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D E Bauman - One of the best experts on this subject based on the ideXlab platform.

  • a supplement containing trans 10 cis 12 conjugated linoleic acid reduces Milk Fat Yield but does not alter organ weight or body Fat deposition in lactating ewes
    Journal of Nutrition, 2010
    Co-Authors: L A Sinclair, Michael J De Veth, Weerasinghe M P B Weerasinghe, R G Wilkinson, D E Bauman
    Abstract:

    Conjugated linoleic acids (CLA) have been demonstrated to be a potent inhibitor of Milk Fat synthesis in ruminants, but effects on carcass composition and organ weight are unknown. Our objectives in this experiment were to determine the dose response of ruminally protected CLA on the performance, organ weight, and Fatty acid (FA) composition of early lactation dairy ewes. Twenty-four multiparous dairy ewes were fed a basal diet for 10 wk that was supplemented with a lipid-encapsulated CLA at 1 of 3 levels: no CLA (control, CON), low CLA (L-CLA), or high CLA (H-CLA) to supply 0, 1.5, or 3.8 g/d, respectively, of both trans-10, cis-12 and cis-9, trans-11 CLA. Dry matter intake was not affected (P . 0.05) by dietary treatment. Ewes fed H-CLA had a 13% higher Milk Yield compared with those receiving either CON or L-CLA. Compared with CON, Milk Fat Yield (g/d) was 14 and 24% lower in ewes fed L-CLA or H-CLA, respectively. Supplementing ewes with CLA did not affect carcass or organ weights, carcass composition, or organ FA content. Compared with ewes receiving the CON diet, CLA supplementation had little effect on the FA composition of the Longissimus dorsi, although cis-9, trans-11 and trans-10, cis-12 CLA were increased in ewes receiving H-CLA. The current findings are consistent with the view that the energy spared by the CLA reduction in Milk Fat content was mainly partitioned to Milk Yield and there was no evidence of organ hypertrophy or liver steatosis. J. Nutr. doi: 10.3945/jn.110.126490.

  • a conjugated linoleic acid supplement containing trans 10 cis 12 conjugated linoleic acid reduces Milk Fat synthesis in lactating goats
    Journal of Dairy Science, 2008
    Co-Authors: A L Lock, T.a. Gipson, M J De Veth, M Rovai, D E Bauman
    Abstract:

    The effect of conjugated linoleic acid (CLA) supplements containing trans-10, cis-12 for reducing Milk Fat synthesis has been well described in dairy cows and sheep. Studies on lactating goats, however, remain inconclusive. Therefore, the current study investigated the efficacy of a lipid-encapsulated trans-10, cis-12 CLA supplement (LE-CLA) on Milk production and Milk Fatty acid profile in dairy goats. Thirty multiparous Alpine lactating goats in late lactation were used in a 3 x 3 Latin square design (14-d treatment periods separated by 14-d intervals). Does were fed a total mixed ration of Bermuda grass hay, dehydrated alfalfa pellets, and concentrate. Does were randomly allocated to 3 treatments: A) unsupplemented (control), B) supplemented with 30 g/d of LE-CLA (low dose; CLA-1), and C) supplemented with 60 g/d of LE-CLA (high dose; CLA-2). Milk Yield, dry matter intake, and Milk protein content and Yield were unaffected by treatment. Compared with the control, Milk Fat Yield was reduced 8% by the CLA-1 treatment and 21% by the CLA-2 treatment, with Milk Fat content reduced 5 and 18% by the CLA-1 and CLA-2 treatments, respectively. The reduction in Milk Fat Yield was due to decreases in both de novo Fatty acid synthesis and uptake of preformed Fatty acids. Milk Fat content of trans-10, cis-12 CLA was 0.03, 0.09, and 0.19 g/100 g of Fatty acids for the control, CLA-1, and CLA-2 treatments, respectively. The transfer efficiency of trans-10, cis-12 CLA from the 2 levels of CLA supplement into Milk Fat was not different between treatments and averaged 1.85%. In conclusion, trans-10, cis-12 CLA reduced Milk Fat synthesis in lactating dairy goats in a manner similar to that observed for lactating dairy cows and dairy sheep. Dose-response comparisons, however, suggest that the degree of reduction in Milk Fat synthesis is less in dairy goats compared with dairy cows and dairy sheep.

  • effect of supplementation with calcium salts of fish oil on n 3 Fatty acids in Milk Fat
    Journal of Dairy Science, 2007
    Co-Authors: E Castanedagutierrez, D A Dwyer, A L Lock, M J De Veth, K D Murphy, D E Bauman
    Abstract:

    Abstract Enrichment of Milk Fat with n-3 Fatty acids, in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), may be advantageous because of their beneficial effects on human health. In addition, these Fatty acids play an important role in reproductive processes in dairy cows. Our objective was to evaluate the protection of EPA and DHA against rumen biohydrogenation provided by Ca salts of fish oil. Four Holstein cows were assigned in a Latin square design to the following treatments: 1) ruminal infusion of Ca salts of fish oil and palm Fatty acid distillate low dose (CaFO-1), 2) ruminal infusion of Ca salts of fish oil and palm Fatty acid distillate high dose (CaFO-2), 3) ruminal infusion of fish oil high dose (RFO), and 4) abomasal infusion of fish oil high dose (AFO). The high dose of fish oil provided ∼16 and ∼21g/d of EPA and DHA, respectively, whereas the low dose (CaFO-1) provided 50% of these amounts. A 10-d pretreatment period was used as a baseline, followed by 9-d treatment periods with interceding intervals of 10 d. Supplements were infused every 6h, Milk samples were taken the last 3 d, and plasma samples were collected the last day of baseline and treatment periods. Milk Fat content of EPA and DHA were 5 to 6 times greater with AFO, but did not differ among other treatments. Milk and Milk protein Yield were unaffected by treatment, but Milk Fat Yield and DM intake were reduced by 20 and 15%, respectively, by RFO. Overall, results indicate rumen biohydrogenation of long chain n-3 Fatty acids was extensive, averaging >85% for EPA and >75% for DHA for the Ca salts and unprotected fish oil supplements. Thus, Ca salts of fish oil offered no protection against the biohydrogenation of EPA and DHA beyond that observed with unprotected fish oil; however, the Ca salts did provide rumen inertness by preventing the negative effects on DM intake and Milk Fat Yield observed with unprotected fish oil.

  • trans 9 cis 11 conjugated linoleic acid reduces Milk Fat synthesis in lactating dairy cows
    Journal of Dairy Science, 2007
    Co-Authors: James W Perfield, Adam L. Lock, J. Mikko Griinari, Asgeir Saebo, Pierluigi Delmonte, D A Dwyer, D E Bauman
    Abstract:

    Abstract Under certain dietary situations, rumen biohydrogenation results in the production of unique Fatty acids that inhibit Milk Fat synthesis. The first of these to be identified was trans -10, cis -12 conjugated linoleic acid (CLA), but others are postulated to contribute to diet-induced Milk Fat depression (MFD). Our objective was to examine the potential role of trans -9, cis -11 CLA in the regulation of Milk Fat. In a preliminary study, we used gas-liquid and high-performance liquid chromatography techniques to examine Milk Fat samples from a diet-induced MFD study and found that an increase in trans -9, cis -11 CLA corresponded to the decrease in Milk Fat Yield. We investigated this further using a CLA enrichment of 9, 11 isomers to examine the biological effect of trans -9, cis -11 CLA on Milk Fat synthesis. Four rumen-fistulated Holstein cows were randomly assigned in a 4×4 Latin square experiment involving 5-d treatment periods and abomasal infusion of 1) ethanol (control), 2) a 9, 11 CLA mix (containing 32% trans -9, cis -11, 29% cis -9, trans -11, and 17% trans -9, trans -11), 3) a trans -9, trans -11 CLA supplement, and 4) a trans -10, cis -12 CLA supplement (positive control). The trans -9, trans -11 CLA and trans -10, cis -12 CLA supplements were of high purity (>90%), and all supplements were infused at a rate to provide 5 g/d of the CLA isomer of interest. Milk Yield and dry matter intake did not differ among treatments. Compared with the control treatment, Milk Fat Yield was reduced by 15% for the 9, 11 CLA mixture and by 27% for the trans -10, cis -12 CLA treatment. We also found that trans -9, trans -11 CLA had no effect on Milk Fat Yield, and previous research has shown that Milk Fat Yield is unaltered when cows are infused with cis -9, trans -11 CLA. When all treatments were considered, results suggested that trans -9, cis -11 was the CLA isomer in the 9, 11 CLA mix responsible for the reduction in Milk Fat synthesis, although the magnitude was less than that observed for trans -10, cis -12 CLA. Interestingly, trans -9, trans -11 CLA altered the Milk Fat desaturase index, further demonstrating that alterations in desaturase can occur independently of effects on Milk Fat synthesis. Overall, our investigations identified that an increase in Milk Fat content of trans -9, cis -11 CLA was associated with diet-induced MFD and provided evidence of a role for this isomer in MFD based on the 15% reduction in Milk Fat Yield with abomasal infusion of a CLA enrichment that supplied 5 g/d of trans -9, cis -11 CLA.

  • short communication regulation of Milk Fat Yield and Fatty acid composition by insulin
    Journal of Dairy Science, 2006
    Co-Authors: B A Corl, S T Butler, W R Butler, D E Bauman
    Abstract:

    Abstract Diet-induced Milk Fat depression in dairy cows has been known for many years and several theories have been proposed. One that continues to receive support is the glucogenic-insulin theory. Previous studies testing this theory using a hyperinsulinemic–euglycemic clamp have had variable results attributable to variability in the use of body Fat reserves as a source of Milk Fatty acids. Our objective was to test the glucogenic-insulin theory using cows immediately postpartum, a period when the use of body Fat for Milk Fat synthesis is greatest. During wk 2 postpartum, 5 cows were given a 2-d baseline period and then clamped for 4 d. Insulin was increased more than 2-fold during the clamp while the blood glucose concentration was maintained. Milk Yield was not altered by administration of the clamp (38.7 vs. 39.0±1.4kg/d); however, the Milk Fat percentage and Yield were reduced by 27% and plasma nonesterified Fatty acids were reduced by 68%. Analysis of the Milk Fatty acid composition revealed that the decrease in Milk Fat Yield during use of the clamp was almost exclusively due to reductions in preformed Fatty acids; this is the exact opposite of what is observed with diet-induced Milk Fat depression. Therefore, our results do not support the glucogenic-insulin theory of diet-induced Milk Fat depression. The results further indicated that reductions in Milk Fat observed previously with hyperinsulinemic–euglycemic clamps or with glucose or propionate infusions were most likely consequences of the ability of insulin to inhibit lipolysis, thereby limiting the mammary availability of preformed Fatty acids mobilized from body reserves.

James W Perfield - One of the best experts on this subject based on the ideXlab platform.

  • trans 9 cis 11 conjugated linoleic acid reduces Milk Fat synthesis in lactating dairy cows
    Journal of Dairy Science, 2007
    Co-Authors: James W Perfield, Adam L. Lock, J. Mikko Griinari, Asgeir Saebo, Pierluigi Delmonte, D A Dwyer, D E Bauman
    Abstract:

    Abstract Under certain dietary situations, rumen biohydrogenation results in the production of unique Fatty acids that inhibit Milk Fat synthesis. The first of these to be identified was trans -10, cis -12 conjugated linoleic acid (CLA), but others are postulated to contribute to diet-induced Milk Fat depression (MFD). Our objective was to examine the potential role of trans -9, cis -11 CLA in the regulation of Milk Fat. In a preliminary study, we used gas-liquid and high-performance liquid chromatography techniques to examine Milk Fat samples from a diet-induced MFD study and found that an increase in trans -9, cis -11 CLA corresponded to the decrease in Milk Fat Yield. We investigated this further using a CLA enrichment of 9, 11 isomers to examine the biological effect of trans -9, cis -11 CLA on Milk Fat synthesis. Four rumen-fistulated Holstein cows were randomly assigned in a 4×4 Latin square experiment involving 5-d treatment periods and abomasal infusion of 1) ethanol (control), 2) a 9, 11 CLA mix (containing 32% trans -9, cis -11, 29% cis -9, trans -11, and 17% trans -9, trans -11), 3) a trans -9, trans -11 CLA supplement, and 4) a trans -10, cis -12 CLA supplement (positive control). The trans -9, trans -11 CLA and trans -10, cis -12 CLA supplements were of high purity (>90%), and all supplements were infused at a rate to provide 5 g/d of the CLA isomer of interest. Milk Yield and dry matter intake did not differ among treatments. Compared with the control treatment, Milk Fat Yield was reduced by 15% for the 9, 11 CLA mixture and by 27% for the trans -10, cis -12 CLA treatment. We also found that trans -9, trans -11 CLA had no effect on Milk Fat Yield, and previous research has shown that Milk Fat Yield is unaltered when cows are infused with cis -9, trans -11 CLA. When all treatments were considered, results suggested that trans -9, cis -11 was the CLA isomer in the 9, 11 CLA mix responsible for the reduction in Milk Fat synthesis, although the magnitude was less than that observed for trans -10, cis -12 CLA. Interestingly, trans -9, trans -11 CLA altered the Milk Fat desaturase index, further demonstrating that alterations in desaturase can occur independently of effects on Milk Fat synthesis. Overall, our investigations identified that an increase in Milk Fat content of trans -9, cis -11 CLA was associated with diet-induced MFD and provided evidence of a role for this isomer in MFD based on the 15% reduction in Milk Fat Yield with abomasal infusion of a CLA enrichment that supplied 5 g/d of trans -9, cis -11 CLA.

  • trans 10 trans 12 conjugated linoleic acid does not affect Milk Fat Yield but reduces δ9 desaturase index in dairy cows
    Journal of Dairy Science, 2006
    Co-Authors: James W Perfield, Adam L. Lock, Pierluigi Delmonte, Martin P Yurawecz, D E Bauman
    Abstract:

    Abstract Trans -10, cis -12 conjugated linoleic acid (CLA) is a potent inhibitor of Milk Fat synthesis, and the magnitude of Milk Fat depression is often correlated with the Fat content of this isomer. However, the trans -10, cis -12 CLA content does not always correspond to the extent of Milk Fat depression, and in some instances, an increase in the Milk Fat content of trans -10, trans -12 CLA has been observed. We synthesized trans -10, trans -12 CLA (>90% purity) and investigated its effect on Milk Fat synthesis and incorporation into plasma lipids. Three rumen-fistulated Holstein cows were randomly assigned in a 3×3 Latin square experiment. Treatments were a 4-d abomasal infusion of 1) ethanol (control), 2) a trans -10, cis -12 CLA supplement (positive control), and 3) a trans -10, trans -12 CLA supplement; 5 g/d of the CLA isomer of interest was provided. Milk Yield, dry matter intake, and Milk protein were unaffected by treatment. Treatment with trans -10, trans -12 CLA had no effect on Milk Fat Yield, whereas treatment with trans -10, cis -12 CLA reduced Milk Fat Yield by 28%. Incorporation of CLA was greatest for the plasma triglyceride fraction, and the Milk Fat content was subsequently elevated within the respective treatment groups. The Milk Fatty acid composition indicated that Δ 9 -desaturase was reduced significantly for both CLA treatments, but the reduction was greater for the treatment with trans -10, trans -12 CLA. Overall, abomasal infusion of trans -10, trans -12 CLA and trans -10, cis -12 CLA altered the desaturase ratios, but only trans -10, cis -12 CLA reduced Milk Fat synthesis.

  • Milk Fat synthesis is unaffected by abomasal infusion of the conjugated diene 18∶3 isomers cis-6, trans-10, cis-12 and cis-6, trans-8, cis-12
    Lipids, 2005
    Co-Authors: Asgeir Saebo, James W Perfield, Pierluigi Delmonte, Martin P Yurawecz, P. Lawrence, J. T. Brenna, D E Bauman
    Abstract:

    It has been previously established that trans -10, cis -12 CLA is a potent inhibitor of Milk Fat synthesis. Although the mechanism of this action is not completely understood, it has been speculated that eicosanoid-like metabolites of this isomer formed by the activity of tissue desaturases may be responsible for its activity. The objective of this study was to investigate the effects of an enrichment containing an 18∶3 conjugated diene, produced in the metabolism of trans -10, cis -12 CLA, on Milk Fat synthesis. Three rumen-fistulated Holstein cows (210±8 d in Milk) were randomly assigned in a 3×3 Latin square experiment. Treatments were (i) control, (ii) trans -10, cis -12 CLA supplement (2.1 g/d; positive control), (iii) enrichment providing two conjugated diene 18∶3 isomers (2.6 g/d of cis -6, trans -10, cis -12 and 4.0 g/d of cis -6, trans -8, cis -12) and trans -10, cis -12 CLA (2.1 g/d). Treatments were abomasally infused for 5 d at 4-h intervals, and there was a 7-d interval between periods. Milk Yield, dry matter intake, and Milk protein Yield were unaffected by treatments. In contrast, the trans -10, cis -12 CLA supplement reduced Milk Fat Yield by 27%, whereas the supplement enriched with conjugated diene 18∶3 isomers (treatment iii) had no effect on Milk Fat Yield beyond that attributable to its trans -10, cis -12 CLA content. The transfer efficiency of trans -10, cis -12 CLA into Milk Fat was 25 and 24% for treatments ii and iii, respectively. At the same time, the abomasally infused conjugated diene 18∶3 isomers were transferred to Milk Fat with an efficiency of 33 and 41% for cis -6, trans -10, cis -12 and cis -6, trans -8, cis -12 18∶3, respectively. Overall, short-term abomasal infusion of the conjugated diene 18∶3 isomers had no effect on Milk Fat synthesis, thereby offering no support for an involvement of metabolies of trans -10, cis -12 CLA in the regulation of Milk Fat synthesis.

  • use of conjugated linoleic acid cla enrichments to examine the effects of trans 8 cis 10 cla and cis 11 trans 13 cla on Milk Fat synthesis
    Journal of Dairy Science, 2004
    Co-Authors: James W Perfield, Asgeir Saebo, D E Bauman
    Abstract:

    Abstract Conjugated linoleic acid (CLA) supplements have typically been comprised of 4 isomers ( trans -8, cis -10; cis -9, trans -11; trans -10, cis -12; and cis -11, trans -13 CLA). Abomasal infusion of pure isomers has shown that trans -10, cis -12 CLA is a potent inhibitor of Milk-Fat synthesis, whereas cis -9, trans -11 CLA has no effect. However, there appear to be additional Fatty acids that inhibit Milk-Fat synthesis, and the objective of this study was to investigate the effects of additional CLA isomers present in CLA supplements. Four rumen fistulated Holstein cows (141±8 DIM, mean±SE) were randomly assigned in a 4×4 Latin square experiment. Treatments were abomasal infusion of (1) skim Milk (negative control), (2) trans -10, cis -12 CLA supplement (positive control), (3) trans -8, cis -10 CLA supplement, and (4) cis -11, trans -13 CLA supplement. Treatments 2 through 4 were targeted to provide 4 g/d of the CLA isomer of interest. The trans -8, cis -10 CLA supplement had no effect on Milk-Fat Yield, whereas the trans -10, cis -12 CLA supplement reduced Milk-Fat Yield by 35%. The cis -11, trans -13 CLA supplement contained some trans -10, cis -12 CLA, and when data were compared to the positive control treatment group, it was obvious that cis -11, trans -13 CLA also had no effect on Milk-Fat synthesis. Milk-Fat content of specific CLA isomers was significantly elevated within respective treatment groups. Milk Yield, DMI, and Milk protein Yield were unaffected by treatment. Overall, trans -10, cis -12 CLA reduced Milk-Fat synthesis, whereas the other major isomers present in CLA supplements ( trans -8, cis -10 CLA and cis -11, trans -13 CLA) had no effect.

G Cosso - One of the best experts on this subject based on the ideXlab platform.

  • association between srebp 1 gene expression in mammary gland and Milk Fat Yield in sarda breed sheep
    Meta Gene, 2013
    Co-Authors: V Carcangiu, Maria Consuelo Mura, C Daga, S Luridiana, Sara Bodano, G Sanna, M L Diaz, G Cosso
    Abstract:

    The aim of this study was to examine the expression patterns of SREBP-1 gene in Milk somatic cells and its association with Milk Fat Yield during early lactation in Sarda breed sheep. A sample of 20 Sarda ewes, aged between 4 and 5 years, in their third to fourth lactation were chosen. From each ewe 28 days after lambing Milk Yield was measured, and a 160 ml Milk sample for the RNA extraction and to test somatic cells count and lactose, Fat and protein contents were collected. From the obtained RNA, total cDNA was synthesized and the quantitative PCR was performed. The Fat, proteins and lactose content showed many differences among the animals, but these variations were no correlated with the Milk Yield. The SREBP-1 gene expression resulted higher in the high Milk Fat producing ewes. The correlation analysis showed that the SREBP-1 expression level is directly related to the amount of Milk Fat (g/die) (P < 0.001), while the total RNA obtained from each sample was found to be related to the somatic cells number (P < 0.001). Instead the expression of this gene showed no relations with the concentration of Fat in Milk. Our data highlight that in sheep SREBP-1 gene is expressed in the mammary gland during early lactation. Moreover, the positive relationship between SREBP-1 gene expression and the Milk Fat Yield suggests that SREBP-1 gene is required for the lipid synthesis in the sheep mammary gland.

  • Association between SREBP-1 gene expression in mammary gland and Milk Fat Yield in Sarda breed sheep.
    Meta Gene, 2013
    Co-Authors: V Carcangiu, Maria Consuelo Mura, C Daga, S Luridiana, Sara Bodano, G Sanna, M L Diaz, G Cosso
    Abstract:

    The aim of this study was to examine the expression patterns of SREBP-1 gene in Milk somatic cells and its association with Milk Fat Yield during early lactation in Sarda breed sheep. A sample of 20 Sarda ewes, aged between 4 and 5 years, in their third to fourth lactation were chosen. From each ewe 28 days after lambing Milk Yield was measured, and a 160 ml Milk sample for the RNA extraction and to test somatic cells count and lactose, Fat and protein contents were collected. From the obtained RNA, total cDNA was synthesized and the quantitative PCR was performed. The Fat, proteins and lactose content showed many differences among the animals, but these variations were no correlated with the Milk Yield. The SREBP-1 gene expression resulted higher in the high Milk Fat producing ewes. The correlation analysis showed that the SREBP-1 expression level is directly related to the amount of Milk Fat (g/die) (P 

Y Chilliard - One of the best experts on this subject based on the ideXlab platform.

  • effect of linseed sunflower or fish oil added to hay or corn silage based diets on Milk Fat Yield and trans c18 1 and conjugated linoleic Fatty acid content in bovine Milk Fat
    Livestock Science, 2020
    Co-Authors: A Ferlay, Y Chilliard
    Abstract:

    Abstract It has been well established that Milk Fat Yield and composition are affected by different types of forage and lipid supplementation of cow diets, but there are very few direct comparisons, including different forages and lipid supplements. In this experiment, we analysed directly the interaction among 2 forage types and 3 types of lipid supplements on the responses of Milk Fat and Fatty acid Yields. Twelve Holstein cows were divided into 2 groups and received diets based on either mountain grassland hay (H, 60% of DM intake) or corn silage (C, 69%) and concentrate mixture. They were used in two replicated 3 × 3 Latin square designs (2 cows per block) to evaluate responses to feeding two basal diets (one for each Latin square) supplemented with either 2.5% fish oil (FO), 5.0% sunflower oil (SO), or 5.0% linseed oil (LO). Responses of Milk Fat and FA Yields were different according to the interaction between different types of forage and lipid supplementation. In fact, Milk Fat Yield was decreased by FO (when compared to other oils) with H diets, whereas it was decreased by LO with C diets. We observed a shift of trans11- to trans10-18:1 Yields, due to changes in ruminal biohydrogenation (RBH) pathway, after 2 weeks with CSO and CLO diets. The Milk 18:2n-6 Yield was increased to a larger extent with HSO than with CSO diets. Linseed oil supplementation increased more the trans13/14- and cis15-18:1, and 18:3n-3 Yields with H than with C diets. Linseed oil decreased more even saturated Fatty acids (FA) than SO or FO with C diets, whereas no change was observed with H diets. Effects on Milk FA Yields were more pronounced with C than H diets, notably with the shift of trans11- to trans10-18:1 with C diets. For a regular Milk production with a stable composition, the adaptation period for feeding a diet supplemented with vegetable lipids should be not lower than 3 weeks. We can conclude that the dose of vegetable oils that does not cause Milk Fat depression is under 5%. Finally, the Milk nutritional quality could be improved for HLO diet (versus other diets) with lower saturated FA (SFA) and higher Milk 18:3n-3 levels.

  • effects of diet and physiological factors on Milk Fat synthesis Milk Fat composition and lipolysis in the goat a short review
    Small Ruminant Research, 2014
    Co-Authors: Y Chilliard, Kevin J Shingfield, C Leroux, Pablo G Toral, J Rouel, L Bernard
    Abstract:

    The current short review summarizes recent data on the specificities of goats compared with cows, of Milk Fatty acid (FA) secretion and Milk Fat lipolysis responses to physiological and nutritional factors. The influence of lactation stage on Milk Fat Yield and FA composition is similar between goats and cows. In contrast, changes in Milk Fat Yield and composition to diet, lipid supplements in particular, differs between the two ruminant species. In almost all cases, dietary lipid supplements increase Milk Fat content in goats, but not in cows. The goat is much less sensitive to diet-induced alterations in ruminal biohydrogenation pathways causing trans-10 18:1 to replace trans-11 18:1 as the major intermediate relative to the cow. Mammary lipid secretion in the goat is also less sensitive to the anti-lipogenic effect of trans-10,cis-12 conjugated linoleic acid (CLA) compared with the cow. Consistent with these observations, mammary lipogenic gene expression is less affected by diets rich in starch and polyunsaturated FA (PUFA) in goats than cows. However, diets containing PUFA induce much greater changes in delta-9 desaturase gene expression in goats compared with cows, that may be related to differences in the availability of biohydrogenation intermediates at the mammary glands (e.g. trans-9,trans-11-CLA). The development of either goat flavour or rancidity is related to the inherent peculiarities of Milk FA composition and lipolytic system in this species. In contrast with cows, Milk LPL activity and lipolysis are low during early and late lactation in goats, and are decreased when animals are underfed or receive a diet supplemented with plant oils. In goats the alpha-s1-casein (CSN1S1) gene polymorphism is associated with a decrease in Milk Fat content and 8:0–12:0 concentrations in the low CSN1S1 genotype. Conversely, Milk Fat product/substrate concentration ratios for delta-9 desaturation and spontaneous lipolysis are increased in the low genotype.

  • expression and nutritional regulation of lipogenic genes in the ruminant lactating mammary gland
    Advances in Experimental Medicine and Biology, 2008
    Co-Authors: L Bernard, C Leroux, Y Chilliard
    Abstract:

    The effect of nutrition on Milk Fat Yield and composition has largely been investigated in cows and goats, with some differences for Fatty acid (FA) composition responses and marked species differences in Milk Fat Yield response. Recently, the characterization of lipogenic genes in ruminant species allowed in vivo studies focused on the effect of nutrition on mammary expression of these genes, in cows (mainly fed Milk Fat-depressing diets) and goats (fed lipid-supple- mented diets). These few studies demonstrated some similarities in the regulation of gene expression between the two species, although the responses were not always in agreement with Milk FA secretion responses. A central role for trans-10 C18:1 and trans-10, cis-12 CLA as regulators of Milk Fat synthesis has been proposed. However, trans-10 C18:1 does not directly control Milk Fat synthesis in cows, despite the fact that it largely responds to dietary factors, with its concentration being negatively correlated with Milk Fat Yield response in cows and, to a lesser extent, in goats. Milk trans-10, cis-12 CLA is often correlated with Milk Fat depression in cows but not in goats and, when postruminally infused, acts as an inhibitor of the expression of key lipogenic genes in cows. Recent evidence has also proven the inhibitory effect of the trans-9, cis-11 CLA isomer. The molecular mechanisms by which nutrients regulate lipogenic gene expression have yet to be well identified, but a central role for SREBP-1 has been outlined as mediator of FA effects, whereas the roles of PPARs and STAT5 need to be determined. It is expected that the development of in vitro functional systems for lipid synthesis and secretion will allow future progress toward (1) the identifica- tion of the inhibitors and activators of Fat synthesis, (2) the knowledge of cellular mechanisms, and (3) the understanding of differences between ruminant species.

  • relationship among trans and conjugated Fatty acids and bovine Milk Fat Yield due to dietary concentrate and linseed oil
    Journal of Dairy Science, 2005
    Co-Authors: Juan J Loor, A Ferlay, A Ollier, M Doreau, Y Chilliard
    Abstract:

    Abstract Effects on Fatty acid profiles and Milk Fat Yield due to dietary concentrate and supplemental 18:3n-3 were evaluated in 4 lactating Holstein cows fed a low- (35:65 concentrate:forage; L) or high- (65:35; H) concentrate diet without (LC, HC) added oil or with linseed oil (LCO, HCO) at 3% of DM. A 4×4 Latin square with four 4-wk periods was used. Milk Yield and dry matter intake averaged 26.7 and 20.2 kg/d, respectively, across treatments. Plasma acetate and β -hydroxybutyrate decreased, whereas glucose, nonesterified Fatty acids, and leptin increased with high-concentrate diets. Milk Fat percentage was lower in cows fed high-concentrate diets (2.31 vs. 3.38), resulting in decreases in Yield of 11 (HC) and 42% (HCO). Reduced Yields of 8:0-16:0 and cis 9-18:1 Fatty acids accounted for 69 and 17%, respectively, of the decrease in Milk Fat Yield with HC vs. LC (−90 g/d), and for 26 and 33%, respectively, of the decrease with HCO vs. LCO (−400 g/d). Total trans -18:1 Yield increased by 25 (HCO) and 59 (LCO) g/d with oil addition. Trans 10-18:1 Yield was 5-fold greater with high-concentrate diets. Trans 11-18:1 increased by 13 (HCO) and 19 (LCO) g/d with oil addition. Trans 13+14-18:1 Yield increased by 9 (HCO) and 18 (LCO) g/d with linseed oil. Yield of total conjugated linoleic acids (CLA) in Milk averaged 6 g/d with LC or HC compared with 14 g/d with LCO or HCO. Cis 9, trans 11-CLA Yield was not affected by concentrate level but increased by 147% in response to oil. Feeding oil increased Yields of trans 11, cis 13-, trans 11, trans 13-, and trans,trans -CLA, primarily with LCO. Trans 10, cis 12-CLA Yield (average of 0.08 g/d) was not affected by treatments. Yield of trans 11, cis 15-18:2 was 1 g/d in cows fed LC or HC and 10 g/d with LCO or HCO. Yields of cis 9, trans 11-18:2, cis 9, trans 12-18:2, and cis 9, trans 13-18:2 were positively correlated (r = 0.74 to 0.94) with Yields of trans 11-18:1, trans 12-18:1, and trans 13+14-18:1, respectively. Plasma concentrations of biohydrogenation intermediates with concentrate or linseed oil level followed similar changes as those in Milk Fat. Milk Fat depression was observed when HC induced an increase in trans 10-18:1 Yield. A correlation of 0.84 across 31 comparisons from 13 published studies, including the present one, was found among the increase in percentage of trans 10-18:1 in Milk Fat and decreased Milk Fat Yield. We observed, however, more drastic Milk Fat depression when HCO increased Yields of total trans -18:1, trans 11, cis 15-18:2, trans isomers of 18:3, and reduced Yields of 18:0 plus cis 9-18:1.

  • effect of different types of forages animal Fat or marine oils in cow s diet on Milk Fat secretion and composition especially conjugated linoleic acid cla and polyunsaturated Fatty acids
    Livestock Production Science, 2001
    Co-Authors: Y Chilliard, A Ferlay, M Doreau
    Abstract:

    Abstract This review summarises the known effects of forages, animal Fats or marine oils on bovine Milk Fat secretion and composition. Special attention is given to Fatty acids that could play a positive role for human health, such as butyric acid, oleic acid, C18 to C22 polyunsaturated Fatty acids and conjugated linoleic acid (CLA). The efficiency of the transfer of n-3 polyunsaturated Fatty acids from diet to Milk is reviewed. Milk Fat from pasture fed cows seems to be higher in linolenic acid than Milk Fat from cows receiving preserved grass or maize, but the magnitude of this difference is limited. Indirect comparisons show that Milk Fat from maize silage diets is richer in short-chain FA and linoleic acid when compared to grass silage diets. Compared to fresh grass, grass silage favours myristic and palmitic acids at the expense of mono- and polyunsaturated FA, including CLA. Protected tallow allows for a large increase in Milk Fat Yield, and in the percentage of Milk stearic and oleic acids, at the expense of medium chain FA. Non-protected tallow has a similar effect on medium chain FA without increasing so much C18 FA Yield, which explains that it does not increase Milk Fat Yield. Dose–response curves of Milk CLA are reviewed for marine oil supplements, as well as the relationship between Milk CLA and trans-C18:1 contents. The potential of marine oil supplementation to increase the mean CLA content in cow Milk Fat is large (more than 300% above basal values). A specific role for dietary C20:5 n-3 in the sharp decrease in Milk Fat secretion after fish oil supplementation is suggested. However, there is a need to evaluate how the different feeding strategies could change the other aspects of Milk Fat quality, such as taste, oxidative stability or manufacturing value.

H Rulquin - One of the best experts on this subject based on the ideXlab platform.

  • combined effects of trans 10 cis 12 conjugated linoleic acid propionate and acetate on Milk Fat Yield and composition in dairy cows
    Journal of Dairy Science, 2011
    Co-Authors: Gaelle Maxin, Frederic Glasser, C Hurtaud, J L Peyraud, H Rulquin
    Abstract:

    Abstract Diets inducing Milk Fat depression (MFD) are known to alter ruminal lipid metabolism, leading to the formation of specific isomers [such as trans -10, cis -12 conjugated linoleic acid (CLA)] that inhibit Milk Fat synthesis in lactating dairy cows. However, ruminal outflow of these isomers does not fully account for the decreases in Milk Fat synthesis observed during diet-induced MFD. The high-concentrate diets inducing MFD also induce a greater production of propionate, suggesting a possible inhibition of Milk Fat by propionate associated with trans -10, cis -12-CLA during MFD. The present experiment aimed to study the combined effects of propionate and trans -10, cis -12-CLA (both inhibitors of Milk Fat synthesis) on Milk Fat secretion and the effects of the combination of 2 nutrients with opposite effects (acetate and propionate). Six Holstein cows were used in a 6 × 6 Latin square design with 21-d periods (14 d of nutrient infusion). The treatments were control; ruminal infusion of 1,500 g/d of acetate (A); ruminal infusion of 800 g/d of propionate (P); duodenal infusion of 1.60 g/d of trans -10, cis -12-CLA (CLA); ruminal infusion of 750 g/d of acetate+400 g/d of propionate (A+P); and duodenal infusion of 1.60 g/d of trans -10, cis -12-CLA+ruminal infusion of 800 g/d of propionate (CLA+P). The amounts of nutrients infused were chosen to induce a similar variation in Milk Fat content. Treatments A and P decreased dry matter intake. Compared with the control, P and CLA treatments decreased Milk Fat content and Yield by 9% and 15% on average. Treatment A increased Milk Fat content by 6.5% but did not modify Milk Fat Yield (because of a decrease in Milk Yield). The effects of A and P, and CLA and P on Milk Fat and Fatty acid percentages and Yield were additive (A+P and CLA+P treatments). With a same dose of trans -10, cis -12-CLA, the additional supply of propionate induced a decrease in Milk Fat 40% higher than that induced by trans -10, cis -12-CLA alone. The Milk Fatty acid profile obtained with CLA+P was similar to those observed with high-concentrate diets inducing MFD. In conclusion, under our experimental conditions, the effects of the 3 nutrients were additive on mammary lipogenesis, regardless of their separate effects. We also show that propionate could contribute to the Milk Fat reductions unaccounted for by trans -10, cis -12-CLA during MFD induced by high-concentrate diets.