A Ph.D. thesis at the College of Agriculture at the University of Kirkuk discussed the addition of L-carnitine and herbal methionine and their mixture in the metabolism of sunflower oil added to the diet and its effect on the productive and physiological performance of broiler chickens. Salma Bahjat Karim's thesis sought to ascertain the effect of adding L-carnitine and herbal methionine, as well as their combination, on the productive and physiological performance of broiler chickens following the use of 320 one-day-old Rose 308 unsexed broiler chicks in the first experiment. In the second experiment, 250 chicks of the same species were used. The thesis concluded that adding a mixture of L-carnitine and herbal methionine significantly improved the studied traits.