“…Many other researchers reported a significant ( P < 0.05) improvement of FCR in broilers using diets supplemented with HRP alone up to 3 kg/ton ( Al-Kassie et al, 2011b ; El-Deek et al, 2012 ; Wadasen, 2012 ; Shahverdi et al, 2013 ; El-Amin et al, 2015 , Afolabi et al, 2017 ; Younis and Abdel-Latif, 2017 ; Soliman and Al-Afifi 2020 ) or mixed with black pepper ( El-Tazi, 2014 ; Moradi et al, 2016 ). However, Dougnon et al (2014) reported no difference in the FCR of broiler chicks on a diet supplemented with HRP at 0, 0.5, and 1% of the feed for 1 mo and 0.5 and 1% of the feed for 2 mo.…”