Study On Conjugated Linoleic Acid Milk And Its Function Of Reducing Fat

The present experiment was designed to study the effect of different diets on conjugated linoleic acid(CLA) content of rumen liquor and milk by invivo and in vitro, discuss the effect of different diets on milk composition and performance of cow, and obtain CLA milk. In addition, The efficacy reducing fat of fortified and biosynthesis CLA milk were studied .1. Effect of different diets on CLA content of rumen cultivate liquor in vitroTo select the best factors increasing the CLA content of rumen liquor in vitro, the five factors quadratic rotary combination design was used. The result was that the main factor to enhance CLA content of cultivate liquor that percentages of forage, percentages of Soybean meal and cottonseed meal, sunflower oil in diets. The best factors to increase the CLA content of rumen liquor was that supplemented with 70% forage, 5% sunflower oil, 11% Soybean meal and 14% cottonseed meal in diets and pH 7.0 . The model of diet factor (X) and CLA content (Y) wasY=0.35647+0.0585X₁-0.02325X₂+0.02083X₄+0.01088X₁X₄-0.03779X₂²-0.01829X₃² -0.06654X₄² R²=87.41.2. Effect of adjusted composition of feed on CLA content in milk and performance of cowA 3 x 3 Latin square design were used to determine the effect of different diets on milk composition and conjugated linoleic acids (CLA) content in milk. Nine Holstein cows were fed diets containing supplemental 5%Sunflower seed Oil (SSO) or 3%SSO plus 2%soybean oil (SBO) in combination. When supplemented 5% SSO or 3%SSO plus 2%SBO in feed, the CLA content in milk were increased, while dry matter intake, percentages of fat, protein milk , and DM were reduced, lactose concentration, density, and PH did not be affected. In addition, milk yield were increased when 5% SSO or 3%SSO plus 2%SBO were fed, In contrast, 4% milk yield were decreased. Feeding 5% SSO or 3%SSO plus 2%SBO could increase short and middle fatty acid concentrations, reduce UPLA concentrations of long fatty acid, but decrease C18:0 fatty acid concentrations.3. Effects of fortified CLA milk on fat deposition in miceTo study the effects of fortified conjugated linoleic acid milk on body fat and plasma lipids in mice, the four week old male Kunming mice were randomly divided into four groups and fed diet and milk supplemented with 0%,0.1%,0.5%,1.0% conjugated linoleic acid (percent of diet DM)respectively for four weeks. Weight gain, body fat, intra-abdominal fat , feed conversion efficiency and plasma TG, TC ,HDL ,LPL were measured. At the end of the experiment, weight gain , body fat, intra-abdominal fat and feed conversion efficiency were decreased with increasing CLA in the milk and were lower significantly (p<0.05) than that of control group when supplemented with 0.5% CLA in milk. The concentration of TG, TC and TC- HDL/ HDL were decreased, but HDL and LPL were increased with increasing CLA amount in the milk .It was the best to TG, HDL ,LPL and TC- HDL/ HDL when mice were fed the milk supplemented with 1.0% CLA ,and TC was the lowest in the milk supplemented with0.5% CLA .4. Effects of fortified and biosynthesis CLA milk on fat deposition in miceTo study the effects of fortified and biosynthesis conjugated linoleic acid milk on body fat and plasma lipids in mice. The four week old male Kunming mice were randomly divided into three groups and fed diet and milk not supplemented , supplemented with fortified and biosynthesis conjugated linoleic acid (percent of diet DM)respectively for four weeks. Weight gain, body fat, intra-abdominal fat, feed conversion efficiency and plasma TG, TC ,LDL,HDL ,LPL and LSP were measured. At the end of the experiment, weight gain , body fat, intra-abdominal fat and the concentration of plasma TG, TC LDL,TC- HDL/ HDL were decreased(p<0.05 ), but HDL,LSP (p<0.05 )and LPL(p>0.05 ) were increased than that of control group when mice were fed with fortified and biosynthesis CLA milk .Fed biosynthesis CLA milk may significantly (p<0.05) decrease concentration of plasma TC, LDL/HDL and increase HDL, LSP than that of Fed fortified CLA milk group ,but Weight gain, body fat, intra-abdominal fat , feed conversion efficiency and concentration of plasma TG, LDL and LPL were not significantly (p>0.05).