Application Of CNCPS To Ration Evaluation And Performance Prediction In Dairy Cattle

This thesis based on the principles and methods of Cornell Net Carbohydrate and ProteinSystem (CNCPS), made the survey of cows raising situation under different cultivation modes of tothe three areas, and used classification method of CNCPS to determine the nutritional values of thelocal main feed. And, evaluated the rations and feeding under three cultivation modes by CNCPSmodel. And based on the result of feeding experiment of dairy cattle on household farm, evaluationof application effect to production and performance prediction effect of CNCPS were carried on.Trial 1 Apply CNCPS to investigate dairy cattle feeding and management situation in three areasIn order to probe variance under cultivation modes of cows in three areas and lay thefoundation for the evaluation for the future, the author surveyed their feeding and managementsituation of three areas which including cow households of Wujia town in Shuangcheng city inHeilongjiang province, Hailin farm of Hailin city and modernized diary farm in Zhangwu county inLiaoning province in the second half of 2006. The survey went on through the questionnaire andpractical observation. The survey showed, total number of milk cows in cow households surveyedwere 141, and roiling herd average (RHA) milk yield were 3300 kilograms averagely. Milk cowquantities of Hailin farm were 1050, and RHA milk yield were 6500 kilograms. Milk cowquantities of modernized diary farm in Zhangwu county were 1100, and RHA milk yield were 7000kilograms. Modernized diary farm in Zhangwu adopted total mixed ration (TMR), and Hailin farmadopted quasi-TMR. Forages of modernized diary farm in Zhangwu county were corn silage,Chinese wildrye and alfalfa. In Hailin farm, main forages were corn silage and Chinese wildrye,and there was alfalfa once in a while. All cow households fed corn stover as main forages. Thesurvey results indicated that intensive cultivation mode could be better to develop performance ofdairy cattle.Trial 2 Determination of nutritional ingredients of common feeds for cows, according to theCNCPS scheme for feed carbohydrate and protein fractionationThis trial analyzed and determined nutritional ingredients of major feeds in three areas,according to the CNCPS classification for feed carbohydrate and protein fractionation, whichestablished the foundation of the data for the later trial. The determination results indicated theanalytical methods of CNCPS determine more indexes, and can reflect the nutrient component of the feed. It reflected animal's utilization situation to the feed at the same time and made theevaluation of the nutritional value of feeds more accurate.Trial 3 Apply CNCPS to evaluate the current rations in three areasAim of this trial is to evaluate rations and find deficiency, as to improve. Through inputtingthe investigation results of the cow households and dairy farm and nutritional ingredients of rationsinto CNCPS software, outputted to the evaluation results on the current rations by CNCPS software.The results revealed, CP content in ration of cow households is lower than two dairy farms, andrations of Hailin farm and Zhangwu modernized diary farm could meet the demand of microbe inruman for nitrogen and peptide, but the supply of the nitrogen in ration went beyond 130% ofrequirement on Zhangwu modernized diary farm. It was apt to cause ruminal metabolism diseasesfor high-production cows.Trial 4 Application of CNCPS in rations combination and feeding effect testAim of this trial is to examine application and prediction effect of CNCPS model in ourcountry. The trial carried on on the original foundation of feeding way and feeds and adopted 2×2inverse trial design, and setted up two treatment which were ration adjustment (Ⅰ) and control (Ⅱ).10 middle lactation cows were chosen which divided into two groups at random. And each groupconsisted of 5 cows. According to CNCPS model evaluation of the ration formulation and result ofperformance prediction, to carry on cows feeding experiment. The results indicated that milk yieldof group of applied CNCPS model to adjust ration (groupⅠ) was average higher 2.85kg thancontrol group (groupⅡ), two kinds of treatment differences were extremely prominent (P＜0.01).Meanwhile, the prediction accuracy range of CNCPS for DMI of each experimental group indifferent periods was from 101% to 105%, and difference of actual DMI and predicted DMI is notprominent (P＞0.05). And the prediction accuracy range of CNCPS for milk yield of eachexperimental group in different periods was from 98.62% to 104.04%, and difference of predictedmilk yield and actual milk yield are not prominent (P＞0.05). Therefore, CNCPS system would beable to effectively regulate the balance of supply and demand of the nutriment and find out mainnutrition factor to influence milk yield. And CNCPS could be regarded as an effective tool tocompound rations scientifically and evaluate feeding program. Meanwhile, it is also a powerful toolfor production prediction.