Milk composition and fatty acid profile of residual and available milk from ewes fed with diets supplemented with different vegetable oils (original) (raw)
Related papers
Journal of dairy …, 2010
Ruminant diet supplementation with sunflower oil (SO) and fish oil (FO) has been reported as a good strategy for enhancing some milk fat compounds such as conjugated linoleic acid (CLA) and n-3 polyunsaturated fatty acids in dairy cows, but no information is available regarding dairy sheep. In this work, ewe diet was supplemented with FO, alone or in combination with SO, with the aim of improving milk nutritional value and evaluating its effect on animal performance. Sixty-four Assaf ewes in mid lactation, fed a highconcentrate diet, were distributed in 8 lots of 8 animals each and assigned to 4 treatments (2 lots/treatment): no lipid supplementation (control) or supplementation with 20 g of SO/kg (SO), 10 g of FO/kg (FO), or 20 g of SO plus 10 g of FO/kg (SOFO). Milk production and composition, including a complete fatty acid profile, were analyzed on d 0, 3, 7, 14, 21, and 28 of treatments. Supplementation with FO tended to reduce dry matter intake compared with the control treatment (−15%), and its use in combination with SO (SOFO) resulted in a significant decrease in milk yield as well (−13%). All lipid supplements reduced milk protein content, and FO also reduced milk fat content by up to 21% alone (FO) and 27% in combination with SO (SOFO). Although the mechanisms involved in FO-induced milk fat depression are not yet well established, the observed increase in some milk trans-FA that are putative inhibitors of milk fat synthesis, such as trans-9,cis-11 CLA, and the 63% decrease in C18:0 (consistent with the theory of reduced milk fat fluidity) may be involved. When compared with the control, lipid supplementation remarkably improved the milk content of rumenic acid (cis-9,trans-11 CLA; up to 4-fold increases with SO and SOFO diets), whereas FO-containing diets also increased milk n-3 polyunsaturated fatty acids, mainly docosahexaenoic acid (with mean contents of 0.29 and 0.38% of total fatty acids for SOFO and FO, respective-ly), and reduced the n-6:n-3 FA ratio to approximately half the control value. All lipid supplements resulted in high levels of some trans-FA, mainly trans-11 C18:1 (vaccenic acid) but also trans-10 C18:1.
Variation in fatty acid composition of ewes' colostrum and mature milk fat
International Dairy Journal, 2010
Temporal content variations of approximately 70 C4eC24 fatty acids (FA) in colostrum and milk of ewes consuming winter diet were determined by gas chromatography. The content of monounsaturated, polyunsaturated and straight-chain saturated FA 14:0e16:0 in colostrum was higher whereas the content of 4:0e12:0, 18:0 and branched-chain saturated FA 15:0e17:0 was lower than that in mature milk. The effect of ewe breed on the FA profiles was not significant. The composition of FA changed most significantly 1e2 days after lambing in agreement with the time schedule of colostrum formation. Nevertheless, the content of FA further successively changed up to approximately the 6th day of lactation, whereas further changes up to the 60th day of lactation were smaller. This is consistent with the recommendation that ewes' milk is suitable for human consumption after six-to-eight days of lactation. The higher contents of palmitic and myristic acids in colostrum compared with mature milk suggest that FA composition in colostrum matches the changing needs of the growing lambs.
The present study investigated the effects of supplementing soybean oil (SBO) and sunflower oil (SFO) on the performance of early lactating Awassi ewes, growth of their sucking lambs and on the concentration of total fatty acids in milk and blood of suckling lambs. One hundred and twenty five ewes were randomly assigned into five equal sized treatment groups involved; a control total mixed ration (TMR) without added oil and four diets supplemented with 3 % SBO, 5 % SBO, 3 % SFO or 5 % SFO. Milk yield increased (P<0.05) in ewes fed 3 % SBO and 5 % SFO compared to control ewes. Milk protein content increased (P<0.05) in 3 % SBO, 3 % SFO and 5 % SFO groups in comparison to the control and 5 % SBO groups, whereas crude protein yield increased ((P<0.05) in 3 % and 5 % SFO groups compared to the control group. Plasma content of cholesterol in lamb was increased (P<0.05), while that of triglycerides was reduced (P<0.05). Supplementation with both oils reduced (P<0.05) short and medium chain fatty acids in milk fat but increased (P<0.05) C16:0, C17:1 and C18:0 content in milk fat. Supplementation also increased (P<0.05) the cis-9 trans-11 conjugated linoleic acid (CLA) content in milk fat. However, SFO produced higher (P<0.05) values than SBO. Both oils led to more (P<0.05) total CLA in the plasma of suckling lambs. In conclusion, supplementing a moderate dose of SBO or SFO to the diets increased CLA concentration in milk fat. Nevertheless, supplementation with SFO was more effective than that with SBO in increasing CLA concentration in milk fat and improving milk quality from the human health standpoint.
The Influence of Oil Addition on the Fatty Acid Composition of Sheep's Milk During Lactation
Agriculture and Forestry, 2023
The aim of this study was to determine the impact of plant sources of fat in food for sheep on the fatty acid composition of milk samples obtained from 210 sheep (herd of pure Pramenka and a herd of crossbred sheep) in the area of the Una Sana Canton. The studies were conducted in three periods: winter, spring and summer, and the herd is divided into experimental and control groups of sheep. Extruded flax seed has been added to nutrition in experimental group of sheep in every period of research in the amount of 3.5%. The total content of saturated fatty acids was the highest during the summer with the experimental group (70.75%), which plant sources of fat were added to. The most common saturated fatty acids in the analyzed samples of milk were: palmitic, myristic, stearic and lauric, whose values varied depending on the treatment of nutrition and research period. The differences found in the content of saturated fatty acids between the period of investigation of milk sample of experimental and the control group showed statistically very highly significant effect (p<0.001). The content of unsaturated fatty acids was the highest during the summer in the control group of sheep (32.00%). Of monounsaturated fatty acids mostly consisted of oleic during the summer period (25.60%) in the milk of the control group. Of polyunsaturated fatty acids, linoleic acid (3.6%) in the milk of control and α-linolenic (1.90%) of milk experimental group of sheep were the most prevalent in the winter. The lowest ratio of omega-6/omega-3 fatty acids in sheep's milk was achieved in the period of feeding sheep with old grass (July), 1.46% in the milk of the experimental group of sheep that were fed with concentrates in which omega-3 preparations were added.
The present study investigated the effects of supplementing the ration of ewes with soybean oil (SBO) or sunflower oil (SFO) on the performance of lactating ewes, sucking lambs, and on CLA and other fatty acids in milk. 125 Awassi ewes were assigned into 5 groups; a control diet (TMR) without added oil, and 4 diets supplemented with 3%SBO, 5%SBO, 3%SFO, or 5%SFO. The experiment started at lambing and lasted for 60 d, during which ewes were fed 1.5 kg per ewe per day from the TMR and had ad libtum access to alfalfa hay. Feeding diets rich in polyunsaturated fatty acids to lactating ewes resulted in increased (P<0.05) milk yield with clear effect in 3%SBO and 5%SFO fed ewes. Milk protein content and yield, as well as plasma content of cholesterol in lamb were increased (P<0.05), while that of triglycerides was reduced (P<0.05). Supplementation with both oils reduced (P<0.05) short and medium chain fatty acids in milk fat but increased (P<0.05) C16:0, C17:1 and C18:0 con...
Changes in the composition and fatty acid profile of Najdi ewes’ milk before and after weaning
South African Journal of Animal Science, 2017
This trial aimed to study the changes in the yield, composition, and fatty acid (FA) profile of ewes' milk during suckling and milking periods. Nineteen multiparous Najdi ewes were kept under identical management and feeding conditions during a 12-week trial that was divided into two periods. Milk samples were collected on each sampling day from the total yield during the suckling (3rd, 6th, and 9th week) and milking (12th week) periods. The milk yield and the total solids, fat, protein, and lactose contents of the milk remained constant throughout the suckling weeks, but the protein content increased and milk yield and lactose content decreased after weaning. There were no differences in milk saturated FA (SFA), unsaturated FA (UFA), and monounsaturated FA (MUFA) contents during the suckling and milking periods, whereas the polyunsaturated FA content increased during the milking period. There were no differences in the individual milk SFA during the weeks of suckling, but the contents of caproic acid (C6:0), caprylic acid (C8:0), margaric acid (C17:0), and stearic acid (C18:0) decreased. However, myristic acid (C14:0), lauric acid (C12:0), and isomers of pentadecanoic (C15:0) acid increased during the milking period. The percentage of vaccenic acid (C18:111t), rumenic acid (C18:29c,11t; conjugated linoleic acid (CLA)), ω-3 FA group, and the atherogenicity index did not differ during the suckling period, but increased after weaning in the 12th week of lactation. This study demonstrated that weaning lambs in Najdi ewes is probably a factor that strongly affects milk traits by changing yield, composition, and FA profile.
Addition of olive oil to dairy ewe diets: effect on milk fatty acid profile and animal performance
Journal of dairy science, 2008
The effects of ruminant diet supplementation with linoleic or different polyunsaturated fatty acids (FA) have been well documented. Less abundant information, however, exists on the effects of incorporating monounsaturated FA, such as oleic acid, on lipid metabolism or animal performance. The purpose of this work was to assess the effects of feeding dairy ewes a diet supplemented with high levels of olive oil (OO) on milk yield and composition, paying particular attention to the FA profile. Twenty-four Assaf ewes were fed ad libitum with 2 diets, control or supplemented with 6% OO (2 lots of 6 animals per diet) for 4 wk. Milk yield and composition and dry matter intake were recorded weekly. Milk FA composition was determined by gas chromatography and conjugated linoleic acid profile by silver ion HPLC. Milk yield increased in ewes receiving OO, with no differences in dry matter intake. The OO diet decreased the milk protein percentage but increased the milk fat, protein, and total s...
Quality improvement of Slovak ewe milk based on the content of health affecting fatty acid compounds
The content of 70 C4-C24 fatty acids (FA) in bulk milk samples of dairy ewes at 4 farms during pasture season and at one farm during winter season was determined by gas chromatography. The FA content in milk fat of grazed ewes was higher up to 4-fold for rumenic acid (CLA), 3-fold for trans-vaccenic acid (TVA) and 2-fold for α-linolenic acid (ALA) compared to that during winter diet. The content of CLA (3.5 %) and TVA (7.9 %) in milk fat of grazed ewes from Tajov farm was higher than that in milk of pasture grazed ewes or cows published previously. Nevertheless, the farm at Trenčianska Teplá because of lower altitude and corresponding climatic conditions in summer showed temporal variation up to 50 % lower content of CLA and TVA. The variations in CLA content during pasture season are primarily related to the seasonal changes of ALA content in pasture plants. These findings suggest that further development of ewes´ milk production should be situated in the northern part of Slovakia at higher altitudes thus providing better quality pastures and more consistent FA composition of ewe milk products with a high content of health affecting FA compounds. Ewe individuality is another important factor significantly affecting the FA milk fat content and also milk yield whereas the ewes´ breed and parity had only little effect. The effect of individuality, breeds and parity of grazed ewes based on FA content was investigated in herd of 148 Tsigai, 124 Improved Valachian and 56 Lacaune ewes grazing pasture and milk samples of individual ewes were taken on the same day. The CLA milk fat content varied up to 5-fold and milk yield up to 12-fold among individual ewes. An inverse relation between the milk yield and CLA content was observed which was not significant though. The ewes with a higher CLA milk fat content and a corresponding higher milk yield were considered in ewe selection for improving milk quality based on the content of health affecting FA compounds. Upon eliminating the data for 25 % ewes with a lower CLA milk fat content and lower milk yield the average CLA milk fat content increased by 10 % while keeping the milk yield.
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2009
The primary obiective of this trial was to evaluate the effect of energy and protein content in the diet on the FA profile of milk fat from ewes, especially polyunsaturated fatty acids Omega 3 (C18:3, EPA, C22:3, C22:5 and DHA) and CLA (conjugated linoleic acid C18:2 n-9c, 11t ). A secondary obiective was to effect with different level energy and protein on diet of caracteristics fermentation ruminal, yield and quality of sheep milk. Consequently, experimental diets were constituted by a 2 x 2 factorial arrangement of energy level in diets (Low – 0,90 UFL/kg DM vs. High – 0,97 UFL/kg DM) and protein level (Low – 14% CP vs. High – 16% CP). On a dry matter (DM) basis, forage: concentrate ratios were 73 : 27 (low energy diets) and 57 : 43 (high energy diets). Increased levels of protein and energy of diet in lactating sheep, influenced positively the quantitative and qualitative production of milk and, in particular, the profile of fatty acids. Nutritional quality of sheep milk has bee...
Advances in Animal Biosciences, 2010
Tropical pasture is the main source of cattle feed, but in the dry season it is deficient in protein, which is essential for microbial growth. The search for technology to increase animal performance may be a feasible alternative to reduce costs with dairy cattle nutrition. This work aimed to compare the performance and the efficiency of lactating cows on pasture, supplemented with concentrate containing 16% crude protein (CP) on dry matter basis using cottonseed meal with 38% CP as protein source, with or without a feed additive containing branched chain volatile fatty acids (Nutricattle). Twenty-four lactating Holstein × Gir crossbred cows were evaluated (average body weight = 436.5 kg, days in milk = 119, body condition score = 2.75, and average milk yield = 7.55 L/day). Animals were offered 1.0 kg/animal/day of concentrate in 2 milking times. In the first week, cows were fed the same diet. After the adaptation period, each lot was randomly assigned to feed the concentrate with or without 24 g of additive/cow/day. Data were analyzed in a randomized blocks design, including milk production and body condition score as covariates, using F test. Although there was a reduction in supplement intake in the fourth week, average milk yield of the additive treatment (8.3 L) was higher (P = 0.01) than the average milk yield of the control (7.3 L). There was no difference in the final body condition score between treatments (P = 0.48), but the additive increased 0.5 units during the experimental period. In relation to milk quality, no difference was observed in milk fat (P = 0.21) and cryoscopy (P = 0.71) between treatments. Therefore, although pastures usually have good quality during the rainy season, according to this result, the inclusion of Nutricattle additive was nutritionally efficient, increasing milk production by 12%.