Effects of dietary supplementation with phytase and formic acid on performance, intestinal histomorphology, cecal microbial populations, short-chain fatty acids content, nutrient digestibility, and tibia characteristics in growing quails

The present study was conducted to determine the effects of dietary supplementation with phytase and Na-formate on performance, intestinal histomorphology, cecal microbial populations, short-chain fatty acid composition, nutrient digestibility, and tibia characteristics in growing quails. The study used 360 one-day-old quail chicks and lasted 35 days. Five dietary treatments were formulated: a basal diet (positive control; PC), a diet containing 0.14 % available phosphorus (negative control; NC), the NC diet plus 500 FTU/kg phytase (NC + Phy), the PC diet plus 0.2 % sodium formate (PC + Formic), and the NC diet plus 500 FTU/kg phytase and 0.2 % sodium formate (NC + Phy + Formic). Chicks were randomly distributed into 30 subgroups (6 replicates per treatment) of 12 birds each. At week 5, birds in the NC group had significantly lower body weight than all other groups (P<0.05), and over the 0–5 week period, body weight gain in NC was significantly lower than in the other treatments (P<0.05). No significant differences in feed intake were observed among groups (P>0.05). By the end of the trial, feed conversion ratio in NC + Phy + Formic was significantly better than in PC, NC, and NC + Phy (P<0.05). Carcass yield was significantly reduced in NC compared with PC and NC + Phy + Formic (P<0.05), and mortality was significantly higher in NC than in the other groups (P<0.05). Villus surface area was significantly greater in NC + Phy, PC + Formic, and NC + Phy + Formic than in PC and NC (P<0.05). Cecal acetate and butyrate levels were significantly elevated in NC and NC + Phy + Formic (P<0.05), while propionate was higher in NC + Phy, PC + Formic, and NC + Phy + Formic (P<0.05). Branched-chain fatty acids (BCFA) and total short-chain fatty acid (SCFA) concentrations were significantly increased in the NC + Phy + Formic group compared with PC (P<0.05). Lactobacillus counts were highest in NC + Phy + Formic (P<0.05). Ileal digestibility of crude protein, dry matter, and phosphorus was significantly improved in NC + Phy and NC + Phy + Formic (P<0.05). Tibia weight, length, diameter, and breaking strength were not affected by the treatments (P>0.05). In conclusion, supplementing growing quail diets with phytase and sodium formate enhanced feed utilization and improved intestinal health, as evidenced by increased BCFA, total SCFA, and Lactobacillus populations.