scholarly journals Buffering Agent via Insulin-Mediated Activation of PI3K/AKT Signaling Pathway to Regulate Lipid Metabolism in Lactating Goats

2018 ◽  
pp. 753-764 ◽  
Author(s):  
L. LI ◽  
M. L. HE ◽  
K. WANG ◽  
Y. S. ZHANG
Keyword(s):  
Fatty Acid ◽  
Signaling Pathway ◽  
Milk Fat ◽  
Rumen Fluid ◽  
Plasma Concentrations ◽  
Fatty Acid Synthetase ◽  
Nonesterified Fatty Acid ◽  
Lactating Goats ◽  
Buffering Agent ◽  
Agent Group

Ruminants are often fed a high-concentrate (HC) diet to meet lactating demands, yet long-term concentrate feeding induces subacute ruminal acidosis (SARA) and leads to a decrease in milk fat. Buffering agent could enhance the acid base buffer capacity and has been used to prevent ruminant rumen SARA and improve the content of milk fat. Therefore, we tested whether a buffering agent increases lipid anabolism in the livers of goats and influences of milk fat synthesis. Twelve Saanen-lactating goats were randomly assigned to two groups: one group received a HC diet (Concentrate: Forage=60:40, Control) and the other group received the same diet with a buffering agent added (10 g sodium butyrate, C4H7NaO2; 10 g sodium bicarbonate, NaHCO3; BG) over a 20-week experimental period. Overall, milk fat increase (4.25±0.08 vs. 3.24±0.10; P<0.05), and lipopolysaccharide levels in the jugular (1.82±0.14 vs. 3.76±0.33) and rumen fluid (23,340±134 vs. 42,550±136) decreased in the buffering agent group (P<0.05). Liver consumption and release of nonesterified fatty acid (NEFA) into the bloodstream increased (P<0.05). Phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT) and ribosomal protein S6 kinase (p70S6K) up-regulated significantly in the livers of the buffering agent group (P<0.05). It also up-regulated expression of the transcription factor sterol regulatory element binding protein-1c (SREBP-1c) and its downstream targets involved in fatty acid synthetic, including fatty acid synthetase (FAS), stearoyl-CoA desaturase (SCD-1) and acetyl-CoA carboxylase 1 (ACC1) (P<0.05). The BG diet increased insulin levels in blood (19.43±0.18 vs. 13.81±0.10, P<0.05), and insulin receptor was likewise elevated in the liver (P<0.05). Cumulatively, the BG diet increased plasma concentrations of NEFA by INS-PI3K/AKT-SREBP-1c signaling pathway promoting their synthesis in the liver. The increased NEFA concentration in the blood during BG feeding may explain the up-regulated in the milk fat of lactating goats.

Milk production, milk composition, and reproductive function of dairy cows fed different fats

2001 ◽  
Vol 81 (2) ◽  
pp. 263-271 ◽  
Author(s):  
H. V. Petit ◽  
R. J. Dewhurst ◽  
J. G. Proulx ◽  
M. Khalid ◽  
W. Haresign ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Milk Production ◽  
Milk Yield ◽  
Milk Fat ◽  
Plasma Concentrations ◽  
Reproductive Function ◽  
Fat Percentage ◽  
Blood Concentrations ◽  
Flaxseed Meal ◽  
Fat Supplements

Thirty-five non-gestating multiparous Holstein cows averaging 571 kg of BW (SE = 8) were allotted at 9 wk postpartum to one of two dietary fat supplements based on either Megalac® (Volac Ltd., Roston, Hertfordshire, UK) and solvent extracted flaxseed meal (MEGA) or whole flaxseed treated with formaldehyde (FLAX) to determine the effects on milk production and composition, follicular development, gestation rate, and fatty acid (FA) composition of blood. Cows were fed a total mixed diet based on ryegrass silage and fat supplements for ad libitum intake. The experiment was carried out between weeks 9 and 19 of lactation. Dry matter (DM) intake and change in body weight were similar for cows fed MEGA and FLAX. Milk production was higher for cows fed MEGA than for those fed FLAX (19.8 vs. 18.6 kg d–1) as was 4% fat-corrected milk yield (22.9 vs. 20.2 kg d–1). Increased fat mobilization could have contributed to increased milk yield when cows were fed MEGA compared with when they were fed FLAX as plasma concentrations of non-esterified FA and cholesterol increased more from weeks 9 to 19 of lactation for cows fed MEGA. Milk fat percentage tended (P = 0.06) to be greater for cows fed MEGA (4.62%) compared with those fed FLAX (4.37%). Milk protein percentage was higher for cows fed FLAX (3.09%) than for those fed MEGA (2.95%), indicating that formaldehyde protection of flaxseed was adequate to partly prevent ruminal degradability of protein in the seed. Milk fatty acid concentrations of C8:0, C10:0, C12:0, C14:0, C14:1, C18:0, C18:3, and C20:5 were higher for cows fed FLAX than for those fed MEGA while the inverse was observed for C16:0, C16:1, C18:1, and C18:2. Cows fed FLAX had lower blood concentrations of C16:0 than those fed MEGA. There was a significant interaction (P < 0.05) between week and diet for C18:0 and C18:2 with a decrease in C18:0 blood concentration for cows fed MEGA and an increase for those fed FLAX between weeks 9 and 19, while the inverse was observed for C18:2. Blood concentrations of C18:1 were similar for both treatments. Conception rate was significantly lower for cows fed MEGA (50.0%) compared to those fed FLAX (87.5%). Diet had no effect on the size of the largest and second largest follicles, or on the difference between the diameter of the largest and second largest follicles. The number of class 1 (1.09 vs. 0.86), 2 (1.33 vs. 0.86), and 3 (1.28 vs. 0.98) follicles was similar for MEGA and FLAX although the total number (3.70 vs. 2.70) of follicles tended (P = 0.09) to be greater for cows fed MEGA than for those fed FLAX. These data suggest that dietary FA have an effect on gestation rate, but this could not be explained by differences in follicle dynamics or number. However, additional trials with greater numbers of animals are needed to confirm the reproductive results. Key words: Dairy, flaxseed, milk production, reproduction, fatty acids

scholarly journals Changes in milk fatty acid composition of goats during lactation in a semi-intensive production system

2009 ◽  
Vol 52 (6) ◽  
pp. 627-636 ◽  
Author(s):  
C. Ataşoğlu ◽  
Ç. Uysal-Pala ◽  
Y. Karagül-Yüceer
Keyword(s):  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Acid Composition ◽  
Production System ◽  
Milk Fat ◽  
Sampling Period ◽  
Milk Fatty Acid ◽  
Entire Study ◽  
Intensive Production ◽  
Lactating Goats

Abstract. This study aimed at investigating changes in the fatty acid (FA) profile and conjugated linoleic acid (CLA) concentration of milk fat during lactation from goats managed in a semi-intensive production system, which consisted of grazing on a woody and herbaceous pasture with the supplementation of mixed concentrate and vetch hay. A total of 21 lactating goats were used. Milk samples were collected at different periods (25 April, 29 June, 25 August and 4 October) during lactation and analysed for their chemical composition and FA profile. The most abundant FA in the milk fat of goats was palmitic (C16:0) acid, followed by oleic (C18:1 n-9), stearic (C18:0), capric (C10:0) and myristic (C14:0) acids. These acids accounted for about 88 % of the total milk FA of goats in all sampling periods. The two medium chain FA; capric (P=0.0001) and lauric (C12:0; P=0.0014) acid were affected by the sampling period, whereas myristic (P=0.4469) and palmitic (P=0.4418) acids did not change. Stearic (P=0.0128), oleic (P=0.0001), linoleic (C18:2; P=0.0088) and linolenic (C18:3; P=0.0001) acids also exhibited significant variations between the sampling periods. However, the CLA (C18:2 c9, t11 and C18:2 t10, c12) contents of milk fat did not change during the entire study regardless of the sampling period (P=0.2448). Milk fatty acid composition of goats, which meet a major part of their nutrient requirements through grazing or browsing in a natural pasture, shows a seasonal variation with milk fat in summer representing a better fatty acid profile for product quality.

scholarly journals Quantitative aspects of fatty acid biohydrogenation, absorption and transfer into milk fat in the lactating goat, with special reference to the cis- and trans-isomers of octadecenoate and linoleate

1972 ◽  
Vol 130 (2) ◽  
pp. 607-617 ◽  
Author(s):  
R. Bickerstaffe ◽  
D. E. Noakes ◽  
E. F. Annison
Keyword(s):  
Small Intestine ◽  
Fatty Acid ◽  
Milk Fat ◽  
Complex Mixture ◽  
Quantitative Information ◽  
Trans Isomers ◽  
Cis And Trans Isomers ◽  
Lactating Goats ◽  
Cis And Trans ◽  
Ruminal Biohydrogenation

1. Surgically prepared lactating goats were used to obtain quantitative information on the biohydrogenation and absorption of dietary fat, and on the mammary uptake and transfer into milk fat of the complex mixture of cis- and trans-isomers of octadecenoate that arise during ruminal biohydrogenation. 2. About 90% of dietary linolenate, linoleate and oleate was hydrogenated in the rumen, and the availability to the animals of the essential fatty acid, linoleate, represented only 0.5–1.5% of the total dietary energy. 3. The intra-ruminal administration of 14C-labelled linolenate and linoleate showed that these acids were not absorbed from the rumen, in agreement with previous work. 4. No selectivity was observed in the metabolism of the geometrical and positional isomers of octadecenoate: their rates of absorption from the small intestine, transfer into lymph, uptake by the mammary gland and appearance in milk fat were similar. 5. The desaturase activity of intestinal epithelium was demonstrated by the appearance in lymph of [1-14C]oleate after the addition of [1-14C]stearate to the small intestine.

Effect of condensed tannins inLotus corniculatusupon lactation performance in ewes

1996 ◽  
Vol 126 (3) ◽  
pp. 353-362 ◽  
Author(s):  
Y. Wang ◽  
G. B. Douglas ◽  
G. C. Waghorn ◽  
T. N. Barry ◽  
A. G. Foote
Keyword(s):  
Growth Hormone ◽  
Milk Production ◽  
Milk Yield ◽  
Milk Fat ◽  
Condensed Tannins ◽  
Rumen Fluid ◽  
Plasma Concentrations ◽  
Lactation Performance ◽  
Plasma Urea ◽  
Secretion Rates

SUMMARYA grazing experiment was conducted for 8 weeks in the spring/summer of 1993 at Palmerston North, New Zealand, to study the effects of condensed tannins (CT) inLotus corniculatus(birdsfoot trefoil cv. Grasslands Goldie) upon the lactation performance of ewes rearing twin lambs. Effects of CT were evaluated by studying the responses of ewes to twice daily oral supplementation with polyethylene glycol (PEG; MW 3500), which binds and inactivates CT. A rotational grazing system with restricted feed allowance was used. Measurements were made of pre- and post-grazing herbage mass, the composition of the feed on offer and diet selected, voluntary feed intake (VF1), milk yield and composition, liveweight gain and wool production. The concentration of metabolites in rumen fluid and in blood plasma was also measured. Lotus contained 35–5 g total nitrogen and 44–5 g total CT/kg dry matter in the diet selected, with anin vitrodigestibility of 73%. At peak lactation (weeks 3 and 4) milk yield and composition were similar for control (CT-acting) and PEG-supplemented (CTinactivated) ewes but, as lactation progressed, the decline in milk production and in the secretion rates of protein and lactose were less for control than for PEG-supplemented ewes. In mid and late lactation (weeks 6–11), control ewes secreted more milk (21 %), more milk protein (14%) and more lactose (12%) than PEG-supplemented ewes. Milk fat percentage was lower for control than for PEG-supplemented ewes, but secretion rates of fat were similar for the two groups. VFI, liveweight gain and wool growth were similar for both groups. Plasma urea and glucose concentrations were lower for control than for PEG-supplemented ewes, but concentrations of non-esterified fatty acids (NEFA), growth hormone and insulin were similar for the two groups. The concentrations of ammonia and molar proportions ofiso-butyric,iso-andn-valeric acids in rumen fluid were lower for control than for PEG-supplemented ewes; molar proportions of acetic, propionic and H-butyric acids were similar for the two groups. It was concluded that for ewes rearing twin lambs grazingL. corniculatus, the action of CT increased milk yield and the secretion rates of protein and lactose without affecting VFI, thereby increasing the efficiency of milk production. The increased milk production did not appear to be mediated by effects on plasma concentrations of growth hormone or insulin.

scholarly journals High Rumen-Degradable Starch Diet Promotes Hepatic Lipolysis and Disrupts Enterohepatic Circulation of Bile Acids in Dairy Goats

2020 ◽  
Vol 150 (10) ◽  
pp. 2755-2763
Author(s):  
Jing Shen ◽  
Xiaoying Han ◽  
Lixin Zheng ◽  
Shimin Liu ◽  
Chunjia Jin ◽  
...  
Keyword(s):  
Protein Expression ◽  
Bile Acids ◽  
Milk Fat ◽  
Enterohepatic Circulation ◽  
Rumen Fluid ◽  
Liver Protein ◽  
Dairy Goats ◽  
Linear Discriminant ◽  
Lactating Goats ◽  
Carnitine Palmitoyltransferase 1

ABSTRACT Background High rumen-degradable starch (RDS) diets decrease milk fat. The increase of LPS in plasma associated with increased RDS impairs liver function, immune response and lipid metabolism, which depress the precursors for milk fat. Objective This study investigated the mechanism of depression of milk fat precursors in the liver and small intestine of dairy goats fed different RDS diets. Method Eighteen Guanzhong lactating goats (second lactation, 45.8 ± 1.54 kg) and 6 ruminally cannulated dairy goats (aged 2–3 y, 54.0 ± 2.40 kg) were fed 3 different diets with low dietary RDS concentrations of 20.52% (LRDS), medium RDS of 22.15% (MRDS), and high RDS of 24.88% (HRDS) for 36 and 21 d, respectively, in experiments 1 and 2. The liver metabolites and jejunal microbiota in experiment 1 and LPS concentrations in rumen fluid and plasma in experiment 2 were measured. One-way ANOVA was used to analyze the biochemical parameters and mRNA or protein expression. The MIXED procedure was used to analyze LPS concentrations. Results In experiment 1, the HRDS diet showed increased activity of alkaline phosphatase (27.4 to 41.4 U/L) in plasma (P &lt; 0.05) compared with LRDS treatment. The HRDS diet significantly increased the hepatic concentrations of l-carnitine (129%), l-palmitoylcarnitine (306%), taurochenodeoxycholate (856%), and taurodeoxycholic acid (588%) in liver (variable importance in the projection &gt; 1, P &lt; 0.10) compared with the LRDS treatment. Goats fed the HRDS diet had 33.6% greater liver protein expression of carnitine palmitoyltransferase-1 (P &lt; 0.05), and greater relative abundance of Firmicutes and Ruminococcus 2 in the jejunal content (linear discriminant analysis &gt; 2.0, P &lt; 0.05) than did goats fed LRDS diet. In experiment 2, goats fed the HRDS diet had greater LPS concentrations in rumen fluid (7.57 to 13.6 kEU/mL) and plasma (0.037 to 0.179 EU/mL) (P &lt; 0.05) than did goats fed LRDS diet. Conclusions Feeding the HRDS diet promoted hepatic lipid β-oxidation and disrupted phospholipid and bile acids metabolisms in liver, thereby reducing the supply of lipogenic precursors to the mammary gland in dairy goats.

scholarly journals Relations between plasma non-esterified fatty acid metabolism and body fat mobilization in primiparous lactating goats

1989 ◽  
Vol 62 (1) ◽  
pp. 51-61 ◽  
Author(s):  
F. R. Dunshea ◽  
A. W. Bell ◽  
T. E. Trigg
Keyword(s):  
Fatty Acid ◽  
Energy Balance ◽  
Body Fat ◽  
Tritiated Water ◽  
Plasma Concentrations ◽  
Subsequent Stage ◽  
Plasma Nefa ◽  
Entry Rate ◽  
Fat Mobilization ◽  
Lactating Goats

During early lactation ruminants can mobilize considerable amounts of body fat to maintain milk production. The aim of the present study was to evaluate the efficacy of tritiated water (TOH) and non-esterified fatty acid (NEFA) kinetics as means of monitoring adipose tissue fat mobilization in lactating goats. Body fat, as estimated by a two-pool model of TOH kinetics, and NEFA entry rate were measured in four primiparous goats at days 11, 37 and 72 post partum. Estimated body fat decreased by an average of 64 g/d between days 11 and 37 of lactation, tending to increase between days 37 and 72. Plasma NEFA concentrations and NEFA entry rate decreased as lactation advanced, being significantly lower at day 72 than at day 11 of lactation. Both plasma concentrations of NEFA and NEFA entry rate were negatively correlated with calculated energy balance. Plasma NEFA concentrations and NEFA entry rate at days 11 and 37 of lactation were positively related to average body fat losses over the subsequent stage of lactation. These results demonstrate that NEFA kinetics reflect fat mobilization in primiparous lactating goats, particularly during negative energy balance.

scholarly journals Blood metabolites and fatty acid composition of milk and cheese from ewes fed oilseeds

2006 ◽  
Vol 86 (4) ◽  
pp. 547-556 ◽  
Author(s):  
R. H. Zhang ◽  
A. F. Mustafa ◽  
X. Zhao
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Milk Yield ◽  
Milk Fat ◽  
Unsaturated Fatty Acids ◽  
Control Diet ◽  
Plasma Concentrations ◽  
Plasma Metabolites ◽  
Blood Metabolites ◽  
Fat Percentage

Sixteen lactating Dorset ewes were used in a completely randomized design to determine the effects of oilseed supplementation on milk yield and composition, blood metabolites, cheese yield and composition and fatty acid profile of milk and cheese. Four iso-nitrogenous diets were formulated: a control diet (CT) with no oilseed supplementation, a flaxseed supplemented diet (FS), a sunflower seed supplemented diet (SF), and a canola seed supplemented diet (CS). Oilseed-supplemented diets were formulated to contain 7% fatty acids. Feeding oilseeds had no effect on dry matter intake. Milk yield was similar for ewes fed CT, FS and SF and was higher (P < 0.05) than that of ewes fed CS. Ewes fed oilseed-supplemented diets produced milk with higher (P < 0.05) protein and total solid percentages than those fed CT. However, milk fat percentage was only higher (P < 0.05) in the milk of ewes fed FS and SF relative to those fed CT. Actual cheese yield was higher (P < 0.05) from milk of ewes fed oilseed-supplemented diets relative to those fed CT. However, cheese composition was not affected by dietary treatments. Plasma concentrations of fatty acids and cholesterol were increased (P < 0.05) while plasma concentration of β-hydroxybutyrate (βHBA) was decreased (P < 0.05) by oilseed supplementation. However, plasma concentrations of glucose and mammary extraction rate of plasma metabolites were not influenced by oilseed feeding. Oilseed supplementation increased (P < 0.05) concentrations of unsaturated fatty acids in milk fat. The order of increase was SF > FS > CS. Feeding SF, FS and CS increased (P < 0.05) conjugated linoleic acid (CLA) concentration in milk by 83.5, 39.2 and 16.5%, respectively. Concentration of linolenic acid in milk was only increased (P < 0.05) by feeding FS. Changes in milk fatty acid profiles were reflected in the cheese. Key words: Ewes, oilseeds, milk, cheese, fatty acids

Evaluation of a compartmental model to describe non-esterified fatty acid kinetics in Holstein dairy cows

2007 ◽  
Vol 74 (4) ◽  
pp. 430-437 ◽  
Author(s):  
Peter J Moate ◽  
John R Roche ◽  
Lucia M Chagas ◽  
Raymond C Boston
Keyword(s):  
Fatty Acid ◽  
Dairy Cows ◽  
Milk Fat ◽  
Compartmental Model ◽  
General Pattern ◽  
Plasma Concentrations ◽  
Latency Period ◽  
Whole Body ◽  
Intravenous Glucose ◽  
Lactating Dairy Cows

The dynamics of non-esterified fatty acid (NEFA) metabolism in lactating dairy cows requires quantification if we are to understand how dietary treatments and disease influence changes in body condition (adipose reserves) and the production of milk fat. Recently, Thomaseth & Pavan (2003) presented a compartmental model (Thomaseth model), which employs the pattern of plasma insulin concentrations in humans to predict the dynamic changes that occur in the plasma concentrations of glucose and NEFA during an intravenous glucose tolerance test (IVGTT). The Thomaseth model, or at least a similar model, could have potential application to the field of energy metabolism in ruminants because it would enable the estimation of parameters that describe the rates of whole body disposition of glucose, and the production and utilization of NEFA. In this study we investigated the suitability of the Thomaseth model to describe NEFA and glucose kinetics in 10 lactating Holstein-Friesian cows given a standard IVGTT in early lactation. The Thomaseth model described the general pattern of the NEFA response and, in particular, described the downward-slope and nadir in NEFA concentrations reasonably well. However, it failed to describe the initial latency period (the period before NEFA concentrations decline precipitously), and it could not describe terminal ‘rebound’ plateau in NEFA concentration. Because of these inherent problems, the parameters of the Thomaseth model cannot be considered to provide accurate estimates of rates of NEFA production or utilization. It is concluded that the Thomaseth model is not suitable for describing NEFA kinetics in lactating dairy cows.

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