Effects of dietary oil- and water-soluble rosemary extracts on the growth performance, meat quality, and muscle antioxidant capacity in broiler chickens

Guo, Y.W., Chen, J.Y., Xie, K.Z., Zhang, T. Zhang, G.X. and Dai, G.J. 2023. Effects of dietary oil-and water-soluble rosemary extracts on the growth performance, meat quality, and muscle antioxidant capacity in broiler chickens. Animal Nutrition and Feed Technology, 23: 51–64.

This study evaluated the effects of dietary supplementation with commercial oil- and water-soluble rosemary extracts on the growth performance, meat quality and muscle antioxidant capacity of broiler chickens. A total of 560 one-day-old commercial broilers were randomly assigned into 7 dietary treatments. Each treatment contained 4 pens, each with 10 males and 10 females. The treatments were as follows: basal diet without rosemary extract (CON); CON + oil-soluble rosemary extract at 100, 150, and 200 mg kg⁻¹ (0–100, 0–150, and 0–200); and CON + water-soluble rosemary extract at 100, 150, and 200 mg kg⁻¹ (W-100, W-150, and W-200). At d 112, 4 males and 4 females from each pen were randomly selected and slaughtered to investigate the effects of rosemary extract on the performance to be evaluated. Compared with the CON, the feed conversion ratios of other treatments were lower (P<0.05) apart from the basal diet supplemented with water-soluble rosemary extract at 200 mg kg⁻¹. The levels of moisture loss in breast and thigh muscle of the CON and the treatments supplemented with oil-soluble rosemary extract were lower than that of the treatments supplemented with water-soluble rosemary extract. The total antioxidant capacity (T-AOC) values in treatments supplemented with oil-soluble rosemary extract was greater than the other treatments, yet the malondialdehyde (MDA) values showed the opposite trend. Overall, dietary supplementation with oil-soluble rosemary extract can reduce feed conversion ratio, improve meat quality and increase muscle antioxidant capacity.