relative to that of control but longer VH (533 vs. 447 μm) in the presence of Eimeria. With respect to CAT1, YN-fed birds had a higher (1.65 vs. 0.78) expression when subjected to Eimeria than when not challenged. Independently, Eimeria decreased (P < 0.01) the jejunal expression of maltase, Na glucose transporter 1 and occludin genes, ceca digesta abundance of genus Clostridium cluster XlVa and Oscillibacter but increased (P < 0.01) jejunal proliferating cell nuclear antigen and interleukin 10. Interaction between YN and Eimeria was observed for ceca digesta pH (P = 0.04) and total SCFA (P = 0.01) such that YN increased SCFA in the absence of Eimeria but reduced SCFA and increased pH in the presence of Eimeria. In summary, Eimeria impaired performance and gut function and shifted gut microbiome; YN improved performance independently, attenuated Eimeria damage on indices of gut function, and modulated cecal microbiome.

Utility of Feed Enzymes and Yeast Derivatives in Ameliorating Deleterious Effects of Coccidiosis on Intestinal Health and Function in Broiler Chickens

“…The failure of parasitized animals to grow is partially due to loss of appetite and nutrient malabsorption (84,86,(92)(93)(94). Structural and functional damages to the small intestine are indicated by the histomorphology, digestive enzymes, nutrients transporters, and nutrient retention in our model (84,86,87). Moreover, E. acervulina and E. maxima infection down regulates expression of digestive enzymes and nutrient transporters (84,87,(93)(94)(95).…”

“…Our laboratory has developed a model to examine effects of coccidiosis on digestion and absorptive capacities and subsequent effects on GIT ecology. The rationale is to use this infection model to test dietary strategies during acute phase and recovery phases (84)(85)(86)(87)(88). The general approach is to challenge sub-samples of birds in a pen with high dose (100,000 E. acervullina and 60,000 E. maxima sporulated oocysts) to generate macroscopic lesions and the rest of birds with a low dose (25,000 E. acervulina and 5,000 E. maxima sporulated oocysts) in order to examine the consequences of altered nutrient digestion and absorption.…”

“…Structural and functional damages to the small intestine are indicated by the histomorphology, digestive enzymes, nutrients transporters, and nutrient retention in our model (84,86,87). Moreover, E. acervulina and E. maxima infection down regulates expression of digestive enzymes and nutrient transporters (84,87,(93)(94)(95). Subsequent sections will evaluate literature where coccidiosis challenge was used to evaluate impact feed enzymes and yeast derivatives in modulating the expression of coccidiosis.…”

“…Coccidiosis effectively reduces nutrients digestion and absorption linked to anorexia in concurrence with morphological and functional intestinal damage (Figure 2) (84,86,87). Increased mucogenesis and enterocyte turnover (84), as well as postabsorptive metabolic changes and immune system activation, likely influence nutrient needs of broilers (9).…”

“…These conditions are commensurate to gastrointestinal damage occasioned by Eimeria infection (9). Evaluations of nucleotide rich yeast extracts on growth, feed efficiency and intestinal development and health has been reported in broiler chickens (86,87,135,136). However, there are limited studies assessing the effects of dietary nucleotide supplementation on development of immune organs in broilers challenged with Eimeria.…”