Rumen bacteria, carcass traits, and meat quality of growing goat fed diets with different levels of Azolla Pinnata.

Low availability and high prices of concentrate feeds drive the use of sustainable animal feeds, such as Azolla. Azolla is rich in nutrients and bioactive compounds that improve rumen microbial fermentation and animal performance. This study investigated the effect of replacing concentrate feed mixture (CFM) with Azolla pinnata on the rumen bacteria and fermentation, growth performance, and meat quality of growing Damascus (Shami) goats. Twenty-seven growing male goats were used for 153 days to receive three treatments (n = 9): a control group received a non-supplemented diet composed of Berseem hay and CFM (CC); a group received the control diet with 10% Azolla from the CFM (AZ10); and a group received the control diet with 20% Azolla from the CFM (AZ20). Replacing CFM with Azolla increased the diversity of the rumen bacteria, with the enrichment of phyla Bacteroidota and Firmicutes. Azolla enhanced the prevalence of fibrolytic bacteria, Ruminococcus, Butyrivibrio, and Christensenellaceae R-7 group. Total volatile fatty acids (VFA) increased in AZ10 by 39% and 25% compared to groups CC and AZ20, respectively. Growth rate was higher in AZ10 by 35% and 18% compared to CC and AZ20, respectively. Azolla supplementation reduced the fat content of meat and reduced saturated fatty acids of meat by 52% in AZ10 and 21.5% in AZ20 compared to group CC, while it improved the antioxidant capacity and unsaturated fatty acids in meat. Azolla can substitute the conventional feed mixture of growing goats at 10%.