Effect of dietary tannins on the performance, lymphoid organ weight, and amino acid ileal digestibility of broiler chickens: A meta-analysis

Abstract

Background and Aim: Tannins are functional secondary metabolites that may provide benefits to ruminants. However, to date, their effects on broiler chickens remain inconclusive. This study aimed to evaluate the effectiveness of dietary tannin levels on the performance, body organs, and amino acid (AA) digestibility of broiler chickens using a meta-analysis. Materials and Methods: After verification and evaluation, a total of 22 articles were included in the present study. All data regarding dietary tannin dosages, performance, digestibility, and gastrointestinal physiology of broiler chickens were tabulated into a database. The database data were then statistically analyzed using mixed models, with tannin dose as a fixed effect and study as a random effect. Results: High levels of dietary tannins negatively affected the average daily gain and average daily feed intake of broiler chickens according to linear patterns (p<0.001). In addition, dietary tannins decreased drumstick and liver weights, as well as bursa of Fabricius and spleen weight (p<0.05). Meanwhile, other carcass traits (i.e., thigh, wings, and body fat) were not influenced by dietary tannins. Regarding AA digestibility, high dietary tannin concentrations induced negative responses on isoleucine, leucine, and methionine digestibility (p<0.05). Conclusion: Dietary tannins appear to have a negative effect on broiler performance, lymphoid organ weight, and AA ileal digestibility. Hence, the addition of tannins to broiler diets is not recommended.

Effects of the Inclusion of Star Gooseberry (Sauropus androgynus) Leaf Meal in Ration on Physical and Nutritional Quality of KUB Chicken Breast Meat

“…The inclusion of SGLM by up to 3% only seemed to give no significant increase in ration protein contents. Contrary to the findings by (Woyengo & Nyachoti, 2010) and (Hidayat et al, 2021) active compounds including tannin contained in SGLM in this study might not affect amino acid digestibility. These have led to similar protein intake and meat protein synthesis.…”

Dietary Phytogenic Extracts Favorably Influence Productivity, Egg Quality, Blood Constituents, Antioxidant and Immunological Parameters of Laying Hens: A Meta-Analysis

“…High levels of tannins (more than 10 g/kg feed) from plant extracts in the poultry diet can precipitate the protein and reduce fat digestion by binding bile salts or inactivating digestive enzymes [ 4 , 9 , 10 ]. Although several qualitative review articles have discussed differences in the responses of laying hens to dietary phytogenic extracts and a meta-analysis approach in broiler chickens [ 11 , 12 ], no meta-analysis has been performed to date in laying hens to quantify these differences. Therefore, the current meta-analysis study aimed to assess the impact of dietary phytogenic extracts on laying productivity, egg quality, blood constituents, and antioxidant and immunological parameters.…”

Pumpkin seeds, lemongrass essential oil and ripleaf leaves as feed additives for Ascaridia galli infected laying hens

“…In contrast, no impact of ripleaf or other tanniferous plants on the feed conversion rate was reported in other studies (Hidayat et al 2021;Temur and Uslu 2019).…”