Effects of the palmitic to oleic ratio in the form of calcium salts of fatty acids on the production and digestibility in high-yielding dairy cows.

The form of fat supplements, degree of saturation, and the fatty acid (FA) profile influence the cows' production response. The objective was to determine the effects of supplemental fats in the form of calcium salts of fatty acids (CSFA) with different ratios between palmitic (PA) and oleic (OA) acids on nutrient digestibility and cow performance. Forty-two dairy cows were assigned to 3 groups and fed (for 13 wk) rations that contained 2.2% CSFA (on a dry matter basis) with increasing the PA-to-OA ratio as follows: 1) CS45:35 - 45% PA and 35% OA, 2) CS60:30 - 60% PA and 30% OA, and 3) CS70:20 - 70% PA and 20% OA. Rumen and fecal samples were taken for volatile fatty acids (VFA) and digestibility measurements, respectively. Increasing the PA-to-OA ratio linearly decreased the milk and energy-corrected milk (ECM) yields, whereas a quadratic effect was observed for milk fat concentration (3.55, 3.94, and 3.87% in the CS45:35, CS60:30, and CS70:20 groups, respectively) and fat yield. Dry matter intake (DMI) was highest in the CS60:30 group (33.7 kg/d), and lowest in the CS70:20 group (31.6 kg/d), and a tendency of quadratic effect was observed for calculated energy balance with no difference in body weight gain among the groups. The milk-to-DMI ratio was decreased, and the ratio of ECM-to-DMI tended to decrease when the PA-to-OA ratio increased. The highest apparent total-tract digestibilities of dry matter, organic matter, and protein were observed in the CS60:30 cows, and neutral detergent fiber (NDF) tended to decrease with increasing the PA-to-OA ratio; however, digestibility of the total FA and FA subgroups (16 and 18-carbon FA) were not different among groups. Across treatments, the 18-carbon FA digestibility was higher than the 16-carbon FA digestibility. Under the current study conditions, the CS60:30 cows had the highest fat concentration and fat yield, energy output in milk, DMI, and digestibility of DM, OM, and protein. However, further research is required to fine-tune the optimal FA ratio in supplemental fat sources to maximize production and efficiency under various conditions, such as production level, stage of lactation, and diet composition.

The form more than the fatty acid profile of fat supplements influences digestibility but not necessarily the production performance of dairy cows.

The form of a lipid supplement, its degree of saturation, and its fatty acid (FA) profile greatly influence digestibility and cow productive response. The objective in this study was to examine the effect of fat supplements that differ in their form or FA profile on nutrient digestibility and cow performance. Forty-two mid-lactation cows (128 ± 53 d) were assigned to 3 treatment groups according to milk yield, days in milk, and body weight. For 13 wk, the cows were fed rations that contained (on a dry matter basis) (1) 2.4% of calcium salts of fatty acids (CSFA) consisting of 45% palmitic acid (PA) and 35% oleic acid (OA; CS45:35); (2) 2.4% of CSFA consisting of 80% PA and 10% OA (CS80:10); or (3) 2.0% of free FA consisting of 80% PA and 10% OA (FF80:10). Rumen samples were taken to measure the ammonia and volatile FA concentrations, and fecal samples were taken to measure the digestibility. Preplanned comparisons were CS45:35 versus CS80:10 to assess 2 CSFA supplements with different FA profiles, and CS80:10 versus FF80:10 to assess similar FA profiles in different forms. Compared with CS45:35, CS80:10 decreased the milk yields, increased the fat percentage, and tended to increase the energy-corrected milk (ECM) yields. The fat percentage of milk was highest in the FF80:10 cows (4.02%), intermediate in the CS80:10 cows (3.89%), and lowest in the CS45:35 cows (3.75%). Compared with CS80:10, FF80:10 increased milk yields (50.1 vs. 49.4 kg/d, respectively), tended to increase fat percentage, and increased 4% fat-corrected milk (4% FCM; 49.1 vs. 47.7 kg/d, respectively) and ECM yields (49.5 vs. 48.2 kg/d, respectively). Treatment had no effect on dry matter intake (DMI), and compared with CS80:10 cows, the calculated energy balance was lower in the FF80:10 cows. The 4% FCM/DMI and ECM/DMI ratios were higher in the FF80:10 group compared with the CS80:10 group. Compared with the CS80:10 cows, the FF80:10 cows had a lower rumen pH, higher propionate, lower acetate/propionate ratio, and higher total VFA. Compared with CS45:35 cows, the apparent total-tract digestibilities of neutral detergent fiber and acid detergent fiber were higher in CS80:10 cows; whereas, the apparent total-tract digestibilities of dry matter, organic matter, protein, neutral detergent fiber, and acid detergent fiber were higher in the CS80:10 cows compared with the FF80:10 cows. Compared with the CS80:10 group, the apparent digestibility of total FA was 13.0 percentage points lower in the FF80:10 cows (79.1 vs. 66.1%, respectively), and similarly, the digestibilities of 16-carbon and 18-carbon FA were lower in the FF80:10 cows than in the CS80:10 cows. In conclusion, the form, more than the FA profile of fat supplements, influenced digestibility. Further, the CSFA supplements were more digestible than the free fatty acids, regardless of the FA profile. However, energy partitioning toward production appeared to be higher in the FF80:10 cows, although the digestibility of nutrients was lower than in the CSFA product with a similar FA profile.

Proteome dataset of peripheral blood mononuclear cells in postpartum dairy cows supplemented with different sources of omega-3 fatty acids.

This article contains raw and processed data related to research published by Kra et al. [1]. There is a scarce knowledge on the proteome of peripheral blood mononuclear cells (PBMC) during the transition period in dairy cows. In human research, proteomics PBMC is used in order to gain insight into inflammatory diseases and syndromes. Dietary fats, and specifically omega-3 (n-3) FA, can moderate the immune fluctuation caused by parturition through improvements of the immune function [2]. Therefore, this study aim was to characterize the changes that may occur in proteome of PBMC during transition, as influenced by different n-3 FA supplementation. Proteomics data of PBMC was obtained from postpartum dairy cows supplemented peripartum with either encapsulated saturated fat (CTL), encapsulated flaxseed oil that is enriched with ALA (α-linolenic acid; FLX) or encapsulated fish oil that is enriched with EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid; FO).The analysis was done by liquid chromatography-mass spectrometry from PBMCs protein extraction. The cells were collected from six cows per treatment during the 1st week postpartum. Quantification of differential abundance between groups was done using MS1 intensity based label-free. Label-free quantitative shotgun proteomics was used for characterization. This novel dataset of proteomics data from PBMC contains 3807 proteins; 44, 42 and 65 were differently abundant (P ≤ 0.05 and FC ± 1.5), in FLX vs. CTL, FO vs. CTL and FLX vs. FO, respectively; these findings are discussed in our recent research article (Kra et al., 2021). The present dataset of PBMC proteome adds new information regarding the effects of n-3 FA on the immune system, while providing reference for PBMC proteome in postpartum dairy cows.

Proteomic analysis of peripheral blood mononuclear cells and inflammatory status in postpartum dairy cows supplemented with different sources of omega-3 fatty acids.

We examined the effects of dietary n-3 fatty acids on the proteome of peripheral blood mononuclear cells (PBMC) in transition dairy cows. Forty-two dry cows were divided into three groups supplemented with: saturated fat (CTL); flaxseed oil (FLX); or fish oil (FO). PBMC were collected from five cows per group at week 1 postpartum for proteomic analysis. The n-3 fatty acid content in plasma and PBMC was higher in FLX and FO than in CTL cows. In PBMC, 3807 proteins were quantified and 44, 42 and 65 were differently abundant in FLX vs. CTL, FO vs. CTL and FLX vs. FO, respectively. In FLX vs. CTL, the abundance of the p65-subunit-of-transcription-factor NF-κB was higher, whereas albumin, C4b-binding protein and complement factor H levels were lower. In FLX vs. FO, complement factors B and H and hemopexin were higher. The top canonical pathway enriched in FLX compared to other groups was acute-phase-response signaling. The percentage of CD25+ blood cells was lower in FLX and FO at 1 week postpartum, and gene expression of NF-κB in white blood cells was lower in FLX than in CTL. Dietary sources of n-3 fatty acids differentially affected the proteome of PBMC, possibly altering the inflammatory status. SIGNIFICANCE: The transition dairy cow experiences a variable degree of systemic subacute inflammation, and proteomics of peripheral blood mononuclear cells (PBMC) may contribute to obtain insight into this process. Omega-3 fatty acids can moderate the immunological effect, and therefore we examined the effects of these fatty acids from flaxseed (FLX) or fish oils (FO) on the proteome of PBMC at week 1 postpartum. More than 3800 proteins were quantified, and in cows supplemented with FLX, enrichment of the acute-phase-signaling and complement systems were apparent in the PBMC compared to CTL and FO PBMC. This information may be useful to further explore the mechanism by which dietary omega-3 fatty acids affect the immune system in postpartum dairy cows.