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PubMed1980

Dietary fat and exercise conditioning effect on metabolic parameters in the horse.

Four isocaloric diets containing 4, 8, 12 and 16% dietary fat (as soybean oil) were fed to four horses at four intervals according to a Latin square design. After 3 weeks of conditioning at each interval, diet effects were evaluated by trotting all horses at 3.2 m/sec for 6 hours. Pre- and posttrotting responses were measured in muscle and liver glycogen, serum long-chain fatty acids, serum electrolytes, serum enzymes, serum cholesterol, plasma glucose, packed cell volume and hemoglobin. Dietary fat was highly correlated with exercise-induced plasma glucose changes and with cholesterol concentrations. Regardless of the diet, linoleate concentration was about eight times higher than that of the other fatty acids, and it increased slightly as dietary fat levels increased. Stearate concentration also increased with increasing dietary fat but palmitic and oleic acid decreased. Increases in fat intake also resulted in slight increases in liver glycogen at the resting level. Conditioning resulted in a significant decrease in exercise-induced fluctuations of serum enzymes and electrolytes but significantly increased elevations of plasma long-chain fatty acid concentrations. Resting muscle glycogen increased by 37% during the study as a result of conditioning, but there was no effect on liver glycogen at rest or after exercise. Feeding of the four levels of dietary fat in the form of soybean oil had no adverse effects and proved a safe and efficient method of providing concentrated energy to working horses.

Animals↗
PubMed2003

Exploring the occurrence and nature of comparison of one's own perceived dietary fat intake to that of self-selected others.

Lack of awareness of personal dietary fat intake is associated with a low motivation to change to a diet lower in fat. An optimistic bias in the comparison of one's own fat intake to that of others is associated with this lack of awareness. Insight into the way people make interpersonal comparisons related to fat intake may contribute to a better understanding of dietary intake and its determinants. Such insight may provide suggestions for nutrition education interventions aimed at increasing awareness and intention to change. The present study explores interpersonal comparisons involved in evaluating personal dietary fat intake. One hundred and eighty-nine respondents participated in structured telephone interviews. The respondents reported that they use interpersonal comparison information related to fat intake to some extent and that they mostly compare themselves with close relatives and friends. Respondents who intended to change to a lower fat diet and the younger ones were more likely to compare themselves with others. Comparison targets were perceived to eat small, as well as large or average amounts of fat, which may indicate that people use positive as well as negative role models for making interpersonal comparisons in terms of dietary fat intake.

Adult↗
PubMed1989

Lack of an influence of dietary fat on murine natural killer cell activity.

The influence of the degree of saturation and the concentration of dietary fat on murine natural killer (NK) cell activity was investigated using C3H/HeN and C57BL/6N mice. Mice were fed purified diets containing either 0% fat (fat free), 5 or 20% safflower oil or 5 or 20% palm oil. Safflower oil and palm oil were used because they are comparable in carbon chain length but vary in the amount of linoleic acid [18:2(n-6)]. Cytotoxicity of splenic NK cells from mice stimulated or unstimulated by the interferon inducer poly I:C was measured against either the YAC-1 lymphoma or line 168 mammary tumor targets. The number of asialo GM1+ cells was not influenced by concentration or degree of saturation of dietary fat. Generally, dietary fat had no consistent influence on NK cell cytotoxicity of spleen cells from either the high responder C3H/HeN mice or the moderate responder C57BL/6N mice against either tumor target. The level of 18:2(n-6) in NK cell-enriched splenic lymphocytes increased with greater levels of dietary safflower oil. Nevertheless, there appeared to be no correlation between lymphocyte fatty acid composition and NK cell cytotoxic capabilities. Therefore, the concentration of dietary safflower or palm oil, and thus 18:2 (n-6), did not appear to effect the number or activity of murine NK cells.

Animals↗
PubMed1987

Effect of environmental temperature and dietary fat on growth and physiological responses of newborn calves.

Effects of cold environmental temperature and supplemental dietary fat (energy) on growth rate and physiological responses of young dairy calves fed a milk replacer diet were studied. Thirty-six Holstein bull calves were randomly assigned to one of six treatments allotted in a 2(-4 degrees C or 10 degrees C) X 3(10, 17.5, or 25% dietary fat) factorial arrangement of treatments Calves began the experiment at an average of 6 d of age and received .6 kg dry milk replacer in 4 L of water daily for 3 wk. Average daily gains (kg/d) over the 3-wk trial for calves fed 10, 17.5, and 25% fat diets were-.04, .02, and .09 at -4 degrees C and .15, .22, and .20 at 10 degrees C. Gains were significantly lower for calves housed at -4 degrees C. Rectal temperatures were lower for calves at -4 degrees C than at 10 degrees C and for calves fed 10% versus 25% fat diet. Respiratory rates and water intakes were lower for calves housed at -4 degrees C but were not affected by diet. Concentrations of plasma glucose and prolactin were lower for calves housed at -4 degrees C while concentrations of plasma free fatty acids and growth hormone were not affected by temperature. Plasma free fatty acids were increased by dietary fat, and plasma growth hormone was reduced as dietary fat increased. Calves housed at -4 degrees C had higher maintenance energy requirements (.133 Mcal metabolizable energy/kg.75) than calves housed at 10 degrees C (.101 Mcal metabolizable energy/kg.75).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2003

Effects of dietary fat type and energy restriction on adipose tissue fatty acid composition and leptin production in rats.

To investigate whether dietary fatty acid (FA) composition and energy restriction (ER) interactively influence obese (ob) gene expression, rats consumed diets containing beef tallow, safflower, or fish oil ad libitum (AL) or at 60% AL intake. Circulating leptin concentrations were higher (P < 0.0001) after AL feeding, but were not influenced by dietary fat. ER decreased (P < 0.0001) weight gain and visceral adipose weight, which were positively correlated (r = 0.40 P < 0.001, r = 0.58 P < 0.0001) with circulating leptin levels. Visceral adipose ob mRNA levels were greater in animals fed unsaturated fats, particularly safflower oil, which had the highest ob mRNA levels. Circulating leptin levels did not parallel ob mRNA levels, except for the greater abundance detected in AL adipose in comparison to ER animals. In addition, visceral FA profiles reflected dietary fat source and were influenced by an interaction of dietary fat and energy. These data demonstrate that dietary fat, particularly from a plant or marine source, and ER interactively influence ob mRNA levels; however, alterations in ob mRNA do not confer changes in circulating leptin, with the exception of ER, which is a key determinant. Thus, dietary intake is an important regulator of leptin production; however, the significance of these modest changes in diet-induced obese animals requires further study.

Adipose Tissue↗
PubMed1993

Modulation of oxidative DNA damage levels by dietary fat and calories.

Decreased dietary intake of fat and/or calories generally results in a lower incidence of mammary gland tumors in rodents. Feeding of either low-fat or calorie-restricted diets to rats also has been shown to result in decreased levels of oxidative DNA damage. Since oxidative DNA damage is suggested to have a role in carcinogenesis, this may be one mechanism by which dietary change can reduce cancer risk. The effects of calorie-restricted diets on both oxidative DNA damage levels and mammary gland tumor incidence are generally more pronounced than that of low-fat diets. There is, however, some difficulty in defining what amount of fat should be used to prepare 'low-fat' and 'high-fat' rodent diets as well as what a suitable fat intake for control diets should be in studies that examine the effects of dietary fat and/or calories on tumorigenesis. In particular, the promoting effects of dietary fat may be exerted only up to a certain level of fat, above which no further effect is observed. Another difficulty in the interpretation of the results is that there may be a time-dependent effect of high fat diets on oxidative damage, with increased damage resulting only when the diets are fed for longer periods of time. The appropriate experimental approach to model human dietary exposures therefore remains to be determined. Although the effects of caloric intake on mammary gland tumorigenesis appear to be more pronounced than that of fat intake, low-fat diets still may be useful as a preventive measure in human populations to reduce breast cancer risk for individuals who cannot safely reduce their caloric intake.

Animals↗
PubMedDate not supplied

Congruence of readiness to change, self-efficacy, and decisional balance for physical activity and dietary fat reduction.

PURPOSE: The current study examines the relations between decisional balance and self-efficacy variables on stage of change between the behaviors of avoiding dietary fat and increasing exercise. DESIGN: A cross-sectional design was used. SETTING: The current study took place in public primary care clinics from four sites across Louisiana. Clinics were associated with teaching hospitals and located in urban and rural areas. SUBJECTS: Subjects included 515 adult outpatients, 60% African-American, 81% women, and 43% married. The age ranged from 18 to 87 years old, and the mean age was 45 (SD = 14). Patients were predominantly low-income (mean household income of $490 per month) and uninsured (71%). MEASURES: Standard questionnaires were given to asses stage of change, decisional balance, and self-efficacy for exercise and dietary fat reduction. RESULTS: Although the chi 2 analysis revealed that dietary fat and exercise stage of change were significantly related, Pearson chi 2 (df = 16) = 74.30, p < .001, 35% of the sample was stage incongruent between behaviors (e.g., a significant percentage of exercise maintainers were precontemplators for reducing dietary fat). Only 27% of the sample was in the same stage for both behaviors. Correlations and multivariate analyses of variance (MANOVAs) indicated that relationships between behaviors were similar to those found previously within behaviors; however, the effect sizes were markedly attenuated. CONCLUSIONS: These results have implications for healthcare providers working with weight management. Accurate assessment of readiness for change for both exercise and dietary fat consumption is critical. For many patients, readiness for change differs dramatically between the two behaviors, and interventions may need to be tailored more precisely. Providers may need to use more active, behaviorally focused interventions for the more advanced behavior while simultaneously implementing more cognitively focused interventions for the less advanced one.

Adolescent↗
PubMed2004

Insulin resistance as a modifier of the relationship between dietary fat intake and weight gain.

OBJECTIVE: To investigate whether insulin resistance modifies the rate of weight gain associated with a high percent of energy intake from dietary fat. DESIGN: Longitudinal, observational population study. SUBJECTS: A total of 782 nondiabetic Hispanic and non-Hispanic white free-living adult residents of the San Luis Valley in Colorado. MEASUREMENTS: Subjects were seen up to three times over a 14-y period. Weight, height, fasting insulin and glucose, diet by 24 h recall, and self-reported physical activity were collected at each visit. RESULTS: Percentage of energy intake from dietary fat was positively associated with weight gain over time (P=0.0103). High intake of dietary fat was more strongly related to weight gain in women than in men, and in those with lower total energy intake levels. The relationship between weight change and relative macronutrient intake also varied by baseline insulin sensitivity (P=0.0025). Weight gain over time in individuals with relative insulin resistance at baseline, as measured by QUICKI, was the greatest among those who consumed a higher percent of energy from fat. CONCLUSION: Percentage of total intake from dietary fat predicts weight change independent of total energy intake. Nondiabetic, insulin-resistant individuals are particularly susceptible to the weight gain associated with high levels of dietary fat intake. Further investigation into the relationship between insulin resistance, diet, and weight gain is warranted.

Adult↗
PubMed1999

Different dietary fats influence serum and tissue lipids and anti-cardiolipin antibody levels in autoimmune-prone NZB/W F1 mice.

To investigate the influence of different dietary fats on lipids and anti-cardiolipin antibody levels, autoimmune NZB/W F1 mice were fed on diets containing 200 g dietary fat as palm oil, lard-soyabean oil (1:1, w/w), soyabean oil, rapeseed oil or fish oil/kg. In addition, each dietary fat group was divided into an early-feeding group with feeding from 2 months of age, and a late-feeding group with feeding from 5 months of age. Serum levels of triacylglycerol, phospholipid, cholesterol and anti-cardiolipin antibody were measured at regular intervals, and mice were killed at the age of 7 months for analysis of hepatic lipid and fatty acids. The results showed that hepatic triacylglycerol and cholesterol contents were lower in mice fed on fish oil than in those fed on palm oil. In contrast, hepatic phospholipid content was higher in mice of the fish oil group than in those of the other four dietary fat groups. Composition profiles for both hepatic and renal oleic acid (18: 1n-9), linoleic acid (18: 2n-6) and eicosapentaenoic acid (20: 5n-3) were similar to those of the dietary fats in mice of both early-feeding and late-feeding groups. Fish oil intake decreased arachidonic acid (20: 4n-6) concentration in kidney tissue but not in liver tissue. Serum triacylglycerol, cholesterol and phospholipid levels were lower in mice fed on fish oil than in those fed on palm oil. Immunoglobulin (Ig) M anti-cardiolipin antibody was lower for the fish oil group than for the other groups. The IgG anti-cardiolipin antibody level was significantly lower in mice fed on fish oil compared with that of the palm oil group only in the early-feeding group. There was a positive correlation between serum IgM anti-cardiolipin antibody and phospholipid levels (early-feeding group r 0.902, P < 0.05; late-feeding group r 0.894, P < 0.05). These findings suggest dietary fish oil may affect both lipid levels and anti-cardiolipin antibody, contributing to alleviation of the autoimmune process in autoimmune-prone NZB x NZW F1 mice.

Analysis of Variance↗
PubMed1994

Influence of dietary fat and feeding period on phosphoinositide metabolism in rat colonocytes.

The objective of the present study was to examine the effect of dietary fat content on phosphoinositide (PI) metabolism, fatty acid composition in colonocytes, and colonic luminal content of bile acids (BA) and free fatty acids (FFA) in rats. Male Sprague-Dawley rats weighing approximately 166 g were fed to semipurified diet containing 3% or 21.5% beef fat and 2% corn oil. The nonfat ingredients were adjusted to correct for differences in food consumption of these diets. Animals were fed these diets ad libitum for one or four weeks. The isolated colonocytes had a viability of 88.9% in all groups. PI metabolism was examined in the absence (basal) or presence of agonists, 2 mM deoxycholic acid or 10 microM A23187. Dietary fat concentration had no effect on PI metabolism, but the length of feeding had a significant effect on basal and stimulated PI metabolism. Colonocytes of animals fed the diets for four weeks were less sensitive to stimulation of PI cycle by agonists than those of animals fed for one week. Colonocyte fatty acid composition was influenced by dietary fat and feeding period. Only the relative percentage of 20:3(n-6) was significantly lower in rats fed the high-fat diet for one week; 18:0 was lower and 18:3(n-6) was higher in colonocytes of animals fed the diets for one week than in those fed for four weeks. Several colonic fatty acids, namely, 16:0, 20:3(n-6), and 22:5(n-6), also exhibited diet-by-feeding period interaction. Intracolonic luminal contents from rats fed the high-fat diet contained elevated concentrations of BA and FFA (44% and 62%, respectively). It was concluded that despite the effects of dietary fat concentration on increased colonic BA and FFA and on altered membrane fatty acid composition, dietary fat had no effect on PI metabolism in colonocytes under the conditions in the present experiment. A difference in components between the purified diet and the commercial rat chow and/or an aging effect of the rats may alter the PI cycle of colonocytes.

Animals↗
PubMed2000

The effects of varying dietary fat on the nutrient intake in male and female runners.

OBJECTIVE: The present study examined the effects of varying dietary fat levels on nutrients in female and male endurance runners. METHODS: Three diets (low, medium and high fat) were designed for each subject using their food preferences and three-day food records. Each diet was eaten for 28 to 31 days. The diets were self-selected from seven-day sample menus. Twelve male and 13 female runners between 18 and 55 years of age who averaged 42 miles/week participated in the study. Daily food intakes, activity records and weekly palatability/hunger scales were completed. RESULTS: Dietary fat intakes, as a percent of total energy intake (%E), averaged 17%E, 31%E, and 44%E on the low, medium and high fat diets, respectively. Energy consumption was less than their estimated energy expenditure (EEE) on all diets. On the low fat diet, the female runners were consuming approximately 60% of their EEE. As dietary fat increased, the difference between calorie intake and estimated energy expenditure became less and the subjects were less hungry on the two higher fat diets. For all subjects, as energy intakes increased, so did carbohydrate intake. Therefore, carbohydrate intake was not different on the two lower fat diets. Irrespective of gender, calcium and zinc intakes, which were below 1989 RDAs, increased with increasing fat intakes, between the low and medium fat diets. Zinc intake was also higher on the highest fat diet. Essential fatty acid intakes for females on the low fat diet were less than 2.5%E. Half of the female runners ate less than the RDA of calcium and zinc on the low fat diet and Fe on the medium fat diet. CONCLUSION: This study suggests that endurance runners may not be consuming enough calories on a low fat diet and that increasing dietary fat increased energy consumption. On the low fat diet, essential fatty acids and some minerals (especially zinc) may be too low. A low fat diet could compromise health and performance.

Adult↗
PubMed1991

The effect of various dietary fats on skin tumor initiation.

The type of dietary fat has been shown to modulate the initiation stage of mammary tumorigenesis, with saturated fat fed before and/or during carcinogen treatment resulting in increased tumor incidence. This study was designed to determine whether different types of dietary fat alter the initiation stage of skin carcinogenesis by use of the initiation-promotion mouse skin carcinogenesis model. Sencar mice were divided into three groups and maintained on one of the experimental diets. The AIN-76-based diets consisted of 10% total fat with various types of fat: 8.5% menhaden oil plus 1.5% corn oil, 8.5% coconut oil plus 1.5% corn oil, and 10% corn oil. After three weeks mice were initiated with 10 nmol dimethylbenz[a]anthracene (DMBA). Two weeks later, all mice were switched to a diet containing 5% corn oil. Promotion began four weeks after initiation with twice-weekly application of 1 microgram 12-O-tetradecanoylphorbol-13-acetate and continued for 12 weeks. No statistically significant differences in kilocalories of food consumed or body weights were observed between diet groups during the study. The final papilloma incidence, yield, and size were not significantly different among the diet groups. In a parallel study, [3H]DMBA binding to epidermal DNA showed no dietary differences. Unlike the mammary carcinogenesis model, these data suggest that the type of fat fed during DMBA initiation had minimal effects on this stage of skin carcinogenesis.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1991

Physiological response of mature rats to replacement of dietary fat with a fat substitute.

The effects of replacing dietary fat with a fat substitute on food intake, body composition and lipid metabolism were examined in rats. Female Sprague-Dawley rats (250 g) were fed diets containing between 2 and 63% of energy as fat for 64 d. Inclusion of a substitute resulted in diets of different fat content but similar texture. When 10% corn oil (21% kJ-fat diet) was replaced with the substitute supplemented with linoleic acid (2% kJ-fat diet), rats increased food intake so that there was no effect on energy intake, body weight, body composition or serum lipid profile. Rats fed a diet containing 10% corn oil and 30% Crisco vegetable shortening (63% kJ-fat diet) became obese and hyperinsulinemic. When half (51% kJ-fat diet) or all (30% kJ-fat diet) of the Crisco was replaced with the fat substitute, the rats increased food intake and were fatter than controls but less obese than rats fed the 63% kJ-fat diet. Hepatic lipid oxidation and ketone synthesis were proportional to the percentage of dietary energy as fat. Adipocyte de novo lipid synthesis was inhibited by 51% kJ-fat and 63% kJ-fat diets. Partial or total replacement of Crisco prevented the hyperinsulinemia observed in 63% kJ-fat rats, suggesting a protective effect against the development of insulin resistance with diet-induced obesity.

Animals↗
PubMed1990

Influence of dietary fat on fecal mutagenicity in premenopausal women.

A dietary intervention study was conducted on 31 premenopausal women (age: 20-40 years) to investigate the relationship between dietary fat and fecal mutagenicity. After a free-living period (baseline) of one menstrual cycle, the subjects were placed on a high-fat diet (40% calories from fat) for 4 menstrual cycles, followed by a low-fat diet (20% calories from fat) for 4 menstrual cycles. One-half of the subjects were randomly assigned throughout the study to a diet with a P:S ratio of 1.0 while the other half was assigned to one with a P:S ratio of 0.3; body weight by group remained constant. Three-day stool samples were collected at the mid-follicular period during the free-living phase and during the 4th menstrual cycle of each of the 2 controlled diet periods. Mutagenicity was assayed by the SOS chromotest. Reduction of dietary fat was accompanied by a significant decrease in fecal mutagenicity in both P:S groups. Combined values, i.e., both P:S groups, were 20.3 units for high-fat diets vs. 8.78 for low-fat diets.

Adult↗
PubMed1992

Rat colonic antioxidant status: interaction of dietary fats with 1,2-dimethylhydrazine challenge.

The polyunsaturated fatty acid composition of dietary fat has been associated with increased oxidant stress in tissues. We previously showed that antioxidant mechanisms in colon mucosa are affected by dietary fat. In this study, the colonic antioxidant response to treatment with the colon-specific carcinogen 1,2-dimethylhydrazine (DMH) was determined. Sprague-Dawley rats were fed one of four AIN-76A-based diets with varied fat content. The basal diet contained 5% corn oil, the menhaden oil diet contained 19% menhaden oil and 1% corn oil, the corn oil diet contained 20% corn oil and the beef tallow diet contained 19% beef tallow and 1% corn oil. Animals were given one or two intraperitoneal injections of either DMH (20 mg/kg) or 1 mmol/L EDTA. Homogenates of colon mucosa were assayed to determine activity of catalase, glutathione peroxidase, total superoxide dismutase, manganese superoxide dismutase, glutathione reductase and glutathione-S-transferase, as well as total glutathione concentration, thiobarbituric acid-reacting substances and nuclear aberrations. Total glutathione concentration was greater in rats fed all diets following two injections of DMH, whereas glutathione reductase activity remained unchanged relative to controls. Lipid peroxidation was highest in the group fed menhaden oil; nuclear aberrations were greatest in the corn oil-fed group. In conclusion, both type and amount of dietary fat modified the response of colon tissue to genotoxic challenge, but none of the diets seemed more protective than the others.

1,2-Dimethylhydrazine↗
PubMed2000

Postprandial lipemia after short-term variation in dietary fat and carbohydrate.

Replacement of dietary fat with carbohydrate may not reduce the overall risk of coronary heart disease (CHD), because this elevates plasma triacylglycerol (TAG) concentrations. The lipoproteinemic effects of a high-carbohydrate diet are likely to be more marked shortly after the initiation of such a diet than after longer periods of intervention during which adaptive processes may counteract the initial effects. Therefore, we studied the postprandial responses to a standard meal after 3-day dietary intervention periods. An additional objective was to establish a model for future study of the mechanisms involved. Nine normolipidemic men consumed the meal (1.2 g fat, 1.1 g carbohydrate, and 0.2 g protein per 1 kg body mass) after 3 days on a high-carbohydrate diet (68% +/- 3% energy from carbohydrate, mean +/- SD) and also after 3 days on an isoenergetic high-fat diet (66% +/- 5% energy). Venous blood samples were obtained from fasted subjects and for 6 hours after the meal. In the fasted state, TAG was higher after the high-carbohydrate diet (1.18 +/- 0.18 v0.62 +/- 0.09 mmol/L, mean +/- SEM, P = .02) and high-density lipoprotein (HDL) cholesterol was lower (1.01 +/- 0.08 v 1.10 +/- 0.09 mmol/L, P = .002). The area under the plasma TAG concentration versus time curve was 42% +/- 7% higher after the high-carbohydrate diet (P = .003). After the high-carbohydrate diet, the postprandial insulin response did not differ between trials, but glucose and 3-hydroxybutyrate responses were lower (P = .009 and P = .02, respectively) and the lactate response was higher (P = .001). Plasma nonesterified fatty acids (NEFAs) were lower after the high-carbohydrate diet in the fasted state and for 4 hours postprandially, but were higher thereafter (interaction of time x trial, P = .001). These results indicate that compared with a high-fat diet, the plasma TAG response to a standard high-fat meal is markedly higher after a few days on a high-carbohydrate diet, with major differences in the associated metabolic milieu. The magnitude of these changes and the rapidity with which they developed suggest that this model may be attractive for future studies of the underlying mechanisms.

3-Hydroxybutyric Acid↗
PubMed1992

Lung eicosanoid synthesis is affected by age, dietary fat and vitamin E.

The effect of age, dietary fat type and all-rac-alpha-tocopheryl acetate (vitamin E) supplementation on ex vivo synthesis of lung eicosanoids was measured in C57BL/6NIA mice using a 2 (age) x 3 (fat) x 3 (vitamin E) factorial design. Young (3-mo-old) and old (24-mo-old) mice were fed a semipurified diet containing 5% (by wt) corn oil, coconut oil or fish oil supplemented with 30, 100 or 500 mg vitamin E/kg for 4 wk. Ex vivo synthesis of thromboxane B2 (TXB2) and 6-keto-prostaglandin F1 alpha (PGI2) were measured by RIA in lung homogenates. Old mice had significantly higher concentrations of TXB2 and PGI2 than did young mice, resulting in a significant increase in the TXB2:PGI2 ratio with aging. Young and old mice fed fish oil had significantly lower concentrations of PGI2 and TXB2 than those fed corn oil or coconut oil. The degree of reduction varied according to age and vitamin E status. Old mice fed fish oil and 30 mg vitamin E/kg diet had the lowest plasma vitamin E concentration and the highest TXB2:PGI2 ratio. The TXB2:PGI2 ratio was significantly reduced in old mice fed coconut oil or fish oil by vitamin E supplementation. Vitamin E supplementation (100 mg/kg) significantly increased PGI2 concentration in young mice fed coconut oil. Thus, significant changes in the capacity of lung to synthesize eicosanoids occur with age and are influenced by dietary fat type and vitamin E. J. Nutr.

Aging↗
PubMed1992

Composition and flavor of milk and butter from cows fed unsaturated dietary fat and receiving bovine somatotropin.

Composition and flavor of milk and butter were evaluated from cows divided into four treatments including a control, control with bST, added dietary fat from sunflower seeds with bST, or added dietary fat from safflower seeds with bST. Feeding added unsaturated dietary fat resulted in lower concentrations of short-and medium-chain and higher concentrations of long-chain fatty acids in milk fat and butter. Milk fat unsaturated fatty acid concentrations were 25.0, 28.4, 39.6, and 37.9%, and butter unsaturated fatty acid concentrations were 23.0, 26.9, 37.8, and 36.2% for control, control with bST, sunflower seeds with bST, and safflower seeds with bST, respectively. Sensory evaluations indicated that butters from the bST with sunflower seed and bST with safflower seed treatments were equal or superior in flavor to the control butter. Milk from cows receiving bST or fed added unsaturated dietary fat and receiving bST was no more susceptible to oxidized off-flavors than control milk. Butters from sunflower seed and safflower seed treatments with bST contained higher concentrations of unsaturated fatty acids, were softer at 4 and 20 degrees C, and possessed acceptable flavor and processing characteristics compared with butters from control and control with bST.

Animals↗