TDK conference 2016

Nutritional factors proved to be potent modulators of metabolism of chickens, enhancing promotion and maintenance of metabolic health, thus welfare and economic growth of animals. Further, they are able to influence meat quality as well, which is of outstanding importance for both poultry industry and human health and nutrition.

The present work was designed to investigate the effect of two different cereals (maize or wheat), highly different in their soluble non-starch polysaccharide content, with dietary crude protein level matching standard requirements of the dietary phase or reduced by 15% (normal protein [NP] and low protein [LP] groups, latter supplemented with limiting amino acids), on the metabolism of broilers. Further, diets were fed with or without application of sodium (n-)butyrate by the commonly used dose in poultry nutrition (1.5 g/kg diet). We also aimed to assess age-dependent responsiveness of animals to the treatments. Therefore, blood samples of Ross-308 male broilers were collected on day 7, 21 and 42 (week 1, 3 and 6 samplings). Plasma concentrations or activities of selected metabolic parameters were determined to monitor biochemical and hormonal changes provoked by examined nutritional factors. Effects of wheat-based diet compared to maize-based dietary groups, and differences between NP and LP as well as between control and butyrate-supplemented groups were studied by multi-way ANOVA and were considered as main effects.

Plasma total protein (TP) concentration was increased in groups receiving wheat-based diet or containing NP on week 3, while butyrate supplementation reduced albumin/TP ratio on week 1. Plasma uric acid level was elevated by wheat-based diet on week 1 and 3; by NP on week 3 and 6 and by butyrate supplementation on week 3. Aspartate aminotransferase activity increased as the effect of wheat-based diet on week 3, and that of creatine kinase was diminished by NP on week 3 and 6. Blood glucose level decreased in groups reared on wheat-based diet on week 3, and parallely, triglyceride concentration was found higher in the same groups on week 3.

Concluding our results, investigated nutritional factors were found to affect certain biochemical parameters of broilers on an age-dependent manner, underlining the importance of attentive diet formulation, especially in the grower phase. Type of cereal proved to be an effective modulator of primarily the protein and amino acid metabolism. Further, reduced dietary crude protein content, supplemented with limiting amino acids has shown to have beneficial impact on growth and health of chickens, which has great importance from economical and environmental point of view.