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Although the newborn animal fat provide a lot of energy and essential fatty acids, but high concentrations of C14: 0 (myristic acid) and C16: 0 (palmitic acid) to promote plasma LDL cholesterol concentration increased, thereby inducing cardiovascular and cerebrovascular diseases on the potential health hazards. Therefore, a reasonable improvement in milk fat composition, improve milk quality in dairy production has been the subject focus of concern. Therefore this study aims to use milk somatic cell study different lactation mammary fat synthesis genes, affecting milk fat synthesis to elucidate the molecular mechanism of intrinsic factors and provide a theoretical basis for the optimization of raw milk of ruminants, especially milk fat Nutritional regulation and genetic improvement to provide a theoretical basis. The main results are as follows: Preparation of milk somatic cells: the colostrum, milk and regular milk late as the research object, by direct microscopic examination and blood count plate method and trypan blue staining on the SCC were identified, extracted reference Puissant milk somatic cells RNA, by electrophoresis and UV spectrophotometer RNA purity, integrity and content of testing, RT-PCR method for detection of the housekeeping gene GAPDH. The results showed that: SCC about 10 ~ 183,000 / ml between the state proved to be taken from the milk of healthy body cells. Activity between about 60 to 67.5%, RNA extraction OD260/OD280 value between 1.65 to 2.0, the content is between 0.6 ~ 1.0mg/ml in a housekeeping gene GAPDH 452bp at the target band. Show successfully prepared milk somatic cells. Mammary fat synthesis related gene expression: the colostrum, milk and regular milk in the milk late somatic cells for the study, housekeeping gene GAPDH as an internal, on milk LPL, CD36, VLDLR, ACSS2, ACSL1, FABP3, SCD , ACC, FASN, ADFP, XDH and BTN1A1 mRNA for semi-quantitative RT-PCR analysis. The results showed that, LPL, CD36, VLDLR, ACSS2, ACSL1, FABP3, SCD, ADFP, XDH and BTN1A1 mRNA in colostrum, milk and regular milk were expressed at the end, while ACC, FASN expression only in the colostrum, normal milk and the end of the milk was not detected. Compared with colostrum, milk, and often end milk LPL, CD36, VLDLR, ACSS2, ACSL1, FABP3, SCD, ADFP, XDH and BTN1A1mRNA transcription levels were significantly lower (P lt; 0.05), and the end of normal milk and milk no significant difference between (P gt; 0.05). These results are basically consistent lactation curve, suggesting that breast milk fatty acid synthesis dependent phase synthesis was significantly higher than the colostrum period and the end of the weaning period usually breast milk.
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