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1.
OBJECTIVE: To determine the effects of carnitine (Ca) or taurine (Ta) supplementation on prevention of lipid accumulation in the liver of cats. ANIMALS: 24 adult cats. PROCEDURE: Cats were fed a weight-gaining diet sufficient in n-6 polyunsaturated fatty acids (PUFAs), low in long-chain n-3 PUFAs (n-3 LPUFA), and containing corn gluten for 20 weeks. Cats gained at least 30% in body weight and were assigned to 4 weight-reduction diets (6 cats/diet) for 7 to 10 weeks (control diet, control plus Ca, control plus Ta, and control plus Ca and Ta). RESULTS: Hepatic lipids accumulated significantly during weight gain and weight loss but were not altered by Ca orTa after weight loss. Carnitine significantly increased n-3 and n-6 LPUFAs in hepatic triglycerides, decreased incorporation of 13C palmitate into very-low-density lipoprotein and hepatic triglycerides, and increased plasma ketone bodies. Carnitine also significantly increased weight loss but without altering the fat to lean body mass ratio. Taurine did not significantly affect any variables. Diets low in n-3 LPUFAs predisposed cats to hepatic lipidosis during weight gain, which was further exacerbated during weight loss. Mitochondrial numbers decreased during weight gain and weight loss but were not affected by treatment. Carnitine improved fatty acid oxidation and glucose utilization during weight loss without correcting hepatic lipidosis. CONCLUSIONS AND CLINICAL RELEVANCE: The primary mechanism leading to hepatic lipidosis in cats appears to be decreased fatty acid oxidation. Carnitine may improve fatty acid oxidation but will not ameliorate hepatic lipidosis in cats fed a diet low in n-3 fatty acids.  相似文献   

2.
OBJECTIVE: To determine effects of dietary lipid and protein on plasma lipoprotein and free fatty acid concentrations and hepatic fatty acid synthesis during weight gain and rapid weight loss in cats. ANIMALS: 24 ovariohysterectomized cats. PROCEDURE: Cats were fed a high energy diet until they gained 30% of their ideal body weight and then randomly assigned to receive 1 of 4 weight reduction diets (6 cats/diet) at 25% of maintenance energy requirements. Diets contained a low or high quality protein source and a lipid source deficient or sufficient in long chain essential fatty acids. Plasma samples and liver biopsy specimens were obtained before and after weight gain and during and after weight loss for determination of free fatty acid, triglyceride, and lipoprotein concentrations. Synthesis of these substances was measured by use of isotope enrichment. RESULTS: Plasma total cholesterol concentration and concentration of lipoprotein fractions increased after weight gain, compared with baseline values. Weight loss resulted in a significant decrease in concentrations of all lipoprotein fractions except high density lipoprotein. High density lipoprotein concentration was significantly greater in cats fed diets containing an oil blend, compared with cats fed diets containing corn oil. Fatty acid synthesis after weight loss was below the detection limit of the measurement technique. CONCLUSIONS AND CLINICAL RELEVANCE: In cats undergoing rapid weight loss there is neither increased triglyceride synthesis nor decreased transport of very low density lipoproteins from the liver, suggesting that their involvement in the development of hepatic lipidosis may be minimal.  相似文献   

3.
OBJECTIVE: To determine effects of dietary lipid and protein on development of hepatic lipidosis (HL) and on physical and biochemical indices following rapid weight loss in cats. ANIMALS: 24 ovariohysterectomized cats. PROCEDURE: Cats were fed a high energy diet until they gained 30% of their ideal body weight and then randomly assigned to receive 1 of 4 weight-reduction diets (6 cats/diet) at 25% of maintenance energy requirements per day. Diets contained a low or high quality protein source and a lipid source deficient or sufficient in long chain essential fatty acids (LCEFA). Serum and plasma samples and liver biopsy specimens were obtained for biochemical analyses and determination of hepatic lipid content before and after weight gain and during and after weight loss. RESULTS: Irrespective of weight-reduction diet fed, all cats lost weight at a comparable rate (4.51 to 5.00 g/d/kg of obese body weight). Three cats developed hepatic lipidosis. Significant changes in plasma insulin, cholesterol, triglyceride, and serum glucose concentrations were detected after weight gain and weight loss in all diet groups, but values for these variables did not differ among groups. CONCLUSIONS AND CLINICAL RELEVANCE: Cats can lose 25 to 30% of their obese body weight over 7 to 9 weeks without developing overt clinical signs of HL, provided that weight-reduction diets are highly palatable, contain a high quality protein, have a source of LCEFA, and are fortified with vitamins and microminerals. However, rapid weight loss may increase risk factors associated with development of diabetes mellitus.  相似文献   

4.
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   

5.
The omega-3 fatty acid (FA) enrichment of yolk is a key means one of the main objectives to improve the nutraceutical properties of eggs. We evaluated the effect of the dietary inclusion of extruded linseed fed to laying hens on the fatty acid composition of the polar and non-polar lipid classes of the eggs. Two groups of 36 Lohmann White Leghorn layers (65 weeks old) were each fed one of two different diets for a period of 12 weeks. The two diets consisted of a conventional cereal-based diet concentrate (C) and a diet concentrate containing 5% linseed (L). The inclusion of linseed in the diet increased the content of α-linolenic (C18:3n-3), eicosapentaenoic (C20:5n-3) and docosahexaenoic (C22:6n-3) acids in neutral lipids, while a concomitant decrease in arachidonic acid (C20:4n-6) was observed. As regards the polar fraction, the fatty acid composition was slightly affected by the dietary treatments except for C18:0 (+1.14 fold), C18:2n-6 (+1.23 fold), C18:3n-3 (+2.8 fold) and C22:6n-3 (+1.41 fold). Principal component analysis demonstrated that very long-chain FAs were more representative of polar lipids, except for C20:5n-3, while neutral lipids were characterized by dietary n-3 FA (C18:3n-3).  相似文献   

6.
An 18-week feeding trial was performed to investigate the effects of an omega-3 (n-3) fatty acid-enriched ration on plasma fatty acid concentrations and platelet aggregation in healthy horses. Flaxseed oil served as the source of the n-3 fatty acid alpha-linolenic acid (ALA). Twelve horses were fed dietary maintenance requirements using a complete pelleted ration (80%) and timothy grass hay (20%) for a 2-week acclimation period before being randomly assigned either to a treatment (group 1) or control (group 2) group. Group 2 horses (n = 6) were fed the diet described in the acclimation period, whereas group I horses (n = 6) were fed a 10% flaxseed oil-enriched complete pellet (80%) and grass hay (20%). Biological samples and physical measurements were collected at one point during the acclimation period (week 0) and every 4 weeks thereafter (weeks 4, 8, 12, and 16). Body weight, CBC (including platelet count), plasma fibrinogen. electrolyte (Na, K, and Cl) concentrations, and biochemical profile enzyme activities (aspartate aminotransferase, alkaline phosphatase, gamma-glutamyltransferase, and creatine kinase) did not change markedly with diet. Platelet aggregation was not altered by the supplementation of flaxseed oil in these healthy horses, although increases in plasma cis-polyunsaturated 18-carbon fatty acids C18:3; n-3 (ALA) and C18:2; n-6 (linoleic acid), biologically active C20:5; n-3 (eicosapentaenoic acid [EPA]), and malondialdehyde (MDA) were evident. There were no marked decreases in C20:4; n-6 (arachidonic acid [AA]) or increases in C22:6; n-3 (docosahexaenoic acid [DHA]), signifying that flaxseed oil may have had a high percentage of omega-6 (n-6) fatty acids as well as n-3 fatty acids, and this relatively high n-6: n-3 fatty acid ratio may have affected the biochemical effect of n-3 fatty acids. In healthy horses supplemented with flaxseed oil, platelet aggregation was not altered, which may have been due to the limited biologic effect in healthy subjects or the inability of flaxseed oil to induce the necessary biochemical effect of replacing n-6 fatty acids with n-3 types.  相似文献   

7.
Effects of defatted microalgae (DFA) on fatty acid composition of eggs and tissues of hens have not been well studied. This experiment was to determine how low concentrations of supplemental DFA in the presence or absence of flaxseed oil (FO) altered fatty acid profiles of egg yolk, liver, adipose tissue, and plasma of layers. A total of 60 Shaver Leghorn layer hens (individually caged, 20-wk old) were allotted into 6 groups (n = 10) and fed a corn/soybean meal basal diet containing 0, 3, or 5% DFA and 0 (1.5% corn oil, CO) or 1.5% FO for 6 wk. BW, ADFI, egg production rate, and egg component weights were not affected by any of the dietary treatments at various time points, but egg yolk color was changed (P < 0.05) with increasing concentrations of DFA. The concentration of n-3 fatty acids in egg yolk and plasma were elevated by FO up to 9-fold (P < 0.05) starting at wk 1 or 2, and 39 to 83% (P < 0.05) by DFA. Supplemental DFA improved (P < 0.05) n-6/n-3 fatty acid ratios in egg yolk and plasma from 13 to 23 and 7 to 13, respectively, only in hens fed diets without FO. Fatty acid profiles of liver and adipose tissue (at wk 6) displayed responses to supplemental DFA and FO similar to those of egg yolk or plasma. In conclusion, supplemental 3 or 5% DFA caused moderate enrichments of n-3 fatty acids and decreased the n6/n3 fatty acid ratios of egg yolk and tissues in hens fed diets without FO.  相似文献   

8.
OBJECTIVE: To evaluate the effect of dietary fat and energy density on body weight gain, body composition, and total energy expenditure (TEE) in neutered and sexually intact cats. ANIMALS: 12 male and 12 female cats PROCEDURE: Male cats were castrated (castrated male [CM]) or underwent no surgical procedure (sexually intact male [IM]). Female cats underwent ovariectomy (spayed female [SF]) or laparotomy and ligation of both uterine tubes without ovary removal (sexually intact female [IF]). Cats were fed either the low-fat (LF) or high-fat (HF) diet for 26 weeks, with the final allocation consisting of 8 groups: IF-LF IF-HE SF-LF, SF-HF IM-LF, IM-HF, CM-LF, and CM-HF. Mean food intake for each group was recorded daily, and body weight was monitored weekly throughout the study. Body composition and TEE were measured before surgery in week 0 and at the end of the study (week 26) by isotope dilution (double-labelled water). RESULTS: N eutered cats gained significantly more body fat and body weight (53.80+/-5.79%) than sexually intact cats (27.11+/-5.79%) during the study. Body weight gain of neutered cats fed the HF diet was greater than those fed the LF diet. Following correction for body composition, TEE was similar in all groups and no pattern towards increased food intake was evident. CONCLUSIONS AND CLINICAL RELEVANCE: Weight gain in neutered cats was decreased by feeding an LF, low energy-dense diet. To prevent weight gain in cats after neutering, a suitable LF diet should be fed in carefully controlled meals rather than ad libitum.  相似文献   

9.
OBJECTIVE: To determine effects of dietary n-3 fatty acids from Menhaden fish oil on plasma alpha-tocopherol concentrations in Beagles. ANIMALS: 32 female Beagles. PROCEDURE: For 82 days, dogs were fed diets that contained 1 of 2 ratios of n-6:n-3 fatty acids (40:1 [low n-3] and 1.4:1 [high n-3]) and 1 of 3 concentrations of all-rac-alpha-tocopheryl acetate (low, 17 mg/kg of diet; medium, 101 mg/kg; and high, 447 mg/kg) in a 2 X 3 factorial study. RESULTS: Diets high in n-3 fatty acids significantly increased total content of n-3 fatty acids in plasma (17.0 g/100 g of fatty acids), compared with low n-3 diets (2.02 g/100 g of fatty acids). Mean +/- SEM plasma concentration of cholesterol was significantly lower in dogs consuming high n-3 diets (4.59 +/- 0.48 mmol/L), compared with dogs consuming low n-3 diets (5.71 +/- 0.48 mmol/L). A significant interaction existed between the ratio for n-6 and n-3 fatty acids and amount of alpha-tocopheryl acetate in the diet (plasma alpha-tocopherol concentration expressed on a molar basis), because the plasma concentration of alpha-toco-pherol was higher in dogs consuming low n-3 diets, compared with those consuming high n-3 diets, at the 2 higher amounts of dietary alpha-tocopheryl acetate. Plasma alpha-tocopherol concentration expressed relative to total lipid content did not reveal effects of dietary n-3 fatty acids on concentration of alpha-tocopherol. CONCLUSIONS AND CLINICAL RELEVANCE: Plasma alpha-tocopherol concentration is not dependent on dietary ratio of n-6 and n-3 fatty acids when alpha-tocopherol concentration is expressed relative to the total lipid content of plasma.  相似文献   

10.
The effect of a diet containing trans fatty acids (TFA) on the fatty acid composition and fat accumulation was investigated in broiler chickens. Female broilers were fed a control or a TFA-containing diet. The difference between the diets was that a part of cis 18:1 in the control diet was replaced by the TFA. Body composition, energy balance and the fatty acid composition were examined. Over the time-period studied (15 days), the body fat content and the protein content did not differ significantly between the TFA-fed group and the control. In energy balance studies, total energy intake, energy loss in excreta, energy expenditure and energy storage did not differ between the treatments. Compared to the control diet, the TFA diet resulted in significantly higher amounts of 14:0 and 18:1n-7 and lower amounts of 18:1n-9 and 20:4n-6 in the body. In conclusion, the data suggest that feeding TFA for 15 days to female broilers had no effect on energy retention, energy expenditure and energy loss in excreta or in body composition in terms of fat and protein. Only the fatty acid composition in the body was affected by the treatment with TFA. In addition, 50% of ingested TFA was incorporated into the body fat. This may have a negative effect on the dietetic value of chicken meat.  相似文献   

11.
Seven nonlactating mature Angus cows (4 to 10 yr old) were used to examine the effects of fish meal supplementation on plasma and endometrial fatty acid composition. Cows were fed a corn silage-based diet supplemented with either fish meal, a rich source of the n-3 fatty acids, eicosapentaenoate and docosahexaenoate (n = 3; 5.1% of dietary DM), or corn gluten meal (n = 4; 8.5% of dietary DM) for approximately 64 d. Cows were given 25 mg of PGF2alpha (i.m.) on d 11 and 25 of supplementation to synchronize estrous cycles. On d 18 postestrus of the second estrous cycle, cows were slaughtered, and caruncular endometrium was dissected from uteri immediately after slaughter. Jugular blood samples were collected immediately before supplementation was initiated (d 0) and at 7-d intervals for 35 d of the study. Plasma eicosapentaenoic and docosahexaenoic acids did not differ between treatment groups on d 0 (P > 0.10); however, these fatty acids were greater in cows supplemented with fish meal over the first 35 d of supplementation compared with cows supplemented with corn gluten meal (P < 0.05). Endometrial docosahexaenoic acid did not differ (P = 0.12), whereas eicosapentaenoic acid was greater (P < 0.05) in cows supplemented with fish meal than in cows supplemented with corn gluten meal. These results indicate that dietary fish meal alters plasma and endometrial n-3 fatty acid composition in beef cows.  相似文献   

12.
Fifty Suffolk-crossbred wether lambs, with an initial live weight of 29 +/- 2.1 kg, were allocated to one of five concentrate-based diets formulated to have a similar fatty acid content (60 g/kg DM), but containing either linseed oil (high in 18:3n-3); fish oil (high in 20:5n-3 and 22:6n-3); protected linseed and soybean (PLS; high in 18:2n-6 and 18:3n-3); fish oil and marine algae (fish/algae; high in 20:5n-3 and 22:6n-3); or PLS and algae (PLS/algae; high in 18:3n-3 and 22:6n-3). Lambs were slaughtered when they reached 40 kg. Growth performance and intake were similar (P > 0.35) among treatments. By contrast, gain:feed was higher (P < 0.05) in lambs fed the fish oil compared with the linseed oil or PLS/algae diets. Total fatty acid concentration (mg/100 g) in the neutral lipid of the longissimus muscle was not affected by treatment (P > 0.87) but was least (P < 0.05) in the phospholipid fraction in lambs fed the linseed oil diet. Lambs fed either diet containing marine algae contained the highest (P < 0.05) percentage of 22:6n-3 in the phospholipid (mean of 5.2%), 2.8-fold higher than in sheep fed the fish oil diet. In lambs fed the fish/algae diet, the percentage of 20:5n-3 was highest (P < 0.05), contributing some 8.7, 0.8, and 0.5% of the total fatty acids in the muscle phospholipid, neutral lipids, and adipose tissue, respectively. The percentage of 18:3n-3 in the phospholipid fraction of the LM was highest (P < 0.05) in lambs fed the linseed oil diet (6.9%), a value double that of sheep fed the PLS diet. By contrast, lambs fed the PLS diet had twice the percentage of 18:3n-3 in the muscle neutral lipids (3.8%) than those offered the linseed oil diet, and 5.5-fold greater than lambs fed the fish/algae treatment (P < 0.05), an effect that was similar in the adipose tissue. The percentage of 18:2n-6 was highest (P < 0.05) in lambs fed the PLS diet, where it contributed 33.7, 10.1, and 11.2% in the muscle phospholipid, neutral lipids, and adipose tissue, respectively. The highest (P < 0.05) muscle PUFA-to-saturated fatty acid (P:S) ratio was obtained in lambs fed the PLS diet (0.57), followed by the PLS/algae diet (0.46), and those fed the fish oil or linseed oil diets had the lowest ratios (0.19 and 0.26, respectively). The favorable P:S ratio of lambs fed the PLS/algae diet, in conjunction with the increased levels of 20:5n-3 and 22:6n-3, enhanced the nutritional qualities of lamb to more closely resemble what is recommended for the human diet.  相似文献   

13.
本试验旨在研究饲粮中添加富含二十二碳六烯酸(DHA)海藻对奶山羊青年公羔生长性能、屠宰性能、肌肉品质以及脂肪酸组成的影响。选取16只同质性较好的6月龄[平均体重为(21.90±0.98)kg]奶山羊青年公羔,随机分为2组(每组4个重复,每个重复2只羔羊),分别饲喂基础饲粮(对照组)和在基础饲粮基础上添加3%富含DHA海藻(干物质基础)的试验饲粮(试验组)。饲喂12周后,从每组随机选择4只公羔(共8只公羔)进行屠宰试验,测定屠宰性能、肌肉品质以及肌肉与脂肪组织中脂肪酸组成。结果显示:与对照组相比,1)饲粮中添加富含DHA海藻对公羔的干物质采食量、平均日增重和饲料报酬无显著影响(P>0.05);2)饲粮中添加富含DHA海藻对公羔的屠宰性能和肌肉品质无显著影响(P<0.05);3)饲粮中添加富含DHA海藻可显著降低血清中低密度脂蛋白胆固醇含量(P<0.05),显著提高高密度脂蛋白胆固醇含量(P<0.05),但对血清总胆固醇和甘油三酯含量无显著影响(P>0.05);4)饲粮中添加富含DHA海藻可显著提高肌肉和脂肪组织中DHA和n-3多不饱和脂肪酸(PUFA)含量(P<0.05),显著降低肌肉组织中n-6∶n-3 PUFA比值(P<0.05)。由此得出,在饲粮中添加富含DHA海藻对奶山羊青年公羔的生长性能、屠宰性能和肌肉品质均无显著影响,但有改善血脂指标以及肌肉与脂肪组织脂肪酸组成的潜力。  相似文献   

14.
亚麻油对育肥猪肉品质及脂肪组织脂肪酸组成的影响   总被引：1，自引：0，他引：1  
本试验旨在研究饲料添加亚麻油(linseed oil,LO)对育肥猪胴体指标、肉质及脂肪组织脂肪酸组成的影响.选用平均体质量为63 kg左右的健康大白猪84头(其中21头阉公猪),按体质量相近、性别比例一致原则随机分为3组,每组设4个重复,每个重复7头猪(1或2头阉公猪).3个处理口粮为玉米-豆粕型日粮,分别添加0%、1.5%和3.0%LO,饲养试验时间为50 d.结果显示,与对照组相比,日粮中添加LO对猪胴体和肉晶质指标均没有显著影响(P＞0.05);日粮中添加LO显著提高皮下脂肪的α-亚麻酸(ALA)(P＜0.01)、EPA(P＜0.01)、DPA(P＜0.05)含量,以及多不饱和脂肪酸(PUFA)(P＜0.05)和n-3PUFA(P＜0.01)总含量,同时显著降低花生四烯酸(P＜0.01)和二十二碳四烯酸(P＜0.01)含量,而对n-6PUFA总含量无显著影响(P＞0.05).结果表明,猪不但可以直接沉积α-亚麻酸,而且能将其进行进一步延长和脱饱和;饲料中添加1. 5% LO可将猪皮下脂肪n-6:n-3PUFA比值降至4.1:1,接近人类健康饮食推荐水平,而日粮中添加3.0%LO则能降低皮下脂肪n-6:n-3PUFA比值至2.5:1,大大增加了猪脂肪组织的保健价值.  相似文献   

15.
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   

16.
Forty-eight Duroc-cross gilts (40 kg initial BW) were fed a control or a linseed diet containing 60 g of whole crushed linseed/kg. Both diets were supplemented with 150 mg of vitamin E/kg. Eight pigs from each dietary treatment were slaughtered at 20, 60, or 100 d after the start of the experiment. There was no effect (P > 0.05) of diet on growth, carcass characteristics, or foreloin tissue composition. Feeding the linseed diet increased (P < 0.05) the content of n-3 PUFA in plasma, muscle, and adipose tissue, but docosahexaenoic acid was not (P > 0.05) altered by diet. The proportions of n-3 PUFA were highest (P < 0.01) in pigs fed the linseed-diet for 60 d, regardless of tissue (plasma, muscle, or adipose tissue) or lipid (neutral lipids and phospholipids) class. The linseed diet produced a PUFA:saturated fatty acid ratio > or = 0.4 in all groups and tissues, which is close to the recommended value for the entire diet of humans, as well as a robust decrease in the n-6:n-3 ratio. The decrease (P < 0.01) in the percentage of oleic acid in adipose tissue of pigs fed the linseed diet for 60 d could be attributed to a 40% decrease (P < 0.001) in stearoyl-CoA-desaturase activity. Diet did not (P > 0.05) affect the activities of acetyl-CoA-carboxylase, malic enzyme, or glucose-6-phosphate-dehydrogenase in any tissues. Muscle vitamin E content was decreased (P < 0.001) 30% in pigs fed crushed linseed for 60 d, whereas lower (P < 0.001) concentrations of skatole in pork fat were observed in linseed-fed pigs at all slaughter times. Inclusion of linseed (flaxseed) in swine diets is a valid method of improving the nutritional value of pork without deleteriously affecting organoleptic characteristics, oxidation, or color stability.  相似文献   

17.
The Western diet is characterized by a high intake of SFA relative to PUFA, and the consumption of n-3 PUFA is decreased relative to n-6 PUFA. Therefore, there has been much interest in recent years in ways to manipulate the fatty acid composition of meat. The objective of this work was to determine the effects of dietary extruded linseed, an n-3 PUFA source, on growth performance, carcass composition, meat quality, and oxidative stability of pigs slaughtered at 111.0 (+/-4.8) kg of BW and 160.0 (+/-9.2) kg of BW. The association of these factors with BW at slaughter was also examined. Forty barrows, 78.1 (+/-1.75) kg of initial BW, were fed a control diet (2.5% sunflower oil) or a linseed diet containing 5% of whole extruded linseed. Both diets contained 170 mg of vitamin E and 250 mug of selenium. Eight pigs from each dietary treatment were slaughtered at 110 kg of BW and the others at 160 kg of BW. There was no dietary effect (P > 0.05) on growth, carcass characteristics, meat quality, or the activity of malic enzyme in LM and backfat. Inclusion of linseed increased (P < 0.05) n-3 PUFA content in both LM and backfat and decreased the n-6:n-3 PUFA ratio from 12 to 4.5 in LM, and from 11 to 3 in backfat. Liveweight at slaughter significantly influenced carcass characteristics, meat quality, total lipid and oxidative stability of LM, malic enzyme activity in adipose tissue, and fatty acid content of LM and backfat. This study shows that the inclusion of linseed in swine diets may improve the fatty acid profile of pork without deleteriously affecting oxidation or color stability. Thus, such a feeding practice may improve human health based on the n-6:n-3 PUFA ratio recommended for the human diet.  相似文献   

18.
The incorporation and elimination rate of dietary PUFA in pork fat was investigated in this study. Experiment 1 examined the incorporation of dietary PUFA into backfat (BF) and into the triglyceride (TG) and phospholipid (PL) fractions of the i.m. fat of the loin. Experiment 2 examined the elimination of PUFA from BF due to withdrawal of PUFA from the diet. In Exp. 1, Piétrain x Seghers Hybrid pigs (70 barrows and 70 gilts averaging 11 wk of age and 30 kg initially) were assigned to five dietary treatments in a 2 x 5 factorial arrangement during a 16-wk feeding period. Pigs received a diet containing about 2.5% tallow (T) for 8, 10, 12, 14, or 16 wk, followed by a diet containing about 15% full-fat soybeans (FFS) for 8, 6, 4, 2, or 0 wk, respectively. Additionally, BF biopsies were taken every 2 wk from eight pigs on the 8-wk FFS dietary treatment, starting from the time pigs were switched to the FFS diet. Linoleic acid [18:2(n-6)], linolenic acid [18:3(n-3)], eicosadienoic acid [20:2(n-6)], arachidonic acid [20:4(n-6)], and PUFA contents in BF increased (P < .01) with time on the FFS diet, but contents of these fatty acids were similar for pigs fed FFS for 6 or 8 wk. The PUFA content of the biopsies rose throughout the FFS treatment; the greatest increase in PUFA occurred during the first 2 wk of feeding FFS. The PUFA content of the TG and PL fractions in i.m. fat of the longissimus muscle tended to increase with time on the FFS diet. The increase was significant (P < .01) in the TG fraction for 18:3(n-3) and in the PL fraction for 20:4(n-6) and 22:6(n-3). In Exp. 2, 11-wk-old pigs (10 barrows and 10 gilts) were fed a FFS-based diet from 11 to 19 wk of age, followed by the T-diet for an additional 8 wk. During the latter period, biopsies were taken every 2 wk. The elimination of PUFA from BF was greatest during the first 2 wk after the dietary change. The PUFA reached the lowest level at the age of 25 wk. These experiments show that the PUFA: saturated fatty acid ratio of BF can be increased from .34, corresponding with a T-based diet, to .55, by feeding a FFS diet for 6 wk before slaughter.  相似文献   

19.
Thirty-six Angus x Hereford heifers (365 +/- 60 kg) were used to determine the effects of supplemental dietary lipid sources on fatty acid composition of i.m., perianal (p.a.), and s.c. lipid depots. Lipid was supplied to diets as either corn oil or a rumen-protected conjugated linoleic acid (CLA) salt for two specific treatment periods of either the final 32 or 60 d on feed. Following an initial 56-d feeding period, heifers were fed one of three dietary treatments (DM basis): 1) basal diet containing 88% concentrate and 12% grass hay (CON), 2) basal diet plus 4% corn oil (OIL), or 3) basal diet plus 2% rumen-protected CLA salt (RPCLA) containing 31% CLA. The trans-10, cis-12 CLA concentration was greatest (P < 0.05) for heifers fed RPCLA and OIL diets and least (P < 0.05) for CON, regardless of time on dietary treatment. Heifers fed supplemental RPCLA had greater (P < 0.05) total CLA content than either CON- or OIL-fed heifers. Adipose tissue concentration of trans-11 vaccenic acid (TVA) was less (P < 0.05) for CON than OIL or RPCLA, which did not differ (P > 0.05). Percentages of C18:1 trans-10 were least (P < 0.05) in i.m. lipid compared with p.a. and s.c., which did not differ (P > 0.05). Following 60 d of lipid supplementation, heifers fed OIL and RPCLA had lower (P < 0.05) concentrations of oleic acid and total monounsaturated fatty acids (MUFA) compared with CON. The ratio of cis-9, trans-11 CLA:TVA was higher (P < 0.05) for heifers fed 60 vs. 32 d, but did not differ (P > 0.05) between adipose depots. Feeding OIL increased (P < 0.05) adipose concentration of C18:2 fatty acid, whereas feeding RPCLA increased (P < 0.05) total CLA isomers by 22%. Intramuscular lipid contained the lowest (P < 0.05) percentage of cis-9, trans-11 CLA, total CLA, C18:1 cis-9, C18:1 trans-10, and TVA. Total CLA and cis-9, trans-11 CLA isomers were increased (P < 0.05) in p.a. and s.c. adipose depots, whereas i.m. adipose tissue contained increased (P < 0.05) amounts of total PUFA. Results from this study indicate that short-term lipid supplementation to feedlot cattle can increase adipose tissue CLA concentrations, but only marginally (8.3 to 17.5%). Moreover, observed decreases in oleic acid and total MUFA concentrations of adipose tissues from heifers fed rumen-protected CLA or corn oil suggest that lipid supplementation may decrease delta9 desaturase activity in adipose tissues, which in turn would lower the conversion of TVA to cis-9, trans-11 CLA isomer.  相似文献   

20.
Two experiments evaluated the ability of maternal fatty acid supplementation to alter conceptus and endometrial fatty acid composition. In Exp. 1, treatments were 1) the control, a corn-soybean meal diet; 2) flax, the control diet plus ground flax (3.75% of diet); and 3) protected fatty acids (PFA), the control plus a protected fish oil source rich in n-3 PUFA (Gromega, JBS United Inc., Sheridan, IN; 1.5% of diet). Supplements replaced equal parts of corn and soybean meal. When gilts reached 170 d of age, PG600 (PMSG and hCG, Intervet USA, Millsboro, DE) was injected to induce puberty, and dietary treatments (n = 8/treatment) were initiated. When detected in estrus, gilts were artificially inseminated. On d 40 to 43 of gestation, 7 gilts in the control treatment, 8 gilts in the PFA treatment, and 5 gilts in the flax treatment were pregnant and were slaughtered. Compared with the control treatment, the flax treatment tended to increase eicosapentaenoic acid (EPA: C20:5n-3) in fetuses (0.14 vs. 0.25 +/- 0.03 mg/g of dry tissue; P = 0.055), whereas gilts receiving PFA had more (P < 0.05) docosahexaenoic acid (DHA: C22:6n-3) in their fetuses (5.23 vs. 4.04 +/- 0.078 mg/g) compared with gilts fed the control diet. Both the flax and PFA diets increased (P < 0.05) DHA (0.60, 0.82, and 0.85 +/- 0.078 mg/g for the control, flax, and PFA diet, respectively) in the chorioallantois. In the endometrium, EPA and docosapentaenoic acid (C22:5n-3) were increased by the flax diet (P < 0.001; P < 0.05), whereas gilts receiving PFA had increased DHA (P < 0.001). The flax diet selectively increased EPA, and the PFA diet selectively increased DHA in the fetus and endometrium. In Exp. 2, gilts were fed diets containing PFA (1.5%) or a control diet beginning at approximately 170 of age (n = 13/treatment). A blood sample was collected after 30 d of treatment, and gilts were artificially inseminated when they were approximately 205 d old. Conceptus and endometrial samples were collected on d 11 to 19 of pregnancy. Plasma samples indicated that PFA increased (P < 0.005) circulating concentrations of EPA and DHA. Endometrial EPA was increased (P < 0.001) for gilts fed the PFA diet. In extraembryonic tissues, PFA more than doubled (P < 0.001) the EPA (0.13 vs. 0.32 +/- 0.013 mg/g) and DHA (0.39 vs. 0.85 +/- 0.05 mg/g). In embryonic tissue on d 19, DHA was increased (P < 0.05) by PFA (0.20 vs. 0.30 +/- 0.023 mg/g). Supplementing n-3 PUFA, beginning 30 d before breeding, affected endometrial, conceptus, and fetal fatty acid composition in early pregnancy. Dynamic day effects in fatty acid composition indicate this may be a critical period for maternal fatty acid resources to affect conceptus development and survival.  相似文献   

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