Milk Fatty Acid Content Research Articles

ACAA2 and FASN polymorphisms affect the fatty acid profile of Chios sheep milk.

The objective of the research reported in this research communication was the identification and association of single nucleotide polymorphisms (SNP) in the ovine DGAT1, FASN, SCD1 and ACAA2 genes with milk fat percentage and fatty acid (FA) content. Three consecutive monthly milk samplings were obtained from a total of 429 purebred Chios ewes during mid-lactation. Genotypic data were jointly analyzed with 1184 fat content and 37 718 FA percentage records using mixed models. The 3' untranslated region (UTR) of the DGAT1 gene and the 5' and 3'UTRs of the SCD1 gene appeared to be monomorphic. The FASN g.14777C>T SNP on exon 31 was associated with C13:0 and the ACAA2 g.2982T>C SNP on the 3'UTR was associated with C9:0, C11:0, C12:1 cis-9, C13:0 and the ω6/ω3 index, while fat percentage was not affected by the identified SNPs. The results could be useful for breeding programs aiming to improve the quality and nutritional value of ovine milk.

Impact of Extended Lactation on Fatty Acid Profile and Milk Composition of Dual Purpose Tropical Goat.

Extended lactation has been implemented to increase milk yield in limited case. There is need further investigation in term of milk composition, fatty acid profile and milk flavour as recommendation for further implementation. The study lasted from July-September, 2017, used thirty lactating Etawah Crossbred goats in small farms of Sleman, Yogyakarta. Samples were collected from normal period and extended lactation which lasted for 2-3 months and longer than 10 months, respectively. The data on milk yield, composition, physical quality, fatty acids profile, sensory properties and nutrient consumption were measured on samples of 14 consecutive days. Assessments were done in Faculty of Animal Science and Integrated Research Laboratory, Universitas Gadjah Mada. Statistical analysis used ANOVA and Kruskal Wallis test and were processed with SPSS programme version 16. Extended lactation did not affect milk yield and nutrient consumption of goat but caused higher content of milk fat, protein, total solid, acidity, caprylic, capric and total short-chain fatty acids in compared with normal lactation (p<0.05). The average values were 5.33, 4.40, 15.85, 0.30, 1.99, 9.10 and 12.13% vs. 3.75, 3.64, 13.55, 0.26, 1.69, 7.09 and 9.76% of total fatty acids in milk, respectively. Fatty acid profile did not associate with milk flavour. Composition, acidity and short chain fatty acids content in milk of extended lactation were higher than in normal period but did not change milk flavour.

Relationships between trans-10 shift indicators and milk fat traits in dairy ewes: Insights into milk fat depression

The causative relationship between ruminal biohydrogenation alterations known as the trans-10 shift and marine lipid-induced milk fat depression (MFD) has been questioned in dairy ewes, but the large intra- and inter-experiment differences in the levels of trans-10 shift indicators precludes firm conclusions. This meta-analysis was conducted to quantify the relationship between trans-10 shift milk indicators [i.e., trans-10,cis-12 conjugated linoleic acid (CLA), trans-10 18:1 or trans-10:trans-11 18:1 ratio] and lactation performance, mainly milk fat traits, in Assaf dairy ewes. A database comprising of 17 experiments including 50 dietary treatments was compiled. The diets were grouped into 2 dietary conditions: (1) non-MFD condition, which included 14 diets supplemented with plant oils and tannins that modified the milk fatty acid profile without lowering milk fat concentration and yield, and 12 respective control diets, and (2) MFD condition, which included 15 diets supplemented with marine lipids that induced the low fat-milk syndrome, and 9 respective control diets. The overall levels of milk trans-10 shift indicators did not differ between dietary conditions, but significant increments were found in the supplemented diets relative to their respective controls. A similar linear and negative (slope: −7.28 ± 2.816) relationship between milk fat concentration and trans-10,cis-12 CLA was found in both dietary conditions. However, the quadratic negative response of milk fat content to trans-10 18:1 concentration was greater in MFD than in non-MFD conditions. In the two dietary conditions, the relationship between milk trans-10,cis-12 CLA or trans-10 18:1 and de novo fatty acid concentration in milk was negative, whereas the relationship with preformed fatty acid proportion was positive. The magnitude of changes in both milk fatty acid groups in response to changes in these trans-10 shift indicators were greater in non-MFD compared with MFD conditions. Milk fat yield and trans-10 shift indicators were only negatively related in ewes that were fed marine lipid supplements, because reductions in de novo fatty acid yield with increased shift indicator levels were not counteracted by concomitant increments in preformed fatty acid secretion. The best-fit (lower root mean squared error, higher R2 and no prediction biases) equations of milk fat or major milk fatty acid groups, as concentration or yield, were based on milk trans-10 18:1 concentration. In conclusion, different responses between the two conditions to similar shift indicator levels support that the trans-10 shift would not be a major factor explaining the diet-induced low-fat milk syndrome in dairy ewes.

Milk fatty acid composition, rumen microbial population and animal performance in response to diets rich in linoleic acid supplemented with

Context Rumen biohydrogenation is an important way to produce conjugated linoleic acid (CLA), especially the rumenic acid isomer. However, CLA is principally synthesised endogenously in lactating mammals by delta 9-desaturase in breast tissue. Aims The aim of the study was to evaluate milk fatty acid profile, rumen microbial population and animal performance in response to diets containing sunflower oil either supplemented with or without flavonoids and essential oils from Piper betle L. powder (PP) in dairy goats. Method Twelve multiparous Saanen goats (42 ± 1.00 kg; mean ± s.d.) were randomly assigned to two treatment groups in an experiment that lasted for 6 weeks. The two experimental diets formulated as total mixed ration were: control (CTH) diet (containing 0% PP) and DPB diet (CTH diet containing 1.3% PP on a dry-matter basis). Key results Inclusion of flavonoids and essential oils from PP in the diet (DPB) did not affect dry-matter intake but resulted in a greater milk yield and altered the composition of milk. Compared with the control diet (CTH), the DPB diet decreased the saturated fatty acid concentration and increased the unsaturated fatty acid concentration in milk. Inclusion of PP decreased the C18:0 production (P &lt; 0.05), resulting in higher C18:1 trans11 and C18:2 cis9 trans11 (P &lt; 0.05) concentrations. Overall, DPB diet increased the total CLA by 1.5-fold, from 1.77 to 2.62 g/100 g fatty acid. The desaturase rate (except desaturase for carbon 18, P &lt; 0.05), and atherogenic and thrombogenic indices were not affected by inclusion of PP in the DPB diet. Moreover, the DPB diet escalated total volatile fatty acid production and altered the volatile fatty acid profile. Compared with goats fed with CTH diet, PP supplementation increased the presence of ruminal Butyrivibrio fibrisolvens by ~5-fold, but the presence of B. proteoclasticus decreased to about 1/11 of the control. Conclusions The use of sunflower oil at 17.6 g/kg diet and inclusion of a practical dose of flavonoids and essential oils from Piper betle L. leaves in the diet of dairy goats can be an efficient method to improve milk yield and milk composition, including increasing the CLA concentration of milk. Implications These results constitute an alternative strategy to improve milk quality, without negatively affecting animal performance.

Impact of Royal Jelly Supplement on Ewe&amp;apos;s Milk Fat Content and Fatty Acid Profile During the Early Stage of Lactation

The aim was to study the possible effects of royal jelly (RJ) supplementation on milk fat content and fatty acids (FA) profile of ewes during the early stage of lactation. Randomly, thirty-six Ossimi ewes were divided into two groups (18 animals each). The first group was offered the basal diet which was considered as a control group, whereas the second group was fed the basal diet, in addition to a supplement of a single bolus of RJ (1000 mg/head) every two days as a treated group. Regardless the effect of time, the RJ-supplemented group recorded a non-significant increase in daily milk yield (1.22 kg) when compared with the control (1.08 kg) group (P<0.063). While, the RJ-supplemented ewes showed significantly increase in milk fat percentage (P<0.008) as compared to control group. Lactating ewes in the control group produced significantly higher contents of milk C14:0 (P<0.036) and C18:0 (P<0.027) saturated FA than that in the RJ group. However, the contents of milk C6:0 and C17:0 in the RJ group were significantly greater than that estimated in the control (P<0.050 and 0.041, respectively). Furthermore, Lactating ewes supplemented with RJ produced significantly higher contents of milk C16:1 (P<0.001), C18:1 (P<0.001) and C18:2 (P<0.046) unsaturated FA than the control group. It can be concluded that supplementation of ewes during the early stage of lactation with RJ can improve the nutritive value of milk fat, and appears to be an opportunity to modify the concentrations of certain milk fatty acids.

Faba bean-rapeseed silage as substitute for Italian ryegrass silage: effects on performance and milk quality of grazing dairy cows

Three trials were conducted to study the effect of including in the ration of dairy cows the intercrop faba bean-rapeseed or Italian ryegrass silages on feed intake, milk quality and enteric methane emissions. Ten lactating Holstein cows, randomly allocated in two groups, were used in each trial in a crossover design. Dry matter intake and milk yield were recorded daily for each data period. Milk was sampled for analyses three times per period. Enteric methane emission was estimated applying a model that includes bodyweight, dry matter intake, nutritional values of feeds and milk composition. Concentrate and grass intake did not differ between treatments, while total mixed ration intake was higher with Italian ryegrass silage. Milk yield and protein concentration also increased with the Italian ryegrass treatment. The milk urea concentration was higher with the faba bean and rapeseed diet. Fatty acid profiles were affected by feeding strategy. Thereby, t11 18:1, c9 18:1 and total unsaturated fatty acid were higher when the intercrop silage was fed. As consequence, atherogenicity index and thrombogenicity index were lower under that treatment. Estimated enteric methane emissions did not differ between treatments. In conclusion, faba bean-rapeseed intercrop can be an alternative to Italian ryegrass to feed dairy cows. The rations formulated with the intercrop silage have potential to improve the milk fatty acid content, and show healthier profiles for consumers. However, it would be useful to study the protein content of these crops to avoid possible excess urea in milk and to maintain sustainable milk yield and milk protein content.

Characteristics of bifidobacterial conjugated fatty acid and hydroxy fatty acid production and its potential application in fermented milk

This is the first study to elucidate bifidobacterial conjugated fatty acid and hydroxy fatty acid production as well as its potential in fermented milk. One hundred and fifty-two bifidobacteria belonging to seven species were assayed in this study. The results showed that only Bifidobacterium breve (B. breve), Bifidobacterium longum (B. longum), Bifidobacterium pesudocatenulatum (B. pseudocatenulatum) and Bifidobacterium dentium (B. dentium) generated CLA and CLNA, while nearly all the strains could convert free LA into 10-HOE. B. breve showed the highest CLA- and CLNA-generation ability (the highest conversion rate, 90.1%, for B. breve CCFM683), while B. pseudocatenulatum revealed higher 10-HOE-producing ability. Further study demonstrated that 10-HOE competition could influence the CLA generation in Bifidobacterium. Furthermore, B. breve CCFM683, as the highest CLA- and CLNA-producer, could increase the content of CLA and CLNA to 0.14 mg/mL and 0.065 mg/mL in fermented milk, presenting as a potentially ideal starter culture increasing conjugated fatty acid contents in milk.

Effects of different feeding regimens on milk fatty acid composition and milk flavor from the perspective of regional resource utilization

AbstractFeed is a primary factor affecting different milk components and creating a specific milk flavor. Dairy farms in different regions often depend on different feed resources and feeding regimens. This study aimed to evaluate the effect of completely different feeding regimens on the milk fatty acid (FA) profile and milk flavor. Eight lactating Holstein cows were assigned to one of two distinct feeding regimens, one grass silage‐based diet (GS) and one by‐product‐based diet (BP), using a switchback design with three periods of 28 days each. A sensory test of the pasteurized milk was conducted using the paired preference method. Dry matter, crude protein and total digestible energy intake were similar between the groups. There was also no difference in daily milk yields, milk fat, protein, lactose and solids‐not‐fat contents between the groups. Milk FA content with chain lengths C12–C14:1, C16 and C16:1cis and the saturated fatty acid (SFA) content were significantly higher in the GS group than in the BP group. In contrast, the milk FA content with chain lengths C18 and C18:1cis–C18:2 and the unsaturated fatty acid (UFA) content, including mono‐UFA (MUFA) and poly‐UFA (PUFA), were significantly higher in the BP group than in the GS group. The different feeding regimens did not affect milk sensory properties, including aroma, palatability, aftertaste, texture, body and sweetness. Using food by‐products that contain relatively high levels of PUFAs resulted in PUFA‐rich milk. However, even if using a distinct feeding regimen based on conserved or by‐product feeds, it may be difficult to create characteristic milk with an original flavor that is clearly identified by consumers.

Genetic and phenotypic trends for milk fatty acids in a Holstein cattle population reared under tropical conditions

Evaluation of genetic and phenotypic trends is important to monitor the evolution of dairy cattle breeding programs. Traits that are not commonly included as selection goals should also be monitored, especially when they have some effect on consumer health, such as milk fatty acids profile. Thus, the aim was to evaluate the genetic and phenotypic trends of the milk fatty acids composition on a Holstein dairy cattle population, from three farms, reared in a tropical environment. Monthly records of palmitic (C16:0), stearic (C18:0), oleic (C18:1), total saturated (SFA), unsaturated (UFA), monounsaturated (MUFA), and polyunsaturated (PUFA) fatty acids content in milk (g/100 g of milk), were collected of 2047 Holstein cows from three Brazilian farms between May and December of 2012. The pedigree file contained 7963 animals of seven generations. Genetic and phenotypic trends were obtained by linear regression of breeding values or phenotypic values, respectively, over generations. Single-trait analyses were performed and the breeding values were estimated using Bayesian approach. All traits showed negative phenotype trend (−0.02723 g/100 g of milk to −0.00395 g/100 g of milk), indicating reduction of the phenotypic value over generations. According to the genetic trends for MUFA and PUFA (−0.00023 and −0.00005, respectively, in g/100 g of milk) the breeding values of the animals were reduced throughout the generations, while for SFA, C16:0 and C18:0 the genetic trends (0.00134, 0.00052 and 0.00013, respectively, in g/100 g of milk) showed an increase in breeding values, possibly due to correlated effects originated from selection protocols applied to the herd. The linear regression coefficients of the genetic values in the generations were not significant for UFA and C18:1 (p-value > 0.6226 and p-value > 0.9708, respectively). Significant genetic and phenotypic trends of small magnitude were obtained, which may be a consequence of the absence of direct selection for these traits in these populations. Genetic and phenotypic gains for fatty acids profile in milk should be monitored to guide breeding programs in their selection objectives. It is suggested to investigate the causes of possible correlated response in the studied populations.

PSV-16 Effects of dietary coated omega-3 supplementation on growth performance, nutrient digestibility, blood profiles, and fatty acid composition in lactating sows and suckling piglets

Abstract Improving sow nutrition is one approach that could produce such potential increases. Polyunsaturated fatty acids (PUFAs) are critical nutrients that play an important role in maintaining animal health with better physiological condition. This study was conducted to determine the effects of dietary coated omega-3 supplementation on growth performance, nutrient digestibility, blood profiles, and fatty acid composition in lactating sows and suckling piglets. A total of 16 lactating sows (Landrace × Yorkshire) and their litters were used in a 26-day experiment. Sows were randomly allotted into two groups: (i) CON (Basal diet); (ii) TRT1 (Basal diet + 0.50% omega-3). In the current study, the supplementation of coated omega-3 increased piglet’s body weight (day 7) (P = 0.045) and average daily gain (day 0 to day 7) (P = 0.006) significantly compared with control. There was a significant effect (P = 0.048) on the blood fatty acid contents of sows fed coated omega-3 FA at weaning. In addition, the milk fatty acid contents (C16, C17 and C18) from sows fed diet supplemented with coated omega-3 FA were higher than those fed control diet on day 16. In conclusion, omega-3 diets improved BW and ADG of suckling piglets during the first week. It also improved the fatty acid content of blood and milk in lactating sows.

The Concentration of Omega-3 Fatty Acids in Human Milk Is Related to Their Habitual but Not Current Intake.

This study determined fatty acid (FA) concentrations in maternal milk and investigated the association between omega-3 fatty acid levels and their maternal current dietary intake (based on three-day dietary records) and habitual dietary intake (based on intake frequency of food products). Tested material comprised 32 samples of human milk, coming from exclusively breastfeeding women during their first month of lactation. Milk fatty acids were analyzed as fatty acid methyl ester (FAME) by gas chromatography using a Hewlett-Packard 6890 gas chromatograph with MS detector 5972A. We did not observe any correlation between current dietary intake of omega-3 FAs and their concentrations in human milk. However, we observed that the habitual intake of fatty fish affected omega-3 FA concentrations in human milk. Kendall’s rank correlation coefficients were 0.25 (p = 0.049) for DHA, 0.27 (p = 0.03) for EPA, and 0.28 (p = 0.02) for ALA. Beef consumption was negatively correlated with DHA concentrations in human milk (r = −0.25; p = 0.046). These findings suggest that current omega-3 FA intake does not translate directly into their concentration in human milk. On the contrary, their habitual intake seems to markedly influence their milk concentration.

Body and milk traits as indicators of dairy cow energy status in early lactation

The inclusion of feed intake and efficiency traits in dairy cow breeding goals can lead to increased risk of metabolic stress. An easy and inexpensive way to monitor postpartum energy status (ES) of cows is therefore needed. Cows' ES can be estimated by calculating the energy balance from energy intake and output and predicted by indicator traits such as change in body weight (ΔBW), change in body condition score (ΔBCS), milk fat:protein ratio (FPR), or milk fatty acid (FA) composition. In this study, we used blood plasma nonesterified fatty acids (NEFA) concentration as a biomarker for ES. We determined associations between NEFA concentration and ES indicators and evaluated the usefulness of body and milk traits alone, or together, in predicting ES of the cow. Data were collected from 2 research herds during 2013 to 2016 and included 137 Nordic Red dairy cows, all of which had a first lactation and 59 of which also had a second lactation. The data included daily body weight, milk yield, and feed intake and monthly BCS. Plasma samples for NEFA were collected twice in lactation wk 2 and 3 and once in wk 20. Milk samples for analysis of fat, protein, lactose, and FA concentrations were taken on the blood sampling days. Plasma NEFA concentration was higher in lactation wk 2 and 3 than in wk 20 (0.56 ± 0.30, 0.43 ± 0.22, and 0.13 ± 0.06 mmol/L, respectively; all means ± standard deviation). Among individual indicators, C18:1 cis-9 and the sum of C18:1 in milk had the highest correlations (r = 0.73) with NEFA. Seven multiple linear regression models for NEFA prediction were developed using stepwise selection. Of the models that included milk traits (other than milk FA) as well as body traits, the best fit was achieved by a model with milk yield, FPR, ΔBW, ΔBCS, FPR × ΔBW, and days in milk. The model resulted in a cross-validation coefficient of determination (R2cv) of 0.51 and a root mean squared error (RMSE) of 0.196 mmol/L. When only milk FA concentrations were considered in the model, NEFA prediction was more accurate using measurements from evening milk than from morning milk (R2cv = 0.61 vs. 0.53). The best model with milk traits contained FPR, C10:0, C14:0, C18:1 cis-9, C18:1 cis-9 × C14:0, and days in milk (R2cv = 0.62; RMSE = 0.177 mmol/L). The most advanced model using both milk and body traits gave a slightly better fit than the model with only milk traits (R2cv = 0.63; RMSE = 0.176 mmol/L). Our findings indicate that ES of cows in early lactation can be monitored with moderately high accuracy by routine milk measurements.

Nuclear magnetic resonance screening of changes in fatty acid and cholesterol content of ovine milk induced by ensiled olive cake inclusion in Chios sheep diets

Lipid supplementation of dairy ewe diets has been shown to introduce changes in the fatty acid (FA) profile and cholesterol content of milk. In the present study sheep were fed diets including ensiled olive cake (OC), a conserved by-product of olive oil production, and the lipid content of their milk was assessed in lyophilized samples with nuclear magnetic resonance (NMR) technique. Thirty lactating Chios ewes were allocated into three groups of ten animals fed isonitrogenous and isoenergetic diets which differed in the quantity of ensiled OC inclusion: G0, G500 and G1000 groups with 0, 500, 1000 g (on fresh weight basis) of ensiled OC inclusion per ewe, per day, respectively. Fat percentage, FA profile and cholesterol content were determined in milk samples collected after a 4-week feeding period. Results indicated that saturated FA were reduced by 7.2% and 11.3% in milk samples from the G500 and G1000 groups, respectively. Ensiled OC increased unsaturated FA content by 26.3% and 41.4% and monounsaturated FA content of milk by 30.3% and 45.6% in the G500 and G1000 groups, respectively. Furthermore, the inclusion of 1000 g ensiled OC significantly increased the content of beneficial for human health FA such as conjugated linoleic acids (CLA isomers: 9-cis, 11-trans CLA; 9-trans, 11-cis CLA and 10-trans, 12-cis CLA) by 47.2% and linoleic acid by 14.4% compared to control group. However, any rate of ensiled OC inclusion in the diets of ewes had no effect on milk cholesterol content or milk fat percentage. Overall, the present work provides novel experimental data with NMR fingerprinting of the lyophilized milk lipid fraction, and suggests the use of ensiled OC in sheep rations since it induces desirable changes in ovine milk lipids.

The use of mid-infrared spectra to map genes affecting milk composition

The aim of this study was to investigate the feasibility of using mid-infrared (MIR) spectroscopy analysis of milk samples to increase the power and precision of genome-wide association studies (GWAS) for milk composition and to better distinguish linked quantitative trait loci (QTL). To achieve this goal, we analyzed phenotypic data of milk composition traits, related MIR spectra, and genotypic data comprising 626,777 SNP on 5,202 Holstein, Jersey, and crossbred cows. We performed a conventional GWAS on protein, lactose, fat, and fatty acid concentrations in milk, a GWAS on individual MIR wavenumbers, and a partial least squares regression (PLS), which is equivalent to a multi-trait GWAS, exploiting MIR data simultaneously to predict SNP genotypes. The PLS detected most of the QTL identified using single-trait GWAS, usually with a higher significance value, as well as previously undetected QTL for milk composition. Each QTL tends to have a different pattern of effects across the MIR spectrum and this explains the increased power. Because SNP tracking different QTL tend to have different patterns of effect, it was possible to distinguish closely linked QTL. Overall, the results of this study suggest that using MIR data through either GWAS or PLS analysis applied to genomic data can provide a powerful tool to distinguish milk composition QTL.

Effect of dietary supplementation of sodium acetate and calcium butyrate on milk fat synthesis in lactating dairy cows

Acetate is a major source of energy and substrate for milk fat synthesis in the dairy cow. We recently reported a linear increase in milk fat yield and greater than a 30% net apparent transfer of acetate to milk fat with ruminal infusion of neutralized acetate. Additionally, ruminal acetate infusion linearly increases plasma β-hydroxybutyrate. The objective of the current study was to investigate the ability of acetate and butyrate fed in a diet to increase milk fat synthesis. Twelve multiparous lactating Holstein cows were randomly assigned to treatments in a 3 × 3 Latin square design with 14-d periods that included a 7-d washout followed by 7 d of treatment. Cows were fed ad libitum a basal diet with a low risk for biohydrogenation-induced milk fat depression, and treatments were mixed into the basal diet. Treatments were 3.2% NaHCO3 (control), 2.9% sodium acetate, and 2.5% calcium butyrate (carbon equivalent to acetate treatment) as a percent of diet dry matter. Feeding sodium acetate increased dry matter intake by 2.7 kg, had no effect on milk yield, and increased milk fat yield by 90 g/d and concentration by 0.2 percentage units, compared with control. Calcium butyrate decreased dry matter intake by 2.6 kg/d, milk yield by 1.65 kg/d, and milk fat yield by 60 g/d, compared with control. Sodium acetate increased concentration and yield of 16 carbon mixed source fatty acids (FA) and myristic acid, while decreasing the concentration of preformed FA, compared with control. Calcium butyrate had no effect on concentration of milk FA by source, but increased concentration of trans-10 C18:1 in milk by 18%, indicating a shift in rumen biohydrogenation pathways. Our data demonstrate that milk fat yield and concentration can be increased by feeding sodium acetate at 2.9% of diet dry matter, but not by feeding calcium butyrate at an equivalent carbon mass.

Potential of chia oil to enrich goats' milk with omega-3 fatty acids in comparison to linseed oil under tropical climate

To study the potential of Chia oil to enrich goats' milk with omega-3 fatty acids in comparison to Linseed oil (LSO) under tropical climate, twelve lactating goats (Beetal) divided into 3 groups (on the basis of milk yield and parity) and were randomly assigned control diet or supplemented with Linseed oil (LSO) or Chia oil as additive at 1% of dry matter intake for 60 days. Dietary inclusion of Linseed or Chia oil didn't affect DM intake, apparent dry matter digestibility, pH or total volatile fatty acid production in dairy goats, however, acetate and butyrate in LSO group and ammonical-N in Chia group were higher than control. Similarly, no significant changes were detected for milk yield and milk composition, but values were numerically higher in LSO and Chia supplemented groups in comparison to control group. Inclusion of Linseed oil improved proportion of α-linolenic acid in milk fat. Moreover, eicosapentaenoic acid and docosahexaenoic acid were significantly improved in LSO group only. Poly unsaturated fatty acid content in milk varied from 3.09 g/100 g fat (control) to 3.86 g/100 g fat in LSO supplemented group but the differences were statistically non-significant. The proportions of omega 3 fatty acids was enhanced by 75.0 and 31.9% in LSO and Chia groups over control group that led to decrease in ratio of n-6/n-3 FA and desaturase index. It can be concluded that dietary inclusion of both oils improved the fatty acid profile of goat's milk, but Chia oil is not as effective as Linseed oil under tropical climate.

Goat yoghurt drinks with elevated α-linolenic acid content and enriched with yacon fiber

Goat milk and goat milk products are very valuable in human nutrition because of their favorable nutrient composition which can be further boosted by the addition of prebiotic fiber and probiotic bacteria. It has also been possible to change the fatty acid profile of goat milk through feed composition. The aim of this study was to increase the nutritional value of goat milk by producing a probiotic yoghurt drink made from milk with elevated omega-3 fatty acids and enriched with natural yacon prebiotics. Goat nutrition is one of the key factors how we can naturally increase omega-3 fatty acid content in goat milk. In our study, twenty four White Shorthair goats were divided into the control and experimental group which was supplemented with 55 mL of linseed oil per day for eight weeks to increase the monounsaturated and polyunsaturated fatty acid content in the milk. The yoghurt milk drinks were formulated from individual goat milk samples with added bifidobacteria and yacon prebiotics. Our results showed that goat feed supplementation with linseed oil indeed positively changed fatty acid profile of goat milk in which α-linolenic acid content increased while, at the same time, lauric, myristic and palmitic acid contents decreased. Also, yoghurt drinks enriched with yacon prebiotics have shown higher bifidobacteria counts compared to the control.

Differential effects of oilseed supplements on methane production and milk fatty acid concentrations in dairy cows

It is known that supplementing dairy cow diets with full-fat oilseeds can be used as a strategy to mitigate methane emissions, through their action on rumen fermentation. However, direct comparisons of the effect of different oil sources are very few, as are studies implementing supplementation levels that reflect what is commonly fed on commercial farms. The objective was to investigate the effect of feeding different forms of supplemental plant oils on both methane emissions and milk fatty acid (FA) profile. Four multiparous, Holstein-Friesian cows in mid-lactation were randomly allocated to one of four treatment diets in a 4×4 Latin square design with 28-day periods. Diets were fed as a total mixed ration with a 50 : 50 forage : concentrate ratio (dry matter (DM) basis) with the forage consisting of 75 : 25 maize silage : grass silage (DM). Dietary treatments were a control diet containing no supplemental fat, and three treatment diets containing extruded linseed (EL), calcium salts of palm and linseed oil (CPLO) or milled rapeseed (MR) formulated to provide each cow with an estimated 500 g additional oil/day (22 g oil/kg diet DM). Dry matter intake (DMI), milk yield, milk composition and methane production were measured at the end of each experimental period when cows were housed in respiration chambers for 4 days. There was no effect of treatment diet on DMI or milk protein or lactose concentration, but oilseed-based supplements increased milk yield compared with the control diet and milk fat concentration relative to control was reduced by 4 g/kg by supplemental EL. Feeding CPLO reduced methane production, and both linseed-based supplements decreased methane yield (by 1.8 l/kg DMI) and intensity (by 2.7 l/kg milk yield) compared with the control diet, but feeding MR had no effect on methane emission. All the fat supplements decreased milk total saturated fatty acid (SFA) concentration compared with the control, and SFA were replaced with mainly cis-9 18:1 but also trans FA (and in the case of EL and CPLO there were increases in polyunsaturated FA concentration). Supplementing dairy cow diets with these oilseed-based preparations affected milk FA profile and increased milk yield. However, only the linseed-based supplements reduced methane production, yield or intensity, whereas feeding MR had no effect.

Changes in fatty acid profile of Bovec sheep milk due to different pasture altitude

Sheep rearing on mountain pastures is an ancestral tradition in northwestern Slovenia. The indigenous Bovec sheep are widespread there and are well adapted to the rough Alpine rearing conditions. Every year, after weaning, the sheep start grazing in the lowlands (L) and then gradually move to mountain pastures, and finally, to the highland (H) pastures of the Alps. Grazing positively affects the fatty acid (FA) composition in sheep milk fat with increased availability of polyunsaturated FA (PUFA) in grass, and subsequently, in milk. Consequently, the objective of this work was to study the FA profile in sheep milk during grazing in four geographical areas in the Alps. A total of 15 ewes of the Bovec sheep breed were randomly selected and milk samples from these ewes were taken at four different pasture locations that differed with regard to altitude: the L pasture location at an altitude of 480 m, the mountain pastures (M1 and M2) at altitudes of 1100 to 1300 m and 1600 to 1900 m, respectively, and the H pastures at altitudes of 2100 to 2200 m. Milk samples from the ewes were taken during the grazing season from April to September. The chemical and FA composition of the milk samples from each pasture location were determined. There were significant differences in the concentrations of FA among the L, M1, M2 and H milk samples. We observed decreases of the concentrations of saturated FA (SFA) in milk from L to H pastures. The concentration of α-linolenic FA, monounsaturated FA (MUFA), PUFA and n-3 PUFA in milk were increased significantly with pasture altitude. The n-6/n-3 PUFA ratio was reduced by the change of pasture altitude with the lowest value at the M1 pasture (1.5). The concentrations of total SFA decreased significantly and was lowest at the L pasture. Our results underline the importance of the effect of grazing in the Alpine region associated with pasture altitude on the FA profile of sheep milk. The first variation in FA concentration in sheep milk occurred between L and M1, although it was more evident on H pastures in the Alpine mountains. Changes of the FA profile in sheep milk due to pasture altitude were related to variation in FA concentration in the pasture and the botanical composition of the pasture location.

Relations between feces, urine, milk and blood fatty acid contents in cattle

The various fatty acids found in the circulation, cells and tissues of animals that have an important place in the feeding of animals are important components of cell membranes related to events that occur in a rich source of energy and cells. Since the fatty acids groups having important functions can not be synthesized by the mammalian cells, they must be taken from the outside of the body. Fatty acids detected in blood, feces, milk and urine can be an indicator to diagnose some metabolic disorders. This study was conducted to investigate the correlation between fecal matter, urine, milk and blood fatty acid contents in Holstein cows by multiple regression analysis. As a result, milk, blood, stool and urine fatty acid contents were statistically significantly related to each other (p &lt;0.01).