Indian J. Anim. Res., 51 (4) 2017 : 687-693
AGRICULTURAL RESEARCH COMMUNICATION CENTRE
Print ISSN:0367-6722 / Online ISSN:0976-0555
www.arccjournals.com/www.ijaronline.in
Effect of long term supplementation with dietary lipids on growth and fatty acid composition of rabbit’s brain Doha Mustafa Al Nouri and Shaista Arzoo1* Department of Food and Nutrition Sciences, King Saud University, Riyadh-11495, Kingdom of Saudi Arabia. Received: 13-01-2016 Accepted: 01-11-2016
DOI:10.18805/ijar.v0iOF.7262
ABSTRACT The purpose of this study was to investigate the effect of long-term supplementation with dietary lipids on growth and fatty acid composition of rabbit’s brain. Soybean oil, fish oil, sesame oil, docosahexaenoic acid and arachidonic acid were fed to weanling rabbits for 100 days. The rabbits were decapitated and brain sample was removed, homogenized and fatty acid concentration was measured by gas chromatography. Dietary lipids had a distinct effect on growth rate only in males. Rabbits fed the fish oil diet showed the highest total -3 fatty acids and lowest -6/-3 ratios. Rabbits fed the DHA diet had highest total saturated fatty acids and lowest values of total MUFA, total PUFA, total -6, and total -3 in females. This study shows that -6/-3 ratios have tremendous effect on the fatty acid composition of rabbit’s brain. Effect of treatment was not significant among different gender except for total saturated, ARA, C20:1 and C16:0. FO, DHA and DHA+ARA groups showed the -6/-3 ratios within the recommended range. This study shows that fatty acid composition of brain can be modulated by dietary lipids and long-term supplementation of dietary lipids especially fish oil (FO) has very good effect on the fatty acid composition of rabbit’s brain. Key words: Brain, Docosahexaenoic acid, Fatty acids, Lipids, -6/-3 ratios. INTRODUCTION Lipids are the most important component of diet. Studies show that chemistry and function of brain can be influenced by the diet (Fernstrom, 2000). Lipids comprise 50-60% of dry weight of adult brain, particularly arachidonic acid (AA, 20:4 (-6)) and docosahexaenoic acid (DHA, 22:6 (-3)) acids (Sinclair, 1975). The importance of lipids in cell signaling and tissue physiology is established by many CNS disorders and injuries that involve deregulated metabolism (Adibhatla and Hatcher, 2007). Feeding has very important impact on quality of meat and body composition of non-ruminants species including rabbits, is influenced by the composition of diet (Oliver et al., 1997). To our knowledge, hardly any comparative study is available which shows effect of dietary consumption of vegetable, fish and microalgae oils on the fatty acid profile of rabbit’s brain. The purpose of this study is to investigate the long term effect of consumption of different dietary oil (vegetable, fish and microalgae oils) sources with varying -6/-3 PUFAs on the fatty acid profile of brain and to determine the role of gender response to the variations. MATERIALS AND METHODS Animals and Care: The experiment was conducted on fortyfive weanling (25 male and 20 female) New Zealand white rabbits (6-wk-old, weighing 500–1000 g), obtained from Experimental Animal Care and Experimental Surgery Center *Corresponding author’s e-mail:
[email protected]
at the Faculty of Medicine, King Saud University, Saudi Arabia. This study is in accordance with the Animal Ethics Committee of the College of Science, King Saud University. The rabbits were randomly divided by weight into five groups and individually housed in stainless steel cages under controlled temperature (25 ± 2 °C) and relative humidity (50±5%), with a 12-h light/dark cycle. Diets formulation and preparation: Basal diet was obtained from the Arabian Agricultural Services Company (ARASCO), Saudi Arabia; which was prepared as per rabbit feed specification (47152- Rabbit 18/14 Pellet, without fat). The experimental diets were prepared by adding the oil blend to the basal diet (70 g/kg diet) as follows: SBO diet - 70 g soy bean oil/kg diet FO diet - 50 g fish oil + 20 g soy bean oil SO diet - 50 g sesame oil + 20 g soy bean oil DHA diet - 50 g DHA oil + 20 g soy bean oil DHA/ARA diet - 25 g DHA oil + 25 g ARA oil + 20 g soy bean oil.
Oils were added into basal diet by spraying under pressure with continuous mixing during spraying. Fresh diets were mixed weekly to avoid oil oxidation and kept refrigerated at 4°C until fed. The diets provided 7% fat (70 g/ kg diet) which is adequate for growing rabbits (Reeves, 1997). The feed composition data are given as footnote to Table 1.
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Table 1: Fatty acid composition (g/100 g total fatty acids) of the experimental diets Experimental Diets1 Fatty acids2
SBO
Saturated fatty acids (SAT) C14:0 0.05 C16:0 5.87 C18:0 2.79 C20:0 0.38 Monounsaturated fatty acids (MUFA) C16:1 -7 0.02 C18:1 -7 C18:1 -9 24.33 C20:1 -9 0.23 -3 Polyunsaturated fatty acids (-3 PUFA) C18:3 ALA 7.09 C20:5 EPA C22:6 DHA -6 Polyunsaturated fatty acids (-6 PUFA) C18:2 LA 61.55 C18:3 GLA C20:4 ARA C22:4 DTA Total Total SAT 9.09 Total MUFA 24.58 Total -3 7.09 Total -6 61.55 Ratios -6/ -3 8.68 ARA/DHA -
FO
SO
DHA
DHA+ARA
0.09 1.96 1.75 -
0.03 10.16 6.04 0.59
2.51 18.94 1.95 0.19
22.910 8.370 1.150 0.240
0.12 1.04 11.35 1.31
0.12 35.40 0.15
0.67 7.33 0.02 0.07
0.550 5.060 4.990 ND
2.41 20.44 29.77
2.07 -
2.14 0.67 28.31
3.020 0.520 22.80
18.89 1.49 -
45.02 -
18.24 0.14 1.16 -
17.00 0.100 0.890 -
3.80 13.82 52.62 20.38
16.82 35.67 2.07 45.02
23.59 8.09 31.12 19.54
12.67 10.60 26.34 17.99
0.39 0.05
21.75 -
0.63 0.04
0.680 0.040
1
The basal diet contained the following (g/kg): Corn-150; barley-106; wheat bran-200; soy meal-162; limestone-2.8; alfalfa- 370.5; cholinechloride0.6; methionine powder-1; dicalcium phosphate- 5.1; vitamin and mineral mix-2. The experimental diet included SBO-soybean oil (control), FOfish oil; SO- sesame oil; DHA- DHA algae oil; DHA+ARA- DHA+ARA algae oils, 1:1 ratio). 2 SAT: saturated fatty acids: MUFA- monounsaturated fatty acid; PUFA-polyunsaturated fatty acids; ALA-alpha linolenic acid; EPA- eicosapentaenoic acid, DHA- docosahexaenoic acid; LA- linoleic acid; GLA- gamma linolenic acid; ARA- arachidonic acid, DTA-docosatetraenoic acid.
Growth: Body weight was recorded in the non-fed state at the beginning of study (initial weight) and at time before slaughter (final weight). Weight gain (final body weight (g) - initial body weight (g)) and growth rate (total weight gain (g) /100 days study period) was calculated. Sampling and sample storage method: After 100 days, rabbits were food deprived over-night; 10 ml of blood was collected from non-anesthetized rabbit via cardiac puncture in vacutainer heparinized tube and centrifuged for 8 min at 4 °C to obtain the plasma and was stored in an eppendorf tube at 4 °C for further analysis. Fatty acid analysis: Brain samples were homogenized at 4 °C (Bench top Homogenizer 300 DS PRO Scientific, Inc., Oxford, USA). Total lipids from 0.4 g of the homogenized tissue were extracted according to Folch et al., (1957). Extracted lipids and/or oil blend samples were trans methylated to obtain fatty acid methyl esters (FAMEs), using 14% boron trifluoride in methanol (Bligh and Dyer, 1959). FAMEs were separated by gas chromatography (GC Clarus 500, Perkin Elmer, Shelton, USA), using an Omegawax™
320 capillary column (30 m × 0.32 mm i.d × 0.25 m film thickness, Supelco, Inc., Bellefonte, USA) at oven temperature, 200 °C; carrier gas, helium 25 cm/s at 200 °C; detector, flame ionization (FID) 260 °C; injection, 1 l split 100:1 at 250 °C. FAMEs from brain samples and oil blends were identified by comparison with retention times of standard fatty acids (Supelco, Inc., Bellefonte, USA) PUFA2, animal source, and FAME Mix RM-1, Oil Reference (Sigma–Aldrich, St. Louis, USA), respectively. Statistical analysis: Data were analyzed using SPSS statistical software package (version 22) and expressed as mean ±standard deviation. The differences among dietary treatment groups were analyzed by ANOVA at a significance level of P 0.05; if significant differences were found, Posthoc analysis using Duncan’s multiple range tests was performed. RESULTS AND DISCUSSION Fatty acid profile of formulated diet: The fatty acid profile of formulated diet is shown in Table1. Analyzed total saturated fatty acid value for the formulated dietary treatment
Volume 51 Issue 4 (2017) was highest for DHA and lowest for FO group. The SO diet had highest -6/-3 ratio and FO diet had lowest -6/-3 ratio and contained highest amount of EPA and DHA. Whereas the SBO diet had an intermediate -6/-3 ratio and contained highest amounts of LA and ALA. Total MUFA was highest in SO diet and lowest in DHA. SBO, SO and FO diets were devoid of GLA and DTA was not observed in any treatment. Similarly SBO and SO diets were devoid of ARA, EPA and DHA respectively. Growth: The growth of male rabbits was significantly (P 0.05) affected by dietary treatment. Long term dietary supplementation with various dietary lipids had a distinct effect on final body weight; weight gain and growth rate (Fig. 1. A and B). These growth indicators were significantly (P 0.05) higher in SBO and SO groups and significantly (P 0.05) lower in DHA group. It has been revealed previously that, the fat supplement in the diet reduces the feed intake, improves the fat conversion rate, but has no effect on growth rate (Fernandez et al., 1994). Decreased food intake might be the reason for the reduction in growth of rabbits fed with DHA diet. Previously dietary lipids were found to be ineffective on growth indicators in male rabbits (Sirosis et al., 2003) which might be related to short duration (15-63 days) of the study period. Other reasons might be related to the type, amount and variations in oil blends used in various studies. In this study, diets showed no effect on
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growth of female rabbits. This result is in agreement with previous study (Sirosis et al., 2003). However, further studies are required to know the mechanism for having significant differences in growth indicators of male rabbits but not in female rabbits using similar diet. Fatty acid profile of rabbit’s brain: Effect of treatment on fatty acid profile of rabbit’s brain has been shown in Table 2 and Fig 2. Compared to SBO (control group), rabbits fed the FO diet had highest C18:1 (-9), total MUFA, total PUFA, total -3, C22:6 (-3) in both males and females, highest value of C18:3 (-3) in males and C16:0, C18:0 and total saturated fatty acids in females and lowest value of C20:4 (-6), C22:4 (-6) and total -6 in males. It also shows lowest value of -6/-3 and ARA/DHA ratios (Fig 2) as compared to all other groups. SO diet had highest value of C18:3 (-6), C22:4 (-6), -6/-3 and ARA/DHA ratios and lowest value of C14:0 in both males and females. Male rabbits fed the SO diet showed the highest total -6 and 3 and lowest C16:0 and C22:6 (-3) in males and highest C20:1 (-9), C20:4 and ARA/DHA in females. Rabbits fed the DHA diet had lowest value of C18:1 (-7) in both males and females. It shows highest value of C16:0, C18:0, C20:4 (-6) in males and C18:3 (-3) and C20:4 (-6) in females respectively. It also shows lowest value of C18:3 (-6), C20:1 (-9), C20:5(-3) in males and C16:0, C16:1 (-7), C18:1 (-9), C20:4 (-6), C22:4 (-6), C22:6 (-3), total
Fig 1: Growth indicators of males and females rabbits fed with different dietary oil sources . Data are expressed as mean ± standard deviation. SBO-soybean oil (control); FO-fish oil; SO- sesame oil; DHA- DHA algae oil; DHA+ARA- (DHA+ARA algae oils, 1:1 ratio). a-e small letters indicate significant difference among dietary treatment groups for each gender separately as indicated by ANOVA followed by Duncan’s multiple range test (a>b>c>d>e).
Female
0.374 a ±0.172 12.132b ±4.265 0.392a ±0.255 4.396 a ±6.840 16.233b ±1.611 4.989b ±0.188 2.162c ±0.467 0.049 a ±0.047 0.123ab ±0.028 1.145ab ±0.341 6.666bc ±1.430 0±0a 2.382b ±0.882 2.391a ±1.848 19.882b ±9.959 22.76 b ±3.597 37.40a ±4.909 11.83 bc ±2.527 2.808a ±2.141 2.161a ±1.669 1.226a ±1.068
Male
4.022a ±8.225 17.768a ±14.132 0.71 a ±0.464 1.469a ±0.724 9.199a ±8.082 6.048a ±3.655 2.028 b ±1.081 0.024a ±0.053 0.251a ±0.237 0.897 a ±0.716 6.359 a ±1.970 0.065a ±0.114 2.162bc ±1.006 1.718 a ±1.269 23.20 ab ±13.974 16.855a ±8.046 29.460a ±12.928 10.573ab ±4.899 2.043a ±1.705 2.348a ±1.684 1.531a ±1.079
SB0 Male 0.216a ±0.060 16.793a ±2.575 0.452a ±0.102 13.618b ±5.828 17.377b ±1.781 4.076a ±0.344 1.984b ±0.279 0.527a ±0.909 0.212a ±0.103 0.671a ±0.616 7.874a ±1.196 0a ±0 2.84c ±0.885 1.494a ±0.767 34.060b ±5.002 23.038a ±2.396 37.52a ±2.056 12.78 b ±1.349 1.698 a ±1.018 9.507a ±12.786 2.935a ±1.853
SO Female 0.270 a ±0.111 14.822b ±3.384 0.331a ±0.142 16.514b ±0.444 17.493b ±2.407 3.223a ±0.937 1.922c ±0.197 0.188a ±0.194 0.157b ±0.158 1.357 b ±0.292 7.798 c ±0.663 0.014a ±0.012 3.414b ±3.705 1.861a ±0.723 31.606c ±3.681 22.410b ±1.907 38.246a ±2.216 13.143c ±1.1552 2.694a ±0.424 5.014b ±1.105 3.258b ±0.845
Male 4.322a±4.445 17.653a ±3.921 0.260a ±0.075 18.459b ±3.820 21.044b ±4.943 3.19a 0±0.953 0.864ab ±0.259 0a ±0 0.107a ± 0.062 0.669a ±0.411 5.953a ±1.937 0a ±0 0.181a ±0.403 5.856a ±2.989 40.441a ±11.458 25.159 a ±5.074 38.140 a ±7.892 7.017a ±2.413 5.963a ±5.148 4.868a ±6.501 5.834a ±8.761
FO 0.311a ±0.065 18.905b ±1.530 0.311a ±0.065 21.517b ±0.928 25.274c ±3.439 3.774b ±1.771 1.194b ±0.330 0a±0 0.09 ab ±0.138 1.093ab ±0.473 3.553ab ±0.157 0a ±0 0a ±0 5.208a ±0.257 40.733a ±3.406 30.422c ±3.435 40.378a ±5.802 4.649a ±3.754 5.305a ±5.332 1.399a ±0.694 0.717 a ±0.213
Female
Female 0.315a ±0.445 2.679a ±3.157 0.232a ±0.328 8.107a ±10.833 9.498a ±12.800 1.863a ±2.635 0.687a ±0.340 0a ±0 0.223a ±0.316 0.696a ±0.983 1.577a ±1.599 0 a ±0 0.415a ±0.587 1.329a ±1.879 16.380c ±19.229 12.363a ±14.804 16.669b ±17.351 2.754a ±2.660 1.552a ±2.544 0.797a ±0.978 0.188a±0.375
DHA 0.326 a ±0.250 22.141a ±7.675 0.37a ±0.312 19.884b ±5.456 16.763b ±4.751 2.830a ±1.775 1.183ab ±0.707 0.0162a ±0.036 0.151a ±0.116 0.330a ±0.499 9.237a ±1.782 0.024 a ±0.053 0.75a ±0.386 4.687a ±2.637 42.345b ±19.679 20.309 a ±7.420 35.338a ±11.758 10.165ab ±3.786 4.864a ±4.907 0.651a ±0.564 0.475 a ±0.416
Male
Dietary treatment1
Female
0.548 a± 0.014 0.275a ±0.189 19.399 a ± 4.115 16.82b ±4.718 0.223 a ± 0.127 0.449a ±0.290 17.532b ± 0.289 19.365b ±2.124 19.176b ± 0.387 19.505b ±0.136 3.835a ± 0.071 5.995b ±2.057 0.446a ± 0.128 0.541ab ±0.304 0 a ±0 0.025 a ±0.05 0.22a ± 0.009 0.062ab ±0.074 0.496a ± 0.136 1.049 ab ±0.581 7.346a ± 2.687 6.913bc ±2.337 0a ±0 0a ±0 1.116ab ± 0.193 1.249 a ±0.131 3.348a ± 0.049 3.213a ±1.037 37.480ab ±9.441 36.460 c ±7.696 23.681a ±5.079 25.843bc ±3.958 36.162a ±0.633 37.716 a ±4.867 8.910 ab ±0.662 8.878b ±3.362 3.571a ±5.051 2.994a ±3.802 0.656 a ±0.928 1.380a ±2.367 0.466 a ±0.659 1.13 a ±2.150
Male
DHA+ARA
Data are expressed as mean± standard deviation. SBO-soybean oil (control); FO-fish oil; SO- sesame oil; DHA-DHA algae oil; DHA+ARA- (DHA+ARA algae oils, 1:1 ratio). a-e small letters indicate significant difference among dietary treatment groups for each gender separately as indicated by ANOVA followed by Duncan’s multiple range test (a>b>c>d>e). 2 Total sat-total saturated fatty acids, MUFA-Monounsaturated fatty acids, PUFA-Polyunsaturated fatty acids, ARA- Arachidonic acid, EPA-Eicosapentaenoic acid, DHA-Docosahexaenoic acid.
1
C14:0 C16:0 C16:1( -7) C18:0 C18:1( -9) C18:1( -7) C18:2( -6) C18:3(ù -6) C18:3(-3) 20:1( -9) 20:4( -6) 20:5( -3) 22:4( -6) 22:6( -3) Total Sat Total MUFA Total PUFA Total -6 Total -3 -6/-3 ARA/DHA
Fatty acids2
Table 2. Effect of treatments on the fatty acid profile of brain of rabbits.
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Fig 2: -6/-3 and ARA/DHA ratios of males and females rabbits fed with different dietary oil sources. SBO-soybean oil (control); FO-fish oil; SO- sesame oil; DHA- DHA algae oil; DHA+ARA- DHA+ARA algae oils, 1:1 ratio). M-male and F-female
MUFA, total PUFA, total -6, total -3 in females. Rabbits fed the DHA+ARA diet had lowest value of C18:2 (-6) in both males and females and highest value of C16:1 (-7) and C18:1 (-7) in females. This diet also resulted in lowest value of C16:1 (-7), C20:1 (-9) in males and C18:3(-6), C18:3 (-3) fatty acids in females, respectively. However the rabbits fed the control diet had highest C18:2 (-6) and lowest C18:0 in both males and females, highest C16:1 (7), C18:1 (-7), C20:1 (-9) and C20:5 (-3) in males and highest total -6 in females respectively. It also shows lowest total saturated fatty acid, total MUFA and total PUFA in males. Effect of treatment was not significant among different gender except for total saturated, ARA, C20:1 and C16:0. Brain is well protected organ and fatty acid composition of brain has been reported to be broadly modulated by dietary lipids (Angulo-Guerrero and Oliart, 1998). Palmitic acid contributed to the major part of saturated fatty acid and myristic acid showed the least concentration in all treatments. Palmitic acid is most abundant saturated fatty acids in human diet. There were no significant (P 0.05) differences in the percentage of stearic acid, oleic acid or palmitoleic acids of brain between the experimental and control diet groups except, for DHA in females. A study was conducted by Suzuki et al. (1998) on rats fed sardine oil and palm oil did not found any significant difference in the percentage of stearic, oleic or palmitoleic acids of phospholipids in brain between experimental groups. This study showed that various dietary oil sources differing in their -6/-3 ratios significantly (P 0.05) altered the fatty acids level of brain; moreover brain fatty acid profile reflected the dietary level of -6 and -3 fatty acids fed to rabbits. Fatty acid composition including chain length, extent of unsaturation, and relative concentration of
the specific lipid moieties determines the extent to which dietary lipids affect cell structure and metabolism (Barjanti et al., 1994). Saturated fatty acids and MUFAs are synthesized in vivo and are not much influenced by the diet than PUFA such as linoleic acid and alpha linolenic acid which to some extent reflect the dietary profile of oil (Enser et al., 2000). Rabbits fed the FO diet (lower in -6/-3 ratio and higher in DHA) maintained lower -6/-3 ratios and higher DHA concentrations in their brain. Similarly in a previous study, rats fed on fish oil diet have shown an increase in DHA level and decrease in ARA and docosapentaenoic acid level of brain phospholipids (Galli et al., 1971). Rabbits fed the SO diet (higher in -6/-3 ratio) maintained higher -6/ -3 ratio. Those fed the SBO control diet (higher in LA and ALA) maintained higher LA and ALA concentrations in brain. As the amount of dietary 18:3 (-3) increased, level of 18:2 (-6) increased, whereas those of C20:4 (-6) was reduced in brain of rabbits. A similar trend was observed in previous study in rats (Anding and Hwang, 1986). The -6/ -3 ratio in FO, DHA and DHA+ ARA was found to be within the recommended range (less than 4). The composition of biological tissues can be altered through diet, either by direct incorporation of the absorbed compounds, or by their interactions with anabolic and catabolic pathways. If -6/ -3 ratio of diet is reduced, this generates eicosanoids with more beneficial effects in some chronic diseases than those derived from -6 fatty acids (Siddiqui et al., 2008). An indirect relationship was observed between -6/-3 ratio and the concentration of total omega 3 fatty acids, i.e. highest concentration of total -3 was found for the group (FO) having lowest concentration of -6/-3. This study confirmed that different dietary oil sources with varying -
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6/-3 ratios significantly altered the fatty acid profile of brain. EFAs, particularly -3 long chain polyunsaturated fatty acids (LCPs) are crucial for brain development in humans. Omega-3 deficient rats exhibited poor learning and memory performances in variety of tests, such as Mori’s Water Maze (Wainwright, 2002). In a study; the effects of four different diets i.e 5% peanut oil, cod liver oil, partially hydrogenated palm oil, and a mixture of peanut and rapeseed oil on phospholipids fatty acid composition of rat brain plasma membranes were evaluated. Animal fed the total PUFA deficient diet (palm oil) had significantly lower body and brain weight, lower brain cholesterol and phospholipids than the control group (peanut+rapeseed) whereas the brain of animals fed the -6 PUFA (cod) deficient diet had higher levels of these lipids components than the control group (Angulo- Guerrero and Oliart, 1998). In the present study, the concentration (not mentioned in table) of ARA was negatively correlated with EPA (-0.096), but positively correlated with DHA (0.055). Croft et al., (1988) reported antagonistic effect of EPA on ARA in rats’ leukocytes. The ratio of ARA to -3 PUFAs (EPA and DHA) in human diets is also an important factor (Molnar, 2012). Although the issue whether dietary ARA is harmful or not is unequivocal since ARA has both pro and antithrombotic and inflammatory effects (Netleton, 2008). Rabbits fed SBO or SO diets containing LA had higher levels of LA and ALA, in brain, in contrast to those fed FO, DHA or DHA/ARA diets supplemented with ARA, EPA and DHA had higher level of these fatty acids in brain compared to SBO and SO groups. LA and ALA in meat are mostly affected by diet because other fatty acids can be synthesized in the body of rabbits. The concentrations of ARA, EPA and DHA found in tissue phospholipids are the net result of the rates
of endogenous synthesis from LA and ALA and the amount of preformed ARA, EPA and DHA in the diet (Innis, 2000). In a previous study it has been shown that the concentration of alpha- linolenic acid in the diet and adipose tissue may not be strongly correlated especially when the level in the diet is very low (Mitchaothai, 2007). Results from the present study showed that supplementation with high concentration of DHA from fish oil resulted in increased DHA in brain. In addition to evidence that DHA may influence brain and development through effects on gene expression, monoaminergic neurotransmission or protection against apoptoptic cell death, growth of neurite processes from the cell body is critical step in neuronal development and involve large increase in cell membrane surface area (Innis, 2007). CONCLUSION The current study clearly demonstrated that long term supplementation of dietary lipids has tremendous effect on the fatty acid profile of brain. Effect of treatment was not significant between the genders except for total saturated, ARA, C20:1 and C16:0. The -6/-3 fatty acid ratio in FO, DHA and DHA+ARA was found to be within the recommended range. The concentration of ARA was negatively correlated with EPA and positively correlated with DHA. This study shows that long term supplementation of dietary lipids especially fish oil has very good effect on the fatty acid profile of rabbit’s brain. However, more studies are required for the concentration and types of fatty acid to obtain the beneficial therapeutic use. ACKNOWLEDGEMENT This research project was supported by a grant from the “Research Center of the Female Scientific and Medical Colleges”, Deanship of Scientific Research, King Saud University.
REFERENCES Adibhatla, R.M. and Hatcher, J.F. (2007). Role of Lipids in Brain Injury and Diseases. Future Lipidol. 2: 403–422. Anding, R.H. and Hwang, D.H. (1986). Effects of dietary linolenate on the fatty acid composition of brain lipids in rats. Lipids. 21:697-701. Angulo-Guerrero, O. and Oliart, R.R. (1998). Effects of dietary polyunsaturated fatty acids on rat brain plasma membrane fatty acid composition. Arch Latinoam Nutr. 48:287–92. Barjanti, V., Battino, M., Baracca, A., Cavazzoni, M,, Cocchi, M., Noble, R., Maranesi, M., Turchetto, E. and Lenaz, G. (1994). The effect of dietary lipid changes on the fatty acid composition and function of liver heart and brain mitochondria in the rat at different ages. Brit J Nutr.71: 193-202. Bligh, E.G. and Dyer, W.J. (1959). A rapid method of total lipid extraction and purification. Can J Biochem Physiol. 37: 911-917. Croft, K.D., Codde, J.P., Barden, A., Vandongen, R. and Beilin, L.J. (1988). Effect of dietary fish oils on the formation of leukotrienes B4 and B5, thromboxane and platelet activating factor by rat leukocytes. Clin Exp Pharmacol Physiol.15: 517-525. Enser, M., Richardson, R.I., Wood, J.D., Gill, B.P. and Sheard, P.R. (2000). Feeding linseed to increase the n-3 PUFA of fork: fatty acid composition of muscle, adipose tissue, liver and sausages. Meat Sci. 55: 201-212. Fernandez, C., Cobos, A. and Fraga, M.J. (1994). The effect of fat inclusion on diet digestibility in growing rabbits. J Animal Sci. 72:1508-1515. Fernstrom, J.D. (2000). Can nutrient supplements modify brain function? Am J Clin Nutr. 71:1669–1675.
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