Added Corn Oil Research Articles

Effect of Altered Solvent Environment on the Pasting Characteristics of Pigeonpea (<i>Cajanus cajan</i>) and Cowpea (<i>Vigna unguiculata</i>) Starches

The (Brabender) pasting characteristics of pigeonpea and cowpea starches as a function of pH, sucrose concentration, added corn oil and legume protein isolates were investigated. Adjusting pH to 2 resulted in complete loss in paste consistency at 97°C for both starches. For pigeonpea starch, incorporation of corn oil and 10% sucrose resulted in significant (p J. agric. Sci. technol. Vol.5(1) 2003:80-90

Performance of Commercial Laying Hens when Six Percent Corn Oil Is Added to the Diet at Various Ages and with Different Levels of Tryptophan and Protein

Three experiments were conducted to evaluate the use of corn oil in the diet of commercial layers as a method of increasing egg weight. In the first experiment, the performance of commercial layers receiving 6% added corn oil beginning at 18 to 30 wk at 2-wk intervals was evaluated. In the second experiment, comparisons were made between performance of young and old commercial layers when 6% corn oil was added to the diet. The third experiment was conducted to evaluate the effects upon commercial layers when 6% corn oil was added to diets varying in Trp content.In experiment 1, egg weights increased during the first 2 wk that corn oil was added to the diet. During this time, the intake of Trp was greater than or equal to the hen requirements. However, during the last 2 wk of the experiment, when Trp intakes were low, egg weights decreased when corn oil was added to the diet. In experiment 2, egg weights from young and old hens increased during the first 2 wk after corn oil was added to the diet. During the last 2 wk, egg weights from young hens decreased, whereas egg weights from old hens increased. In experiment 3, egg weight was not affected when the diet contained 0.166 or 0.176% Trp. However, egg weights significantly increased when corn oil was added to the diet containing 0.193% Trp.The data in these experiments indicate that the diet of a laying hen must contain a high level of Trp to get an increase in egg weight from the addition of corn oil to the diet. Also the need for other amino acids must be met. Therefore, the hen eats to meet her energy requirement for maximum egg production, and her amino acid intake determines the egg weight.

볶음 과정중 첨가한 옥수수 기름이 마른 새우 향기성분 형성에 미치는 영향

건조새우를 볶는 과정 중에 옥수수기름의 첨가에 따른 향기성분변화를 검토하고자 건조새우와 건조새우 중량에 옥수수 기름을 각각 10%, 25%씩 첨가한 시료를 180℃에서 7분간 가열하였다. 마른새우 및 가열한 3개 시료의 향기성분을 연속수증기증류방법으로 추출하였다. 확인된 향기성분은 14개의 aldehyde와 pyrazine과 pyridine이 각 7개 그리고 5개의 alcohol과 3개의 pyrrole 등 총 52개이었다. 확인된 모든 성분중에서 그 함량과 향기성분의 수가 가장 많은 것은 aldehyde류 이었다. 기름을 첨가하여 가열한 시료에서는 지방산 사슬에서 기인된 heptenal, trans-2-heptenal, nonanal, trans-2-decenal, trans, cis-2,4-decadienal, trans, trans-2,4-decadienal과 1-octen-3-ol, 2-pentylfuran 등의 지질 분해산물이 관찰되었다. 새우의 독특한 향기성분을 나타내는 함질소 화합물인 pyrazine, pyridine, pyrrole 등은 마른 새우에서는 검출되지 않았으나 가열하여 볶은 새우에서 확인되었으며 옥수수 기름을 10 g 첨가하여 볶은 시료에서 그 함량이 가열한 시료보다 조금 더 증가하였으며 25 g의 기름을 첨가한 시료에서 가장 많이 나타났다. 이 결과는 첨가된 옥수수 기름에서 기인된 aldehyde류가 시료의 아미노산과 반응하여 바람직한 함질소 향기성분 생성에 기여한 것이라고 할 수 있다.

Effect of high-oil corn or added corn oil on ruminal biohydrogenation of fatty acids and conjugated linoleic acid formation in beef steers fed finishing diets.

Three Angus steers (410 kg) cannulated in the proximal duodenum were used in a replicated 3 x 3 Latin square to evaluate the effects of dietary lipid level and oil source on ruminal biohydrogenation and conjugated linoleic acid (CLA) outflow. Dietary treatments included: 1) typical corn (TC; 79.2% typical corn), 2) high-oil corn (HOC; 79.2% high-oil corn), and 3) the TC diet with corn oil added to supply an amount of lipid equal to the HOC diet (OIL; 76.9% TC + 2.4% corn oil). Duodenal samples were collected for 4 d following 10-d diet adaptation periods. Data were analyzed with animal, square, period, and treatment in the model and planned, nonorthogonal contrasts were used to test the effects of dietary lipid content (TC vs HOC and OIL) and oil source (HOC vs OIL) on ruminal biohydrogenation. Intake and duodenal flow of total long-chain fatty acids were increased (P < 0.05) by over 63% for diets containing more lipid regardless of oil source. Apparent ruminal dry matter and long chain fatty acid digestibilities were not altered (P > 0.05) by dietary lipid level or oil source. Ruminal biohydrogenation of total and individual 18-carbon unsaturated fatty acids was greater (P < 0.05) for diets with higher lipid content. Biohydrogenation of oleic acid was greater (P < 0.05) for HOC than OIL, but biohydrogenation of linoleic acid was lower (P < 0.05) for HOC than OIL. Duodenal flows of palmitic, stearic, oleic, linoleic, and arachidic acids were more than 30% greater (P < 0.05) for diets containing more lipid. Flow of all trans-octadecenoic acids was greater (P < 0.05) for diets containing more lipid. Corn oil addition increased (P < 0.05) the flow of trans-10 octadecenoic acid and the trans-10, cis-12 isomer of CLA by threefold compared to feeding high-oil corn. Feeding high-oil corn or adding corn oil to typical corn rations increased intake, biohydrogenation, and duodenal flow of unsaturated long-chain fatty acids. Compared with high-oil corn diets, addition of corn oil increased duodenal flow of trans-10, trans-12 and cis-12 isomers of octadecenoic acid and the trans-10, cis-12 isomer of CLA. The amount of cis-9, trans-11 isomer of conjugated linoleic acid flowing to the duodenum was less than 260 mg/d, a value over 20 times lower than flow of trans-11 vaccenic acid indicating the importance of tissue desaturation for enhanced conjugated linoleic acid content of beef.

Performance of Commercial Layers when Fed Diets with Corn Oil Added from 24 To 36 Weeks of Age

Six percent corn oil was added to the diet of a different group of commercial laying hens at biweekly intervals from 24 to 34 wk of age. A 2 × 7 factorial arrangement of treatments was used, which involved two houses with cold and warm temperatures and seven dietary treatments. The data were collected from each treatment for the entire experiment. The interaction of house × treatment was not significant; therefore, the data for the two houses were combined, and main effects are presented. The number of eggs weighing greater than 54.3 g increased significantly each time the corn oil was added to the diet. Egg weight was increased after corn oil had been added to the diet for 2 wk. Adding corn oil to the diet increased daily energy intake and body weight but did not affect egg production. The highest percentage of large and above eggs for the entire experiment was produced when corn oil was added at 26 wk of age.

Poultry Fat and Corn Oil May Be Used to Adjust Energy in the Diets of Young Breeder Hens Without Affecting Embryogenesis and Subsequent Broiler Growout Performance

Beginning at 22 wk of age, broiler breeder hens were fed one of six experimental diets. Diets 1 and 2 were fed to provide each bird an ME intake of 467 kcal/day (high) at peak production [467 peak Calories/day (PCD)], whereas Diets 3 and 4 contained low ME levels (430 PCD), and Diets 5 and 6 contained moderate ME levels (449 PCD). Diets 1 and 3 contained 3.0% added poultry fat, Diets 2 and 4 contained no added fat, Diet 5 contained 1.5% added poultry fat, and Diet 6 contained 3.0% added corn oil. Eggs were collected when hens were 29 wk of age. Embryonic mortality, hatchability, and subsequent growout performance were assessed through 42 d of broiler age. Added fat type (poultry fat or corn oil), poultry fat level (1.5 or 3.0%), or ME level from low (430 PCD) to high (467 PCD) in the diets of young (29-wk-old) breeder hens had no effects on subsequent embryogenesis, hatchability, or posthatch growout performance of broiler offspring. It was concluded that 1.5 and 3.0% added poultry fat or 3.0% added corn oil may be effectively used to adjustMEbetween low and high levels in the diets of young breeder hens without subsequent effects on broiler embryogenesis and growout performance.

Conjugated linoleic acid depresses the δ desaturase index and stearoyl coenzyme A desaturase enzyme activity in porcine subcutaneous adipose tissue

Conjugated linoleic acid (CLA) has been shown to have an effect on subcutaneous fatty acid composition and has been reported to decrease stearoyl coenzyme A desaturase (SCD) activity by decreasing mRNA expression and(or) catalytic activity in rodents and rodent cell lines. This investigation was designed to study the effects of CLA, corn oil, or beef tallow supplementation on s.c. adipose tissue fatty acid composition, adiposity, SCD enzyme activity, and the delta9 desaturase index in piglets. Eighteen crossbred barrows 16 to 18 d of age were adapted to diet for 1 wk and then assigned randomly to one of three treatments: 1.5% added CLA, 1.5% added corn oil, or 1.5% added beef tallow. Barrows were penned individually and fed the supplemental oils for 35 d (to 25.6 +/- 0.6 kg BW). Subcutaneous adipose tissue samples were obtained after slaughter. Fatty acid composition of the s.c. adipose tissue differed for each fatty acid measured due to diet with the exception of 18:3. The concentrations of CLA trans-10, cis-12 and cis-9, trans-11 were elevated from nondetectable to 1.62 and 2.52 g/100 g lipid, respectively (P < 0.001 for both isomers). Conjugated linoleic acid decreased the delta9 desaturase index (P < 0.01) and SCD enzyme activity, expressed as nanomoles of palmitate converted to palmitoleate/(7 min x g of tissue) (P = 0.075) and nanomoles of palmitate converted to palmitoleate/(7 min 105 cells) (P= 0.056). Tallow-fed pigs had a greater proportion of large adipocytes (> 700 pL) and the greatest SCD activity. These data provide the first direct evidence that dietary CLA depresses SCD enzyme activity in porcine adipose tissue, which may in part be responsible for the depression of adiposity by CLA observed by others in market weight pigs.

Market Age Live Weight, Carcass Yield, and Liver Characteristics of Broiler Offspring from Breeder Hens Fed Diets Differing in Fat and Energy Contents ,

The effects of energy level, fat type, and fat level in breeder hen diets on subsequent offspring market age live BW, carcass yield, and liver characteristics from breeder hens at 29 and 36 wk of age were evaluated. At 22 wk of age, six dietary treatments were imposed. Dietary treatments contained: 1) 3.0%, added poultry fat (PF) and 467 (high energy) kcal/hen per day at peak production (CPP), 2) no added fat and high energy, 3) 3.0% added PF and 430 (low energy) CPP, 4) no added fat and low energy, 5) 1.5% added PF and 449 (moderate energy) CPP, and 6) 3.0% added corn oil (CO) and moderate energy. Breeder age influenced Day 43 broiler live BW, percentage total carcass and front-half yields, and liver moisture contents. Furthermore, wet and dry liver weights were higher in female broilers compared to those of male broilers from 29-wk-old breeder hens. Live BW was higher in broilers from hens fed low-energy diets compared with moderate-energy diets and 3.0% compared to 1.5% PF diets. Percentage liver DM was higher in females compared to male broilers from hens fed 3.0% CO and moderate energy and was highest in male and female broilers from hens fed 1.5% PF and moderate energy. Percentage wet liver weight and liver DM were higher and liver moisture content was lower in broilers from hens fed 1.5% compared to 3.0% PF diets. Overall, energy and fat levels in breeder diets had subsequent influences on market age weight and liver characteristics of broilers.

Dietary Protein Restriction and Fat Supplementation Diminish the Acidogenic Effect of Exercise During Repeated Sprints in Horses

A restricted protein diet supplemented with amino acids and fat may reduce the acidogenic effects of exercise. Twelve Arabian horses were assigned to a 2 x 2 factorial experiment: two fat levels: 0 or 10 g/100 g added corn oil and two crude protein levels: 7.5 g/100 g (supplemented with 0.5% L-lysine and 0.3% L-threonine) or 14.5 g/100 g. The experiment began with a 4-wk diet accommodation period followed by a standard exercise test consisting of six 1-minute sprints at 7 m/s. Horses were interval trained for 11 wk followed by another exercise test with sprints at 10 m/s. Blood samples were taken at rest and during the exercise tests. Plasma was analyzed for PCO(2), PO(2), Na(+), K(+), Cl(-), lactate, pH and total protein. Bicarbonate, strong ion difference and total weak acids were calculated. Data were analyzed using repeated-measures analysis of variance. Venous pH was higher in the low protein group during the first test (P = 0.0056) and strong ion difference became higher (P = 0.022) during sprints in the low protein group. During the second test, venous pH and bicarbonate were higher for the low protein high fat group (P = 0.022 and P = 0.043, respectively) and strong ion difference became higher (P = 0.038) at the end of exercise in the low protein groups. These results show that restriction of dietary protein diminishes the acidogenic effect of exercise, especially in combination with fat adaptation.

Characterization of Lipoxygenase from Fungi of the Genus Mortierella

The specific activity of lipoxygenase from several strains of the zygomycete Mortierellavaried from 1.02 to 2.02 μmol diene per min per mg protein. The enzyme equally used linoleic or arachidonic acid as a substrate. An increase in lipoxygenase activity was observed after adding corn oil to the culture medium. Tests with inhibitors having different chemical structures revealed that the lipoxygenase activity from Mortierellacells was inhibited only by esculetin, ethanol, and nordihydroguaiaretic acid (NDGA). NDGA inhibited the enzyme in vitro(IC50=142 μM), but its addition in the exponential phase of growth activated the enzyme.

Comparative Effects of Phytosterols and Plant Oils on the Growth Depression in Chicks Fed Quillaja Saponin

To compare the effect of phytosterols (PS) and plant oils on the growth depression due to saponin, seven-day-old chicks were fed experimental diets for 10-12 days. A 0.6% Quillaja saponin in the diet depressed body weight gain, feed intake and gain/feed ratio. PS partly (0.1-0.2%) or completely (0.4 or 0.6%) counteracted the adverse effect of saponin. The effect of cholesterol (CHS) on saponin-fed chicks was compatible with that of PS. The alleviation in growth depression by both sterols was always accompanied by the increase in both feed intake and gain/feed ratio. PS also suppressed the elevated CHS concentrations in the serum and liver induced by the dietary CHS. Corn oil and coconut oil added to the saponin diet improved gain/feed ratio, but they failed to increase feed intake sufficiently. Consequently, the addition of plant oils was less effective than that of PS in alleviating the growth depressing-effect of saponin. Beef tallow, animal fat, showed the same effect on saponin-fed chicks as did plant oils. In addition, the beneficial effect of added corn oil or beef tallow disappeared when metabolizable energy of the diet containing oil or fat was equal to that of basal diet. Thus, the alleviative effect of plant oils seems to be attributed to the increase in the dietary energy rather than to the PS present in oils. In conclusion, increasing feed intake is necessary to improve the growth depression due to saponin.

Effects of breeder age and dietary fat on subsequent broiler performance. 2. Slaughter yield

The effects of breeder age (35, 51, and 63 wk) and added dietary fat on subsequent broiler slaughter yield were evaluated. Beginning at 22 wk of age, diets included 0, 1.5, or 3.0% added poultry fat (PF), 1.5 or 3.0% added corn oil (CO), or 3.0% added lard (LA). Slaughter yields were greatest in broilers from 63-wk-old breeders. Added CO in broiler breeder diets significantly increased subsequent 43-d live BW and chilled carcass yields compared to LA. Furthermore, CO diets significantly increased relative front-half yields compared to PF diets; and compared to the 3.0% fat level, 1.5% added fat significantly increased 43-d live BW, regardless of fat type. In conclusion, breeder age influenced broiler slaughter yield, and fat added at the 1.5% level to breeder hen diets was an effective energy source. However, less saturated fat improved subsequent slaughter yield.

Effects of breeder age and dietary fat on subsequent broiler performance. 1. Growth, mortality, and feed conversion

The effects of breeder age (35, 51, and 63 wk) and added dietary fat on subsequent broiler growth, mortality, and feed conversion through 42 d were evaluated. Beginning at 22 wk of age, diets included 0, 1.5, or 3.0% added poultry fat (PF), 1.5 or 3.0% added corn oil (CO), or 3.0% added lard (LA). Broilers from hens 35 wk of age performed better between 0 and 21 d than those from 51- and 63-wk-old hens. Conversely, between 22 and 42 d, broilers from hens 51 wk of age performed better than those at 35 and 63 wk. In relation to PF, CO added to breeder diets increased 0 to 21 d BW gain in broilers; whereas, feed conversion between 22 and 42 d was reduced in broilers from hens fed PF compared to those fed CO. In conclusion, breeder age influenced broiler performance differently throughout the growout period. Fat added at the 1.5% level to breeder hen diets was an effective energy source. However, less saturated fat improved growout performance.

Broiler breeder age and dietary fat influence the yolk fatty acid profiles of fresh eggs and newly hatched chicks

The purpose of the present study was to investigate the combined effects of breeder age (36-, 51-, or 64-wk) and different dietary fat sources (3% added corn oil, poultry fat, or lard) on lipids in fresh egg yolks and yolks of newly hatched chicks. Isocaloric breeder diets were altered by the inclusion of different types of dietary fat such that the poultry fat and lard diets had the highest levels of saturated fatty acids when compared to the corn oil diet. Fresh egg yolks obtained from 36-wk-old breeders exhibited higher levels of palmitoleic acid when compared to the levels observed in fresh egg yolks of 51- or 64-wk-old breeders. Furthermore, these levels decreased significantly by 21 d of incubation only in eggs from 36-wk-old hens. At 36 wk of breeder age, the levels of oleic and arachidonic acid were higher in yolks from hatched chicks than in previous fresh egg values, regardless of type of added dietary fat; whereas the level of linoleic acid was higher only in yolks from hatched chicks compared to those of fresh eggs from 36-wk-old hens fed 3% added corn oil. These data suggest that breeder age influences the utilization of yolk lipid by developing embryos, and that the type of fat provided in the diet may have an additional influence.

Broiler Breeders do not Respond to Added Corn Oil or Poultry Fat

Harms, R. H. and Russell, G. B. 1997. Broiler breeders do not respond to added corn oil or poultry fat. J. Appl. Anim. Res., 11: 157–162. An experiment was conducted with Arbor Acres breeder hens to study the influence of adding corn oil (CO) or poultry fat (PF) to the diet. The corn-soybean meal basal diet used contained .261, .556 and .103%, respectively of methionine, lysine and tryptophan. Two other diets were formed by the addition of 3% (CO) or (PF). Egg production, egg weight and egg content were not significantly different for the three diets. Hens fed diets with CO and PF gained more weight than fed the basal diet.

Effect of age, weaning and postweaning diet on small intestinal growth and jejunal morphology in young swine.

The effect of age, weaning and postweaning diet on small intestinal growth and morphology were investigated in young swine. Small intestine weight and villus height, measured at the midpoint of the small intestine (i.e., jejunum), were determined in suckling and weaned pigs. Scanning electron microscopy was performed on jejunal specimens from suckling pigs killed at 2, 10, 21, 28 and 35 d of age and in 21-d and 35-d weaned pigs at various ages postweaning. A 2 X 2 factorial arrangement of postweaning diets also was used to investigate jejunal morphological measurements in a 21-d-old weanling pig group. These dietary treatments evaluated the effects of 0 or 25% added dried whey and 0 or 6% added corn oil. The morphology results demonstrated that jejunal villus height declined during the suckling period, with a marked reduction at 3 and 7 d postweaning for both 21-d-old and 35-d-old weaned pigs. Transmission electron microscopy also demonstrated long, uniform microvilli on the jejunal villi in suckling pigs at 2 and 21 d, with markedly reduced lengths upon weaning. Jejunal villi were shorter in weaned compared with suckling pigs at the same approximate chronological age. Scanning electron microscopy in suckling pigs at 2 and 10 d of age demonstrated long, thin, fingerlike villi with subsequently reduced heights and larger diameters by 35 d of age. At weaning, villi were in close apposition, resulting in an overall smoother villus luminal surface. Villus height subsequently increased by 14 d postweaning, coinciding with the appearance of morphologically tongue-shaped villi. Starter diet composition initially did not influence the villus height reduction response postweaning. Dietary corn oil addition was subsequently associated with shortened villus length (P less than .05) during the starter phase.

Effects of dietary dried whey and corn oil on weanling pig performance, fat digestibility and nitrogen utilization.

Two experiments were conducted to evaluate the effects and interactions of dietary levels of corn oil (0 vs 6%) and dried whey (0 vs 25%) on performance of young pigs during a 4-wk postweaning period. The first experiment, conducted in five replicates as a 2 x 2 factorial in a randomized block design, evaluated gain and feed intakes of 172 pigs weaned at 21 d of age. Pigs were bled at weekly intervals, and samples were assayed for serum triglyceride and urea concentrations. In a second experiment, 36 barrows in three replicates were used to evaluate the same treatments on apparent digestibility and absorption of fat and N retention during each week of a 4-wk postweaning period. The dietary inclusion of dried whey resulted in greater gains and feed intakes and reduced feed-to-gain ratios during each week of the postweaning period, with the largest relative improvement occurring during wk 1. Supplemental corn oil did not enhance pig gains the first 3 wk postweaning, but response improved by wk 4. Feed intakes were slightly (P less than .10) lower when corn oil was provided. The inclusion of corn oil resulted in an improved feed-to-gain ratio (P less than .01), particularly evident during wk 3 and 4 postweaning. Neither gain nor feed utilization were improved by added corn oil during the initial 2-wk postweaning period regardless of dried whey addition. Apparent digestibilities of fat were unaffected at each weekly interval by dietary dried whey inclusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Zinc-amino acid complexes for swine.

Two experiments were conducted to determine the effect of sources of dietary zinc on gain, feed conversion and blood and bone traits of swine. In the first experiment 96 pigs were used in a 28-d study. The pigs were fed diets with no supplemental Zn or with either 9 or 12 ppm supplemental Zn from zinc sulfate (ZnSO4), zinc methionine (ZnMet) or zinc methionine with picolinic acid (ZnMet w/PA), each with or without 5% added corn oil. There were differences (P less than .05) in average daily gain (ADG) and average daily feed intake (ADFI) between the pigs fed the two organic Zn sources, with those fed ZnMet w/PA showing the better gains and feed conversion. However, neither organic Zn source resulted in pig performance that was different from either the diet with no supplemental Zn or the diets supplemented with Zn from ZnSO4. In the second experiment the same dietary Zn sources and treatments were fed as in Exp. 1 except that corn oil was deleted as a variable. No differences in ADG, ADFI, feed/gain (F/G) or in changes in serum Zn or Cu were observed among treatments during either the 21-d nursery or the 56-d growing periods. During the subsequent 56-d finishing period ADG and ADFI were greater (P less than .01) for pigs fed the Zn-supplemented diets than for those fed the diets without supplemental Zn. There were no differences among treatments in F/G during the finishing period. Zn content of bone ash was lower (P less than .01) in the non-Zn-supplemented pigs. These data suggest that the Zn sources used are of similar biological value and do not support the theory that picolinic acid aids Zn absorption.

Energy Utilization by the Broiler Chicken as Affected by Various Fats and Fat Levels

Two experiments were designed to investigate the effects of fat supplementation at different levels on energy utilization by the broiler chicken. In one experiment, finisher diets containing 2.5, 5.0, or 10.0% of added corn oil (CO), poultry oil (PO), tallow (T), or a commercial hydrolyzed animal-vegetable fat blend (HB) were fed. In the second experiment, starter diets containing 0, 2.5, or 7.5% added CO, PO or HB were fed. Metabolizable energy (ME) values were not controlled through formulation but were determined experimentally. Energy retention was measured by a slaughter technique, and metabolic energy losses were calculated as the difference between metabolizable energy intake and energy deposition in the carcass.Broilers that were fed PO, T, and HB failed to adjust feed intake to control caloric intake. They ate significantly more ME calories per day when these fat sources were fed, gained more, were fatter, and had a lower feed:gain ratio than broilers fed no added fat or lower levels of fat. Failure to regulate caloric intake when fats are added to diets may be a component of the “extra caloric” effect of fat.Broilers which were fed CO tended to regulate their caloric intake better than those which were fed PO, T, and HB. It was not determined if CO is less palatable than the other fat sources or if the unsaturated fatty acids metabolically regulate appetite. When CO was fed, broilers tended to have lower feed:gain ratios than when the other fats were fed. There was an indication that daily heat production was less when CO was fed, which would suggest a lower heat increment.Fatty acid analysis verified the efficient use of dietary fats for adipose deposition and suggested a disproportionately greater use of the unsaturated fatty acids for carcass lipids.

Dietary corn oil does not suppress the fructose induced increase in hepatic fatty acid synthesis

The effect of dietary glucose and fructose on hepatic and whole body fatty acid synthesis in the presence and absence of added corn oil in the diet was examined in mice. Fructose-fed mice have higher rates of hepatic but not extra-hepatic fatty acid synthesis in vivo than do those fed glucose. In addition, fructose based diets elicit higher hepatic activities of fatty acid synthetase (FAS) ATP citrate lyase (CL), malic enzyme (ME) and glucose-6-phosphate dehydrogenase (G6PD) than do glucose based diets. Glucokinase (GK) was higher in glucose fed than fructose fed mice. Acetyl CoA carboxylase (AcCx) was the same on both diets. Inclusion of 5% corn oil in the diets decreased the activities of hepatic AcCx, FAS, ME, G6PD and in vivo hepatic and extra hepatic fatty acid synthesis in glucose fed mice but did not inhibit these in fructose fed mice except for G6PD where the inhibition was less than in glucose fed mice. Thus fructose feeding lead to higher rates of fat synthesis and less sensitivity to inhibition by dietary fat than does glucose feeding.