Cobalt reduces the Δ9‐desaturase index of sow milk Karlengen, I. J; Harstad, O. M; Kjos, N. P ...
Journal of animal physiology and animal nutrition,
October 2011, Letnik:
95, Številka:
5
Journal Article
Recenzirano
The main objective of this study was to examine if cobalt (Co) reduces Δ9‐desaturase indices in milk and blood lipids in sows. The experimental design consisted of a repeated measurement consisting ...of a pre‐treatment period of a minimum of 9 days, a treatment period of 5 days and a post‐treatment period of 6 days. Experimental animals consisted of 10 lactating sows; five sows had an intramuscular injection of 59 mg Co diluted in 5 ml 0.9% saline solution twice a day, whereas the other five had an intramuscular injection of 5 ml 0.9% saline solution twice a day as a control. Milk Δ9‐desaturase indices for cis‐9 18:1, cis‐9 16:1 and cis‐9 14:1 were significantly reduced (p < 0.0001) as a result of the Co‐treatment, contrasting with the plasma Δ9‐desaturase indices, which were unaffected. Potential mechanisms explaining how Co might reduce milk Δ9‐desaturase indices are discussed. Moreover, the toxicological level of Co and potential implications of using Co‐ethylenediaminetetraacetic acid as a liquid marker in digestibility experiments are addressed.
Dairy milk samples from 37 milk tours in 15 areas of Norway were collected during indoor feeding or on pasture in 2008 and analyzed with respect to 6 major elements (Ca, P, K, S, Na, Mg) and 28 trace ...elements (As, Ba, Be, Bi, Cd, Ce, Co, Cr, Cs, Cu, Dy, Fe, I, La, Li, Mn, Mo, Nd, Pb, Rb, Sb, Se, Sm, Sr, V, Y, Yb and Zn). Surprisingly, the least-square means of major and trace elements in milk did not vary much from one region to another. The concentration levels of iodine, copper, manganese and lithium in milk from the northern region were higher compared with milk from other regions. Milk from the south was enriched with respect to selenium, yttrium, cerium and bismuth, while milk from the western region was enriched with respect to rubidium.
The objective of this study was to determine the impact of ruminal pH on methane (CH^sub 4^) emission from beef cattle. Ruminal pH and CH^sub 4^ data were generated in 2 experiments using 16 beef ...heifers offered high-forage (55% barley silage) or high-grain (92% concentrate; DM basis) diets. Both experiments were designed as a replicated 4 . 4 Latin square with 4 periods and 4 dietary treatments. Methane was measured over 4 consecutive days using open-circuit respiratory chambers with each chamber housing 2 heifers. The ruminal pH of individual heifers was measured using indwelling pH loggers. The mean ruminal pH and CH^sub 4^ emission (g/h) of 2 heifers in every chamber were summarized in 30-min blocks. Even though rumen methanogens have been described to be inhibited by a pH < 6.0 in vitro, in vivo CH^sub 4^- production rates (g/h) did not decrease when ruminal pH declined to threshold levels for subacute (5.2 . pH < 5.5) or acute ruminal acidosis (pH < 5.2; P > 0.05). Daily mean CH4 emission (g/d) and ruminal pH were only mildly correlated (r2 = 0.27; P < 0.05), suggesting that additional factors, such as increased propionate formation or passage rate, account for the lower CH^sub 4^ emissions from cattle fed high-grain as compared to high-forage diets. Lowering ruminal pH alone is, therefore, not an effective CH^sub 4^-mitigation strategy. Mechanisms permitting methanogens to survive episodes of low-ruminal pH might include changes in community structure toward more pH-tolerant strains or sequestration into microenvironments within biofilms or protozoa where methanogens are protected from low pH.
Controlling the time of harvest to affect grass maturity for silage was evaluated as a methane (CH₄) mitigation strategy in a batch culture in vitro with ruminal fluid as inoculum and silage from a ...mixed timothy (Phleum pretense)-meadow fescue (Festuca pratensis) stand. The stand was cut in May (early maturity EM; first cutting), June (late maturity LM; first cutting), and August (mid-maturity MM; third cutting). Disappearance of neutral detergent fiber (NDF) (EM: 0.58; MM: 0.50; LM: 0.45) and ADF (EM: 0.57; MM: 0.49; LM: 0.45) after 48 h was greater for EM compared to MM and LM, with no difference between the latter two. With advancing maturity, total gas (EM: 166.6; MM: 149.7; LM: 119.3 mL), CH₄ production (EM: 21.4; MM: 17.6; LM: 14.8 mL), and methane production per g NDF digested decreased at 48 h (EM: 120; MM: 92; LM: 74 mL/g NDF digested). Ensiling less mature grass resulted in more CH₄ per unit of NDF digested.
Methane production from wheat- or corn-based dried distillers' grains with solubles (CDDGS, WDDGS) was compared in vitro. Wheat DDGS (49 g fat/kg dry matter DM) or CDDGS (115 g fat/kg DM) partially ...or completely replaced whole-crop barley silage at 200, 400, 600, 800 or 1000 g/kg DM. Production of CH₄ increased linearly and quadraticly (p<0.01) with increasing levels of CDDGS. Cumulative CH₄ production at 24 h was higher (p<0.05) for WDDGS (12.0±0.5 mg/g DM) than CDDGS up to 800 g/kg DM. Molar proportions of propionate in incubation fluid were higher (p<0.05) for CDDG than for WDDGS at 200, 400 and 600 g/kg DM, respectively. In vitro CH₄ production (mg CH₄/g DM; mg CH₄/g digested DM DMD) was lower for CDDGS than WDDGS up to 800 g/kg substrate DM. The higher residual oil content in CDDGS compared to WDDGS likely elicited this response.
We studied the kinetics of lysine, methionine, and threonine in six high-yielding dairy cows at peak lactation (stage 1) and 6 mo later (stage 2). The cows were fitted with cannulas in the rumen and ...duodenum and were automatically fed every 4th h. The three amino acids (AA) were administered intraruminally in mixtures at dosages of 100, 200, 300, and 400 mmol of each, together with polyethylene glycol (PEG) as a liquid marker. Mean rumen liquid pools at stages 1 and 2 were not significantly different. The mean liquid outflow decreased from 13.6 to 9.5 L/ h, and there was a significant linear increase in the liquid outflow with increasing dosages of AA. No significant interaction was found between feeding levels and AA dosages on rates of apparent degradation and rumen escape values. Expressed as percentages of the dosage, all three AA studied showed a significant linear decrease in degradation and a significant increase in rumen escape values with increasing dosage. At the feeding levels in stages 1 and 2, the highest relative degradation rates (percentage of dosage) were observed for threonine. The relative degradation rate of methionine was significantly lower than of lysine at the high feeding level but significantly higher at the low feeding level. The mean rumen escape values of threonine, methionine, and lysine across dosages and feeding levels were 16.7, 22.1, and 20.5%, respectively. The flow of the administered AA into the duodenum during an 8-h period after administration increased with increasing dosages, with peak concentrations after 1 h. Thus, the amounts of rumen escape of the three AA were considerable at all dosages, even when the AA were administered in unprotected form
Cow milk is a natural source of the cis 9, trans 11 isomer of conjugated linoleic acid (c9,t11-CLA) and trans vaccenic acid (VA). These fatty acids may be considered as functional foods, and the ...concentration in milk can be increased by e.g. sunflower oil supplementation to the dairy cow feed. The objective of this study was to compare the effects of regular butter with a special butter naturally enriched in c9,t11-CLA and VA on plasma lipids in female growing pigs. The experimental period lasted for three weeks and the two diets provided daily either 5.0 g c9,t11-CLA plus 15.1 g VA or 1.3 g c9,t11-CLA plus 3.6 g VA.
The serum concentrations of c9,t11-CLA, VA and alpha-linolenic acid were increased and myristic (14:0) and palmitic acid (16:0) were reduced in the pigs fed the CLA+VA-rich butter-diet compared to regular butter, but no differences in plasma concentrations of triacylglycerol, cholesterol, HDL-cholesterol, LDL-cholesterol, LDL particle size distribution or total cholesterol/HDL cholesterol were observed among the two dietary treatment groups.
Growing pigs fed diets containing butter naturally enriched in about 20 g c9,t11-CLA plus VA daily for three weeks, had increased serum concentrations of alpha-linolenic acid and decreased myristic and palmitic acid compared to pigs fed regular butter, implying a potential benefit of the CLA+VA butter on serum fatty acid composition. Butter enriched in CLA+VA does not appear to have significant effect on the plasma lipoprotein profile in pigs.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Meale, S. J., Ding, S., He, M. L., Dugan, M. E. R., Ribeiro Jr. G. O., Alazzeh, A. Y., Holo, H., Harstad, O. M., McAllister, T. A. and Chaves, A. V. 2014. Effect of Propionibacterium freudenreichii ...on ruminal fermentation patterns, methane production and lipid biohydrogenation of beef finishing diets containing flaxseed oil in a rumen simulation technique. Can. J. Anim. Sci. 94: 685–695. The objectives of this study were to examine the effects of Propionibacterium freudenreichii (strain T54; PB) and flaxseed oil (FO) in a total mixed ration on ruminal fermentation, CH
4
production and fatty acid biohydrogenation in two artificial rumens (RUSITEC). The experiment consisted of 8 d of adaptation and 12 d of sample collection with four replicate fermenters per treatment. Treatments were: (1) CON; (2) PB; (3) FO (60 g kg
−1
DM with autoclaved PB); (4) FOPB (60 g kg
−1
DM with PB). Disappearance of DM (g kg
−1
DM) and gas production (mL g
−1
DM) were not affected by treatment (P>0.05). Inclusion of FOPB increased (P=0.01) total volatile fatty acid (VFA) production (mmol d
−1
), compared with CON and PB. The acetate:propionate ratio was reduced (P<0.001) in all treatments, compared with CON. Methane production (mL g
−1
DM or mL g
−1
DMD) was lowest (P<0.001) with PB (27.1%); however, FO (14.3%) and FOPB (19.3%) also reduced CH
4
compared with CON. Fatty acid profiles for PB were similar (P>0.05) to CON for most fatty acids. Concentrations of 18:3n-3 were greater (P<0.001) in FO and FOPB in both digesta and effluent, compared with CON. Propionibacterium freudenreichii had very little effect on ruminal biohydrogenation, but reduced CH
4
production under the current conditions as a result of increasing propionate production.
Hünerberg, M., McGinn, S. M., Beauchemin, K. A., Okine, E. K., Harstad, O. M. and McAllister, T. A. 2013. Effect of dried distillers' grains with solubles on enteric methane emissions and nitrogen ...excretion from finishing beef cattle. Can. J. Anim. Sci. 93: 373-385. The objective of this study was to examine the impact of corn- or wheat-based dried distillers'grains with solubles (CDDGS, WDDGS) on enteric methane (CH4) emissions from finishing beef cattle, and to determine if any observed reductions were a result of the fat content of CDDGS. A second objective was to compare the effect of CDDGS or WDDGS on N excretion. The experiment was designed as replicated 4×4 Latin square with 28-d periods using 16 ruminally fistulated crossbred heifers. The control diet contained 87% barley grain, 8% barley silage and 5% supplement (dry matter; DM basis). Treatment diets were formulated by replacing 40% DM of barley grain with CDDGS, WDDGS, or corn oil supplemented WDDGS (WDDGS+oil). For the WDDGS+oil diet 6.5% corn oil was added to WDDGS (3.4% fat DM) to achieve a similar fat level as in CDDGS (9.7% DM). All diets were fed as total mixed rations once daily ad libitum. Total collection of urine and faeces was conducted between days 18 and 21. Methane was measured between days 25 and 28 using four identical open circuit respiratory chambers. Compared with WDDGS, feeding CDDGS and WDDGS+oil reduced (P<0.05) CH4 emissions as a percentage of gross energy intake (GEI) from 5.5 to 4.0 and 4.2%, respectively. Feeding CDDGS also reduced (P<0.05) CH4 emissions compared with the control (5.0% of GEI), while WDDGS+oil tended (P=0.08) to elicit a similar response. Methane (% of GEI) between WDDGS and the control did not differ (P=0.29). Excretion of total N was greater (P<0.001) for CDDGS, WDDGS and WDDGS+oil (220, 253, and 265 g d-1) compared with the control (143 g d-1). Although oil appears to be responsible for reducing CH4 emissions when DDGS is included in the diet, increased N excretion requires that a complete life cycle assessment be conducted to assess the full impact of DDGS on greenhouse gas emissions from finishing cattle.
Meale, S. J., Ding, S., He, M. L., Dugan, M. E. R., Ribeiro Jr. G. O., Alazzeh, A. Y., Holo, H., Harstad, O. M., McAllister, T. A. and Chaves, A. V. 2014. Effect of Propionibacterium freudenreichii ...on ruminal fermentation patterns, methane production and lipid biohydrogenation of beef finishing diets containing flaxseed oil in a rumen simulation technique. Can. J. Anim. Sci. 94: 685-695. The objectives of this study were to examine the effects of Propionibacterium freudenreichii (strain T54; PB) and flaxseed oil (FO) in a total mixed ration on ruminal fermentation, CH4 production and fatty acid biohydrogenation in two artificial rumens (RUSITEC). The experiment consisted of 8 d of adaptation and 12 d of sample collection with four replicate fermenters per treatment. Treatments were: (1) CON; (2) PB; (3) FO (60 g kg-1 DM with autoclaved PB); (4) FOPB (60 g kg-1 DM with PB). Disappearance of DM (g kg-1 DM) and gas production (mL g-1 DM) were not affected by treatment (P>0.05). Inclusion of FOPB increased (P=0.01) total volatile fatty acid (VFA) production (mmol d-1), compared with CON and PB. The acetate:propionate ratio was reduced (P<0.001) in all treatments, compared with CON. Methane production (mL g-1 DM or mL g-1 DMD) was lowest (P<0.001) with PB (27.1%); however, FO (14.3%) and FOPB (19.3%) also reduced CH4 compared with CON. Fatty acid profiles for PB were similar (P>0.05) to CON for most fatty acids. Concentrations of 18:3n-3 were greater (P<0.001) in FO and FOPB in both digesta and effluent, compared with CON. Propionibacterium freudenreichii had very little effect on ruminal biohydrogenation, but reduced CH4 production under the current conditions as a result of increasing propionate production.
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