The effect of phytogenic additives on biochemical parameters of broiler chicken tissues.

The aim of this study was to evaluate the effect of combinations of bioactive compounds of plant origin (cinnamaldehyde, quercetin and 7-hydroxycoumarin) on productivity, meat quality and mineral metabolism in broiler chickens. During a 35-day experiment, 180 broiler chickens of the Arbor Acres cross were divided into 4 groups (n = 45): control (basal diet — BD) and three experimental treatments (BD with additives): I (cinnamaldehyde 30 mg/kg feed + quercetin 2.5 mg/kg feed), II (cinnamaldehyde 30 mg/kg feed + 7-hydroxycoumarin 0.3 mg/kg feed), III (combination of all three substances). Zootechnical parameters, chemical, amino acid and elemental composition of meat and liver from the experimental animals were assessed. Statistical significance was determined using the Mann-Whitney U-test (p ≤ 0.05). The greatest synergistic effect was demonstrated by the combination in the experimental group III. Compared to the control, in this group, the absolute live weight gain significantly increased by 880.7 g (by 51.4 %; p ≤ 0.05), and the average daily gain increased by 18.23 g (by 34.5 %; p ≤ 0.05). Feed conversion improved by 9.4 % (from 2.02 to 1.83 kg feed/kg weight gain), and the productivity efficiency index (EPEF) more than doubled by 257.04 points (from 209.37 to 466.41; p ≤ 0.05). The muscle tissue weight of carcasses in experimental group III was 246.5 g higher than the control value (31.9 %; p ≤ 0.05). A significant increase in the fat mass fraction was observed in the breast muscles of all experimental groups, e. g. in group I by 0.9 % (p ≤ 0.001). And in group II, an increase in the protein fraction by 2.2 % (p ≤ 0.05) was observed. The additives had a modulating effect on the mineral composition of tissues, causing, in particular, a decrease in the concentration of iron (Fe) in the breast muscles of groups I and III by 7.21 mg/kg (22.3 %; p ≤ 0.001) and 5.70 mg/kg (17.6 %; p ≤ 0.001), as well as an increase in the content of zinc (Zn) in the thigh muscles of groups I and II by 7.61 mg/kg (16.3 %; p ≤ 0.05) and 9.01 mg/kg (19.3 %; p ≤ 0.01), respectively. Thus, the combined use of cinnamaldehyde, quercetin and 7-hydroxycoumarin demonstrated a statistically significant positive effect on growth, feed efficiency and meat productivity of broilers, and also changed the biochemical profile of muscle tissue, which confirms the potential of this composition as an alternative to antibiotic growth promoters