Biomedical subjects

M Kirchgessner

Publications and source records attributed to M Kirchgessner.

At least 73 records · Page 4Linked to original sources

PubMed1995

[B-vitamins (thiamine, vitamin b6, pantothenic acid) in lean muscle tissue of growing cattle of the German Simmental breed under different feeding intensities].

In a comparative slaughter experiment the thiamin, vitamin B6 and pantothenic acid content of lean tissue of foreloin of growing cattle was determined by whole body analyses. 54 bulls, 45 heifers and 45 steers were fed until a live mass of 200 kg, 350 kg, 425 kg (only heifers) 500 kg and 575 kg, 650 kg, respectively (only bulls and steers). One half of each carcass was divided into 13 cuts and afterwards the cuts were each divided into lean, adipose and bone tissue and tendons. The lean tissue of the foreloin was subjected to analysis of thiamin, vitamin B6 and pantothenic acid. The mean thiamin content of 0.75 mg kg-1 fresh matter (200 kg live mass) decreased with rising live mass and under intensive feeding conditions in bulls and steers to 0.53 mg and in heifers to 0.61 mg. Restrictively feeding caused a mean thiamin content of 0.60 mg per kg fresh matter in bulls, steers and heifers. Under both feeding conditions in the lean tissue of the foreloin on average a vitamin B6 content of 2.6 mg (bulls), 3.1 mg (heifers) and 3.0 mg kg-1 fresh matter (steers) was analysed. A mean content of pantothenic acid of 2.6 mg kg-1 fresh matter was determined in bulls independent of live mass and feeding intensity. In heifers the content of pantothenic acid on average was 3.0 mg under intensive feeding system and 2.6 mg under low feeding conditions, whereas steers reached contents of 2.7 mg (high feeding) and 2.2 mg kg-1 fresh matter (low feeding).

Animal Feed↗

PubMed1995

[Thermogenesis in overfeeding with administration of olive oil and fish oil in a swine model study].

A trial on total metabolism was conducted in eight nonpregnant, nonlactating sows over eight periods, each of 16 days duration, to measure potential fatty acid induced thermogenesis. During the first and last experimental periods, the animals received a basal ration which just covered the energy maintenance requirement. In the second to seventh periods supplements of olive oil, fish oil, or puffed wheat starch as reference nutrient were added to the diet in random sequence at two levels up to 50% above the maintenance requirement. All rations were calculated with reference to the sows' initial weight and remained quantitatively unchanged throughout the experiment. The animals were fed twice daily. During each metabolism period a complete energy balance was assessed for all sows by means of collection technique (feed, feces, urine), and 48-h measurements of the gas exchange in a respiration chamber. The sows' body mass increased linearly during the course of the experiment by 5.8 kg per period. The three supplement types had no influence on the animals' final body weight, wich averaged 205.5 kg with the starch supplement, 204.8 kg with olive oil, and 205.8 kg with fish oil. Energy digestibility (DE/GE) was 100% for all three supplements, and metabolizability of energy (ME/GE) one percentage point less. Carbon and energy depositions showed a pronounced linear relationship to the level of supplementation and were also influenced by the type of supplement. Heat production was 20.9 MJ/d after feeding the basal ration alone and, taking the average of the two supplementation levels, 21.6 MJ for the starch supplement, 21.0 MJ for olive oil, and 20.6 MJ for fish oil.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗

PubMed1995

[Effect on metabolism of thyroid hormones in deficient to subtoxic selenium supply levels].

In an experiment with 72 male weanling Sprague Dawley rats the effect of varying selenium intake on parameters of thyroid hormone metabolism was investigated. The animals were divided into 6 groups. One of the groups was fed a semi-synthetic diet based on casein which was poor in selenium (38 micrograms/kg). The other groups were fed the same diet supplemented with Na2SO3.5H2O to achieve a selenium concentration of 50, 100, 300, 600 and 3,000 micrograms/kg. The experiment lasted 40 days. Different selenium intake had no effect on food intake, weight gain, hematological and selected clinical-chemical parameters. Determination of glutathione peroxidase activity and selenium concentration of serum showed a selenium deficiency in animals fed the diet not supplemented with selenium. Serum T3 concentration and hepatic type-I-deiodinase activity were decreased in the group without selenium supplementation in contrast to the groups fed diets adequate in selenium (100, 300 micrograms/kg). A diet supplementation of 50 micrograms/kg already increased hepatic type-I-deiodinase activity to levels of the groups fed diets adequate in selenium. In groups supplemented with 600 and 3,000 micrograms/kg diet, serum T3 concentration was reduced by half of groups fed diets adequate in selenium. Supplementation with 3,000 micrograms Se/kg lowered the type-I-deiodinase activity in contrast to groups fed diets adequate in selenium, but not significantly. Serum concentrations of T4 and fT4 were not changed by various selenium intake. The results of this investigation show an alteration in thyroid hormone metabolism at low selenium intake as well as at high selenium intake.

Animals↗

PubMed1995

[Thermogenesis and energy utilization of olive oil and fish oil in a model study with sows].

An animal model experiment was conducted with nine adult sows to study the effect of olive oil and fish oil (40% polyunsaturated fatty acids) on thermogenesis compared to wheat starch as control. The treatments were given to each animal according to a latin square design. The basal diet (20 g DM/kg W0.75) was mainly based on barley and soybean meal, and matched 60% of the ME requirements with all the other nutrients meeting maintenance requirements. The isoenergetic supplements amounted to 176 kJ gross energy per kg W0.75 and day. During each experimental period a complete energy balance was recorded for each animal using indirect calorimetry technique (RQ-method) as well as the carbon-nitrogen-balance technique. The treatments did not influence the digestibility of the rations. Digestibility of energy and of carbon averaged 83.4% and 83.3%, respectively. All three supplements were nearly completely digested as calculated by the difference method. Fish oil increased urine energy and decreased CH4 production, the shifts, however, were in absolute terms very small. The mean O2 consumption was 1,002 l/d showing no significant treatment effects. CO2 production was lowered with olive oil by 10%, and with fish oil by 13% compared to the starch diet. The daily heat production was 20.95, 20.72, and 20.04 MJ when starch, olive oil or fish oil was given. Corrected for equal energy retention the difference of thermogenesis between olive oil and starch was -0.4 MJ/d, and between fish oil and starch -1.2 MJ/d. These differences corresponded to a relation of starch:olive oil:fish oil = 1:0.95:0.86. The relation between starch and olive oil reflected exactly the theoretical expectation, calculated from the ATP regeneration by oxidation of both nutrients. When fish oil was added, the daily heat production was lower than theoretically calculated, which might be interpreted as an effect on the metabolic rate in general rather than especially on the efficiency of ATP formation from fish oil oxidation. In any case, there was no hint of a facultative thermogenesis induced by the oils.

Adenosine Triphosphate↗

PubMed1995

Zinc deficiency and activities of lipogenic and glycolytic enzymes in liver of rats fed coconut oil or linseed oil.

In previous studies, zinc-deficient rats force-fed a diet with coconut oil as the major dietary fat developed a fatty liver, whereas zinc-deficient rats force-fed a diet with linseed oil did not. The present study was conducted to elucidate the reason for this phenomenon. In a bifactorial experiment, rats were fed zinc-adequate or zinc-deficient diets containing either a mixture of coconut oil (70 g/kg) and safflower oil (10 g/kg) ("coconut oil diet") or linseed oil (80 g/kg) ("linseed oil diet") as a source of dietary fat, and activities of lipogenic and glycolytic enzymes in liver were determined. In order to ensure adequate food intake, all the rats were force-fed. Zinc-deficient rats on the coconut oil diet developed a fatty liver, characterized by elevated levels of triglycerides with saturated and monounsaturated fatty acids. These rats also had markedly elevated activities of the lipogenic enzymes acetyl-CoA carboxylase, fatty acid synthase (FAS), glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH), and citrate cleavage enzyme, whereas activities of malic enzyme and glycolytic enzymes were not different compared with zinc-adequate rats on the coconut oil diet. In contrast, rats receiving the linseed oil diet had similar triglyceride concentrations regardless of zinc status, and activities of lipogenic enzymes and glycolytic enzymes were not different between the two groups. Zinc-deficient rats fed either type of dietary fat exhibited statistically significant correlations between activities of FAS, G6PDH, 6PGDH and concentrations of saturated and monounsaturated fatty acids in liver.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1995

Influence of dietary amiloride supplement on the zinc status of growing rats with marginal zinc supply.

We divided 36 male pathogen-free Sprague-Dawley rats with an average live mass (LM) of 51 g into four treatment groups of nine animals each. They received for a period of 28 trial days a semisynthetic purified diet based on casein for ad libitum consumption, supplemented with 5 ppm zinc (groups 1-3) or 57 ppm zinc (group 4) as zinc sulfate. In addition to the diet, groups 2 and 3 were given a diuretic supplement of amiloride at the therapeutic dose rate (0.4 mg amiloride/kg LM0.75 per day) or in a dosage corresponding to the chronic toxicity level (maximum tolerated dose; 0.8 mg amiloride/kg LM0.75 per day). The supplementation with amiloride, acting as a potential Zn-binding ligand at the selected dosage levels, had no influence on the animals' live weight during the 28-day trial period; weight gain was determined solely by the dietary Zn concentration. Amiloride administered at the therapeutic or the maximum tolerated dose produced no evidence of a diminished Zn status in terms of the alkaline phosphatase activity in the serum or the Zn concentration in the serum, femur and testes. Medication with amiloride at the maximum tolerated dose even exerted a positive effect on the zinc supply status as demonstrated by the raised Zn concentration in the serum. This suggests that zinc supplementation may not be required during medication with amiloride in human medicine.

Alkaline Phosphatase↗

PubMed1995

Activities of liver microsomal fatty acid desaturases in zinc-deficient rats force-fed diets with a coconut oil/safflower oil mixture of linseed oil.

The present study was conducted to investigate the effect of zinc deficiency on fatty acid desaturation in rats fed two different types of dietary fat, a mixture of coconut oil and safflower oil (7:1, w/w, "coconut oil diet") or linseed oil ("linseed oil diet"). In order to ensure an adequate food intake, all rats were force-fed by gastric tube. Zinc deficiency caused statistical significant reduction of delta 9-desaturase activity in liver microsomes of rats fed coconut oil diet and tendencial reduction (p < 0.15) in rats fed linseed oil diet compared with control rats fed diets with the same type of fat. In agreement with this effect, zinc deficiency in the rats fed both types of dietary fat increased the ratio between total saturated and total monounsaturated fatty in liver phospholipids and liver microsomes. Zinc deficient rats on the coconut oil diet had unchanged delta 6-desaturase activity with linoleic acid as substrate and lowered activity with alpha-linolenic acid as substrate. In contrast, zinc deficient rats on the linseed oil diet had increased delta 6-desaturase activity with linoleic acid as substrate and unchanged activity with alpha-linolenic acid. Because linoleic acid is the main substrate for delta 6-desaturase in the rats fed coconut oil diet, and alpha-linolenic acid is the main substrate in the rats fed linseed oil diet, it is concluded that in vivo delta 6-desaturation was not changed by zinc deficiency in the rats fed both types of dietary fat. Activity of delta 5-desaturase was also not changed by zinc deficiency in the rats fed both dietary fats. Levels of fatty acids in liver phospholipids and microsomes derived by delta 4-, delta 5-, and delta 6-desaturation were not consistently changed by zinc deficiency in the rats fed both types of dietary fat. Thus, the enzyme studies and also fatty acid composition data of liver phospholipids and microsomes indicate that zinc deficiency does not considerably disturb desaturation of linoleic and alpha-linolenic acid. Therefore, it is suggested that similarities between deficiencies of zinc and essential fatty acids described in literature are not due to disturbed desaturation of linoleic acid in zinc deficiency. The present study also indicates that zinc deficiency enhances incorporation of eicosapentaenoic acid into phosphatidylcholine of rats fed diets with large amounts of n-3 polyunsaturated fatty acids.

Alkaline Phosphatase↗

PubMed1995

[Marginal copper and iron supply in pigs. 2. Effect on fatty acid composition in various tissues].

The objective of the present study was to investigate the effect of a deficient copper and iron supply on the fatty acid composition of various tissues in pigs. An experiment was conducted with 4 x 12 growing pigs of the crossbreed Pietrain x Deutsche Landrasse. The animals were fed for a period of 119 days with a diet poor of copper (1.5 mg Cu/kg diet) and/or poor of iron (35 mg Fe/kg diet). Control animals were supplied adequately with copper (4.8 mg Cu/kg diet) and iron (85 mg Fe/kg diet). The diet was given according to weight. The copper and iron supply can be characterized as marginal due to a former report of this study. The total lipid and cholesterol content in serum, erythrocytes, liver and backfat was not influenced due to marginal copper and iron supply. Only in muscle there was a slightly reduction in these parameters. Marginal copper supply had no striking effect on the fatty acid composition in all examined tissues. After marginal iron supply there were some changes in the fatty acid composition in serum, erythrocytes and muscle. Saturated fatty acids raised due to declined monoenoic fatty acids, which is concluded as a reduced delta-9 desaturation.

Adipose Tissue↗

PubMed1995

[Effect of avilamycin and tylosin on the metabolizable energy in growing and finishing pigs].

In two metabolism trials with growing and finishing pigs the influence of the antibiotic feed additives Avilamycin and Tylosin on the metabolizable energy was investigated at different levels of dietary protein content. In the first experiment (growing pigs) the antibiotics were supplied at levels of 0 mg/kg, 40 mg/kg Avilamycin and 40 mg/kg Tylosin to diets containing 18.5%, 17.5%, 16.5% and 14.0% of crude protein. In the second experiment (finishing pigs) 0 mg/kg antibiotics, 20 mg/kg Avilamycin and 20 mg/kg Tylosin were used in diets containing 16.5% and 14.0% of crude protein. The body weight of the animals averaged 46 kg (growing pigs) and 68 kg (finishing pigs). In growing pigs the supplementation of Tylosin increased the digestibility of dry matter and energy at 1 percentage unit each, while in finishing pigs no effects were observed. Since the urinary energy excretion was not affected by antibiotics, there was only in Tylosin treated growing pigs a slight rise in dietary contents of metabolizable energy by 1.6%. The reduction of the dietary protein content resulted in increased digestibility of dry matter and energy, reduced urinary energy excretions and increased dietary contents of metabolizable energy.

Aging↗

PubMed1995

Response of renal orotic acid and creatinine to treatments affecting metabolic protein supply of ruminants.

90 urine samples obtained in three lamb trials and one experiment using adult wethers were analyzed for their contents of orotic acid and creatinine. The average daily excretion of orotic acid accounted for 0.5 mg to 1.5 mg (35 micrograms to 130 micrograms/W0.75) with a high individual variation. Correlation coefficients between orotic acid and other urinary constituents were low indicating an entirely different response to metabolic variations. There was only a weak relationship to live weight, protein retention and rumen fluid traits. Defaunation reduced the orotic acid excretion (significant in the adult wethers) whereas the addition of rumen-protected lysine as well as the use of different dietary carbohydrate sources were without effect. The urinary excretion of creatinine increased with live weight and age from 0.4 g/d in the 20 kg lambs to 1.7 g/d in the adult 53 kg wethers. The correlations with live weight were close whereas the apparently negative correlation with protein retention was not real as could be evaluated by calculation of the partial correlations. There was a close correlation of creatinine with total N, urea and allantoin. Neither defaunation nor rumen-protected lysine and the kind of carbohydrate source had significant effects on creatinine. The use of orotic acid and creatinine as indicators of metabolic disorders were discussed. Easy application in practical diagnosis without quantitative urine collection might be possible by the determination of orotic acid in the milk of cows and of the creatinine/N ratio in urine.

Allantoin↗

PubMed1995

[Contents and deposition of major minerals in tissues and in the whole bodies of growing young bulls German Simmental breed].

54 bulls of the German Simmental breed were fed either on a high energy level (maize silage ad libitum and 1.8 kg concentrate) or on a low energy level (maize silage restrictively and 1.0 kg concentrate). In dependence on feeding intensity a mean daily weight gain of 870 or 1210 g was obtained. Animals were slaughtered with a live mass of 200 kg, 350 kg, 500 kg, 575 kg and 650 kg. Empty body was divided into 13 cuts and afterwards separated into lean, bone and adipose tissues and tendons. Major mineral element content was determined in these tissues as well as in the noncarcass parts. In the lean tissue the mean content (200 kg) of 0.3 g calcium, 10 g phosphorus, 1 g magnesium, 2.3 g sodium and 14.8 g potassium/kg dry matter decreased slightly with rising live mass (200-650 kg). The contents of major mineral elements were much higher in bone tissue. For the fattening period from 200 to 650 kg of live mass mean contents of 151.5 g calcium, 71.3 g phosphorus, 3.2 g magnesium, 5.1 g sodium and 1.1 g potassium per kg DM were analysed. Mineral element content of bone tissue increased with rising live mass as well as animals on low feeding intensity showed a higher mineral content than on high energy level. In all, major mineral element content in fat tissue was very low. In noncarcass parts head and legs calcium and phosphorus had analogous to bone tissue the highest concentration. Hide showed a high content of sodium, whereas organs and digestive tract had a high content of potassium and phosphorus. Total mass of major mineral elements in the different tissues increased above all in the fattening period of 200 to 350 kg. In carcass as well as in empty body, mass of calcium and phosphorus was much higher than magnesium, sodium and potassium. Also animals on low feeding intensity showed a higher mass of major mineral elements in carcass and empty body than animals on high energy feeding intensity. The intensively fed bulls had a mean deposition of 12.7 g calcium, 6.9 g phosphorus, 0.37 g magnesium, 1.2 g sodium and 2.1 g potassium per 1000 g of empty body weight gain, whereas restrictively fed bulls deposited in average 15.0 g calcium, 7.8 g phosphorus, 0.4 g magnesium, 1.2 g sodium and 2.4 g potassium per 1000 g of empty body weight gain.

Animals↗

PubMed1995

[Food intake of dairy cows and heifers in late pregnancy during feeding of maize silage].

The influence of restricted (covering requirements) or ad libitum supply of maize silage in late pregnancy on feed intake was tested in two experiments with totally 51 dairy cows with several calvings (V1, V2 and in one experiment with 14 heifers (V3). Experimental time were the last 8 weeks before the expected calving date and was equivalent to the dry period of the cows. With adjusted feeding for energy requirement as a restricted supply the cows in V1 and V2 consumed 5.73 vs. 5.64 kg DM maize silage/animal and day, with ad libitum supply the intake of maize silage was substantial higher with an average of 9.65 vs. 9.85 kg DM/animal and day. With adjusted feeding for energy requirement as a restricted supply the heifers in V3 consumed 4.77 kg DM maize silage/animal and day. With ad libitum supply, however, the daily maize silage intake of heifers was substantial more with 7.00 kg DM/animal. With ad libitum feeding the mean daily intake of maize silage was unchanged in the weeks 8 to 3 before calving and decreased very strong in the cow experiments (V1, V2) in the last two weeks before calving and in the heifers experiment (V3) in the last week before calving. With restricted feeding the intake of maize silage was nearly unchanged until calving, only the cows in V1 showed a slight decrease in the last week before calving. With ad libitum feeding of maize silage in late pregnancy until 2 weeks before calving the cows and heifers reached a net energy intake of about 80 vs. 62 MJ NEL/day, which corresponded to 160% (V1, V2) vs. 135% (V3) of the energy requirement. The overconsumption for the crude protein was slighter with 120 to 140% of requirement.

Animals↗

PubMed1995

[Affection of growth of zinc deficiency growing rats].

Fifty male Sprague-Dawley rats with an average live mass of 42 +/- 4g were divided into 5 groups of 10 animals each. An artificial semi-systhesis diet was given to the animals. Group 1 received a control diet (32.2 mg Zn/kg DM), and group 2 a zinc deficient diet (3.4 mg Zn/kg DM) ad libitum. The animals of group 3 were pair fed to group 2 with a diet (84.9 mg Zn/KgDM). Diets of group 4 and 5 contained zinc (4.4 and 5.5 kg Zn/micrograms DM), respectively. The two groups also pair fed to group 2. The food intake and live mass gain were observed every day. After 26 days of experiment, the animals were decapitated; the blood samples were collected for the analysis of serum zinc, zinc binding capacity, and alkaline phosphatase.

Animals↗

PubMed1994

Effect of dietary hyperlipidemic components and fish oil on concentration of lipids in liver and liver fatty acid profile of rats.

This investigation was attempted to clarify the effects of dietary hyperlipidemic components and fish oil on concentration of lipids in liver and liver fatty acid profile of rats. In a first experiment male Sprague-Dawley rats were maintained on a semipurified low-fat diet with 6.5% coconut oil and 1.5% safflower oil, but without added cholesterol, or a high-fat hyperlipidemic diet supplemented with 7.3% coconut oil, 7.3% beef tallow, 0.4% safflower oil, and 1.5% cholesterol for 28 days. Rats fed the hyperlipidemic diet were then switched to fish oil diets with 1.4%, 2.8%, and 5.6% fish oil in exchange for coconut oil and beef tallow for, respectively, 10 and 20 days. In a second experiment male Sprague-Dawley rats were fed low-fat or high-fat diets without or with 1.5% added cholesterol for 28 days. Half of each group was then changed to a fish oil diet (for 20 days) which contained 5.6% fish oil in exchange for coconut oil and beef tallow. In experiment 1, rats fed the hyperlipidemic diet had enlarged fatty livers within 28 days. Experiment 2 showed that cholesterol in the diet was responsible for the accumulating liver lipids. Feeding diets with added cholesterol, the proportions of saturated fatty acids (SFA), especially 18:0, were markedly reduced in liver, whereas levels of monounsaturated fatty acids (MUFA) were greatly increased compared to diets without added cholesterol. This increase was most pronounced with respect to 16:1 and 18:1. In contrast, fish oil diets lowered MUFA level in liver in spite of its high MUFA content. Rats fed the highly saturated hyperlipidemic diet low in 18:2 n-6 had reduced 18:2 n-6 levels in liver compared to rats fed the low-fat diet without added cholesterol. Also, 20:4 n-6 level in liver was markedly reduced after the administration of the hyperlipidemic diet or the fish oil diets. Results of experiment 2 elucidate that cholesterol as well as fish oil sharply lowered 20:4 n-6 level in liver, which might be due to a reduced desaturation. In both experiments feeding fish oil increased all long-chain n-3 polyunsaturated fatty acids (PUFA) in liver. This occurred in a dose-dependent fashion and reached a maximum level with 5.6% fish oil in the diet. When additional cholesterol was applied 22:6 n-3 level in liver fell. This indicates also an impaired desaturation of PUFA due to dietary cholesterol.

Animals↗

PubMed1994

[Effect of isoenergetic replacement of starch by olive oil and fish oil concentrations of lipids in plasma and lipoprotein fractions in swine].

Two experiments with sows were performed to investigate the effect of isoenergetic replacement of starch by fish oil or olive oil on concentrations of lipids in plasma and lipoproteins. The first experiment was based on a cross-over design with three periods, each lasting 16 days. Each sow was fed during one of the periods a basal ration with isoenergetic addition of (1) starch (495 g/d), (2) olive oil (221 g/d), or (3) fish oil (223 g/d) based on energetic requirement for maintainance. The second experiment was based on a cross-over design with eight periods, each lasting 16 days. In the first and in the last periods, each sow was fed the basal ration. In the other six periods, each sow was fed the basal ration with addition of two different amounts of (1) starch (284/568 g/d), (2) olive oil (140/281 g/d), or (3) fish oil (141/282 g/d). The two different amounts of addition were selected to exceed the energetic requirement for maintainance by 25% or 50%. In both experiments blood samples were taken before each change of the ration. In both experiments olive oil elevated the concentration of cholesterol in plasma in comparison with starch. This elevation was due to a large elevation in high-density lipoproteins (HDL), and a slight elevation in low-density lipoproteins (LDL) and very-low density lipoproteins (VLDL). The ratio between HDL and LDL cholesterol was increased by feeding olive oil. The effect of olive oil on concentrations of cholesterol in plasma and lipoproteins was dose-dependent. In both experiments none of the two dietary oils significantly changed concentrations of triglycerides in plasma and lipoproteins. Concentrations of phospholipids in plasma, HDL, and LDL were elevated by olive oil. In both experiments addition of fish oil elevated concentration of cholesterol in plasma due to elevated cholesterol concentration in LDL. Concentration of HDL cholesterol was not changed by fish oil. Thus, the ratio between HDL cholesterol and LDL cholesterol was lowered by fish oil. The effect of fish oil on concentration of cholesterol in plasma and lipoproteins was also dose-dependent. Fish oil had no significant effect on phospholipid concentrations in plasma and lipoproteins. In conclusion, in the present experiment olive oil caused antiatherogenic changes of the lipoprotein profile, whereas fish oil caused proatherogenic changes of the lipoprotein profile.

Animals↗

PubMed1994

[The effect of zinc deficiency on heart and brain lipids in rats force-fed with coconut oil or fish oil diets].

The present study investigated the effect of zinc deficiency on lipid concentrations and fatty acid composition of heart and brain in force-fed rats receiving either a diet with coconut oil and safflower oil (86:14, w/w) or a diet with fish oil and safflower oil (91:9, w/w). Four groups of growing male Sprague-Dawley rats were fed 11.6 g of a semisynthetic diet containing either 0.8 mg Zn/kg or 111 mg Zn/kg with either coconut oil and safflower oil or fish oil and safflower oil per day by gastric tube for 10 days. Concentrations of lipids in heart as well as fatty acid composition of heart phospholipids and brain total lipids were determined. Zinc deficient rats fed the coconut oil diet had higher concentrations of triglycerides (16.3 mg/g vs. 9.21 mg/g) and total fatty acids (29.3 mg/g vs. 21.8 mg/g) in heart than control rats fed coconut oil diet, whereas concentrations of phospholipids and total cholesterol were not different between zinc deficient and control rats. Concentrations of lauric acid (12:0), myristic acid (14:0), palmitic acid (16:0), palmitoleic acid (16:1), and oleic acid (18:1) were by 65 to 192% higher in hearts of zinc deficient rats fed coconut oil diet than in control rats fed coconut oil diet. In contrast, concentrations of triglycerides, phospholipids, total cholesterol, and total fatty acids in heart were similar in zinc deficient rats and control rats fed fish oil diet. The fatty acid composition of heart phospholipids was only slightly influenced by zinc deficiency in the rats fed both types of dietary fat. The level of arachidonic acid in phospholipids which may represent desaturation activity was not different in the zinc deficient rats and control rats fed coconut oil diet, and was only slightly reduced in zinc deficient rats fed fish oil diet compared to control rats fed fish oil diet. This finding suggests that zinc deficiency does not impair delta-5 and delta-6 desaturation of linoleic acid in heart. Concentrations of fatty acids in brain as well as fatty acid composition of brain total lipids was only slightly influenced by zinc deficiency. This suggests that short-term zinc deficiency does not affect fatty acid metabolism of brain.

Alkaline Phosphatase↗

PubMed1994

The effects of dietary oils on the fatty acid composition and osmotic fragility of rat erythrocytes.

The present study was carried out to investigate the effect of different dietary oils representing special fatty acids which varied in chain length, position and number of double bonds on fatty acid composition of erythrocyte membranes and on the osmotic fragility of rat erythrocytes after incubation in NaCl solutions of different concentrations. For this purpose all animals were initially fed a control diet (CO) containing 10% coconut oil and 0.4% safflower oil for 28 days. After that 10 groups of 10 animals each were switched to test diets for another 20 days in which 50% or 100% of the coconut oil was exchanged for one of the following oils: olive oil (OO 5, OO 10), safflower oil (SFO 5, SFO 10), evening primrose oil (EPO 5, EPO 10), linseed oil (LO 5, LO 10) or salmon oil (SLO 5, SLO 10). The results show that the fatty acid composition of rat erythrocyte membranes was affected by the fatty acid composition of the dietary fats. Rats fed OO 10, EPO 10, LO 5 and LO 10 had a slightly lower concentration of saturated fatty acids (SFA) in erythrocyte membranes than control rats. Groups fed olive oil showed the highest level of monounsaturated fatty acids (MUFA) in the erythrocyte membrane. This increase in MUFA at the expense of SFA and (n-6) polyunsaturated fatty acids (PUFA) was most pronounced with respect to 18:1 and occurred in a dose-dependent fashion. Rats fed SFO, EPO or LO had higher linoleic acid levels in the erythrocyte membrane than control rats. This increase in 18:2 (n-6) was mainly at the expense of 18:1 and occurred in a dose-dependent fashion. The proportion of 20:4 (n-6) did not remarkably change feeding diets with (n-6) PUFA-rich oils. The (n-3) PUFA concentration in the erythrocyte membranes considerably increased, whereas (n-6) PUFA decreased feeding linseed oil or salmon oil rich in (n-3) PUFA. Linseed oil and salmon oil caused similar changes in the membrane, which were more pronounced in rats fed salmon oil than in rats fed linseed oil. The osmotic fragility of erythrocytes was also influenced by dietary oil, respectively fatty acid pattern of the erythrocytes. In almost all NaCl solutions erythrocytes from rats fed the dietary oils were less resistant to hemolysis than those from control rats. These changes became statistically apparent feeding EPO 5, LO 5, LO 10 and SLO 5.

Animals↗

PubMed1994

Levels of polyunsaturated fatty acids in tissues from zinc-deficient rats fed a linseed oil diet.

The effect of zinc deficiency on the levels of n-6 and n-3 polyunsaturated fatty acids (PUFA) in lipids from tissues of rats fed a diet containing linseed oil was investigated. Rats were fed either a control diet (25 mg Zn/kg) or a zinc-deficient diet (0.8 mg Zn/kg) for 10 d. To avoid energy and nutrient deficiency, 11.6 g of diet per day was administered by gastric tube. At the end of the experiment, rats fed the zinc-deficient diet had drastically reduced plasma zinc concentration and alkaline phosphatase activity consistent with severe zinc deficiency in these rats. Zinc-deficient rats had higher levels of n-3 PUFA, in particular eicosapentaenoic acid (EPA), and lower levels of n-6 PUFA, in particular linoleic acid, in liver and plasma phosphatidylcholine (PC) and in erythrocyte membrane total lipids than did control rats. By contrast, the levels of n-3 PUFA in PC from testes and heart, and in phosphatidylethanolamine (PE) from liver, testes and heart, were only slightly different between zinc-deficient and control rats. The study suggests that desaturation of alpha-linolenic acid is not inhibited by zinc deficiency, and that in zinc-deficient rats, n-3 PUFA preferentially incorporated into phospholipids at the expense of n-6 PUFA, especially EPA into PC. The study also shows that the effect of zinc deficiency on PUFA levels is different for PC and PE in rat tissues.

Animals↗