The study was conducted in the fields of Barakat Aba Al-Fadl Al-Abbas from the Al-Abbas's (p) Holy Shrine and the current work aimed to study the effect of substituting different levels of chemically treated crushed date seeds instead of barley in the concentrated diet of local male Awassi lambs to know its impact on productive and economic performance. Using a completely randomized design, forty-two male Awassi lambs (average body weights 22.6 ± 0.8 kg) at the age of 4-5 months were used, for the period from 10/8/2022 to 17/10/2022 (63 days). Animals were randomly distributed into seven groups (6 animals/group) in separate cages and experimental treatments were provided. All animals were fed concentrated diets at 3 % of body weight and barley straw was the main source of roughage and was provided as ad libitum. The normal crushed date seeds were replaced by 25.50 % instead of barley and the same proportions for the crushed date seeds were soaked with acetic acid and citric acid in seven treatments. There were significant differences observed in the averages of daily weight gain, feed intake and efficiency of feed conversion. Non-significant differences appeared in the rumen fluid parameters of pH and volatile fatty acids, while the treatments T6 and T7 recorded the lowest significant values in urea nitrogen compared to the highest values in the treatment T1 control. Treatments T6 and T7 were significantly superior in the digestion of nutrients over all treatments. All treatments achieved replacing crushed date seeds by 25 and 50 %, normal and soaked with organic acids, instead of barley, the best economic efficiency compared with the treatment T1 control.
