Lemongrass supplementation to Farafra ewes improved feed utilization, lactational performance and milk nutritive value in the subtropics.

Application of phytogenic feed additives in livestock production is a sustainable practice and the search for more phytogenic options continues. This study was conducted to investigate the impact of lemongrass supplementation on nutrient utilization, rumen fermentation and milk production and composition. Thirty gestating Farafra ewes were randomly assigned to three experimental treatments of control (without a supplement), or with the supplementation of 5 g (LEM5 treatment), or 10 g of lemongrass/ewe/d (LEM10 treatment) for 12 weeks. Lemongrass supplementation at both doses did not influence (  > 0.05) nutrient intake, but improved nutrient digestibility ( < 0.05). Furthermore, LEM5 and LEM10 treatments improved ( ≤ 0.001) ruminal total volatile fatty acids, acetate and propionate. Blood glucose was increased ( < 0.05) and cholesterol was decreased in ewes supplemented with lemongrass at both doses. Milk yield, energy corrected milk yield, and milk component were improved ( ≤ 0.001) in ewes supplemented with lemongrass at 5 and 10 g while the feed efficiency was decreased. Lemongrass supplementation at both doses increased ( = 0.040) the proportion of milk total conjugated linoleic acid without affecting other milk fatty acids. In most of the parameters evaluated, there was no significant difference between LEM5 and LEM10. Therefore, lemongrass supplementation at 5 g/ewe/d can be used in dairy production with positive impacts.