Performance assessment of broiler chickens given mushroom extract alone or in combination with probiotics.

A study was conducted to evaluate the effect of combined Shiitake mushroom (Lentinus edodes) extract with probiotics (PrimaLac) on the growth and health of broiler chickens. In trial 1, 540 d-of-hatch chicks were randomly assigned to 6 treatment groups, replicated 3 times, with 15 males and 15 females per pen for 3 wk. Dietary probiotics and mushroom treatments were as follows: 1) control feed + ad libitum tap water; 2) control feed + skip-a-day mushroom water; 3) control feed + ad libitum mushroom water; 4) probiotic feed + ad libitum tap water; 5) probiotic feed + skip-a-day mushroom water; 6) probiotic feed + ad libitum mushroom water. Body weight gain, feed consumption and efficiency, mortality, bursa, liver, and spleen relative weights of chicks were taken. In trial 2, the performance of broilers 3 to 7 wk withdrawn from the mushroom extract was evaluated along with the comparative level of fecal biofidobacteria in the control and mushroom extract treatment (trt). Mortality, weight gain, feed consumption and efficiency, carcass yield, fat pads, bursa weights and fecal bifidobacteria were measured in trial 2. In trial 1, significant differences (P < 0.05) in female weight gain (trt 4-0.62 vs. trt 1-0.54 kg) and male spleen weights were observed. In trial 2, significant differences were observed in male weight gain (trt 2-2.40 vs. trt 4-1.12 kg), male and female fat pads, male bursa weights (trt 3-0.15 vs. trt 6-0.39), female carcass yield percentage (trt 1-77.8 vs. trt 4-66.4), and feed consumption and efficiency. Body weights were severely depressed in the male broilers receiving the probiotics feed in treatments 4, 5, and 6, but not in the female broilers. These results indicate that performance differences in gender occur with additives during different grow-out periods, and mushroom extract promotes bifidobacteria growth in broiler chickens after 4 wk of withdrawal. It appears that probiotics and mushroom extract offered no combination potential for weight gain, which was compromised in this study, but possible health-enhanced attributes.