Dietary supplementation with citrus extract alters the plasma parameters, circulating amino acid profiles and gene expression of small intestinal nutrient transporters in Chinese yellow-feathered broilers

Feeding citrus pomace fermented with combined probiotics improves growth performance, meat quality, fatty acid profile, and antioxidant capacity in yellow-feathered broilers

Introduction

The reasonable and efficient utilization of agricultural by-products as animal feed has the capacity to not only mitigate the scarcity of conventional feedstuff but also alleviate the environmental load. This study was aimed to investigate the effects of feeding citrus pomace (CP) fermented with combined probiotics on growth performance, carcass traits, meat quality and antioxidant capacity in yellow-feathered broilers.

Methods

A cohort of 540 female yellow-feathered broilers (Qingyuan partridge chicken, 90-day-old) were randomly divided into three groups and, respectively, fed the basal diet (Control), diet containing 10% unfermented CP (UFCP) and diet containing 10% fermented CP (FCP).

Results

The results showed that dietary FCP significantly increased (p < 0.05) the final-body-weight and average-daily-gain of broilers, and the pH45 min and b*24 h values in breast muscle, while tendentiously lowering the feed-to-gain ratio (p = 0.076). The levels of inosine monophosphate (p < 0.05) and intramuscular fat (p = 0.083) in the FCP group were higher than those in the control group. Remarkably, dietary FCP and UFCP increased the levels of polyunsaturated fatty acids (PUFAs) and n-6 PUFAs (p < 0.05). Moreover, dietary FCP decreased (p < 0.05) the malondialdehyde content and increased (p < 0.05) the glutathione peroxidase content in serum. Ingestion of FCP and UFCP increased the levels of total antioxidant capacity and catalase activity in serum, and concentrations of glutathione peroxidase and catalase in breast muscle (p < 0.05). Additionally, diet containing FCP or UFCP upregulated the expression of SREBP - 1c, FAS, NRF2, GSH-Px, and CAT in breast muscle (p < 0.05).

Discussion

Overall, dietary supplementation with FCP obviously improved meat quality, enhanced the antioxidant capacity and regulated the lipid metabolism, contributing to the improvement of growth performance of yellow-feathered broilers.

Early addition of enzyme-treated soybean in the diet improves amino acid absorption and protein digestibility by promoting digestive enzyme activity in broilers

Early nutritional regulation has become a research hotspot. The present study was undertaken to assess dietary early addition enzyme-treated soybean meal (ESBM) on nutrient digestibility, amino acid absorption, and intestinal development of broilers. Four hundred and fifty 1-day-old broilers were divided into three groups with 10 replicates of 15 broilers and fed with a basic diet, 2.5 or 5% ESBM during 1-10 days. Then, all groups were fed the same basic diets until 42 d. The obtained results indicated that supplementation of ESBM in early stage resulted in heavier BW and a better feed conversion ratio during the experimental periods compared with the control group. Supplementing the broiler's diet with 5% ESBM led to enhance digestibility of DM, CP and decrease abdominal fat yield (P < 0.05). Meanwhile, 5% ESBM in the early diet increased villus height (P < 0.05, d 21) and reduced the crypt depth in jejunum and ileum (P < 0.05, d 42). Dietary 5% ESBM supplementation improved enzyme activity and upregulated nutrient transporters expression in jejunum, increased plasma amino acid (AA) concentrations (P < 0.05, d 10). In conclusion, our data demonstrated that supplementation ESBM promote intestinal development, upregulate AAs and peptide transporters gene expression for physiological absorption of AAs, and improve protein digestibility caused by intestinal enzyme activity, thereby improving growth performance.

A comprehensive review on natural phenolic compounds as alternatives to in-feed antibiotics

Intensive livestock and poultry farming in China largely relied on the use of in-feed antibiotics until July 2020. The consequences of antibiotic overuse in animal feed include accumulation in animal products and the development of bacterial antibiotic resistance, both of which threaten food safety and human health. China has now completely banned the circulation of commercial feed containing growth-promoting drug additives (except Chinese herbal medicine). Therefore, alternatives to in-feed antibiotics in animal production are greatly needed. Natural phenolic compounds (NPCs) exist widely in plants and are non-toxic, non-polluting, highly reproducible, and leave little residue. Many natural flavonoids, phenolic acids, lignans, and stilbenes have polyphenol chemical structures and exhibit great potential as alternatives to antibiotics. In this review we delineate the characteristics of plant-derived NPCs and summarize their current applications as alternatives to in-feed antibiotics, aiming to provide new strategies for antibiotic-free feeding and promote the development of more sustainable animal husbandry practices.