Effects of kudzu leaf meal on growth performance and the biochemical, antioxidant, and immune indexes for serum from broilers

A total of 384 21-day-old broilers with moderate body weights were randomly divided into four groups with six replicates per group and 16 birds per replicate. The broilers were fed a basal diet supplemented with 0 (control group), 1%, 2%, or 3% kudzu leaf meal. The experiment lasted 49 days. This study aimed to investigate the effects of kudzu leaf meal on growth performance, serum biochemical indexes, and the antioxidant and immune function of broilers. The results showed 1) The kudzu leaf meal had no significant effect on average daily gain, average daily feed intake, and the feed to gain ratio of broilers (P > 0.05); 2) Diets supplemented with 2% and 3% kudzu leaf meal significantly increased serum albumin and low density lipoprotein content, and showed reduced triglyceride content and glutamic transaminase activity (P < 0.05); the diet supplemented with 3% kudzu leaf meal significantly increased serum total protein and reduced the urea nitrogen, total cholesterol, high-density lipoprotein, and glutamine transaminase contents (P < 0.05); 3) Compared to the control group, the serum total antioxidant capacity and glutathione peroxidase activity of broilers in the kudzu leaf meal addition groups significantly increased and the malondialdehyde content of broilers in the 3% kudzu leaf meal group significantly decreased (P < 0.05). 4) Compared to the control group, the serum immunoglobulin M content of broilers in the 1% kudzu leaf meal group significantly increased, and the serum immunoglobulin M and Interleukin -1β contents significantly increased in the 2% kudzu leaf meal group. The serum immunoglobulin G and immunoglobulin M contents significantly increased, whereas the Interleukin -1β and Interleukin -2 contents decreased in the 3% kudzu leaf meal group (P < 0.05). In conclusion, diets supplemented with 1% to 3% kudzu leaf meal had no negative effects on growth performance, and increased the antioxidant and immune function and health of broilers to a certain extent. Kudzu leaf meal can be used in the diet of broilers and the addition of 3% kudzu leaf meal was the optimal dose.