Tannins are a diverse group of plant phenolic compounds. Condensed tannins (CTs) represent a major subgroup of tannins and were extracted from tilia (Tilia L.) flowers and black locust (Robinia pseudoacacia) leaves. These extracts were examined for their effects on the metabolic profile of chicken caeca. By using in vitro, a nuclear magnetic resonance (1H-NMR), which was combined with multivariate statistics, the current study was applied for the first time to investigate how three different CT compositions, procyanidins (PC) and/or prodelphinidins (PD) units influenced the metabolic end-products in caecal contents of chickens. In the presence of tannins, glutamate, leucine, lysine, pyroglutamate, phenylalanine, proline, and sarcosine were significantly decreased. CT extracts significantly influenced the fermentation, increasing the concentrations of some fatty acids such as acetate, butyrate, and propionate whereas. In contrast, lactate decreased between the treatments. This study identified the key structural features of CTs that contain either high molar proportions of PD or PC, which might be useful to improve the efficiency of feed utilization in chickens.

Objective: The purpose of this work was to investigate the combination of early-age acclimation and linseed dietary inclusion in enriching polyunsaturated fatty acids (PUFAs) in broilers meat as a strategy to mitigate heat stress. Materials and Methods: A total of 400 broiler chicks were assigned to four experimental groups with four duplicates (25 animals each): C: control (basal diet), AC: early-age acclimated (basal diet), Cl: fed 5% ground linseed, and Acl: early-age acclimated and fed 5% ground linseed. The lipid and fatty acid contents of different parts (breast, thigh, liver, subcutaneous, and abdominal fat) of broilers were determined. Results: Low levels of lipids and unsaturated fatty acids have been found in the meat of accli¬mated broilers. Higher levels of linolenic acids were noted in Cl thigh meat compared to C (6% vs. 2.68%, respectively). The results showed that oleic and linoleic acids constitute a large part of the PUFAs of different meats. The most elevated levels of monounsaturated fatty acids were recorded in the breast meat of AcL animals. The highest content of omega-3 was recorded in the liver of AcL animals compared to that of C (14.98% vs. 7.8%, respectively). Conclusion: We suggest that the combination of treatments during hot conditions has led to the reversion of the environment-affected variables to accepted values, and yields better ther¬moresistance, PUFA-enriched meat, and safeguard animal health which conferred to birds better solutions to reduce fatigue and hypoxic activities, which induces a considerable consumption of oxygen. [J Adv Vet Anim Res 2021; 8(2.000): 237-245]