Cis-9 C18 Research Articles

Pd0–Ov–Ce3+ Interfacial Sites with Charge Redistribution for Enhanced Hydrogenation of Methyl Oleate to Methyl Stearate

Improving the efficiency of metal/reducible metal oxide interfacial sites for hydrogenation reactions of unsaturated groups (e.g., C=C and C=O) is a promising yet challenging endeavor. In our study, we developed a Pd/CeO2 catalyst by enhancing the oxygen vacancy (OV) concentration in CeO2 through high-temperature treatment. This process led to the formation of an interface structure ideal for supporting the hydrogenation of methyl oleate to methyl stearate. Specifically, metal Pd0 atoms bonded to the OV in defective CeO2 formed Pd0–OV–Ce3+ interfacial sites, enabling strong electron transfer from CeO2 to Pd. The interfacial sites exhibit a synergistic adsorption effect on the reaction substrate. Pd0 sites promote the adsorption and activation of C=C bonds, while OV preferably adsorbs C=O bonds, mitigating competition with C=C bonds for Pd0 adsorption sites. This synergy ensures rapid C=C bond activation and accelerates the attack of active H* species on the semi-hydrogenated intermediate. As a result, our Pd/CeO2-500 catalyst, enriched with Pd0–OV–Ce3+ interfacial sites, demonstrated excellent hydrogenation activity at just 30 °C. The catalyst achieved a Cis–C18:1 conversion rate of 99.8% and a methyl stearate formation rate of 5.7 mol/(h·gmetal). This work revealed the interfacial sites for enhanced hydrogenation reactions and provided ideas for designing highly active hydrogenation catalysts.

Metabolite profiling of different Iranian traditional yogurts using an untargeted metabolomics approach

We used gas chromatography-mass spectrometry (GC-MS) with an untargeted metabolomics approach to look at the metabolite profiles of traditional Iranian yogurts made from cow, goat, buffalo, and sheep milk. Results showed that different animal milks significantly influenced physicochemical properties and fatty acid (FA) composition, resulting in diverse metabolites. Over 80 % of all the fatty acids in the yogurt samples were saturated. The main fatty acids found were myristic acid (C14:0), palmitic acid (C16:0), and oleic acid + petroselenic acid (cis-9 C18:1 + cis-6 C18:1). In total, 36 metabolites, including esters, aldehydes, alcohols, and acids, were detected. Some important metabolites that changed yogurt profiles were 2-heptanone, methyl acetate, 2-propanone, butyl formate, and 4-methyl benzal. Associations between metabolite profiles and milk compositional traits were also observed, with statistical models showing a strong correlation between metabolite profiles and FA content. This study is the first to explore the impact of different animal sources and regions in Iran on the metabolome profiles of traditional yogurts. These results give us useful information about how metabolites differ between species and can be used to make new dairy products based on milk compositions and metabolites, which will help with future formulations of autochthonous starters.

Effects of altering the ratio of C16:0 and cis-9 C18:1 in rumen bypass fat on growth performance, lipid metabolism, intestinal barrier, cecal microbiota, and inflammation in fattening bulls

BackgroundC16:0 and cis-9 C18:1 may have different effects on animal growth and health due to unique metabolism in vivo. This study was investigated to explore the different effects of altering the ratio of C16:0 and cis-9 C18:1 in fat supplements on growth performance, lipid metabolism, intestinal barrier, cecal microbiota, and inflammation in fattening bulls. Thirty finishing Angus bulls (626 ± 69 kg, 21 ± 0.5 months) were divided into 3 treatments according to the randomized block design: (1) control diet without additional fat (CON), (2) CON + 2.5% palmitic acid calcium salt (PA, 90% C16:0), and (3) CON + 2.5% mixed fatty acid calcium salt (MA, 60% C16:0 + 30% cis-9 C18:1). The experiment lasted for 104 d, after which all the bulls were slaughtered and sampled for analysis.ResultsMA tended to reduce 0–52 d dry matter intake compared to PA (DMI, P = 0.052). Compared with CON and MA, PA significantly increased 0–52 d average daily gain (ADG, P = 0.027). PA tended to improve the 0–52 d feed conversion rate compared with CON (FCR, P = 0.088). Both PA and MA had no significant effect on 52–104 days of DMI, ADG and FCR (P > 0.05). PA tended to improve plasma triglycerides compared with MA (P = 0.077), significantly increased plasma cholesterol (P = 0.002) and tended to improve subcutaneous adipose weight (P = 0.066) when compared with CON and MA. Both PA and MA increased visceral adipose weight compared with CON (P = 0.021). Only PA increased the colonization of Rikenellaceae, Ruminococcus and Proteobacteria in the cecum, and MA increased Akkermansia abundance (P < 0.05). Compared with CON, both PA and MA down-regulated the mRNA expression of Claudin-1 in the jejunum (P < 0.001), increased plasma diamine oxidase (DAO, P < 0.001) and lipopolysaccharide (LPS, P = 0.045). Compared with CON and MA, PA down-regulated the ZO-1 in the jejunum (P < 0.001) and increased plasma LPS-binding protein (LBP, P < 0.001). Compared with CON, only PA down-regulated the Occludin in the jejunum (P = 0.013). Compared with CON, PA and MA significantly up-regulated the expression of TLR-4 and NF-κB in the visceral adipose (P < 0.001) and increased plasma IL-6 (P < 0.001). Compared with CON, only PA up-regulated the TNF-α in the visceral adipose (P = 0.01). Compared with CON and MA, PA up-regulated IL-6 in the visceral adipose (P < 0.001), increased plasma TNF-α (P < 0.001), and reduced the IgG content in plasma (P = 0.035). Compared with CON, PA and MA increased C16:0 in subcutaneous fat and longissimus dorsi muscle (P < 0.05), while more C16:0 was also deposited by extension and desaturation into C18:0 and cis-9 C18:1. However, neither PA nor MA affected the content of cis-9 C18:1 in longissimus dorsi muscle compared with CON (P > 0.05).ConclusionsMA containing 30% cis-9 C18:1 reduced the risk of high C16:0 dietary fat induced subcutaneous fat obesity, adipose tissue and systemic low-grade inflammation by accelerating fatty acid oxidative utilization, improving colonization of Akkermansia, reducing intestinal barrier damage, and down-regulating NF-κB activation.

Effect of changing the proportion of C16:0 and cis-9 C18:1 in fat supplements on rumen fermentation, glucose and lipid metabolism, antioxidation capacity, and visceral fatty acid profile in finishing Angus bulls

This study evaluated the effects of different proportions of palmitic (C16:0) and oleic (cis-9 C18:1) acids in fat supplements on rumen fermentation, glucose (GLU) and lipid metabolism, antioxidant function, and visceral fat fatty acid (FA) composition in Angus bulls. The design of the experiment was a randomized block design with 3 treatments of 10 animals each. A total of 30 finishing Angus bulls (21 ± 0.5 months) with an initial body weight of 626 ± 69 kg were blocked by weight into 10 blocks, with 3 bulls per block. The bulls in each block were randomly assigned to one of three experimental diets: (1) control diet without additional fat (CON), (2) CON + 2.5% palmitic calcium salt (PA; 90% C16:0), (3) CON + 2.5% mixed FA calcium salts (MA; 60% C16:0 + 30% cis-9 C18:1). Both fat supplements increased C18:0 and cis-9 C18:1 in visceral fat (P < 0.05) and up-regulated the expression of liver FA transport protein 5 (FATP5; P < 0.001). PA increased the insulin concentration (P < 0.001) and aspartate aminotransferase activity (AST; P = 0.030) in bull's blood while reducing the GLU concentration (P = 0.009). PA increased the content of triglycerides (TG; P = 0.014) in the liver, the content of the C16:0 in visceral fat (P = 0.004), and weight gain (P = 0.032), and up-regulated the expression of liver diacylglycerol acyltransferase 2 (DGAT2; P < 0.001) and stearoyl-CoA desaturase 1 (SCD1; P < 0.05). MA increased plasma superoxide dismutase activity (SOD; P = 0.011), reduced the concentration of acetate and total volatile FA (VFA) in rumen fluid (P < 0.05), and tended to increase plasma non-esterified FA (NEFA; P = 0.069) concentrations. Generally, high C16:0 fat supplementation increased weight gain in Angus bulls and triggered the risk of fatty liver, insulin resistance, and reduced antioxidant function. These adverse effects were alleviated by partially replacing C16:0 with cis-9 C18:1.

Enhancing milk quality and modulating rectal microbiota of dairy goats in starch-rich diet: the role of bile acid supplementation.

Diets rich in starch have been shown to increase a risk of reducing milk fat content in dairy goats. While bile acids (BAs) have been used as a lipid emulsifier in monogastric and aquatic animals, their effect on ruminants is not well understood. This study aimed to investigate the impact of BAs supplementation on various aspects of dairy goat physiology, including milk composition, rumen fermentation, gut microbiota, and BA metabolism. We randomly divided eighteen healthy primiparity lactating dairy goats (days in milk = 100 ± 6 d) into two groups and supplemented them with 0 or 4g/d of BAs undergoing 5weeks of feeding on a starch-rich diet. The results showed that BAs supplementation positively influenced milk yield and improved the quality of fatty acids in goat milk. BAs supplementation led to a reduction in saturated fatty acids (C16:0) and an increase in monounsaturated fatty acids (cis-9 C18:1), resulting in a healthier milk fatty acid profile. We observed a significant increase in plasma total bile acid concentration while the proportion of rumen short-chain fatty acids was not affected. Furthermore, BAs supplementation induced significant changes in the composition of the gut microbiota, favoring the enrichment of specific bacterial groups and altering the balance of microbial populations. Correlation analysis revealed associations between specific bacterial groups (Bacillus and ChristensenellaceaeR-7group) and BA types, suggesting a role for the gut microbiota in BA metabolism. Functional prediction analysis revealed notable changes in pathways associated with lipid metabolism, suggesting that BAs supplementation has the potential to modulate lipid-related processes. These findings highlight the potential benefits of BAs supplementation in enhancing milk production, improving milk quality, and influencing metabolic pathways in dairy goats. Further research is warranted to elucidate the underlying mechanisms and explore the broader implications of these findings.

Effects of dietary palmitic acid and oleic acid ratio on milk production, nutrient digestibility, blood metabolites, and milk fatty acid profile of lactating dairy cows

Adequate energy supply is a crucial factor for maintaining the production performance in early lactating cows. Adding fatty acids to diets can improve energy supply, while the effect could be related to the chain length and degree of saturation of fatty acids. This study was conducted to evaluate the effect of different ratios of palmitic acid (C16:0) to oleic acid (cis-9 C18:1) on the production performance, nutrient digestibility, blood metabolites and milk fatty acids profile in early lactating dairy cows. Seventy-two multiparous Holstein cows (63.5 ± 2.61 d in milk) blocked by parity (2.39 ± 0.20), body weight (668.3 ± 20.1 kg), body condition score (3.29 ± 0.06), and milk yield (47.9 ± 1.63 kg) were used in a completely randomized design. Cows were divided into 3 groups with 24 cows in every group. Cows in 3 treatments were provided iso-energy and iso-nitrogen diets, whereas the C16:0 to cis-9 C18:1 ratio was different: (1) 90.9% C16:0 + 9.1% cis-9 C18:1 (90.9:9.1); (2) 79.5% C16:0 + 20.5% cis-9 C18:1 (79.5:20.5); (3) 72.7% C16:0 + 27.3% cis-9 C18:1 (72.7:27.3). Fatty acids were added at 1.3% in dry matter basis. Although the dry matter intake fat-corrected milk yield and energy-corrected milk yield were not affected, the milk yield, milk protein yield and feed efficiency increased linearly with the increasing of cis-9 C18:1 ratio. The milk protein percentage and milk fat yield did not differ among treatments, whereas the milk fat percentage tended to decrease linearly with the increasing of cis-9 C18:1 ratio. The lactose yield increased linearly and lactose percentage tended to increase linearly with increasing cis-9 C18:1 ratio, whereas the percentage of milk total solids and somatic cell count decreased linearly. Though the changes of body condition score were not affected by treatments, the body weight loss decreased linearly with the increasing of cis-9 C18:1 ratio. The effect of treatment on nutrient digestibility was limited, except a linear increase in ether extract and neutral detergent fiber digestibility with the increasing of cis-9 C18:1 ratio. There was a linear increase in the concentrations of plasma glucose, whereas the triglyceride and nonesterified fatty acid concentration decreased linearly with the increasing of cis-9 C18:1 ratio. As the cis-9 C18:1 ratio increased, the concentration of de novo fatty acids decreased quadratically, while the mixed and preformed fatty acids increased linearly. In conclusion, increasing cis-9 C18:1 ratio could increase production performance and decrease body weight loss by increasing nutrient digestibility, and the ratio had the most powerful beneficial effect on early lactating cows suggested by 72.7:27.3.

Milk production responses of dairy cows to fatty acid supplements with different ratios of palmitic and oleic acids in low- and high-fat basal diets

We evaluated the effects of fatty acid (FA) supplements with different ratios of palmitic acid (C16:0) and oleic acid (cis-9 C18:1) in low- and high-FA basal diets on production responses of lactating dairy cows. Thirty-six multiparous Holstein cows (50.2 ± 5.8 kg/d of milk; 160 ± 36 d in milk) were used in a split-plot Latin square design balanced for carryover effects. Cows were blocked by milk yield and allocated to a main plot receiving either a low-FA (LF; 1.93% FA content) basal diet (n = 18) containing cottonseed meal and cottonseed hulls or a high-FA (HF; 3.15% FA content) basal diet (n = 18) containing whole cottonseed. Within each plot, a 3 × 3 Latin square arrangement of treatments was used in 3 consecutive 21-d periods. Treatments were (1) control (CON; no FA supplementation), (2) FA supplement containing 80% C16:0 + 10% C18:1 (PA), and (3) FA supplement containing 60% C16:0 + 30% cis-9 C18:1 (PA+OA). The FA supplements were fed at 1.5% of dry matter and replaced soyhulls in CON. Preplanned contrasts were (1) overall effect of FA supplementation {CON vs. the average of the FA treatments [1/2 (PA + PA+OA)]}, and (2) the effect of the PA treatment versus the PA+OA treatment (PA vs. PA+OA). Treatment by basal diet interactions were observed for yields of milk and lactose, where FA treatments increased yields of milk and milk lactose in LF but not in HF. Basal diet had no effect on dry matter intake (DMI) or milk yield. Compared with LF, HF increased milk fat yield and 3.5% fat-corrected milk (FCM) and tended to increase milk fat content and energy-corrected milk (ECM) yield. The FA treatments decreased DMI but increased the yields of milk fat, 3.5% FCM, and ECM, compared with CON, due to increases in mixed and preformed milk FA yields. The PA+OA treatment decreased DMI and milk protein yield compared with PA. In conclusion, a high-fat basal diet increased milk fat production, and the addition of FA supplements to a low-fat basal diet increased milk lactose yield and tended to increase milk yield. Additionally, regardless of basal diet fat level, FA supplements increased production responses compared with the non-FA-supplemented control diet.

Chemical and Fatty Acids Composition of Yak Milk from Qinghai-Tibetan Plateau in Different Seasons

Background: Yak milk is the main source of dietary protein, fat and micronutrients for Qinghai-Tibetan Plateau residents. However, few studies have focused on the seasonal variation of nutritional components in natural grazing (without supplementary feeding) yak milk. Methods:Yaks living at high altitudes (average altitude of more than 4200 metre) were selected (summer, n=18; winter, n=18; spring, n=15) to analyzed seasonal influence on chemical and fatty acids composition of yak milk. Result: Results showed that the contents of fat, protein, lactose, non-fat milk solid, vitamin A and the main fatty acids (C6:0, C12:0, C14:0, C15:0, C16:0, C17:0, C20:0, cis-9 C16:1, cis-9 C18:1, trans-9 C18:1, LA, etc.) in winter yak milk were significantly different from those in summer and spring yak milk (p less than 0.05). This suggests that chemical and fatty acids composition of yak milk were influenced by seasons.

Increasing palmitic acid and reducing stearic acid content of supplemental fatty acid blends improves production performance of mid-lactation dairy cows

We determined the effects of altering the ratio of palmitic (C16:0) and stearic (C18:0) acids in supplemental fatty acid (FA) blends on production responses of mid-lactation dairy cows. Twenty-four multiparous Holstein cows (mean ± standard deviation; 47.1 ± 5.8 kg of milk yield, 109 ± 23 DIM) were randomly assigned to treatment sequences in a replicated 4 × 4 Latin square design with 21-d periods. Treatments were a control diet not supplemented with FA (CON), and 3 diets incorporating 1.5% of dry matter (DM) FA supplement blends containing 30% C16:0 + 50% C18:0, 50% C16:0 + 30% C18:0, and 80% C16:0 + 10% C18:0. Additionally, the FA blends were balanced to contain 10% of oleic acid (cis-9 C18:1). The FA blends replaced soyhulls in the CON diet. Diets were formulated to contain (% of DM) 31.0% neutral detergent fiber, 27.0% starch, and 16.9% crude protein. The statistical model included the random effect of cow within square and the fixed effects of period, treatment, and their interaction. Preplanned contrasts included CON versus overall effect of FA supplementation and the linear and quadratic effects of increasing C16:0 in FA blends. Overall FA treatment had no effect on dry matter intake (DMI), but increasing C16:0 linearly increased DMI. Compared with CON, overall FA treatment increased yields of milk, 3.5% of fat-corrected milk, energy-corrected milk, and milk fat but did not affect milk protein yield. Increasing C16:0 linearly increased milk fat yield and tended to linearly increase the yields of 3.5% of fat-corrected milk and energy-corrected milk. Fatty acid supplementation decreased the yield of de novo milk FA but increased yields of mixed and preformed milk FA compared with CON. Increasing C16:0 in FA treatments did not affect the yield of de novo milk FA, linearly increased the yield of mixed, and decreased the yield of preformed milk FA. In summary, feeding FA supplements containing C16:0 and C18:0 increased milk production responses with no effect on DMI compared with a control diet. Mid-lactation cows producing ∼40 to 50 kg/d milk yield responded best to increasing supplemental C16:0 in FA supplements, demonstrating that FA supplements higher in C16:0 and limited in C18:0 improves production responses.

Effects of Phlorotannins from Sargassum on In Vitro Rumen Fermentation, Microbiota and Fatty Acid Profile.

The fatty acid profiles of ruminant-derived products are closely associated with human health. Ruminal microbiota play a vital role in modulating rumen biohydrogenation (BH). The aim of this study was to assess the influence of dietary supplementation with phlorotannins (PTs) extracted from Sargassum on rumen fermentation, fatty acid composition and bacterial communities by an in vitro culture study. The inclusion of PTs in the diet increased dry matter digestibility and gas production, and reduced ammonia-N concentration and pH. PT extract inhibited rumen BH, increasing the content of trans-9 C18:1, cis-9 C18:1, trans-9 and trans-12 C18:2 and reducing C18:0 concentration. 16S rRNA sequencing revealed that PTs caused an obvious change in rumen bacterial communities. The presence of Prevotella decreased while carbohydrate-utilizing bacteria such as Prevotellaceae_UCG-001, Ruminococcus, Selenomonas, Ruminobacter and Fibrobacter increased. Correlation analysis between rumen FA composition and the bacterial microbiome revealed that Prevotellaceae_UCG-001, Anaerovorax, Ruminococcus, Ruminobacter, Fibrobacter, Lachnospiraceae_AC2044_group and Clostridia_UCG-014 might have been involved in the BH process. In conclusion, the results suggest that the inclusion of PTs in the diet improved rumen fermentation and FA composition through modulating the rumen bacterial community.

Feeding graded levels of camelina expeller meal up to 20% of dietary dry matter decreases feed intake and milk production but enhances concentration in milk fat of n-3 fatty acids in dairy cows

Eight Holstein cows were used in a replicated 4 × 4 Latin square design study to determine the effects of feeding 0%, 10%, 15%, and 20% camelina expeller meal (CEM) on production and milk fatty acid profiles. Dry matter intake (DMI) and milk fat content decreased linearly, whereas milk yield decreased quadratically, as CEM increased. Concentrations in milk fat of C18:2n-6 and cis-9, trans-11 C18:2 increased linearly, whereas those of C18:3n-3 and trans-10, cis-12 C18:2 increased quadratically as CEM increased. Results show that CEM levels up to 20% decrease DMI and milk yield but increase concentrations in milk fat of desirable n-3 fatty acids.

Abomasal infusion of oleic acid and exogenous emulsifier alter fatty acid digestibility and production responses of lactating dairy cows

We evaluated the effects of abomasal infusion of cis-9 C18:1 (oleic acid) and an exogenous emulsifier (polysorbate-C18:1) on fatty acid (FA) digestibility and production responses of dairy cows. Eight rumen-cannulated multiparous cows (96 ± 23 d in milk) were assigned to a 2 × 2 factorial arrangement of treatments in 4 × 4 Latin squares with 18-d periods consisting of 7 d of washout and 11 d of infusion. Treatments were abomasal infusions of water carrier only (CON), 45 g/d oleic acid (OA), 20 g/d polysorbate-C18:1 (T80), or both 45 g/d OA and 20 g/d T80 (OA+T80). The OA treatments were dissolved in ethanol and the T80 treatments in water. To deliver the daily dose for each treatment, the infusate solution was divided into 4 equal infusions per day, occurring every 6 h. Cows were fed the same diet, which contained [% of dry matter (DM)] 30.3% neutral detergent fiber (NDF), 16.3% crude protein, 30% starch, and 3.2% FA (including 1.8% DM from a FA supplement containing 34.4% C16:0 and 47.7% C18:0). Infusion of T80 increased NDF digestibility compared with all other treatments (3.57 percentage units), whereas OA+T80 decreased NDF digestibility compared with CON (3.30 percentage units). Compared with CON, OA (4.90 percentage units) and T80 (3.40 percentage units) increased total FA digestibility, whereas OA+T80 had no effect on total FA digestibility. We did not observe differences between OA and T80 for total FA digestibility. Infusion of OA (3.90 percentage units) and T80 (2.80 percentage units) increased 16-carbon FA digestibility compared with CON. Digestibility of 16-carbon FA did not differ between OA and T80 or between CON and OA+T80. Compared with CON, OA increased (5.60 percentage units) and T80 tended to increase 18-carbon FA digestibility. Digestibility of 18-carbon FA did not differ between OA and T80 or between CON and OA+T80. Compared with CON, all treatments increased or tended to increase the absorption of total and 18-carbon FA. Infusion of OA and T80 increased the yields of milk fat (both increased 0.10 kg/d), 3.5% fat-corrected milk (1.90 and 2.50 kg/d), and energy-corrected milk (1.80 and 2.60 kg/d) compared with CON. We did not observe differences between OA and T80 or between CON and OA+T80 for yields of milk fat, 3.5% fat-corrected milk, or energy-corrected milk. Infusing OA tended to increase plasma insulin concentration compared with CON. Compared with the other treatments, OA+T80 decreased the yield of de novo milk FA (31.3 g/d). Compared with CON, OA tended to increase the yield of de novo milk FA. Compared with OA+T80, CON and OA tended to increase the yield of mixed milk FA, whereas T80 increased it (83 g/d). Compared with CON, all emulsifier treatments increased the yield of preformed milk FA (52.7 g/d). In conclusion, abomasally infusing either 45 g of OA or 20 g of T80 improved digestibility and similarly favored the production parameters of dairy cows. In contrast, providing both (45 g of OA + 20 g of T80) had no additional benefits and moderated the positive responses observed in the individual treatments with OA and T80.

Variety of rumen microbial populations involved in biohydrogenation related to individual milk fat percentage of dairy cows.

Our objective was to investigate the contribution of the rumen microbiome on the individual milk fat percentage (MFP) of Holstein dairy cows under the same nutritional and management conditions. From 92 early lactation dairy cows, the top 10 with the highest MFP (HF; n = 10) and the last 10 with the lowest MFP (LF; n = 10) were selected for the study. As a result, the milk trans-10, cis-12 C18:2 content was significant lower in the HF group than that in the LF group (P < 0.001). The rumen acetate to propionate ratio was significant higher in the HF group than that in the LF group (P = 0.035). According to the results of 16S rRNA gene sequencing, a minor but significant difference existed between the groups (P = 0.040). Three genera of the family Lachnospiraceae and four genera of the order Bacteroidales were identified to be the biomarkers for the LF group and HF group in the LEfSe analysis, respectively. Three microbial modules enriched by the family Lachnospiraceae were positively related to the milk trans-10, cis-12 C18:2 content (r s > 0.60, P < 0.05). According to the results of shotgun metagenome sequencing, three kinds of linoleic acid (LA) isomerase genes were present in the gene pools of the rumen microbiome. Among them, the relative abundance of Bifidobacterium LA isomerase (BBI) was higher in the HF group than that in the LF group (P = 0.007). Three metagenome-assembled genomes (MAGs) with LA isomerase genes were positively correlated to the milk trans-10, cis-12 C18:2 content (r s > 0.40, P < 0.05). Furthermore, all of these three MAGs were found to be able to produce lactate. Taken together, these results indicate that the increased relative abundance of microbial population with the trans-10 biohydrogenation pathway within the rumen microbiome contributes to the decrease of MFP via the increase of rumen trans-10, cis-12 C18:2 production. This study provides a new perspective for the development of measures for improving the milking performance of dairy cows.

Live yeasts as a non-hormonal alternative to improve the performance of dairy cows

The present study aimed to evaluate live yeast dietary supply instead of rbST application in lactating dairy cows. Thirty-five Holstein cows (37.1 ± 7.8 kg/d of milk yield and 524 ± 27 kg of body weight; mean ± SD) were used in a completely random trial to evaluate: 1) rbST: animals treated with 500 mg of rbST every 14 d; and 2) Yeast: animals fed diets containing 40 g/d of live yeast. The trial lasted for five subsequent 14-d periods. Treatments showed no effects on cows’ feed intake. Yeast reduced large and small particles selection indexes compared, feed residue and starch in feces compared to rbST. Cows treated with rbST had increased glucose, triglycerides, and AST, and decreased cholesterol and urea serum concentration. In addition, yeast reduced somatic cells count and increased milk yield and cows’ production efficiency. Although treatments showed no effects on milk chemical composition, yeast increased saturated to unsaturated fatty acids ratio. Yeast increased saturated and short-chain fatty acids, whereas reduced unsaturated and cis-9 trans-11 C18:2 FA content in milk fat. Thus, yeast could be used instead of rbST to improve milk yield and the productive efficiency of cows in a short-term evaluation

Altering the ratio of palmitic, stearic, and oleic acids in dietary fat affects nutrient digestibility, plasma metabolites, growth performance, carcass, meat quality, and lipid metabolism gene expression of Angus bulls

This study evaluated the effects of changing the ratio of palmitic, stearic, and oleic acids in dietary fat on nutritional metabolism, growth performance, and meat quality of finishing Angus bulls. Bulls received the following three treatments: (1) a control diet without fat supplement (CON), (2) CON + mixed fatty acid supplement (58% C16:0 + 28% cis-9 C18:1; MIX), (3) CON + saturated fatty acid supplement (87% C16:0 + 10% C18:0; SFA). In summary, both fat treatment diets simultaneously increased saturated fatty acids C16:0 (P = 0.025), C18:0 (P < 0.001) and total monounsaturated fatty acids (P = 0.008) in muscle, thus balancing the ratio of unsaturated to saturated fatty acids in muscle. MIX diet increased the digestibility of dry matter (P = 0.014), crude protein (P = 0.038), and ether extract (P = 0.036). SFA diet increased the daily gain (P = 0.032) and intramuscular fat content (P = 0.043). The high content of C16:0 and C18:0 in the SFA diet promoted weight gain and fat deposition of beef cattle by increasing feed intake, up-regulating the expression of lipid uptake genes and increasing deposition of total fatty acids, resulting in better growth performance and meat quality.

The Effect of Dietary Inclusion of Microalgae Schizochytrium spp. on Ewes' Milk Quality and Oxidative Status.

An unprecedented challenge for nutritionists arises during the 21st century in order to produce highly nutritious and functional food which promotes human health. Polyunsaturated fatty acids (PUFA) that are highly contained in microalgae have broadly been confirmed for preventing cardiovascular diseases and regulating immune-oxidative status. However, their optimum dietary inclusion level needs to be defined since PUFA are prone to oxidation. For this purpose, 24 cross-bred dairy ewes, were separated into four groups (n = 6) and were fed with different levels of microalgae Schizochytrium spp. [0 (CON, no microalgae), 20 (SC20), 30 (SC30) and 40 (SC40) g/ewe/day] for 60 days. The results showed that although the production parameters were not impaired, milk fat content was decreased in medium and high-level supplemented groups while protein content was suppressed only for the medium one. Concerning the fatty acids (FA) profile, the proportions of C14:0, trans C18:1, trans-11 C18:1, cis-9, trans-11 C18:2, trans-10, cis-12 C18:2, C20:5 (EPA), C22:5n-6 (DPA), C22:6n-3 (DHA), the total ω3 FA and PUFA were significantly increased, while those of C18:0, cis-9 C18:1 and C18:2n-6c were decreased in the milk of treated ewes. Additionally, in the S40 group an oxidative response was induced, observed by the increased malondialdehyde (MDA) levels in milk and blood plasma. In conclusion, the dietary inclusion of 20 g Schizochytrium spp./ewe/day, improves milks’ fatty acid profile and seems to be a promising way for producing ω3 fatty acid-enriched dairy products.

Acipimox Induces the Hepatic Accumulation of Long‐Chain Diacylglycerides and Triglycerides in Severely Burned Sprague Dawley Rats

ObjectivePersistent lipolysis is a hallmark of severe burns, contributing to futile triglyceride cycling and the accumulation of lipid in ectopic tissues. It has been suggested that the administration of acipimox, a potent inhibitor of lipolysis, may blunt the hypermetabolic response to burns. However, what impact massive burns has on the accumulation of individual lipid species in the liver and how this is affected by acipimox treatment is unknown.HypothesisWe hypothesize that large burns results in the accumulation of lipotoxic species within the liver and that this can be prevented by administering acipimox.MethodsThirty‐two male Sprague Dawley rats were randomized to receive either a scald burn (~60% total body surface area) or sham procedure, performed under isoflurane general anesthesia. Afterwards, animals were further randomized to receive either acipimox (50 mg/kg/day) or vehicle (saline) by i.p. injection administered once a day for 7 days. On day 7, animals were euthanized and the liver snap frozen in liquid nitrogen. Liver lipids were extracted by using a chloroform:methanol (2:1) solution and diacylglycerol (DAG), triacylglycerol (TAG), free fatty acids (FFA) and cholesterol esters (CE) separated by thin‐layer chromatography. Afterwards, individual lipid classes were esterified to methyl esters, derivatized using heptane, and analyzed by gas chromatography (GC). The fatty acids C16:0, C18:0, cis/trans C18:1, cis 18:2, C20:0, C22:0, C24:0, and C22:6 were resolved by GC for each of the lipid classes examined.ResultsLiver weights were comparable between groups. Burn injury had no significant effect on the concentration of liver lipids compared to sham treated animals, irrespective of lipid class (P &gt; 0.05). In contrast, the administration of acipimox significantly increased liver C16:0 (2.1‐fold; P &lt; 0.05), trans C18:1 (2.5‐fold; P &lt; 0.05), and cis C18:2 (5.5‐fold; P &lt; 0.05) TAG content in burned animals, when compared to injured animals treated with vehicle. No effect of acipimox on liver lipids was observed in sham treated animals.ConclusionContrary to expectations, acipimox causes the accumulation of long‐chain TAGs in rat liver following massive burns, but this is not observed in response to burn injury alone. The ability of acipimox to cause unwanted hepatic metabolic side effects warrants further investigation before it is used clinically to treat massive burns.

Effect of geographical origin on lipid content and fatty acids composition of bee collected pollen

Among the essential nutrients found in bee pollen, lipids comprise one of its principal and widely researched compounds with variable content and fatty acids composition depending on pollen’s botanical and geographical origin. Although plant source effect on pollen lipids has been partially studied, the impact of geographical origin remains unclear and also, the analysis of polyfloral pollen samples from diverse regions may lead to inaccurate results. Thus, in the present study, monofloral bee pollen samples, Cistus criticus, and Sinapis arvensis, were collected from different areas to identify the effect of geographical origin on pollen lipid profile, excluding the impact of botanical origin. The total lipid content of Cistus pollen ranged from 2.50% to 3.24% and of Sinapis pollen from 7.64% to 9.06%, while statistically significant differences were found among the studied areas, both for the two species. However, it seems that regardless of origin, Sinapis pollen is a rich source of total lipid content, contrary to Cistus pollen. Likely, it was found that geographical origin affected their fatty acid composition. The presence of oleic acid (cis C18:1) was dominant in all Cistus pollen samples and ranged from 50.75% (Central Macedonia) to 65.78% (Attiki), while all Sinapis pollen samples exhibited high content of alpha-linolenic acid (C18:3), with the low average percentage (41.71%) found in Crete and the highest (52.94%) in Central Macedonia. The results showed that the determination of geographical origin effect on lipids profile of bee pollen should be considered for the establishment of global quality criteria.

Effect of dietary supplementation or cessation of magnesium-based alkalizers on milk fat output in dairy cows under milk fat depression conditions

We aimed to evaluate the effects of dietary supplementation with magnesium oxide and calcium-magnesium dolomite on milk fat synthesis and milk fatty acid profile or persistency in milk fat synthesis after their cessation in dairy cows under milk fat depression conditions. Twenty-four multiparous dairy cows in early lactation (mean ± standard deviation; 112 ± 14 d in milk) were used in a randomized complete block design. Milk fat depression was induced in all cows for 10 d by feeding a diet containing 35.2% starch, 28.7% neutral detergent fiber, and 4.8% total fatty acid (dry matter). The experiment was conducted in 2 periods. During the Mg-supplementation period (d 1-20), cows were randomly assigned to (1) the milk fat depression diet used during the induction phase (control; n = 8), (2) the control diet plus 0.4% magnesium oxide (MG; n = 8), or (3) the control diet plus 0.8% calcium-magnesium dolomite (CMC; n = 8). Compared with the control group, feeding the magnesium-supplemented diets increased milk fat concentration and yield by 12% within 4 d. During the 20-d Mg-supplementation period, both the MG and CMC diets increased milk fat concentration and yield, as well as 3.5% fat-corrected milk and energy-corrected milk yield, without affecting dry matter intake, milk yield, and milk protein and lactose concentrations. In the Mg-cessation period (d 21-30), all cows received the control diet, which resulted in a greater milk fat concentration and yield in the cows that had already received the MG and CMC diets in the Mg-supplementation period. Whereas, milk fat concentration and yield remained high after discontinuation of the magnesium-containing alkalizer until d 27. The difference in milk fat synthesis was associated with lower trans-10 C18:1 (-22%) and higher trans-11 C18:1 (+12.5%) concentrations in milk during the Mg-supplementation period. Furthermore, it was evident that within 2 d of supplementation, the trans-10:trans-11 ratio was lower in MG and CMC cows compared with cows receiving the control. This suggested that the effect of magnesium-based alkalizers on milk fat synthesis was mediated via a shift in ruminal biohydrogenation of cis-9,cis-12 C18:2 in the rumen. In conclusion, abrupt addition of magnesium oxide and calcium-magnesium dolomite increased milk fat synthesis, which persisted for 7 d after cessation of magnesium-based alkalizers. A similar ability to recover milk fat synthesis and normal fatty acid biohydrogenation pathways was observed for magnesium oxide and calcium-magnesium dolomite.

Fennel and Ginger Improved Nutrient Digestibility and Milk Yield and Quality in Early Lactating Egyptian Buffaloes

Abstract The supplementation with herbal and medicinal plants to animals showed positive effects on feed digestion, performance and animal’s health. Fifteen multiparous Egyptian buffaloes (537 ± 18.1 kg body weight), 7 days after parturition, were randomly assigned to 3 treatments in a quintupled 3 × 3 Latin square design in a 63-day experiment. Each experimental period lasted 21 days (15 days of adaptation + 7 days for measurements and samples collection). Buffaloes were assigned according to their previous milk production, weight and parity to study the effect of fennel (Foeniculum vulgare) or ginger (Zingiber officinale) supplementation on feed utilization and lactational performance. Buffaloes were fed a basal diet of concentrates, berseem clover and rice straw in a ratio of 60:30:10 dry matter (DM) basis. The first group was fed the basal diet with no additive as the control treatment, while other buffaloes were fed on the basal diet supplemented with 75 g fennel or ginger/buffalo daily. Additives supplementation did not affect feed intake; however, fennel followed by ginger improved (P&lt;0.05) dry matter, organic matter, crude protein and neutral detergent fiber digestibilities compared to the control. Without affecting blood chemistry, fennel and ginger supplementation improved (P&lt;0.05) production of milk and energy corrected milk, fat concentration and milk energy content and output. Fennel followed by ginger decreased the somatic cell count (P=0.035) compared with the control. Fennel and ginger improved feed efficiency (P&lt;0.05) compared with the control. Fennel increased the proportion of milk trans-10, cis-12 C18:2 (P=0.028), total conjugated linoleic acid without affecting other fatty acids. It is concluded that fennel or ginger at 75 g/buffalo/d improved nutrient digestibility and milk production of lactating buffaloes. Fennel improved milk nutritive value more than ginger.