The yield, fatty acid composition and physical properties of milk fat obtained by feeding soya oil to dairy cows

1980 ◽  
Vol 31 (4) ◽  
pp. 368-374 ◽  
Author(s):  
William Banks ◽  
John L. Clapperton ◽  
Morag E. Kelly ◽  
Agnes G. Wilson ◽  
Robert J. M. Crawford
1976 ◽  
Vol 43 (2) ◽  
pp. 219-227 ◽  
Author(s):  
W. Banks ◽  
J. L. Clapperton ◽  
Morag E. Ferrie

SummaryThe effects on the fatty acid composition of milk fat of feeding various oil-enriched diets (soya oil, red palm oil/palmitic acid and tallow) to dairy cows receiving a fat-deficient basal diet are reported. It was found that a linear relation was obtained between the dietary intake of C18 fatty acids and their output in milk fat. A similar relation, applicable only to the oil-rich diets, was found for the C16 acids. The significance of these relations is discussed. Fatty acid compositions and yields are discussed and compared with literature examples in which similar oil-rich diets were fed, but in which the low amount of fat in the basal diet did not markedly depress milk yield. The proportion of trans-isomer in the octadecenoic acid was found to increase appreciably on feeding soya oil, and to a lesser extent with dietary tallow. A linear relation between the 18:0 and 18:1 contents of milk fat was found, and its significance is discussed.


2000 ◽  
Vol 25 ◽  
pp. 149-154
Author(s):  
B.F. McNamee ◽  
A.M. Fearon ◽  
J. Pearce

AbstractThe experiment was designed to investigate the effect of increasing the concentration of Cu2+ in the diet of the lactating dairy cow with a view to stimulating the activity of the mammary gland △9–desaturase enzyme system to increase the C18:1/18:0 ratio in the milk fat.In a preliminary study, two lactating dairy cows were provided with ground rapeseed/maizebased concentrates containing either a normal or a high concentration of supplementary Cu2+, the animal offered the normal concentration supplement was also provided with an oral CuSO4 solution drench so that both animals received an equal daily supply of Cu2+. Daily blood samples were collected from the cows and total plasma Cu2+ concentration was determined. A blood plasma lipid analysis was also carried out. In a second study, eight lactating dairy cows were provided with a silage and concentrate diet. The lipid portion of the concentrates was provided by either ground or unground rapeseed while the Cu2+ in the mineral supplement of the unground rapeseed-based concentrate was manipulated to provide one of the following three concentrations of Cu2+ in the concentrate (mg/kg DM); <10, 50 or 100. The subsequent milk fat was analysed for fatty acid composition.Presentation of an increased concentration of Cu2+ to the cow was more efficiently absorbed when provided in the concentrate mix than when provided as a CuSO4 solution in an oral drench. Increased dietary Cu2+ in the concentrates was successful at increasing the concentration of plasma Cu2+ from a normal concentration of 80–100 mg/cm3 to over 200 mg/cm3. An increased concentration of Cu2+ in the blood of the cows in the first experiment resulted in a significant increase (P<0·05) in the C18:1 content of the plasma lipid, possibly through the increased activity of the intestinal △9–desaturase enzyme system.The composition of the milk, including the fatty acid composition of the milk fat, from the second experiment was unaffected by the concentration of Cu2+ in the diet of the dairy cows within the concentration range of <10 to 35 mg/kg DM per day.


2003 ◽  
Vol 2003 ◽  
pp. 22-22
Author(s):  
D. I. Givens ◽  
C. Rymer ◽  
A.R. Moss ◽  
R. Allison

There is much interest in the manipulation of the fatty acid composition of milk fat so as to improve its health characteristics in the human diet. In an earlier study there was an indication that the concentration of fatty acids in milk may change with time when feeding whole oilseeds rich in polyunsaturated fatty acids (PUFA). In particular a tendency for an increase in CLA and C18:1 and a reduction in C18:2 and C18:3 concentrations with time were seen. The present study was therefore undertaken to examine the changes in the fatty acid composition of milk from high yielding dairy cows fed diets rich in monounsaturated fatty acids (MUFA) or PUFA over an extended period.


2003 ◽  
Vol 70 (3) ◽  
pp. 257-265 ◽  
Author(s):  
Chakra Wijesundera ◽  
Zhiping Shen ◽  
William J Wales ◽  
Dawn E Dalley

Two experiments were undertaken to determine the effects of cereal grain and fibre (hay or straw) supplements on the fatty acid composition of milk fat of grazing dairy cows in early lactation. In both experiments, grain supplements significantly increased (P<0·05) the proportion of the endogenously synthesized 10[ratio ]0–16[ratio ]0 fatty acids. Of the C18 acids, the proportion of 18[ratio ]0 and 18[ratio ]3 was significantly decreased (P<0·05) by grain supplementation, while that of 18[ratio ]2 was significantly increased (P<0·05). Irrespective of diet, 18[ratio ]1 trans-11 was the most dominant trans 18[ratio ]1 isomer in milk fat. In the first experiment, the proportions of the 18[ratio ]1 trans-11 isomer and conjugated linoleic acid (CLA, 18[ratio ]2 cis-9, trans-11) were highest for the pasture-only diets, and significantly (P<0·05) decreased with grain supplementation. The opposite result was observed in the second experiment, conducted in a different dairy region, suggesting that factors such as the quality of pasture on offer and the physiological state of the cow could affect the content of CLA and trans fatty acids in milk fat. In both experiments, there was a significant positive linear relationship between CLA and 18[ratio ]1 trans-11. Fibre supplements had little effect on the fatty acid composition of the milk.


1990 ◽  
Vol 57 (3) ◽  
pp. 295-306 ◽  
Author(s):  
John J. Murphy ◽  
Gerald P. McNeill ◽  
James F. Connolly ◽  
Patrick A. Gleeson

SummaryTwo experiments were carried out to determine the effect on milk yield, milk composition and composition and physical properties of milk fat of giving full fat soyabeans (FFS) and full fat rapeseeds (FFR) to dairy cows. In both experiments grass silage was provided ad lib. and constituted over 50% of the dry matter (DM) intake of the cows. In experiment 1, cows received 7·25 kg/d of a concentrate mixture containing 240 g/kg of extruded FFS or 7·25 kg/d of a mixture without soyabeans. Cow performance was not significantly affected by the inclusion of FFS but fatty acid composition of the milk fat was greatly altered. The contents of C8:0 to C16:0 were significantly reduced (P < 0·001) while the contents of C18:0, C18:l and C18:2 were significantly increased (P < 0·001). Milk fat produced during feeding on FFS concentrate had a significantly lower content of solid fat at temperatures between 0 and 25 °C compared with milk fat produced when FFS was not given. In experiment 2, cows received concentrate mixtures containing either no whole rapeseed, 150 g/kg of whole unground FFR or 150 g/kg of ground FFR. Milk yield was significantly higher and silage DM intake significantly lower with the ground FFR concentrate compared with the other two diets but milk composition was not significantly different among treatments. FFR inclusion, either ground or unground, reduced diet digestibility. Changes in fatty acid composition of the milk fat were similar to those observed with FFS inclusion but the effect was larger with ground FFR compared with unground FFR. Nuclear magnetic resonance analysis showed a lower solid fat content when the FFR diets were employed with the effect being greatest with ground FFR.


1982 ◽  
Vol 53 (7) ◽  
pp. 499-502
Author(s):  
Hisao ITABASHI ◽  
Takeru KOBAYASHI ◽  
Noriaki YAMAGISHI ◽  
Hiroaki SHISHIDO

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