| As a by-product of wine production,grape pomace contains a variety of biologically active substances,which has a certain feeding value,however,due to the relative lack of research on the functional application of grape pomace to livestock,its development and utilization rate is relatively low,therefore,this experiment was based on the purpose of developing grape pomace as a functional additive,broiler chickens were selected as the test object,and 180 healthy 30 day old Liangfeng broiler chickens with similar body weight were selected and randomly divided into 6 groups with 5 replicates in each group and 6 broiler chickens in each replicate.Respectively fed the basal diets containing 0%(group Ⅰ),0.5%(group Ⅱ),1%(group Ⅲ),2%(group Ⅳ),4%(group Ⅴ),8%(group Ⅵ)of grape pomace,and maintain the content of protein,metabolizable energy,methionine and lysine in each diet formula was basically equal.The formal trial period was 49 days.To study the effects of different dietary levels of grape pomace on their growth,nutrient metabolism,blood biochemistry,plasma anti-oxidation,and meat quality,and to explore its mechanism based on plasma metabolomics,so as to provide scientific basis for the rational use of grape pomace and the development of functional feed.The main results were as follows:(1)The results of production performance analysis showed that compared with the control group,adding grape pomace in the diet could significantly increase the average daily gain and significantly reduce the feed to gain ratio(P<0.01),among them,the highest ADG was in group Ⅳ,reaching 48.72 g/d,the lowest F/G was group Ⅴ,which was 2.70.The results of nutrient metabolism study showed that the protein metabolic rate of group Ⅴ was 59.79%,which was significantly higher than that of group Ⅰ(P<0.05),and there was no significant difference among other groups(P>0.05).(2)Serum biochemical analysis showed that the fasting blood glucose(GLU)concentration of groupⅠ was 13.38 mmol/L,and the fasting blood glucose concentrations of the other groups were significantly lower than that of group Ⅰ(P<0.01),but the difference between the groups was not significant(P>0.05).The results showed that the addition of grape pomace in the diet had a significant effect on the content of aspartate amino acid transferase(AST)and the concentration of serum uric acid(UA)in broiler chickens(P<0.01).The AST of group Ⅵ was the highest,reaching 264.7 U/L,and UA was the lowest,reaching 149.00 μmol/L.The study of plasma antioxidant indexes found that except group Ⅱ,the plasma levels of malondialdehyde(MAD)in the test groups were significantly lower than that in the control group,and group Ⅴ was the lowest,reaching 6.39 mmol/mL.The content of catalase(CAT)in test group Ⅴ reaching 38.69 U/mL,which was significantly higher than that in other groups(P<0.01).The content of glutathione peroxidase(GSH-Px)in test groups Ⅳ,Ⅴ and Ⅵ was significantly higher than that in test groups Ⅰ,Ⅱ,and Ⅲ(P<0.05),and the content in group Ⅵ was the highest,reaching 152.6 U/mL.Except for groupⅡ,the total antioxidant capacity(T-AOC)of the other experimental groups was significantly higher than that of the control group(P<0.05),and the content of group Ⅴ was the highest,reaching 22.80 U/mL.(3)The results of meat quality analysis showed that compared with the control group,the addition of grape pomace in the diet could significantly increase the content of initial moisture and crude protein in the breast muscle of the broiler chickens(P<0.01),and the content of initial moisture and crude protein of group V was the highest,reaching 73.57%and 24.66%respectively.In addition,the addition of grape pomace could also significantly increase the content of total amino acids(TAA),essential amino acids(EAA),and flavoring amino acids(FAA)in the breast muscles,among which group VI was the highest,reaching 23.21%,9.38%,and 7.09%,respectively.In group I,the content of inosinic acid was the lowest,namely 1750.37 mg/kg,which was significantly lower than that in groups V and VI(P<0.01).Compared with group I,the addition of grape pomace could significantly increase the relative content of linoleic acid and a-linolenic acid(P<0.01)in the breast muscles of broiler chickens in groups V and VI,and the highest content was in group VI,with the content of 32.51%,1.74%respectively.At the same time,compared with the control group,the content of saturated fatty acids(SFAs)in test groups IV,V，and VI decreased significantly(P<0.01),and the lowest was group VI,which was 30.36%.The content of monounsaturated fatty acids(PUFAs)in group I was 35.59%,which was significantly lower than that in test groups V and VI(P<0.01).(4)In order to study the possible reasons for the positive effects of grape pomace on the performance,nutrient digestion,antioxidant capacity and meat quality etc.of the broiler chickens,the experiment randomly selected 8 test chicken plasma samples each from group I and group V for extensive targeted metabonomics analysis in animals.The results showed that a total of 575 metabolites and 23 differential metabolites were detected from the broiler chickens’ plasma,of which 17 were up regulated and 6 were down regulated.KEGG metabolic pathway analysis results showed that the differential metabolites were mainly concentrated in 16 material metabolism pathways,among which there were 3 metabolic pathways with significant differences,in cholesterol metabolism and primary bile acid biosynthesis pathways,the addition of grape pomace reduces the expression of taurocholic and taurochenodeoxycholic acid in the broiler chickens’ plasma(P<0.05).The synthesis and degradation of ketone bodies promotes the expression of β-hydroxybutyric acid(P<0.05),showing that the addition of grape pomace had a positive effect on the body’s antioxidant capacity,anti-inflammatory,and neuroprotection.In conclusion,the addition of grape pomace in the diet can increase the daily gain of broiler chickens,reduce the feed to gain ratio,improve the production performance,and also have a positive effect on the crude protein metabolism rate of the broiler chickens;it can also improve the antioxidant capacity of the broiler chickens’ body,and it also has a certain positive effect on the meet quality of broiler chickens,and has great potential as a functional feed additive.In this experiment,the appropriate addition level of 4% is recommended. |
PDF Full Text Request