Study Of Fresh Mare’s Milk Nutritional Quality Of Grazing Yili Horse

This paper based on fresh mare’s milk on Yili horse of pasture, studied on different parity,lactation period and milking time point influence on milk yield and milk composition. Used fat,protein, lactose, total solids and somatic as evaluation factors to establish fresh mare’s milk qualitygrading and evaluation model with cluster analysis, principal component analysis, discriminantanalysis. The main research results are as follows:Studied the difference of day milk yield and nutrents of fresh mare’s milk on Yili horse ofpasture on different parity, showed that in parity4, the milk’s nutrents are higher(1.35%milk fat,milk protein1.82%, lactose6.13%and1.82%of the total solids). in parity7, the milk’s nutrentsare fewer(1.3%milk fat, milk protein1.66%, lactose5.86%and1.66%of the total solids), butmilk yidel is higher(12.49L).analyzed the correlation between the indexes and established the regression model on dailymilk yield and milk protein, total solids and lactose, milk fat, milk protein, Yday milk yield=840.157－106.073Xmilk protein, Ytotal solids=－0.147+1.187Xlactose cream+0.864milk fat+0.803Xdairy protein. Accordingto this can guide raw materials fresh mare’s milk select for rational, and provide a scientific basisfor determining quality mare’s milk production.Used six times polynomial regression model to get the fitted curve of milk yield and nutrientcomposition changes on Yili horses of pasture after childbirth30~100days.The determinationcoefficient R2were greater than0.86, show that six times polynomial regression model can wellreflect the the change rule of milk yield, milk fat, milk protein, lactose, total solids on Yili horsesof pasture after childbirth30~100days.Based on the research of the fitted curve, milk protein infresh mare’s milk, lactose, total solids content is higher after childbirth35days,65days,65days.At the same time, milk fat content is fewer; The milk fat content is higher in fresh mare’s milkafter childbirth30days,50days,85days.Comprehensiving the change rule of milk composition on whole day, at10:00in the morning,milk fat, lactose, lower total solids content were lower respectively1.19%,6.04%,9.56%,6.04%,milk protein and somatic cell count was higher respectively1.83%,32.7%of fresh mare’s milk;At16:00in the afternoon, milk fat, lactose, total solids content in milk were higher respectively1.36%,6.14%and9.67%, fresh horse, but the content of milk proteins and cells are lowerrespectively1.69%,25.34（1000/mL）. Above the all, products quality is lower at10:00in themorning, and milk quality is higher at16:00in the afternoon.The relation between whole day sample and12:00and14:00two time points is the highestdegree, the regression equations between milk fat, milk protein, lactose, total solids, and somaticcell on whole day sample and12:00and14:00two time points fitting are:Y=0.441X22+0.396X3+0.182（R=0.871，P<0.001）、Y=0.473X2+0.422X3+0.191（R2=0.904，P<0.001）、 Y=0.472X2+0.412X3+0.716（R2=0.871， P<0.001）、 Y=0.475X2+0.408X3+1.111（R2=0.863，P<0.001）、Y=0.853X2+0.808X3-15.073（R2=0.903，P<0.001）。Therefore, accordingto12:00and14:00milk composition measurements predict milk composition content on wholeday.Using stepwise cluster analysis, factor analysis, discriminant analysis and other methods to study milk quality evaluation and classification on the Yili Zhao su fresh mare’s milk, the resultsshowed that the fresh mare’s milk can be divided into excellent, good, medium and bad level;Class4, scored3.448, is classified as excellent level; Class2, scored2.662, the quality is good, isclassified as good level;Class1, scored2.57, poor quality, is classified as medium level;Class3,scored1.3, the quality is the worst, is classified to the poor level. Using the method of stepwisediscriminant analysis to get the mathematical model of fresh mare’s milk quality grading, theaccuracy is94.6%through the model predicts, show that the discriminant function can rationaljudgement of unknown samples.