Effects Of Short-chain Ketonic Acid On Growth Performance And Blood Indexes In AA Broilers

Short-chain ketonic acid is intermediate metabolites which regulated the organism’s metabolism. It is a new feed additive, which had characteristics of safety and non-residue. Short-chain ketonic acid had significant impact on growth performance in animal, the content of short-chain ketonic acid in the feed varied depending on animal species and animal growth stage. Based on preliminary studies, the study was to evaluate the effects of short-chain ketonic acid on growth performance and blood indexes in AA broilers, and to determine optimum level of short-chain ketonic acid in broilers diet. These results would provide theoretical basis and application parameters for short-chain ketonic acid as feed additive applying to the animal production.One hundred and ninety-two healthy broilers were randomly allocated into 4 groups with 4 replicates per group and 12 broilers per replicate. Broilers had similar initial weight. The control group was fed with basal diet, and the other three experimental groups were fed with basal diet supplemented with 0.375%, 0.500% and 0.625% short-chain ketonic acid, respectively. The experiment lasted for forty-two days. For each replicate, broilers weight and surplus feed were record to calculate broilers average daily gain, broilers average daily feed intake and broilers feed conversion ratio at the beginning of every two week. At the experiment of 29 d, selected one broiler, its weight was close to broilers average weight of each replicate, and collected blood through jugular artery puncture, then killed to take out and weigh the spleen, bursa and thymus. The results indicated:1. Effects of short-chain ketonic acid on growth performance of AA broilers. At the experiment of 14 d, 28 d and 42 d, broilers weight of experimental groups were higher than the control group, 28 d broilers weight of groupⅠ and Ⅱ were significantly higher than the control group(P<0.05). Compared with the control group, broilers weight of groupⅡrespectively increased by 2.46%(P>0.05), 3.32%(P<0.05) and 6.72% at the same age(P>0.05). In the experiment of 1-14 d, the broilers average daily feed intake in experimental groups were a little more than the control group(P>0.05). The broilers average daily gain of group Ⅱ was significantly higher than the control group(P<0.05). In the experiment of 1-28 d, the broilers average daily gain of groupⅠand Ⅱ were significantly higher than the control group(P<0.05), the broilers average daily gain between the control group and group Ⅲ had no significant difference(P>0.05), the broilers average daily feed intake of groups had no significant difference(P>0.05). In experiment of 1-42 d, compared with the control group, the broilers average daily feed intake of experimental groups increased(P>0.05). The broilers average daily gain of group Ⅰ, Ⅱ and Ⅲ respectively increased by 1.85%(P>0.05), 6.84%(P<0.05) and 4.74%(P>0.05). In experiment of 1-14 d, 14-28 d and 28-42 d, the broilers average daily gain of group Ⅱ were higher than the control group by 2.86%(P>0.05), 3.74%(P<0.05) and 10.58%(P>0.05), and the improved range of the broilers average daily gain were greater than groupⅠand Ⅲ. With the increase of age, the improved range was greater. Short-chain ketonic acid had no significant difference on the broilers feed conversion ratio(P>0.05).2. Effects of short-chain ketonic acid on biochemical indexes in serum. The content of broilers total protein and globulin increased with short-chain ketonic acid(P>0.05), the ratio of albumin and globulin of group Ⅲ significantly reduced(P<0.05). Short-chain ketonic acid increased the content of broilers high-density lipoprotein and reduced the content of broilers triglycerides. The varied range of group Ⅱ was the supreme on the content of broilers triglycerides and high-density lipoprotein(P>0.05). The content of broilers albumin, total cholesterol and low-density lipoprotein of groups had no significant difference(P>0.05).3. Effects of short-chain ketonic acid on immune indexes of AA broilers. Short-chain ketonic acid had no significant effect on broilers immune organ indexes(P>0.05). Compared with the control group, the content of broilers immunoglobulin and complement in the experimental groups increased(P>0.05). The content of broilers C3 in the group Ⅲ was significantly higher than the control group. The improved range of group Ⅱ on the content of broilers Ig A, Ig M and C4 were higher than groupⅠand Ⅲ(P>0.05).4. Effects of short-chain ketonic acid on antioxidant indexes of AA broilers. Short-chain ketonic acid increased the content of T-AOC and reduced the content of MDA in serum and liver(P>0.05). Compared with the control group, the activity of GSH-PX in serum of group Ⅰ, Ⅱ and Ⅲ respectively increased by 13.95%(P>0.05), 30.04%(P<0.05) and 31.56%(P<0.05). With the increased supplementation of short-chain ketonic acid, the activity of T-SOD in liver of the experimental groups increased(P>0.05).In summary,short-chain ketonic acid increased broilers feed conversion rate, regulated broilers organism’s metabolism, improved broilers immune function and enhanced broilers oxidation resistance. The optimum supplementation of short-chain ketonic acid in the diet of AA broilers was 0.500% in present study.