Analysis of Somatic Cell Counts in Raw Milk of Individual Dairy Cow from Dairy Farm in China

The objectives of this study were to analyze total average value,distribution frequency and mainly impact factors ofsomatic cell counts(SCC)in raw milk from individual dairy cow.The total data were from 33 dairy farms in China,23 351 Chinese Holstein cows,covering with 16 provinces,225 775 raw milk SCC from 2007 to 2009,and analysed by GLM model of SAS9.0.The results showed that: the total average of SCC in raw milk from individual dairy cow was 48(104cell/mL) with the standard deviation of 117(104cell/mL);Under the different cell count grades,the distribution frequency and influence coefficient of SCC,which were defined as the influence of individual dairy cow on total group of dairy cows,respectively were about 77.9% and 0.26,at SCC≤50(104cell/mL)grade no mastitis;at subclinical mastitis 50SCC≤100(104cell/mL) grade,about 11.3% and 0.16;and at clinical mastitis SCC100(104cell/ml)grade,about 10.8% and 0.58.It was a normal distribution of the Somatic Cells Score(SCS).There was significant difference(P0.01)of SCS between the factors that were from individual dairy cow(dairy parity,milk yields,milk fat,milk protein,stage of lactation) and from environmental(lactation month,lactation season),and no significant differences(P0.05) of SCS between farming region and different dairy farm.In a word,the total average value and distribution frequency of SCC in individual raw milk from dairy farms were not exceed 50×104 cell/mL;with these data,we could control and keep the balance with the SCC in raw milk in practice.