首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 343 毫秒
1.
Spelt is a covered cereal with large glumellas. In experiment 1, it has been compared in terms of chemical composition with barley, oat and maize. Spelt is characterized by rather low protein and ether extract (EE) contents. The neutral detergent fibre (NDF) content of spelt was slightly higher than that of oat but the acid detergent fibre (ADF) content was lower. Two compound feedstuffs were fed along with hay to six horses used in a cross-over design. Both diets were well appreciated by the horses and there were no significant differences in the apparent digestibility coefficients, except for EE which was significantly higher, when oat was included in the compound feedstuff. In experiment 2, first pressure linseed oil was incorporated at a rate of 8% in a control compound feedstuff, where the barley was partly substituted by the oil. The fat content was 9.6% dry matter (DM) in the linseed oil compound feedstuff and 5.4% in the hay-concentrate ration. The inclusion of linseed oil increased the digestibility of DM, EE and NDF of the diet. There were no effects on the post-prandial concentrations of glucose, triglycerides and non-esterified fatty acids (NEFA) but the insulin concentration was significantly reduced with the linseed oil inclusion. There were significant increases in the plasma concentrations of the total fatty acids, polyunsaturated fatty acids (PUFA), saturated fatty acids (SFA), C18:3 n-3 and C18:2 n-6 and significant reductions in the contents of monounsaturated fatty acids (MUFA), C18:1 n-7 + n-9 and C20:4 n-6. It is concluded that the inclusions of spelt and first pressure linseed oil in compound feed stuff for horse are of interest for modern horse feeding.  相似文献   

2.
The use of n-3 fatty acids is often recommended to manage pruritus. The purpose of this study was to determine the effect of various doses of n-3 fatty acids at different n-6:n-3 ratios on plasma fatty acids, clinical response and inflammatory mediators in pruritic dogs. After baseline assessment, dogs were randomly assigned to receive diets varying in both total n-3 and n-6 fatty acid dose and n-6:n-3 ratio. The total clinical score decreased significantly in all four diet groups after 8 weeks with no difference between groups. Plasma fatty acid changes generally mirrored the fatty acid content of the test diets, although alterations appeared to depend on both the dose of n-3 fatty acids and the n-6:n-3 ratio. In this clinical trial, which controlled dietary intake of fatty acids, n-3 fatty acid supplementation did not appear to have an added benefit on clinical signs over thorough clinical management.  相似文献   

3.
随着消费者健康意识的提高,越来越多的研究关注提高家养动物肉产品中多不饱和脂肪酸(PUFA)含量,尤其是n-3长链脂肪酸和共轭亚油酸(CLA)在羊、牛、猪肉肌内脂中的含量。研究结果表明通过添加鱼油或鱼粉能提高动物肉中n-3长链脂肪酸含量。富含亚麻油酸(LNA)的日粮能提高肉中LNA、二十碳五烯酸(EPA)和二十二碳五烯酸(DPA)水平,但大部分对肌肉中二十二碳六烯酸(DHA)水平没有影响。然而,在日粮中添加鱼油或鱼粉大部分能提高动物肌肉中DHA含量。大部分研究中提高n-3脂肪酸含量的同时n-6脂肪酸含量下降,这主要归因于试验组日粮中n-6脂肪酸降低。这样刚好可以使肉中两者比例更合理,但对多不饱和脂肪酸与饱和脂肪酸比例没什么影响。饲喂反刍动物富含n-3脂肪酸日粮(亚麻籽或加草料)、鱼油或富含LA的浓缩料可提高肌肉中c9t11CLA含量。牛肉、羊肉中c9t11CLA在总脂中含量介于0.2~1.0 g/100 g,不随营养因素提高到更高。相对应的,在单胃动物日粮中添加混合CLA油则显著提高CLA含量。  相似文献   

4.
Beef knuckles (n = 160) were obtained from source-verified cattle finished on 30% wet distillers grains plus solubles enriched with varying levels of alfalfa hay (4 or 8%), corn silage (6 or 12%), or corn stalks (3 or 6%) based on NDF. Proximate analysis, pH, oxidation-reduction potential, fatty acid composition, and sensory analysis were conducted on the rectus femoris muscle to determine if roughage inclusion, in conjunction with wet distillers grains plus solubles and cattle source, affects beef flavor with particular interest in liver-like off-flavor. Proximate analysis, fat content, and oxidation-reduction potential were unaffected (P ge;0.129) by diet or source. For s.c. adipose tissue, cattle from Nebraska (NE) had greater amounts of MUFA (P = 0.048) and unsaturated fatty acids (P = 0.068) but less SFA (P = 0.065) when compared with cattle from South Dakota. Diet affected s.c. adipose tissue levels of 15:0, 17:0, and n-3 fatty acids in which cattle from NE finished on the low corn stalk diet had (P < or =0.050) lower levels. Cattle from NE had (P < or = 0.049) greater i.m. adipose proportions of 13:0 and CLA. Dietary effects (P < or = 0.050) were observed for i.m. adipose tissue proportions of 16:0, 18:1(n-9), 18:2(n-6), 20:4(n-6), 22:5(n-3), MUFA, PUFA, and n-6 fatty acids. Sensory analysis revealed that cattle from NE were (P < or = 0.023) less juicy and had less bloody notes when compared with cattle from South Dakota. Cattle finished on the low alfalfa diet were (P < or = 0.014) more tender and juicy but had more bloody notes. No (P ge; 0.670) dietary or source effects were noted for liver-like off-flavor. Subcutaneous amounts of 18:2(n-6 trans) (r = -0.17) were inversely related to the incidence of liver-like off-flavor, whereas 20:1(n-9) (r = 0.21), CLA cis-9, trans-11 (r = 0.16) were directly related. Data from this study indicate that type and level of roughage inclusion and cattle source have minimal effects on fatty acid profiles and sensory properties of the musculus rectus femoris. However, individual fatty acids of s.c. and i.m. adipose tissue were significantly correlated with liver-like off-flavor.  相似文献   

5.
Eighteen steers were used to evaluate the effect of supplemental corn oil level to steers grazing endophyte-free tall fescue on fatty acid composition of LM, stearoyl CoA desaturase (SCD) activity and expression as well as cellularity in s.c. adipose. Corn oil was supplemented (g/kg of BW) at 0 (none), 0.75 (medium), and 1.5 (high). Cottonseed hulls were used as a carrier for the corn oil and were supplemented according to pasture availability (0.7 to 1% of BW). Steers were finished on a rotationally grazed, tall fescue pasture for 116 d. Fatty acid composition of LM, s.c. adipose, and diet was determined by GLC. Total linoleic acid intake increased linearly (P < 0.01) with corn oil supplementation (90.7, 265.1, and 406.7 g in none, medium, and high, respectively). Oil supplementation linearly reduced (P < 0.05) myristic, palmitic, and linolenic acid percentage in LM and s.c. adipose. Vaccenic acid (C18:1 t11; VA) percentage was 46 and 32% greater (linear, P = 0.02; quadratic, P = 0.01) for medium and high, respectively, than none, regardless of tissue. Effect of oil supplementation on CLA cis-9, trans-11 was affected by type of adipose tissue (P < 0.01). In the LM, CLA cis-9, trans-11 isomer was 25% greater for medium than for none and intermediate for high, whereas CLA cis-9, trans-11 CLA isomer was 48 and 33% greater in s.c. adipose tissue for medium and high than for none, respectively. Corn oil linearly increased (P 0.05) the percentage of total SFA, MUFA, or PUFA but linearly increased (P = 0.03) n-6:n-3 ratio from 2.4 to 2.9 in none and high, respectively. Among tissues, total SFA and MUFA were greater in s.c. adipose than LM, whereas total PUFA, n-6, and n-3 fatty acids and the n-6:n-3 ratio were lower. Trans-10 octadecenoic acid, VA, and CLA trans-10, cis-12 were greater (P < 0.01) in s.c. adipose than in LM. Oil supplementation did not alter (P > 0.05) stearoyl CoA desaturase activity or mRNA expression. Corn oil supplementation to grazing steers reduced the percentages of highly atherogenic fatty acids (myristic and palmitic acids) and increased the percentages of antiatherogenic and anticarcinogenic fatty acids (VA and cis-9, trans-11 CLA).  相似文献   

6.
1. In a cross-over trial, the egg cholesterol and fatty acid composition of Araucana hens was compared with those of two commercial breeds (Lohmann Selected Leghorn and ISA Brown) under two feeding regimes, either high (Hn-3) or low (Ln-3) in long-chain n-3 fatty acids. 2. The Hn-3 diet was formed by isocaloric substitution of animal fat in the control diet (Ln-3) by a dry product containing stabilised fish oil with standardised concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). 3. Both breed and diet had influences on egg composition, without interactions. 4. The Araucana breed showed lower feed intake and lower egg weights than the other two breeds. The yolk weight was similar, leading to a much higher yolk:albumen ratio in the Araucana eggs. 5. In comparison to commercial breeds, Araucanas produced eggs with higher cholesterol content per g of yolk, which was even more pronounced when expressed per g of egg, due to the high yolk content of the eggs. The cholesterol content of an egg remained unchanged by the diet, irrespective of the dietary fat source. 6. Changing to the Hn-3 diet led to greater concentrations of polyunsaturated fatty acids (PUFA) and lower concentrations of monounsaturated fatty acids (MUFA) contents in the yolk, without a change in the ratio of saturated (SFA) to unsaturated fatty acids (UFA). 7. Within the PUFA, the n-3 fatty acids increased at the expense of the n-6 fatty acids, indicating a competition between n-3 and n-6 fatty acids for incorporation in the yolk.  相似文献   

7.
The objectives of this study were to determine the nutrient composition of grass-fed beef in the United States for inclusion in the USDA National Nutrient Database for Standard Reference, and to compare the fatty acid composition of grass-fed and conventionally fed (control) beef. Ground beef (GB) and strip steaks (SS) were collected on 3 separate occasions from 15 grass-fed beef producers that represented 13 different states, whereas control beef samples were collected from 3 regions (Ohio, South Dakota, and Texas) of the United States on 3 separate occasions. Concentrations of minerals, choline, vitamin B(12), and thiamine were determined for grass-fed beef samples. Grass-fed GB samples had less Mg, P, and K (P < 0.05), and more Na, Zn, and vitamin B(12) (P < 0.05) than SS samples. Fat color, marbling, and pH were assessed for grass-fed and control SS. Subjective evaluation of the SS indicated that grass-fed beef had fat that was more yellow in color than control beef. Percentages of total fat, total cholesterol, and fatty acids along with trans fatty acids and CLA were determined for grass-fed and control SS and GB. Grass-fed SS had less total fat than control SS (P = 0.001), but both grass-fed and control SS were considered lean, because their total fat content was 4.3% or less. For both GB and SS, grass-fed beef had significantly less (P = 0.001 and P = 0.023, respectively) content of MUFA and a greater content of SFA, n-3 fatty acids, CLA, and trans-vaccenic acid than did the control samples. Concentrations of PUFA, trans fatty acids, n-6 fatty acids, and cholesterol did not differ between grass-fed and control ground beef. Trans-vaccenic acid (trans-11 18:1) made up the greatest concentration of the total trans fats in grass-fed beef, whereas CLA accounted for approximately 15% of the total trans fats. Although the fatty acid composition of grass-fed and conventionally fed beef was different, conclusions on the possible effects of these differences on human health cannot be made without further investigation.  相似文献   

8.
The effect of dietary n-3 fatty acids on the fatty acid composition and lipid peroxidation of different tissues in pigs were studied. 20 castrated male pigs were included in this investigation, one half was fed daily a diet containing 1.3 g n-3 fatty acids/kg diet (control) and 10 pigs were fed a diet containing 14 g n-3 fatty acids/kg diet (n-3 diet) at the growing-finishing period. The intake of dietary n-3 fatty acids increased the concentration of these fatty acids in backfat, and the neutral and polar fractions of skeletal muscle and heart homogenates. The polar fraction showed an increased relative concentration of n-3 fatty acids in comparison to control, while the n-6 fatty acid content was reduced. In heart homogenates there was an enlargement of n-3 fatty acids both in polar lipids and in neutral lipids whilst n-6 fatty acids were decreased. Feeding n-3 fatty acid enriched diet had no influence on meat quality parameters drip loss, meat colour or pH value. The lipid peroxidation (measured as malondialdehyde equivalents) was in the order liver > heart > skeletal muscle with higher values in the n-3 group. However, by stimulation of oxidation by Fe2+/ascorbate for 3 hours the order of oxidative products in the n-3 group was muscle > liver > heart, whereas in the control group the order was liver > heart = muscle. Summarized, feeding a highly n-3 fatty acid enriched diet caused an incorporation of these fatty acids and increased the susceptibility to peroxidation in all investigated tissues.  相似文献   

9.
Our objective for this study was to determine whether there is a difference in the fatty acid composition of phospholipids in longissimus muscle from pigs of different genotypes. In Exp. 1, 15 Hampshire x Yorkshire-Landrace (YL), 15 Duroc x YL, and 15 Danbred x YL were used. Animals were of similar age and were fed identical diets. In Exp. 2, longissimus muscle samples from pigs of seven genetically different lines were analyzed. In both experiments, saturated fatty acids (SFA, 16:0 and 18:0) constituted approximately 31.5% of the total fatty acids. Monounsaturated fatty acid (MUFA, 18:1 and 20:1) levels ranged from 12.3 to 16.9%, and PUFA (mainly 18:2 and 20:4) accounted for 50.8 to 57.0% of the total fatty acids. Fatty acid composition of muscle phospholipids from Duroc and Hampshire x YL pigs was identical. Muscle phospholipids from Danbred x YL pigs contained more PUFA (approximately 3%, P < .05) and less SFA (approximately 2%, P < .05) than phospholipids from the two other genotypes. Differences in SFA and PUFA of muscle from the seven lines were of the same order of magnitude. Differences in MUFA content were not significant.  相似文献   

10.
Although dietary n-3 fatty acids have been extensively studied in poultry, they have not yet been prospectively investigated in psittacines, despite potential benefits for preventing and treating atherosclerosis, osteoarthritis, and other chronic disease processes. The objectives of this study were to investigate the incorporation of dietary n-3 fatty acids into red blood cells (RBC) and to determine the effects of supplementation of psittacine diets with fish or flax oil on plasma lipids and lipoproteins in the cockatiel. Adult cockatiels were fed a custom-formulated diet containing either 4% (wt/wt, as-fed) beef tallow (CON), 3% fish oil + 1% tallow (FSH), or 3.5% flax oil + 0.5% tallow (FLX; n = 20 per diet group). Baseline measurements were obtained for RBC fatty acid composition, triacylglycerides (TAG), and cholesterol. After 8 to 13 wk on the study diets, plasma chemistry profiles, lipoprotein density profiles, and RBC fatty acid composition were determined. At 8 wk, total plasma cholesterol was least in FSH birds (P < 0.05) and TAG concentrations were less in FSH birds than FLX birds (P < 0.05). Total n-3 fatty acids, docosahexaenoic acid, docosapentaenoic acid, and eicosapentaenoic acid were markedly greater in the RBC of FSH birds than FLX or CON birds (P < 0.05). Alpha linolenic acid was greatest in FLX (P < 0.05). Initial and final BW, and nonlipid plasma chemistry values did not differ among diet groups. No adverse effects of dietary supplementation of cockatiels with 3.5% flax oil or 3% fish oil were observed during the 13-wk feeding period. Although fish and flax oils provided similar total n-3 PUFA to the diets, fish oil caused greater reductions in cholesterol and TAG, and greater total RBC n-3 incorporation. Thus, dietary modification of psittacine diets with long chain n-3 PUFA from fish oil appears safe and may be beneficial to these long-lived companion birds.  相似文献   

11.
Dietary supplementation of stearidonic acid (SDA; 18:4n-3) has been considered a possible strategy to increase n-3 unsaturated fatty acid content in ruminant products; however, little is known about its metabolism in the rumen. In vitro batch incubations were carried out with bovine ruminal digesta to investigate the metabolism of SDA and its biohydrogenation products. Incubation mixtures (4.5 mL) that contained 0 (control), 0.25, 0.50, 0.75, 1.00, 1.25, or 1.50 mg of SDA supplemented to 33 mg (DM basis) of commercial total mixed ration based on corn silage, for dairy cows, were incubated for 72 h at 39°C. The content of most fatty acids in whole freeze-dried cultures was affected by SDA supplementation. Branched-chain fatty acids decreased linearly (P < 0.01), and odd-chain fatty acids decreased quadratically (P < 0.01), particularly from 1.00 mg of SDA and above, whereas most C18 fatty acids increased linearly or quadratically (P ≤ 0.04). Stearidonic acid concentrations at 72 h of incubation were very small (<0.6% of total fatty acids and ≤0.9% of added SDA) in all treatments. The apparent biohydrogenation of SDA was extensive, but it was not affected by SDA concentration (P > 0.05). Biohydrogenation followed a pattern similar to that of other C18 unsaturated fatty acids up to 1.00 mg of SDA. Stearic acid (18:0) and vaccenic acid (18:1 trans-11) were the major fatty acids formed, with the latter increasing 9-fold in the 1.00 mg of SDA treatment. At greater inclusion rates, 18:0 and 18:1 trans isomers decreased (P ≤ 0.03), accompanied by increases in unidentified 18:3 and 18:4 isomers (P = 0.02), suggesting that the biohydrogenation pathway was inhibited. The present results clearly indicate that SDA was metabolized extensively, with numerous 18:4 and 18:3 products formed en route to further conversion to 18:2, 18:1 isomers, and 18:0.  相似文献   

12.
This study investigated the effect of modifying the n-6:n-3 fatty acid ratio (FAR) of diets using linseed, soybean, and cottonseed oils on apparent digestibility, ruminal fermentation characteristics, growth performance, key circulating hormones, and the fatty acid profile of ruminal digesta, liver, and fore-shank muscle of growing lambs fed a high concentrate diet. Forty individually housed Katadhin Dorper lambs (average of 20.0 kg of BW) were fed Bermudagrass hay in ad libitum amounts and concentrates at 3.7% of BW daily. The concentrate contained 68.9% corn, 23.8% soybean meal, 3.3% limestone, and 4.0% oil supplements (DM basis). The treatments consisted of dietary n-6:n-3 FAR of 2.3:1, 8.8:1, 12.8:1, and 15.6:1. After feeding for 35 d in metabolism crates, lambs were slaughtered 15 h after feeding, and samples of ruminal digesta, blood, liver, and foreshank tissue were collected. Increasing dietary n-6:n-3 FAR did not affect the intake of DM nor the apparent digestibility of DM, ether extract, NDF, or ADF, but did increase apparent digestibility of CP (linear, P < 0.05). Concentrations of ruminal butyrate increased linearly (P < 0.05) with increasing dietary n-6:n-3 FAR, whereas the valerate concentration decreased linearly (P < 0.001). Concentrations of plasma insulin and IGF-I were not affected by dietary n-6:n-3 FAR. Concentrations of C18:3n-3 increased linearly (P < 0.001), whereas that of C18:2n-6 decreased linearly (P < 0.001) in ruminal digesta with decreasing dietary n-6:n-3 FAR. Concentrations of transisomers of fatty acids in ruminal digesta did not change. Proportions of C18:0 in liver and foreshank muscle were unchanged by diet. The proportion of trans11 C18:1 and cis-9 trans11 CLA decreased (P < 0.05) in liver but increased (P < 0.05) in foreshank muscle as dietary n-6:n-3 FAR decreased. Proportions of all measured n-3 fatty acids were greater in liver when diets contained more C18:3n-3 from linseed oil. By decreasing the dietary n-6:n-3 FAR, the proportions of n-6 fatty acids in foreshank muscle decreased dramatically; specifically, C18:2n-6 decreased linearly (P < 0.001) from 28.0 to 16.5% and C20:4n-6 decreased linearly (P < 0.001) from 14.7 to 8.6%. Although feeding a diet that contained more n-3 fatty acids increased the n-3 fatty acid concentration of muscle, the ratio of PUFA to SFA was decreased.  相似文献   

13.
Contents
The effect of dietary supplementation with cod liver oil (CLO), which is rich in n-3 polyunsaturated fatty acids (PUFAs), on resistance to cold shock and on freezability of boar semen was investigated. Ejaculates from 29 fertile Norwegian Landrace boars, randomly divided into control (n = 15) and CLO-group (n = 14), were frozen before and after a 12 week period of daily oil supplementation. Before each freezing, semen samples were taken to determine the fatty acid composition of the spermatozoa. Docosahexaenoic acid (22 : 6n-3; DHA) was the major fatty acid in total lipids. The n-3 fatty acid DHA increased in the CLO-group from 25.5 to 32.1% at the expense of the n-6 docosapentaenoic acid (22 : 5n-6), which decreased from 11.3 to 4.2% (p < 0.0001). The concentration of these fatty acids were unchanged in the control group. There was also a significant decrease of other PUFAs in the CLO-group (p < 0.05). Eicosapentaenoic acid (20 : 5n-3) was not found in any sample. At four different steps of the preservation process (30, 15, 5°C and after freezing/thawing) both motility and acrosome integrity were assessed. No significant differences were found either within or between the groups at any of the steps. In conclusion, CLO-supplementation alters the lipid composition of the membranes of boar spermatozoa, however, this does not seem to have any beneficial effect on cold shock and freezability of boar semen.  相似文献   

14.
本研究旨在探讨能量水平对舍饲育肥牦牛肌肉理化指标和氨基酸、脂肪酸组成及含量的影响。选取60头体况良好、平均体重为（192.66±3.64）kg的3周岁左右的舍饲育肥麦洼公牦牛,采用完全随机试验设计,每组20个重复,每个重复1头牦牛。饲喂粗蛋白质（CP）水平为14.81%,增重净能（net energy for gain,NEg）分别为4.17（低能量组,LE）、4.48（中能量组,ME）、4.79 MJ/kg（高能量组,HE）的3种日粮。试验期共97 d,其中预试期7 d,正试期90 d。结果显示,各处理组牦牛肌肉的pH、熟肉率和滴水损失3个理化指标均无显著差异（P>0.05）;各处理组牦牛肌肉常规营养成分的水分、粗蛋白质、粗脂肪、钙和磷含量无显著差异（P>0.05）;除ME组牦牛肌肉中的脯氨酸（Pro）和组氨酸（His）含量显著高于其余两组外（P<0.05）,总氨基酸和其他种类的氨基酸含量差异不显著（P>0.05）;ME组单不饱和脂肪酸、多不饱和脂肪酸及总不饱和脂肪酸相对含量显著高于LE、HE组（P<0.05）,HE组总饱和脂肪酸显著高于LE、ME组（P<0.05）。对于各种类脂肪酸,ME组的C15：1 n-3、C16：1 n-2和C18：1 n-8 3种单不饱和脂肪酸含量均显著大于其余两组（P<0.05）;而HE组的C17：0含量则有显著高于其余两组的趋势。在本试验条件下,舍饲育肥牦牛日粮中适宜的NEg水平为4.48 MJ/kg（日粮DM）,适宜日粮NEg水平能提高牦牛肌肉中脂肪酸的含量。  相似文献   

15.
This experiment was conducted to investigate the effects of energy level on the physical and chemical indicators,the composition and content of amino acids and fatty acids in muscle of house-fed yaks.A complete randomized design was adopted in this study,and sixty healthy and 3-year-old Maiwa yaks with an average body weight of (192.66±3.64)kg were randomly divided into 3 groups with 20 replicates per group and 1 yak per replicate.Diets for all groups were of the same crude protein content (14.81%) and different net energy levels for gain (NEg) with 4.17(LE),4.48(ME) and 4.79 MJ/kg (HE),respectively for 97 days (7-day pretrial period,and 90-day feeding trial).The results showed as follows:The level of energy had no effect on the value of pH,cooking yield,drip loss,moisture,crude protein (CP),crude fat (EE),calcium (Ca) and phosphorus (P) (P>0.05).Except for the content of proline and histidine in muscle of group ME were significantly higher than the other groups (P<0.05),the content of total amino acids and other kinds of amino acids had no significant difference (P>0.05).The content of monounsaturated fatty acids,polyunsaturated fatty acids and total unsaturated fatty acids in ME group were significantly higher than the LE and HE groups,and the content of total saturated fatty acids in HE group higher than the LE and ME groups.For all kinds of fatty acid,the content of C15:1 n-3,C16:1 n-2 and C18:1 n-8 three monounsaturated fatty acids in ME group significantly increased than the other two groups (P<0.05);And the content of C17:0 in HE group had a significat rise trend.In conclusion,we recommend 4.48 MJ/kg (DM basis) as a diet appropriate NEg level for the barn feeding of fattening yak under this experimental condition,appropriate NEg level of diet could improve the fatty acids content in muscle of the yaks.  相似文献   

16.
Bacterial autolysate, a down stream product of bacterial biomass grown on natural gas by mainly the methanotrophic bacteria Methylococcus capsulatus, was fed at 8% as is to broiler chickens from 1 to 35 days of age for studies of fatty acid composition, lipid oxidation and sensory quality of thigh meat stored frozen for 6 month at -18 °C or -80 °C. Lipid oxidation was measured by thiobarbituric acid reactive substances (TBARS) and volatile profile by dynamic headspace gas chromatography. Adding bacterial autolysate to diets did not affect the total content of saturated, monounsaturated or polyunsaturated fatty acids in thigh meat, but increased the levels of C14:0, C16:0, C18:0 and C16:1n-7 and reduced the levels of C18:1n-7, C18:2n-6 and C18:3n-3 fatty acids. Feeding of bacterial autolysate tended (p < 0.08) to reduce TBARS of meat samples. Contents of volatiles were generally low, but feeding of bacterial autolysate significantly reduced levels of butanal (p < 0.04) and tended to reduce levels of hexanal (p < 0.11), pentanal (p < 0.09), 1-penten-3-ol (p < 0.08) and butanone (p < 0.08). Bacterial autolysate had no effects on sensory quality parameters of meat related to odour and flavour. To conclude, adding bacterial autolysate to diets did not affect the relative proportion of saturated, monounsaturated or polyunsaturated fatty acids, but reduced content of volatiles in frozen-stored broiler meat. The reduced susceptibility to lipid oxidation in broiler meat may be related to antioxidant properties of the bacterial autolysate.  相似文献   

17.
Four different plant secondary metabolites were screened for their effect on rumen biohydrogenation of forage long-chain fatty acids, using dual-flow continuous culture fermenters. Treatments were as follows: control (no additive), positive control (12 mg/L of monensin), and plant extracts (500 and 1,000 mg/L of triterpene saponin; 250 and 500 mg/L of quercetin; 250 mg/L of eugenol; 500 mg/L of cinnamaldehyde). Monensin increased propionate, decreased acetate and butyrate proportions, and inhibited the complete biohydrogenation of fatty acids resulting in the accumulation of intermediates of the biohydrogenation process (C18:2 trans-11, cis-15 rather than C18:1 trans-11). Cinnamaldehyde decreased total VFA concentration and proportions of odd and branched-chain fatty acids in total fat effluent. Apparent biohydrogenation of C18:2n-6 and C18:3n-3 was also less, and a shift from the major known biohydrogenation pathway to a secondary pathway of C18:2n-6 was observed, as evidenced by an accumulation of C18:1 trans-10 and trans-10, cis-12 CLA. Quercetin (500 mg/L) increased total VFA concentration, but no shifts in the pathways or extent of biohydrogenation were observed. Eugenol resulted in the accumulation of C18:1 trans-15 and C18:1 cis-15, end products of an alternative biohydrogenation pathway of C18:3n-3. Triterpene saponins did not affect the fermentation pattern, the biohydrogenation pathways, or the extent of biohydrogenation. At the doses tested in this study, we could only show a direct relation between changes in the rumen fatty acid metabolism and the presence of cinnamaldehyde but not for eugenol, quercetin, or triterpene saponins.  相似文献   

18.
旨在研究代乳粉中添加枯草芽孢杆菌（Bacillus subtilis）对7~28日龄羔羊生长性能、组织器官、腹泻率及肌肉组织脂肪酸含量的影响。本研究选取体况发育良好的7日龄湖羊公羔（双羔）30只,按同质性原则将羔羊随机分为2组,每组15只,每只为1个重复,给2组羔羊分别饲喂枯草芽孢杆菌含量为0和0.2%的代乳粉,试验期为21 d。在7、14、21和28日龄晨饲前进行称重,计算各生长阶段的平均日增重（average daily gain,ADG）。并且每天饲喂羔羊的同时观察羔羊腹泻情况,计算羔羊腹泻率。在28日龄时每组随机选择8只羔羊进行屠宰,屠宰后称量各组织器官重量,计算其相对指数,并采集羔羊背最长肌和肱二头肌,测量肌内脂肪含量。结果表明：1）枯草芽孢杆菌显著降低了7~14日龄羔羊的末重（P<0.05）,显著提高了15~21日龄和22~28日龄羔羊的平均日增重（P<0.05）,有提高7~28日龄羔羊平均日增重的趋势（P=0.100）;对7~28日龄羔羊腹泻率的无显著影响（P>0.05）。2）枯草芽孢杆菌显著降低了7~28日龄羔羊胰腺重量（P<0.05）,显著增加了蹄占宰前活重比例（P<0.05）,对其他组织器官没有显著影响（P>0.05）。3）枯草芽孢杆菌对7~28日龄羔羊皮张发育无显著影响（P>0.05）。4）枯草芽孢杆菌显著降低了羔羊背最长肌不饱和脂肪酸（unsaturated fatty acid,UFA）、单不饱和脂肪酸（monounsaturated fatty acid,MUFA）、棕榈酸、硬脂酸、二十烷酸、棕榈烯酸、油酸含量和MUFA∶多不饱和脂肪酸（polyunsaturated fatty acid,PUFA）（P<0.05）,显著提高了十五烷酸、肉豆蔻烯酸、神经酸含量和饱和脂肪酸（saturated fatty acid,SFA）∶UFA （P<0.05）;显著降低了羔羊肱二头肌UFA、SFA、MUFA、棕榈酸、硬脂酸、二十烷酸、棕榈烯酸、油酸含量和MUFA∶PUFA （P<0.05）,显著提高了PUFA、n-6PUFA、肉豆蔻烯酸、神经酸含量和SFA∶UFA、PUFA∶SFA （P<0.05）。结果表明,在代乳粉中添加枯草芽孢杆菌对7~28日龄湖羊羔羊腹泻率、器官和皮张的发育无显著影响,但羔羊平均日增重和胴体重有升高趋势。枯草芽孢杆菌显著降低了湖羊羔羊背最长肌中UFA、MUFA、MUFA∶PUFA的含量和肱二头肌UFA、SFA、MUFA、MUFA∶PUFA的含量,显著提高了湖羊羔羊背最长肌中SFA：UFA的含量和肱二头肌中PUFA、n-6PUFA、SFA∶UFA、PUFA∶SFA的含量,表明枯草芽孢杆菌可通过对肌内脂肪酸组成比例和含量的影响,起到改善湖羊羔羊肉品质的作用。  相似文献   

19.
This study was designed to investigate whether transcutaneous electrical nerve stimulation (TENS) of the longissimus dorsi muscle (MLD) of rabbits induces specific proportional changes in the muscle fatty acid composition. Ten 4-week-old Pannon White rabbits were exposed to TENS treatment two times a day, with the following settings: 30 Hz, 20 micros impulse length, 10 mA, 2 x 20 min. After a treatment period of 50 days rabbits were slaughtered and the fatty acid composition of the MLD was determined by gas chromatography. The TENS treatment increased the proportions of linoleic (C18:2 n-6), linolenic (C18:3 n-3) and gondoic acids (C20:1 n-9), compared with the control group. The level of palmitic (C16:0), stearic (C18:0), oleic (C18:1 n-9) and eicosapentaenoic (C20:5 n-3) acids significantly decreased. The proportion of total unsaturated fatty acids significantly increased. On the basis of the results obtained, TENS may have similar effects on the muscle fatty acid profile like physical training. Based on the supposal that the composition of membrane structure was also affected, the electrical stimulation of muscles may have further consequences, e.g. on membrane properties.  相似文献   

20.
试验旨在分析研究乌珠穆沁草原饲养澳大利亚黑安格斯肉牛肌内脂肪酸含量和组成,为今后该品种的饲养改良、杂交繁育及肉品质的提高提供科学的基础数据.试验采集7头体重为(500±38)kg澳大利亚黑安格斯肉牛的里脊、臀肉、肩肉、眼肉、上脑、胸肉和米龙等不同部位肉样,采用简单高效脂肪酸提取方法,用气相色谱仪测定脂肪酸组成与含量,并与FAO/WHO推荐值比较,进行脂肪酸营养价值分析.结果表明黑安格斯肉牛不同部位牛肉中饱和脂肪酸(SFA)含量由多到少顺序为里脊、上脑、眼肉、肩肉、胸肉、臀肉及米龙,皆以棕榈酸和硬脂酸含量为主;单不饱和脂肪酸(MUFA)中油酸含量最高;检出的多不饱和脂肪酸(PUFA)多为亚油酸和亚麻酸;臀肉P/S和M/S最高,n-3/n-6 PUFAs比值达到0.85,接近FAO/WHO推荐值.以上结果表明乌珠穆沁草原饲养的黑安格斯肉牛的肉质风味良好,有较高的营养价值.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号