Effects Of Combined Additives On The Quality Of Whole Corn Silage,Rumen Metabolism Characteristics And Molecular Structure Of Dairy Cattle

Whole plant corn silage has become one of the most important roughage dairy farming,the development and use of corn silage additives is greatly improve the nutritional value of corn silage to improve the quality of silage fermentation and improve the feeding effect,show the broad application prospect,composite additive mixing can make up the shortage of the single additive with defect,make the silage fermentation quality to achieve a better level,further improve silage characteristics,improve the utilization efficiency of silage.The main purpose of this paper is to use the orthogonal design method to screen and optimize the whole maize silage additive combination,in order to provide technical support and theoretical basis for the production of high-quality whole maize silage on cow production.The main contents of the study are as follows :（1）to evaluate the fermentation quality and nutritional quality of whole maize silage samples of different combinations by "wet chemistry".（2）the degradation characteristics of whole maize silage samples of different combinations in the rumen of cows were evaluated in vitro.（3）the protein and carbohydrate spectra of whole maize silage samples of different combinations were collected by atr-ft /IR technique and the molecular structure maps were analyzed to reveal the effects of different combinations of additives on the protein and carbohydrate molecular structure of whole maize silage samples.Experiment 1.Selection and optimization of different combinations of additives in whole maize silage and their effects on fermentation characteristics and nutrient quality.In this study,orthogonal design was used to screen and optimize the whole maize silage additive combination,and the fermentation quality and nutritional quality of the whole maize silage samples of different combinations were evaluated by wet chemistry method and CNCPS model.The results showed that silage treasure,calcium propionate and cumin essential oil all had effects on the fermentation quality of whole maize silage and had certain interaction.A2B1C2 was superior to other additive combinations.That is,（A）10 mg/kg+ propionic acid（B）200 mg/kg+ cumin essential oil（C）500 mg/kg is superior to other additive combinations.The nutritional value was evaluated by using the CNCPS system.The addition of different combinations of additives was the main factor that caused the difference of nutrients in whole maize silage.The A2B2C1 group was superior to other combinations in terms of true protein content,true protein utilization rate and starch content.Experiment 2,the effects of different combinations of additives on the degradation characteristics of whole maize silage in rumen of cows.Using in vitro method for different combinations of whole plant corn silage additives in dairy cows rumen degradation characteristics is analyzed,the results show that the whole plant corn silage making silage treasure,calcium propionate and add cumin essence of acetic acid,propionic acid,isobutyric acid and ammonium nitrogen have different degrees of influence,they after different combinations of propionic acid,isobutyric acid and ammonium nitrogen also has certain interaction,composite additive added after help to improve the rumen microbial fermentation and the concentration of NH3-N,thus change the nitrogen metabolism.Experiment 3.Effects of different combinations of additives on protein and carbohydrate molecular structure of whole maize silage.The ATR-FT/IR technique was used to study the molecular structure of proteins and carbohydrates in whole maize silage with different combinations of additives,and the correlation between the molecular structure map data and the nutritional components in test 1 was analyzed.The results show that the different additive combination between amides Ⅰ Ou De Feng high peak area,peak area,the amide II area,amide I region and amide II area peak area ratio and amide I region and amide II district of peak height ratio results show that the difference was significant（P < 0.01）;There was a significant positive correlation between PB3 and the peak height of the ming-helix（r=0.87,P=0.002）,and the peak height ratio of the ming-helix to the m1-fold（r=0.86,P=0.003）（P < 0.01）.The peak height and peak area of structural carbohydrate（STCHO）in whole corn silage under different additive combinations were significantly different（P < 0.01）.TCHO_1H,TCHO_1A,TCHO_3H,TCHO_3A,and the differences among the three subpeaks of total carbohydrate in whole corn silage were very significant（P < 0.01）.In this experiment,it was found that the peak area of CELC was negatively correlated with ADL（r=-0.65,P=0.059）.In other words,the larger the peak area of CELC was,the smaller the ADL was.The content of ADF in corn silage was negatively correlated with the peak area of STCHO and the peak area of CELC.Conclusion: based on the experimental results of this study,different combinations of additives have significant effects on the fermentation characteristics,nutritional components,molecular structure and biological degradation characteristics of whole maize silage.Using the combination of three different types of additives: silage treasure（lactobacillus）,calcium propionate and cumin essential oil can significantly improve the quality of whole maize silage.A2B2C1 and A2B1C2 are superior to other groups in terms of protein nutritional quality and fermentation quality,respectively.In terms of technical methods,the rumen degradation characteristics can be evaluated by artificial rumen technology.Some parameters of protein and carbohydrate molecular structure collected by atr-ftir technique can be used to reveal the difference of protein and carbohydrate molecular structure,and provide theoretical basis for nutrient quality assessment of feed.