Effects of different polyunsaturated fatty acid supplementations during the postpartum periods of early lactating dairy cows on milk yield, metabolic responses, and reproductive performances

Effects of dietary supplementation with omega-3 fatty acid-rich linseed on the reproductive performance of ewes in subtropical climates

The present study evaluated the effects of omega-3 (ω-3) fatty acid-rich linseed supplementation on the reproductive performance, endocrine profile, and biochemical profile of ewes reared in subtropical climates. Forty-eight acyclic and clinically healthy Marwari sheep, aged 1.5-2.5 years with no parity, were divided into four groups (n = n = 12 in each). Ewes in the control group (group I) were fed only a basal feed, whereas ewes in the treatment groups II, III, and IV were fed the basal diet along with 10%, 15%, and 20% linseed, respectively, daily on a dry matter basis. The experiment was conducted during the typical breeding season (October-November) of the sheep. The estrus induction rate was significantly higher (p < 0.05) in all treatment groups than in the control group. The estrus induction interval was significantly lower (p < 0.05) in group III. The conception rate in group I was significantly lower (p < 0.05). In addition, ewes in the control group had a significantly lower (p < 0.05) lambing rate than all treatment groups. Serum progesterone concentrations differed significantly (p < 0.05) between the control and the treatment groups on days 15, 30, 45, and 60 of supplementation. On treatment days 15 and 30, the serum estrogen concentrations were significantly higher (p < 0.05) in all treatment groups compared to that in group I. In all treatment groups, monounsaturated fatty acid (MUFA) decreased significantly (p < 0.05), whereas polyunsaturated fatty acid (PUFA) increased significantly (p < 0.05) from day 15 onward. In conclusion, by providing 15% dietary linseed supplementation to ewes, their reproductive performance can be improved in subtropical climates. Future studies are recommended to further elucidate the role of linseed supplementation in sheep reproduction in subtropical climates.

Effect of varying amounts of linseed oil or saturated fatty acids around insemination on reproductive and blood parameters of ewes

The current study was designed to evaluate the effect of sequential low and high dietary linseed oil (LO; as omega-3 enriched fatty acid; FA) before and post insemination, respectively, on different plasma variables of ewes. Fat-tailed Qezel ewes were assigned randomly to be fed a diet enriched with 3% LO (n = 30) or the saturated FA (SFA; n = 30) three weeks before insemination (Day 0). The lipogenic diet supplemented with 6% LO or SFA was fed after insemination until Day +21. The control ewes were fed an isocaloric and isonitrogenous diet with no additional FA during the study. Estrus was synchronized by inserting a vaginal sponge (Spongavet®) for 12 days + 500 IU equine chorionic gonadotropin (eCG; Gonaser®), and ewes were inseminated via laparoscopic approach 56-59 h after eCG injection. The size of ovarian structures was assessed by transvaginal ultrasonography at -21, -14, -2, 0, and +10 days. Blood samples were collected weekly to measure the plasma's different biochemical variables and FA profile. Treatment did not affect the amounts of glucose, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, interleukin-10, interleukin-2, and non-esterified FA (p > 0.05). Conversely, concentrations of triglyceride, cholesterol, tumor necrosis factor-alpha, and insulin-like growth factor-1 were higher in SFA-fed ewes relative to control animals (p < 0.05). LO feeding resulted in greater amounts of n-3 FA isomers in plasma, while higher amounts of stearic acid were detected in SFA fed group 0 and +21 (p < 0.05). The number of ovarian follicles and corpora lutea also were not affected by treatment. Other reproductive variables were not affected by treatment except for the reproductive rate. It seems that LO or SFA feeding of fat-tailed ewes peri-insemination period was not superior to the isocaloric non-additional fat diet provided for the control group during the non-breeding season.

Plasma fatty acid profile in Italian Holstein-Friesian dairy cows supplemented with natural polyphenols from the olive plant Olea Europaea L

This study evaluated the effects of supplementing with natural functional feed on the plasma fatty acid profile of lactating Italian Holstein-Friesian dairy cows. Thirty cows in mid-lactation received the natural olive extract PHENOFEED DRY (500 mg/cow/day) which mainly comprises hydroxytyrosol, tyrosol and verbascoside. The total content of polyphenols and the antioxidant power of standard feed, enriched feed and pure extract was evaluated respectively by Folin-Ciocalteu and DPPH assay, and a characterization in HPLC-UV (High-Performance Liquid Chromatography-Ultraviolet) of bioactive molecules present in the extract PHENOFEED DRY was performed. PHENOFEED DRY was provided for 60 days, and the plasma profile of fatty acids was determined by Gas Chromatography. The administration of enriched feed resulted in an increase in the ratio of Omega-6 to Omega-3 polyunsaturated fatty acids from 3:1 to 4:1 (p<0.001). This was not influenced by the calving order. The addition of polyphenols helped to keep monounsaturated (MUFA) and saturated (SFA) levels constant and results in a significant increase in polyunsaturated (PUFA) fatty acid after 15 days of administration. The Omega-6/Omega-3 ratio was in the optimal range. The findings show that inclusion of natural functional food such as plant polyphenols helps to maintain a healthy blood fatty acid profile in lactating dairy cows.

Impact of polyunsaturated fatty acid supplementation on assisted reproductive technology outcomes: a systematic review

This review explores the impact of polyunsaturated fatty acid (PUFA) supplementation in women undergoing assisted reproductive technology (ART) on reproductive outcomes. A systematic search of English peer-reviewed journals was carried out using MEDLINE, EMBASE, and the Cochrane Library to identify articles published from January 1978 to 2021. The primary outcomes assessed included pregnancy and live birth rates. Secondary outcome measures included: (i) implantation rate; (ii) fertilisation rate; (iii) number of oocytes retrieved; (iv) number of metaphase II (MII) oocytes; (v) blastocyst conversion; and (vi) embryo quality. A total of 4 randomised control trials (RCTs) met the inclusion criteria. There is a lack of high-quality research to support widespread dietary supplementation with PUFAs in women undergoing ART. Prior to its clinical recommendation, there is a need for well-designed RCTs to facilitate an in-depth understanding of PUFA supplementation in women undergoing ART.

Dietary n-3 PUFA augments pre-ovulatory follicle turnover and prolificacy in well-fed ewes

The present study evaluated the effect of dietary supplementation with n-3 polyunsaturated fatty acids (PUFA) on preovulatory follicle (POF) turnover, prolificacy, and endocrine and metabolic milieu in Malpura sheep. Fifty cyclic ewes with 3-3.5 body condition scores on a five-point scale were allocated equally to two groups (n = 25) following estrus synchronization and were supplemented with 0.6 mL/kg body weight of n-3 PUFA-rich fish oil (FO) or palm oil (PO) as control, for 60 d following an acclimatization period of 7 d. All ewes were mated with sexually active rams at the end of the supplementation period. On ultrasonographic ovarian scanning at the last fourth estrus, the mean number of POFs was 77.8% greater (P < 0.01) in FO ewes than in the PO ewes. The proportion of ewes with multiple ovulations two months after the beginning of supplementation was 56% in the FO group as compared to 8% in the PO group. The number of fetuses was 46% higher (P < 0.01) in the FO than in the PO ewes at d 45 of gestation. At lambing, the twinning percent in the FO ewes was three times greater than in the PO ewes (27.3 vs. 9.1%). Plasma cholesterol, estradiol, and insulin concentrations were lower (P < 0.01) in ewes fed with FO than those offered PO group at the end of the feeding period. It was concluded that the dietary supplementation of n-3 PUFA-rich FO in well-fed Malpura ewes improved the number of follicles and ovulation rate which led to an increased prolificacy, accompanied by a reduction of plasma cholesterols, estradiol, and insulin.

Preventive Supplementation of Vitamin E and Selenium as a Factor in Improving the Success Rate of Embryo Transfer in Cattle

The effects of stress on processes in the body are becoming an increasingly relevant research subject. The reproductive ability of bovine animals largely depends on these effects, whilst embryo transfer is increasingly being used as a reproduction method. In this study, we established the differences in the implantation ability of heifers that were treated (N=17) with selenium (Se) and vitamins AD3E, and non-treated heifers. Upon transfer, we took blood samples from both groups and used the total antioxidant status (TAS) value to analyze the presence of reactive oxygen species (ROS), the levels of non-esterified fatty acids (NEFA) and the levels of vitamin E and Se in blood plasma. In the study, we were able to demonstrate that preventive measures in the form of supplementation of vitamin E and Se, mitigate the effects of oxidative stress, strengthen the ability of an organism to improve the dynamic relationship between free radicals and antioxidants, improve the energy status of cattle, positively impact reproductive parameters and increase the success rate of embryo transfer. The difference in the number of successful embryo implantations between the control and treated group was statistically significant, with 64.7% of treated heifers being pregnant after embryo transfer and giving birth to healthy calves. In the control group, the implantation success rate was 41.2%. The supplementation of antioxidants in the form of a combination of vitamin AD3E and Se, proved to be a good method for strengthening the defense of an organism and an effective mean of preventive clinical approach for improving fertility parameters.

Effects of the donor factors and freezing protocols on the bovine embryonic lipid profile

Embryo lipid profile is affected by in vitro culture conditions, that lead to an increase in lipids. Efforts have been made to optimize embryo lipid composition as it is associated with their quality. The objective of this study was to evaluate whether the diet supplementation of donor cows (n-3 or n-6 PUFA), or the slow freezing protocols (ethylene glycol sucrose EG-S vs. glycerol trehalose GLY-TRE), or the physiological stage of the donor (nulliparous heifers vs. primiparous lactating cows) may impact the bovine embryo lipid profile. Lipid extracts of 97 embryos were individually analysed by liquid chromatography-high resolution mass spectrometry, highlighting 246 lipids including 85% being overabundant in cow embryos compared to heifer embryos. Among 105 differential lipids, 72 were overabundant after EG-S protocol, including a single glycerophosphate PA(32:1) representing 27.3% of the significantly modulated lipids, suggesting that it is degraded when GLY-TRE is used. No lipids were different according to the n-3 or n-6 supplementation of the donor cows. In conclusion, the embryonic lipid profile was mainly affected by the physiological stage of the donors and the slow freezing protocols. The overabundance of lipids in lactating cow embryos and the resulting lower quality of these embryos is consistent with the lower pregnancy rate observed in cows compared to heifers. Unlike GLY-TRE protocol, EG-S freezing allowed to preserve glycerophospholipids potentially improving the slow freezing of in vitro-produced embryos. Further studies are required to modulate embryo quality and freezability by modulating the lipidome and integrating all stages of embryonic production.

Effects of feeding rumen-protected linseed fat to postpartum dairy cows on plasma n-3 polyunsaturated fatty acid concentrations and metabolic and reproductive parameters

High-yielding dairy cows experience a negative energy balance and inflammatory status during the transition period. Fat supplementation increases diet energy density, and plasma n-3 polyunsaturated fatty acids (PUFA) have been proposed to improve immune function. This study tested the hypothesis that dietary supplementation with a rumen-protected and n-3 PUFA-enriched fat could ameliorate both the energetic deficit and immune status of postpartum high-yielding dairy cows, improving overall health and reproductive efficiency. At 11 d in milk (DIM), cows were randomly allocated to groups (1) n-3 PUFA (n = 29), supplemented with encapsulated linseed oil supplying additional up to 64 g/d (mean 25 ± 4 g/d) of α-linolenic acid (ALA), or (2) control (n = 31), supplemented with hydrogenated palm oil without ALA content. Fat supplements of the n-3 PUFA and control groups were available through an automated, off-parlor feeding system, and intake depended on the cow's feeding behavior. Plasma ALA concentrations were higher in n-3 PUFA than control cows, following a linear relation with supplement ingestion, resulting in a lower n-6/n-3 ratio in plasma. Metabolic parameters (body condition score and glucose and β-hydroxybutyric acid blood concentrations) were unaffected, but milk yield improved with increased intake of fat supplements. Plasma total adiponectin concentrations were negatively correlated with ingestion of n-3 PUFA-enriched fat supplement, following a linear relation with intake. Conception rate to first AI increased with higher intake of both fats, but a decrease of calving-to-conception interval occurred only in n-3 PUFA cows. Postpartum ovarian activity and endometrial inflammatory status at 45 DIM were unaffected. In conclusion, this study evinced a positive linear relation between rumen-protected linseed fat intake and plasma n-3 PUFA concentrations, which modulated adiponectin expression and improved reproductive parameters.

Peripheral leucocyte molecular indicators of inflammation and oxidative stress are altered in dairy cows with embryonic loss

Objective of experiment was to determine whether oxidative stress (OS) and inflammation altered embryonic loss in dairy cows. Blood samples were collected at days 0, 16, 32 and 60 after timed (AI) from 200 Holstein cows to determine embryonic loss based on interferon-stimulated gene-15 (ISG15) mRNA expression (day 16) and ultrasound at day 32 and day 60. Leucocyte expressions of mRNA TLR2, TLR4, TNF-α, IL1B, IL10, STAT3 (inflammation), PTGS2, PTGES (prostaglandin synthesis), and PLA2G4A and ALOX5AP (eicosanoid metabolism) at days 0 and 16 were determined. Plasma redox status for antioxidant enzymatic activities of glutathione peroxidase (GPX), superoxide dismutase (SOD), total antioxidant capacity (TAC), and concentrations of malondialdehyde (MDA) were determined at days 0, 16, 32 and 60. All antioxidant-redox responses were beneficially significant in pregnant cows diagnosed pregnant at day16 and sustained pregnancy to day 60 compared to non-pregnant cows at day16 or pregnant at day16 and lost embryos by days 32 or 60. The leucocyte mRNA expressions of TLR2, TLR4, STAT 3, IL1B, PTGS2, PLA2G4A and ALOX5AP were greater and PTGES was lower at day16 in pregnant cows that lost embryos early (P < 0.05). In conclusion peripheral leucocyte molecular indicators of inflammation and plasma indicators of OS were altered in pregnant cows undergoing embryonic losses compared to cows with a sustained pregnancy.

Reproductive Performance of Dairy Cows Fed a Diet Supplemented with n-3 Polyunsaturated Fatty Acids – A Review

The aim of this review is to summarize the current state of knowledge of reproductive performance of high-yielding dairy cows fed a diet supplemented with n-3 fatty acids (FA s), and to recommend a feeding schedule that can increase the success rate in reproduction. Dietary supplementation with fat, especially FA, has become an accepted strategy for supporting the fertility of high-yielding dairy cows. The two main categories of FA s, unsaturated fatty acids (UFA s) and saturated fatty acids (SFA s), exert distinct effects on reproductive functions, with UFA having a conclusively beneficial impact. Polyunsaturated fatty acids (PUFAs) are of particular importance on account of their biological properties. Standard feedstuffs (such as soybean) are rich in n-6 FA s, whereas few feedstuffs contain n-3 FA s. Neither the n-3 nor n-6 PUFA s are synthetized by the animal. Several field experiments have indicated that the recommended schedule of n-3 supplementation should last 160–170 days, from the eighth week before calving to 100 or 120 days postpartum. Supplementation of the diet thus covers the period from the late preantral stage of the follicle, the entire development of the antrum, oocyte ovulation, and fertilization, as well as the development of the preattachment embryo and its implantation. The following effects are among the important beneficial results of supplementation with n-3 FA s: a higher number of antral follicles suitable for ovum pick-up (OPU), larger dominant follicles and corresponding CL, better quality oocytes and embryos, and higher implantation rates resulting from improved uterine environment (e.g., reduced synthesis of luteolytic PGF2α). We conclude that dietary supplementation for high-yielding dairy cows with n-3 FA s supports ovarian functions and helps the embryo to survive in the adverse environment of the reproductive tract of the postpartum cow.

Effects of Flaxseed-rich Diet on Reproductive Performance in Estrous-synchronized Baluchi Ewes

The purpose of this study was to compare the effects of using different levels of flaxseed in diets on the reproductive performance of estrous-synchronized Baluchi ewes (para 3). Diets contained either basal diet (control) or different levels of extruded flaxseed (2%, 5%, 7%, 10%, and 12%) and were fed from lambing to 60 days after lambing. The ewe estrus cycles were synchronized using controlled internal drug release (CIDR) for 14 days starting from day 16 of fat supplementation. The rams were introduced 24 h after CIDR removal. The ewes fed control diets had the highest mean dry matter intake (1,800&amp;plusmn;35 g) which was declined with the increase of flaxseed levels. The experimental diets exerted no effects of urea concentration in blood plasma. However, plasma glucose concentration was lower (p &amp;lt;0.05) in the ewes fed the control diet and 2% flaxseed, compared to those in other groups. Nonetheless, there was no difference among the ewes fed 5%, 7%, 10%, and 12% flaxseed in terms of plasma glucose concentrations (p &amp;lt;0.05). The ewes fed 2% flaxseed had the highest level of plasma triglyceride concentration among other groups. In addition, the control group had the lowest level of plasma total cholesterol and low-density lipoproteins concentration in comparison to other groups (p &amp;lt;0.05). However, plasma nonesterified fatty acids and &amp;beta;-hydroxybutyrate concentrations were similar among the groups (P&amp;gt;0.05). The mean interval between CIDR removal and the exhibition of estrus ranged from 30 to 40 h with the shortest interval being recorded in the ewes fed 12% flaxseed (p &amp;lt;0.05). The control group had the lowest number of follicles on estrus day among other groups (p &amp;lt;0.05). Furthermore, the ewes fed 10% and 12% flaxseed had the highest ovulation, pregnancy, and lambing rates, compared to other groups (p &amp;lt;0.05). In conclusion, the findings revealed that feeding the ewes with 10% and 12% flaxseed resulted in the improvement of reproductive performance.

Effects of a n-3 polyunsaturated fatty acid-enriched diet on embryo production in dairy cows

Beneficial effects of n-3 polyunsaturated fatty acid (PUFA) supplementation on dairy cow reproduction have been previously reported. The objectives of the present study were to assess whether n-3 PUFA supplementation would affect in vitro embryo production (IVP) after ovarian stimulation. Holstein cows received a diet with 1% dry matter supplementation of either n-3 PUFA (n = 18, microencapsulated fish oil) or a control, n-6 PUFA (n = 19, microencapsulated soy oil). Both plasma and follicular fluid FA composition showed integration of total PUFA through the diet. All cows underwent an IVP protocol consisting of ovarian stimulation, ultrasound-guided transvaginal oocyte retrieval (ovum pick-up, OPU, five per cow) followed by in vitro maturation, fertilisation and 7 days of embryo development. A tendency toward an increase in the blastocyst rate (diet effect, P = 0.0865) was observed in n-3 cows, with 49.6 ± 5.5% vs 42.3 ± 5.5% in control n-6 cows. A significant increase (diet effect, P = 0.0217) in the good-quality blastocyst rate (freezable blastocysts) was reported in n-3 cows (42.2 ± 7.7%) compared to control n-6 cows (32.7 ± 7.7%). A significant difference in lipid composition was shown in the oocytes recovered by OPU from n-3 and n-6 treated cows, by intact single-oocyte MALDI-TOF mass spectrometry. The 42 differentially abundant identified lipids were mainly involved in cell membrane structure. In conclusion, n-3 PUFA supplementation enhanced oocyte quality and modified their lipid composition. Further studies are necessary to investigate the potential link of these lipid modifications with enhanced oocyte quality.

Effects of Extruded Linseed and Soybean Dietary Supplementation on Lactation Performance, First-Service Conception Rate, and Mastitis Incidence in Holstein Dairy Cows

This study quantifies the effects of extruded linseed and soybean (ELS) dietary supplementation on milk yield, composition, and fatty acid profiles, as well as first-service conception rate in Holstein dairy cows. Seventy-eight open Holstein dairy cows were divided into two groups: (1) a control, which received a basal diet; and (2) a test group, which received a basal diet supplemented with the ELS (650 g/kg of extruded linseed and 150 g/kg of extruded soybean) at a rate of 100 g/kg. In the ELS group, milk yield per day and solid not fat (SNF) yield increased by 3.26% and 0.88%, respectively, in relation to the control. Percentage milk fat decreased significantly by 1.4% in the ELS group when compared with the control. The ELS supplement resulted in a decrease in saturated fatty acids (SFAs) and an increase in monounsaturated (MUFAs) and polyunsaturated fatty acids (PUFAs) in milk. In conclusion, the supplementation of dairy cow feed with 100 g/kg of ELS increases milk yield and milk unsaturated fatty acids (especially MUFAs and PUFAs). ELS supplementation also causes a decrease in percentage fat and SFA levels but does not affect the first-service conception rate or the incidence rate of mastitis.

Long term dietary supplementation with microalgae increases plasma docosahexaenoic acid in milk and plasma but does not affect plasma 13,14-dihydro-15-keto PGF2α concentration in dairy cows

The aims of the study were to determine the long-term effects of dietary supplementation with microalgae (SCIM) on milk and blood fatty acid (FA) composition and reproductive hormones in early lactation dairy cows. Sixty Holstein-Friesian dairy cows (30 per treatment) were unsupplemented (Control) or supplemented with 100 g of SCIM (Schizochytrium limacinum sp.) per cow per day from 25 ± 0.5 d post-partum for 98 d. Intake and milk yield were recorded daily, with milk samples collected at weeks 0, 1, 2, 4, 8 and 14, and blood samples collected from 12 representative pairs per treatment at weeks 0, 2, 4, 8, and 14 for subsequent analysis of FA, β-hydroxybutyrate, non-esterified fatty acids and glucose. At 33 ± 0.9 d postpartum the oestrus cycle of 24 cows (12 per treatment) were synchronized and plasma 13,14-dihydro-15-keto PGF2α (PGFM) concentrations determined following an oxytocin challenge. Data were analysed by repeated measures analysis of variance. There was no effect of treatment on dry matter intake, milk yield or milk fat content, with mean values across treatments of 22.1 and 40.6, and 37.2 g/kg respectively. Milk fat concentration of C22:6 n-3 increased rapidly in cows receiving SCIM, reaching a maximum of 0.38 g/100 g FA by week 14. Similarly, blood concentration of C22:6 n-3 increased to 1.6 g/100 g FA by week 14 in cows fed SCIM. There was no effect of treatment on plasma metabolites, but plasma glucose was lower in cows fed SCIM compared to the Control at week 2, and higher in week 8. There was no effect of treatment on peak plasma PGFM concentration or area under the curve. It is concluded that feeding SCIM rapidly increases blood and milk concentrations of C22:6 n-3 which are maintained over time, but does not improve plasma PGFM in dairy cows.

Effect of dietary n-3 polyunsaturated rich fish oil supplementation on ovarian function and interferon stimulated genes in the repeat breeding cow

Dietary n-3 polyunsaturated fatty acids (n-3 PUFA) improve utero-ovarian functions and embryonic survival in postpartum dairy cows. Because early embryonic mortality is the major cause of repeat breeding (RB) in cows, there was investigation of the effect of dietary supplementation of n-3 PUFA [eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] rich fish oil (FO) from -2 to +2 weeks of artificial insemination on the size of preovulatory follicle (POF), serum progesterone (P₄) and relative abundance of the mRNA of interferon stimulated genes (ISG) that encode for these proteins in the peripheral blood leukocytes (PBL) in the RB cow (n = 12). The diet of control group was supplemented with palm oil (PO). The results indicated serum concentrations of EPA and DHA were greater by 4.6- and 3.5-fold, respectively at the end of feeding study in the RB cows of the FO group. The diameter of POF was larger by 2.2 mm in FO group; however, serum P₄ did not vary from day 14-20 post-artificial insemination. Greater abundance of ISG mRNA transcripts such as ISG15, RTP4, Mx2 and OAS1 in the PBL of pregnant cows of FO group indicates day 20 conceptuses produced more IFN-τ. It is concluded that supplementation of FO during the breeding period increased the size of POF and enhanced the abundance of ISG mRNA transcripts in RB cows that became pregnant.

Effect of n-3 PUFA-rich fish oil supplementation during late gestation on kidding, uterine involution and resumption of follicular activity in goat

We have shown that dietary supplementation of n-3 polyunsaturated fatty acid (n-3 PUFA)-rich fish oil (FO) around the breeding time improved the utero-ovarian functions in the goat. Here, we investigated the effect of FO supplementation during the periparturient period on serum n-3 PUFA, prostaglandin F_2α metabolite (PGFM), placental expulsion, uterine involution, resumption of oestrus and neonatal vigour. Rohilkhandi goat in advanced gestation (n = 16) was divided into two equal groups. One group was supplemented with FO containing 26% n-3 long-chain PUFA at the rate of 156 mg per kg body weight, while the control group was fed isocaloric palm oil (PO) from -3 to +3 week of kidding. Dietary FO increased serum concentration of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) by 7.3- and 6.6-fold, respectively, after 6 weeks of supplementation. Goats in FO group expelled the foetal membranes 99.1 min earlier (p < .01) than those of PO group. Further, dietary FO significantly decreased the serum PGFM on day 7 post-partum. However, no difference was found on uterine involution, which was complete by day 20 post-partum in either group. Resumption of follicular activity by day 5 post-partum was 87.5% in the FO as compared to 25% in the PO group (p < .05). Similarly, occurrence of behavioural oestrus by day 90 post-partum was 57.1% in goats of the FO group while none of does was in the PO group (p < .01) expressed oestrus. It was concluded that feeding FO-rich diet during -3 to +3 weeks of kidding decreased the PGFM till day 7 post-partum, hastened the expulsion of foetal membranes and reduced the time from kidding to first post-partum oestrus in Rohilkhandi does.

Folic acid and flaxseed oil supplements in Ossimi ewes: effect on body weight changes, progesterone profile, blood chemistry, and litter traits

The aim was to explore the impact of periconceptional folic acid or flaxseed oil (FXO) supplementation on fertility, progesterone profile, and blood chemistry in pregnant ewes during the breeding season. In total, 54 Ossimi ewes were divided into three groups (18 animals each). The control treatment (CON) fed a basal diet only, while the others fed the basal diet and supplemented every other day with a single bolus of folic acid (FO 500 μg/head) or flaxseed oil (FX 50 ml/head). During the early stage of pregnancy, the FO and FX groups showed significantly higher serum antioxidant activity (glutathione and superoxide dismutase) as compared with the control CON group (P = 0.012 and 0.007, respectively). Although no significant variations were detected in the serum nitric oxide levels during the early stage and mid-stage of pregnancy, the FO and FX groups showed significantly lower serum nitric oxide concentration in the late stage of pregnancy (P = 0.001). The FO and FX groups showed significantly higher serum progesterone concentrations during the early stage (10.9 and 11.4 ng/ml, respectively) and mid-stage (22.2 and 23.4 ng/ml, respectively) of pregnancy as compared with the CON group (7.72 and 13.9 ng/ml, respectively). The FX group exhibited a significantly higher lambing rate (P = 0.034), as well as the proportion of female lambs (P = 0.029) as compared with the CON group. In conclusion, supplementing Ossimi ewes with folic acid or FXO significantly improved the progesterone profile during pregnancy. Moreover, the FXO supplementation significantly increased the lambing rate and the female lamb rate as compared with the control group.

Does feeding extruded linseed to dairy cows improve reproductive performance in dairy herds? An observational study

Feeding n-3 fatty acids (FA) is often cited as a promising strategy to tackle impaired reproduction in dairy cows. However, the scientific literature shows conflicting results that may be explained by the nature of n-3 FA used, the amount supplemented and the timing of supplementation. In addition, designing a proper experimental design to study n-3 FA and reproduction is subjected to other difficulties such as the choice of the control diet or gaining enough statistical power. The objective of this retrospective observational study was to quantify the average effects of supplementing extruded linseed (EL), a feed rich in α-linolenic acid, to dairy cows on reproductive performances under field conditions in French commercial farms. Exposure measurement to EL feeding was particularly challenging as exact cow diets are not traced in farms. Therefore, to investigate the potential dose-effect relationship, we defined a proxy of EL intake per day by using deliveries of EL based feeds from 22 companies in the study period 2008-2015 in France. An artificial insemination (AI) was considered exposed only if the cow was supplemented with EL from the calving until 17 days after AI. Based on recommendations for EL use on the field, 4 exposures classes were created: [1-50] (n = 14,126 AIs), [50-300] (n = 88,261 AIs), [300-600] (n = 66,136 AIs), and [600-1500] (n = 28,287 AIs) g/cow/d. The reference population was composed of cows that did not receive any EL between calving until 17 days after AI within herds that were supplied, but not continuously during the study period (n = 226,795 AIs). Mean daily EL intake in exposed population was 337 g/cow/d (±239.4). Reproductive performance was studied on 423,605 AIs from 1096 herds and 158,125 cows using Cox models for days to first AI and days to conception, and logistic regression models for risk of return-to-service, adjusted for factors likely to influence the reproductive performance and for a herd random effect. Risk of return-to-service between 18 and 78 days after first and second AI did not differ between exposed and reference populations, Nevertheless, the effect on the days to first AI was higher with the lowest EL intake (HR: 1.14; 95% CI: 1.11, 1.17) than with higher EL intake levels (HR ranging from 1.06 to 1.07; 95% CI: 1.04, 1.09). Similarly, for the effect on the time from calving to conception from the lowest EL intake (HR: 1.19; 95% CI: 1.15, 1.23) compared to the higher EL intake levels (HR ranging from 1.08 to 1.11; 95% CI: 1.06, 1.14). This original large-scale epidemiological study provides new insights into the effects of feeding EL at a commercially sustainable level to dairy cows.

Effect of Dietary Fish Oil on Mammary Gland Development and Milk Production of Holstein Cow

The aim of this study was to evaluate the effect of feeding oil supplement on mammary gland development and milk production responses in Holstein cows. Ten multiparous Holstein cows (42.2±9.2 d before calving, 3.25±0.25 body condition score, and 620±35 kg body weight) were randomly assigned to treatments. Treatments were a diet with oil added as palm oil (PO; n=5), or fish oil (FO; n=5) given to cows until 63 d in milk. Milk yield was recorded daily, milk composition (fat, protein, lactose, total solid and somatic cell count) was measured weekly and fatty acid profiles of milk fat were determined at first and last week of the experiment. Samples of mammary tissue were obtained at 7 and 63 d in milk by biopsy gun. Tissue slides were analyzed by Image J software. Results showed that fish oil supplemented diet compared to the palm oil supplemented diet increased milk production after 6 weeks of lactation (P<0.05), content of polyunsaturated fatty acids milk fat (P<0.05) and docosahexaenoic acid (P<0.01). Moreover, n-6:n-3 ratio was decreased by fish oil supplement (P<0.05). Histological studies showed that FO increased the relative percentage of tissue area occupied by epithelial cells as well as a number of total alveoli in each microscopic field (P<0.05). Data suggested that feeding fish oil during the dry period and early lactation could improve development and function of the mammary gland in the dairy cow.

Effects of feeding a source of omega-3 fatty acid during the early postpartum period on the endocannabinoid system in the bovine endometrium

A total of sixteen Holstein dairy cows (35 ± 1.1 kg/d of milk yield) were randomly assigned to consider the effects of feeding omega-3 sources on endometrial endocannabinoids system (ECS) genes expression to understand the effect mechanism of omega-3 on reproductive performances during the early postpartum period to evaluate to what extent can be intervened in reproduction, e.g. via nutrition to improve fertility. Experimental diets were 1) either protected palm oil (control) or 2) extruded linseed (linseed). Cows (n = 16) were fed from calving date to 70 days in milk (DIM). There was no difference between groups (mean ± S.E.M.) in parity (3.0 ± 1.00) or body condition score (BCS) at calving day (3.1 ± 0.25). At 30 DIM, the ovulatory cycles of cows were synchronized using two injections of prostaglandin F2α (PGF2α) with a 14-day interval. On day 15 of synchronized estrous cycle (d0 = ovulation) uterine endometrial biopsies were collected to evaluate the expression of genes related to ECS (endocannabinoid receptor (CNR2), N-acyl phosphatidylethanolamine phospholipase D (NAPEPLD), fatty acid amide hydrolase (FAAH), N-acylethanolamine acid amidase (NAAA), monoglyceride lipase (MGLL)) and PGF2α. Results showed that dry matter intake and milk yield were not affected by diets. Uterine endometrial NAAA (7.69 fold), and MGLL (1.96 fold) genes expression were greater (P < 0.05) in cows fed linseed compared with control ones. The messenger RNA (mRNA) levels of CNR-2 (4.26 fold), and NAPEPLD (20.0 fold) were decreased (P < 0.05) in animals fed linseed compared to control cows. The expression of mRNA for the FAAH was not influenced by the diets. First service conception rate was greater in cows fed linseed compared to control cows (75 vs. 25%). Pregnancy loss within 32-60 day after artificial insemination (AI) was lower in cows fed linseed compared to control cows (0 vs. 100%). In conclusion these data demonstrated that positive effect of omega-3 on reproduction may act through a mechanism involving the ECS. However, more studies to be undertaken to confirm these results.

Embryonic development, luteal size and blood flow area, and concentrations of PGF2α metabolite in dairy cows fed a diet enriched in polysaturated or polyunsaturated fatty acid

The objective of this study was to examine effects of sunflower (SO) and palm oil (PO) supplements in the diet on embryonic development, luteal size and blood flow area, PGF2α metabolite (PGFM), and progesterone (P4) concentrations. Prepartum cows (n = 42) were randomly assigned to one of three dietary treatments (control, 4% PO, and 4% SO supplements). Animals were fed diets individually from day 28 prepartum to day 111 postpartum. Luteal size and blood flow area were determined throughout the estrous cycle by Doppler ultrasonography. Oocytes were collected in three ovum pick-up sessions at 2 week intervals for the in vitro embryo production. Oocyte characteristics and embryonic development were not affected by dietary treatments. Cows fed 4% SO had a greater (P < 0.05) concentration of PGFM from day 15 to day 35 postpartum than those cows fed 4% PO and the control group. On day 11 of the estrous cycle (mid-luteal phase), serum P4 concentrations (6.0 ± 0.7, 5.7 ± 0.5, and 4.7 ± 0.6 ng/ml), luteal size (7.0 ± 0.2, 6.5 ± 0.2, and 5.3 ± 0.1 cm2) and luteal blood flow area (1.3 ± 0.2, 1.2 ± 0.1, and 0.9 ± 0.1 cm2) were greater (P < 0.05) in cows fed 4% SO and 4% PO than the control group, respectively. Thus, plant oil supplements in diets affected luteal size and serum P4 and PGFM concentrations, but not early embryonic development. Such changes in secretion of PGF2α and P4 indicate that plant oil supplements during pre- and postpartum may alter uterine and luteal functions.

Docosahexaenoic acid (DHA) effects on proliferation and steroidogenesis of bovine granulosa cells

BACKGROUND

Docosahexaenoic acid (DHA) is a n-3 polyunsaturated fatty acid (PUFA) belonging to a family of biologically active fatty acids (FA), which are known to have numerous health benefits. N-3 PUFAs affect reproduction in cattle, and notably directly affect follicular cells. In terms of reproduction in cattle, n-3 PUFA-enriched diets lead to increased follicle size or numbers.

METHODS

The objective of the present study was to analyze the effects of DHA (1, 10, 20 and 50 μM) on proliferation and steroidogenesis (parametric and/or non parametric (permutational) ANOVA) of bovine granulosa cells in vitro and mechanisms of action through protein expression (Kruskal-Wallis) and signaling pathways (non parametric ANOVA) and to investigate whether DHA could exert part of its action through the free fatty acid receptor 4 (FFAR4).

RESULTS

DHA (10 and 50 μM) increased granulosa cell proliferation and DHA 10 μM led to a corresponding increase in proliferating cell nuclear antigen (PCNA) expression level. DHA also increased progesterone secretion at 1, 20 and 50 μM, and estradiol secretion at 1, 10 and 20 μM. Consistent increases in protein levels were also reported for the steroidogenic enzymes, cytochrome P450 family 11 subfamily A member 1 (CYP11A1) and hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 1 (HSD3B1), and of the cholesterol transporter steroidogenic acute regulatory protein (StAR), which are necessary for production of progesterone or androstenedione. FFAR4 was expressed in all cellular types of bovine ovarian follicles, and in granulosa cells it was localized close to the cellular membrane. TUG-891 treatment (1 and 50 μM), a FFAR4 agonist, increased granulosa cell proliferation and MAPK14 phosphorylation in a similar way to that observed with DHA treatment. However, TUG-891 treatment (1, 10 and 50 μM) showed no effect on progesterone or estradiol secretion.

CONCLUSIONS

These data show that DHA stimulated proliferation and steroidogenesis of bovine granulosa cells and led to MAPK14 phosphorylation. FFAR4 involvement in DHA effects requires further investigation, even if our data might suggest FFAR4 role in DHA effects on granulosa cell proliferation. Other mechanisms of DHA action should be investigated as the steroidogenic effects seemed to be independent of FFAR4 activation.

Oleic acid in the modulation of oocyte and preimplantation embryo development

Potential reproductive effects are considered as the major aspect of biomolecules functionality in an organism. The recent identification of differential patterns of fatty acids across ovarian follicles and their association with levels of sexual maturity highlights the importance of these biomolecules. It is well known that fatty acids are highly diverse in terms of their functional properties. Oleic acid is chemically classified as an unsaturated omega-9 fatty acid. Besides serving as an important energy source, oleic acid is involved in metabolic and structural roles. Free and esterified oleic acids are compartmentalized into discrete extracellular fluids, cell organelles and found within the cytosol. This review summarizes the current knowledge on the contribution of oleic acid in regulating female fertility, particularly its involvement in female germ cell growth and development. Oleic acid has been identified as a blastomeric and post-cryopreservation survival biomarker in bovine. Several related studies have shown the critical role of oleic acid in counteracting the detrimental effects of saturated fatty acids and in paracrine support of oocyte development. Although available data are not ideally detailed, most data suggest that oleic acid can contribute to normal oocyte and preimplantation embryo development via mechanisms involving metabolic partitioning of fatty acids, change in the membrane structural organization, attenuation of oxidative stress and regulation of intracellular signalling. Thus, oleic acid may play a significant role in oocyte and early embryo development, suggesting that future studies should explore in more detail its potential effects on the physiopathology of female reproduction.

Docosahexaenoic acid mechanisms of action on the bovine oocyte-cumulus complex

Background

Supplementation of bovine oocyte-cumulus complexes during in vitro maturation (IVM) with 1 μM of docosahexaenoic acid (DHA), C22:6 n-3 polyunsaturated fatty acid, was reported to improve in vitro embryo development. The objective of this paper was to decipher the mechanisms of DHA action.

Results

Transcriptomic analysis of 1 μM DHA-treated and control cumulus cells after 4 h IVM showed no significant difference in gene expression. MALDI-TOF mass spectrometry analysis of lipid profiles in DHA-treated and control oocytes and cumulus cells after IVM showed variations of only 3 out of 700 molecular species in oocytes and 7 out of 698 species in cumulus cells (p < 0.01).

We showed expression of free fatty acid receptor FFAR4 in both oocytes and cumulus cells, this receptor is known to be activated by binding to DHA. FFAR4 protein was localized close to the cellular membrane by immunofluorescence. Functional studies demonstrated that supplementation with FFAR4 agonist TUG-891 (1 μM or 5 μM) during IVM led to an increased blastocyst rate (39.5% ± 4.1%, 41.3% ± 4.1%), similar to DHA 1 μM treatment (39.2% ± 4.1%) as compared to control (25.2% ± 3.6%).

FFAR4 activation via TUG-891 led to beneficial effect on oocyte developmental competence and might explain in part similar effects of DHA.

Conclusions

In conclusion, we suggested that low dose of DHA (1 μM) during IVM might activate regulatory mechanisms without evident effect on gene expression and lipid content in oocyte-cumulus complexes, likely through signaling pathways which need to be elucidated in further studies.

Electronic supplementary material

The online version of this article (10.1186/s13048-017-0370-z) contains supplementary material, which is available to authorized users.

The effect of dha omega-3 feeding in the high yielding holstein herd

The aim of this study was to analyse the effect of supplementary feeding of DHA (Docosahexaenoic Acid) rich algae product (Algae STM Alltech Inc.) on production of milk, fat and protein as well as on reproduction of high yielding Holstein dairy herd. Field trial was set up on Top 10 dairy farm in western part of Slovakia, under commercial conditions. The data of high yielding dairy cows, separated in two groups of 30 (control) and 29 (trial) animals, were recorded for period of 3 subsequent months from October to December 2015. Animals were fed once a day Total Mixed Ration based diet with different feed mixture composition in trial group (+100 g Algae STM Alltech Inc. per cow and day). Performance data were collected in accordance with official milk recording system of Breeding Services of Slovak Republic s. e. and milk samples were collected once per month according to the A4 standard methodology. The control group showed higher level of milk production compared to trial. Our study indicated that the feeding of algae caused milk fat depression and generally lower protein content in milk. Significant impact of algae feeding was found also for the level of urea in milk. In addition, the supplementary feeding of DHA may represent effective strategy to increase the percentage of pregnancies per inseminations in lactating dairy cows.

Comparison between conjugated linoleic acid and essential fatty acids in preventing oxidative stress in bovine mammary epithelial cells

Some in vitro and in vivo studies have demonstrated protective effects of conjugated linoleic acid (CLA) isomers against oxidative stress and lipid peroxidation. However, only a few and conflicting studies have been conducted showing the antioxidant potential of essential fatty acids. The objectives of the study were to compare the effects of CLA to other essential fatty acids on the thiol redox status of bovine mammary epithelia cells (BME-UV1) and their protective role against oxidative damage on the mammary gland by an in vitro study. The BME-UV1 cells were treated with complete medium containing 50 μM of cis-9,trans-11 CLA, trans-10,cis-12 CLA, α-linolenic acid, γ-linolenic acid, and linoleic acid. To assess the cellular antioxidant response, glutathione, NADPH, and γ-glutamyl-cysteine ligase activity were measured 48 h after addition of fatty acids (FA). Intracellular reactive oxygen species and malondialdehyde production were also assessed in cells supplemented with FA. Reactive oxygen species production after 3 h of H₂O₂ exposure was assessed to evaluate and to compare the potential protection of different FA against H₂O₂-induced oxidative stress. All FA treatments induced an intracellular GSH increase, matched by high concentrations of NADPH and an increase of γ-glutamyl-cysteine ligase activity. Cells supplemented with FA showed a reduction in intracellular malondialdehyde levels. In particular, CLA isomers and linoleic acid supplementation showed a better antioxidant cellular response against oxidative damage induced by H₂O₂ compared with other FA.

Effects of Dietary Supplementation with Different Polyunsaturated Fatty Acids on Expression of Genes Related to Somatotropic Axis Function in the Liver, Selected Blood Indicators, Milk Yield and Milk Fatty Acids Profile in Dairy Cows

The objective of this study was to investigate whether dietary supplementation with different polyunsaturated fatty acids (PUFA s) affects expression of genes related to somatotropic axis and the plasma concentrations of insulin, glucose, non-esterified fatty acids (NEFA), beta hydroxyl butyrate acids (BHBA) and insulin-like growth factor 1 (IGF1) and milk fatty acids profile. Right after calving, Holstein cows (n=45) were randomly assigned to one of three diets supplemented with roasted whole soybean as a source of omega-6 PUFA (omega-6, n=15), linseed as a source of omega-3 PUFA (omega-3, n=15) or palm oil (control, n=15). Each cow was in the study over a period of 70 days. Blood samples were collected every two weeks from day 1 to 70 of lactation and plasma concentrations of insulin, glucose, NEFA, BHBA and IGF1 were determined. Liver samples were taken from a subset of 18 cows (6 per diet) at day 70 postpartum and hepatic mRNA level of total growth hormone-receptor 1A (GHR1A), insulin receptor (INSR), IGF1 and insulinlike growth factor binding protein (IGFBP2) was assessed. Experimental diets did not affect milk yield. Plasma glucose and insulin concentrations were greater for omega-3 treatment compared to omega-6 and control treatments. Cows fed diets enriched in omega-3 exhibited greater INSR and GHR1A mRNA expression, and a tendency for greater IGF1 mRNA expression in the liver compared to omega-6 and control cows. Plasma IGF1 concentration was significantly higher in omega-3 treatment compared with omega-6 and control treatments. Results of this study suggest that feeding omega-3 PUFA s during early postpartum couples with the somatotropic axis, leading to an increase in plasma IGF1 concentration in dairy cows.

N-3 polyunsaturated fatty acid DHA during IVM affected oocyte developmental competence in cattle

The positive effect of n-3 polyunsaturated fatty acids (FAs) on fertility in ruminants seems to be partly mediated through direct effects on the oocyte developmental potential. We aimed to investigate whether supplementation with physiological levels of docosahexaenoic acid (DHA, C22:6 n-3 polyunsaturated fatty acids) during IVM has an effect on oocyte maturation and in vitro embryo development in cattle. We reported that DHA (0, 1, 10, or 100 μM) had no effect on oocyte viability or maturation rate after 22-hour IVM. Incubation of oocyte-cumulus complexes with 1-μM DHA during IVM significantly increased (P < 0.05) oocyte cleavage rate as compared with control (86.1% vs. 78.8%, respectively) and the greater than 4-cell embryo rate at Day 2 after parthenogenetic activation (39.1% vs. 29.7%, respectively). Supplementation with 1 μM DHA during IVM also induced a significant increase in the blastocyst rate at Day 7 after IVF as compared with control (30.6% vs. 17.6%, respectively) and tended to increase the number of cells in the blastocysts (97.1 ± 4.9 vs. 81.2 ± 5.3, respectively; P = 0.08). On the contrary, 10-μM DHA had no effects, whereas 100-μM DHA significantly decreased the cleavage rate compared with control (69.5% vs.78.8%, respectively) and the greater than 4-cell embryo rate at Day 2 after parthenogenetic activation (19.5% vs. 29.7%). As was shown by real-time polymerase chain reaction, negative effects of 100-μM DHA were associated with significant increase of progesterone synthesis by oocyte-cumulus complexes, a three-fold increase in expression level of FA transporter CD36 and a two-fold decrease of FA synthase FASN genes in cumulus cells (CCs) of corresponding oocytes. Docosahexaenoic acid at 1 and 10 μM had no effect on expression of those and other key lipid metabolism-related genes in CC. In conclusion, administration of a low physiological dose of DHA (1 μM) during IVM may have beneficial effects on oocyte developmental competence in vitro without affecting lipid metabolism gene expression in surrounding CCs, contrarily to 100 μM DHA which diminished oocyte quality associated with perturbation of lipid and steroid metabolism in CC.

Effect of linseed feeding on blood metabolites, incidence of cystic follicles, and productive and reproductive performance in fresh Holstein dairy cows

This study was done to investigate the effect of feeding linseed on blood metabolites, incidence of cystic follicles, resumption of postpartum ovarian cyclicity, pregnancy rate, milk production, and composition in fresh Holstein dairy cows. A total of 399 dairy cows were assigned randomly to 2 diets. Diets contained either protected palm oil (CON) or extruded linseed (LIN) and were fed from calving to d 40 postpartum. Ovaries of each cow were examined on d 10, 20, 30, and 40 after parturition (parturition=d 0) by transrectal ultrasonography to determine follicular development, ovarian disorders, and cyclicity. Blood samples were collected at 14-d intervals for 6 wk starting on the day of parturition to determine plasma concentrations of glucose, β-hydroxybutyrate (BHBA), nonesterified fatty acids (NEFA), and blood urea N (BUN). Results showed plasma glucose concentration was affected by the diets and was greater in the LIN treatment, but BHBA, NEFA, and BUN concentrations were similar among treatments. Dietary treatments had no significant effect on milk production and composition except milk fat percentage that significantly decreased in cows fed LIN (3.55%) compared with those fed with CON (4.17%). Plasma progesterone concentrations were greater in LIN treatment than CON treatment (1.31±0.09 vs. 0.87±0.09) at early postpartum. The resumption of cyclicity and onset of estrus were influenced by treatments and reduced by 7 d in LIN treatment compared with CON treatment. Cows fed diets enriched in LIN fatty acids had a lesser incidence of cystic follicles. Treatments did not differ significantly in terms of the number of days open, number of services per pregnancy, and pregnancy rate. In conclusion, feeding linseed immediately after parturition decreased milk fat and incidence of cystic follicles, increased progesterone concentrations early postpartum, and caused earlier resumption of cyclicity but did not affect pregnancy rate.

Effects of linseed oil or whole linseed supplementation on performance and milk Fatty Acid composition of lactating dairy cows

The objective of this study was to determine the effects of linseed oil or whole linseed supplementation on performance and milk fatty acid composition of lactating dairy cows. Thirty six Holstein Friesian crossbred lactating dairy cows were blocked by milking days first and then stratified random balanced for milk yields and body weight into three groups of 12 cows each. The treatments consisted of basal ration (53:47; forage:concentrate ratio, on a dry matter [DM] basis, respectively) supplemented with 300 g/d of palm oil as a positive control diet (PO), or supplemented with 300 g/d of linseed oil (LSO), or supplemented with 688 g/d of top-dressed whole linseed (WLS). All cows were received ad libitum grass silage and individually fed according to the treatments. The experiment lasted for 10 weeks including the first 2 weeks as the adjustment period, followed by 8 weeks of measurement period. The results showed that LSO and WLS supplementation had no effects on total dry matter intake, milk yield, milk composition, and live weight change; however, the animals fed WLS had higher crude protein (CP) intake than those fed PO and LSO (p<0.05). To compare with the control diet, dairy cow’s diets supplemented with LSO and WLS significantly increased milk concentrations of cis-9, trans-11-conjugated linoleic acid (CLA) (p<0.05) and n-3 fatty acids (FA) (p<0.01), particularly, cis-9,12,15-C18:3, C20:5n-3 and C22:6n-3. Supplementing LSO and WLS induced a reduction of medium chain FA, especially, C12:0-C16:0 FA (p<0.05) while increasing the concentration of milk unsaturated fatty acids (UFA) (p<0.05). Milk FA proportions of n-3 FA remarkably increased whereas the ratio of n-6 to n-3 decreased in the cows supplemented with WLS as compared with those fed the control diet and LSO (p<0.01). In conclusion, supplementing dairy cows’ diet based on grass silage with WLS had no effect on milk yield and milk composition; however, trans-9- C18:1, cis-9, trans-11-CLA, n-3 FA and UFA were increased while saturated FA were decreased by WLS supplementation. Therefore, it is recommended that the addition 300 g/d of oil from whole linseed should be used to lactating dairy cows’ diets.