Effects of dietary red yeast (Sporidiobolus pararoseus) as a substitute for antibiotics on productive performance, egg quality, and small intestinal histology of laying hens

Abstract

Nowadays, the industrial poultry production has focused more on the safety of their products, especially the contaminants from feedstuffs, such as mycotoxin and pesticides etc., The residue from animal production using antibiotic as growth promoters (AGPs) may cause some problems of antimicrobial resistance (AMR) in human and animals. Red yeast (Sporidiobolus pararoseus) has a cell wall consist of B- glucan and manno-oligosaccharides, as well as pigments from carotenoids that may be suitable for using to substitute AGPs. Therefore, the objectives of this research were to study the effect of red yeast to substitute AGPs in laying hen diets on productive performance, egg quality, and small intestinal histology. A total of 576 heads of 22-wk- old laying hen were distributed into 6 groups as follows: control diet (CON), CON with antibiotic (AGP), and CON supplemented with red yeast 0.5 (RY0.5), 1.0 (RY1.0), 2.0 (RY2.0) and 4.0 g/kg of diet (RY4.0) respectively. The experiment was conducted for 38 weeks. The results showed that RY2.0 groups had significantly higher final body weight (P<0.001) compared with the others, but had no significantly compared with RY4.0 and AGP groups. The red yeast supplementation improved the egg shape index (P<0.05), haugh unit (P<0.001), and the yolk colour (P<0.05) as well as yolk cholesterol (P<0.001). The red yeast supplementation at 4.0 g/kg increased villus height and villus width in duodenal (P<0.05). Moreover, villus width no significant difference compared with the AGP. In laying hens fed red yeast on crypt depth, crypt area, and muscularis mucosae thickness decreased (P<0.05). In addition, supplementation of red yeast improved villus height/crypt depth in duodenal (P<0.001). The red yeast supplementation at 4.0 g/kg increased villus height, villus width, crypt depth, and crypt area in jejunal compared with the other groups (P<0.001). However, supplementation of AGP increased muscularis mucosae thickness compared with the CON and RY (P<0.001). In ileal, laying hen fed RY0.5 decreased villus height and villus width (P<0.01) as well as laying hens fed RY0.5, 1.0, and 2.0 decreased crypt depth (P<0.05). Further, RY2.0 and RY4.0 improved villus height/crypt depth in ileal (P<0.001) while RY 1.0 decreased crypt area (P<0.001) fed laying hens. In addition, supplementation with red yeast decreased muscularis mucosae thickness (P<0.05). Villus and crypt cell proliferations in duodenal when red yeast supplementation at 1.0, 2.0, and 4.0 g/kg in laying hens diet (P<0.001). It can be concluded that red yeast supplementation at 2.0 and 4.0 g/kg of diet improved performance, egg quality, and small intestinal histology which can substitute AGP in layer hens.