Different Levels Of Lipid Research Articles

Dietary Lipid Levels Affect Growth and Fatty Acid Profiles of Malaysian Mahseer Tor tambroides

AbstractAfter protein, the second major essential macronutrient in fish diet is lipid. This study was conducted to determine the optimum level of dietary lipid for the best growth performance of juvenile Malaysian mahseer Tor tambroides. Four isonitrogenous diets containing 40% crude protein were formulated to contain different levels of lipid (5, 10, 15, or 20% on an as‐fed basis). Cod liver oil was incorporated into the feed as the main dietary lipid source used to formulate the diets while residual oil coming from other ingredients contributed about 5% of dietary lipid. The experimental diets were labeled as L5, L10, L15, or L20 to denote the levels of dietary lipid. Fish were fed the experimental diets in triplicate groups for 63 d. Growth performance, survival rate, and daily feed intake by Malaysian mahseer significantly decreased when fed diets in which levels of dietary lipid increased from 5% to 20%. However, the growth performance did not vary significantly between fish fed the L5 and L10 diets. The increase in dietary lipid significantly increased the hepatosomatic index but did not influence the viscerosomatic index. Increasing dietary lipid levels also decreased the lipid content in the whole body composition of fish. The monounsaturated fatty acid (MUFA) and n‐3 polyunsaturated fatty acid (PUFA) contents of fish liver significantly increased with the increase of dietary lipid. The results of this study suggested that 5% dietary lipid is sufficient for the best survival rate and growth performance of juvenile Malaysian mahseer.

Influence of Dietary Glycyrrhetinic Acid Combined with Different Levels of Lipid on Growth, Body Composition, and Cortisol of Juvenile Channel Catfish, Ictalurus punctatus

Glycyrrhetinic acid (GA), the main active constituent of Glycyrrhiza glabra roots, is extensively used as food additives and herbal medicines. This study was carried out to evaluate the effects of different dietary levels of GA on growth and body composition of channel catfish (average weight, 1.10 ± 0.02 g). Eight diets were formulated to contain two levels of lipid (6.0 and 8.0%), and four levels of GA (0, 0.3, 0.6, and 0.9 g/kg). The experiments lasted for 60 d. Results showed that weight gain tended to decrease as dietary GA levels increased (P > 0.05) with the lowest found in fish fed 0.9 g/kg dietary GA (P < 0.05). Feed intake increased significantly as dietary GA concentrations increased up to 0.6 g/kg (P < 0.05) and viscera/body ratio, condition factor, hepatosomatic index, and intraperitoneal fat ratio decreased significantly as GA concentration increased (P < 0.05). Lipid content of whole body, viscera, and liver decreased significantly (P < 0.01) as dietary GA increased, whereas moisture content showed an opposite trend. The cortisol in fish fed 0.3 and 0.6 g/kg GA was not significantly higher than that of fish without GA supplementation, but glucose in the former two groups was higher (P < 0.05). Results of this study indicate 0.3 and 0.6 g/kg GA had a positive influence in reducing body lipid and IFR deposition in channel catfish without significant side effects on growth. The beneficial effect may be due to extending endogenous cortisol half‐life and increasing the duration of action.

The effects of dietary lipid levels on performance and heat-shock protein response of juvenile white seabass,Atractoscion nobilis

A feeding trial was conducted to study the effect of dietary lipid on growth performance and heat-shock protein (HSP70 and HSP60) response of white seabass (WSB), Atractoscion nobilis. Five diets were formulated to contain 440 g kg−1 protein from 300 g kg−1 fish meal, 240 g kg−1 soybean meal and 100 g kg−1 soy protein concentrate with different levels of lipid: 100, 120, 140, 160 or 180 g kg−1. At the end of the trial, heat shock response based on HSP70 and HSP60 was measured in liver and white muscle from fish at ambient temperature and temperature shock conditions. Final weight and percent gain were significantly higher for fish fed the 100 g kg−1 lipid diet than for fish fed the rest of the diets (P ≤ 0.05). Feed conversion ratio was lowest for fish fed the 100 g kg−1 lipid diet. The HSP70 and HSP60 responses were positively correlated to dietary lipid levels following temperature shock. At ambient temperature, HSP60 and HSP70 responses in muscle and HSP60 response in liver increased with dietary lipid level. Temperature shock significantly increased the HSP response of fish in all treatments. Results of this study demonstrated that a moderate (110–120 g kg−1) level of dietary lipids would be recommended for production diets but a higher dietary lipid level may be required for optimal stress tolerance.

Genetic and environmental influences on serum lipids and the effects of puberty: a Chinese twin study

To study the contribution of genes and environment on the variation of serum lipids and the effects of puberty. In total, 314 same-sex twin pairs aged 5-18 years were studied. Puberty was marked physiologically by spermarche/menarche, and model fitting was used to analyse the genetic and environmental variance and its difference before and after puberty. Lipid levels were different before and after puberty. The genetic factor had an important influence on lipid levels; the heritability estimates of total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), lipoprotein(a) (Lp(a)) and apolipoprotein E (ApoE) were between 49 and 86%. The total phenotypic variances of TC, HDL, LDL, Lp(a) and ApoE decreased after puberty, mainly as a result of decrease of genetic variance, even though the common environmental variance for HDL, Lp(a) and ApoE increased. Genes and the environment have different effects on the levels of different lipids. The shared environmental effects on lipids are very important in children. The role of puberty on lipids deserves future study.

Application of Hot-Melt Coating Process for Designing a Lipid Based Controlled Release Drug Delivery System for Highly Aqueous Soluble Drugs

Hot-melt coating process (HMCP) was applied to develop a lipid based oral controlled release matrix system (tablet) to deliver highly aqueous soluble drugs using paracetamol as a model drug. Granules prepared from paracetamol and particular filler were coated with different levels of lipid and then compressed into tablets to get controlled/sustained delivery of the drug over an optimum period. Process parameters were optimized with particular focus on fluidization pattern during HMCP proposing a 'design space' with 'Quality by Design' (QbD) concept in mind. The results demonstrated that the granule composition influenced the drug release pattern, and the rate of release could be manipulated by varying the amount of lipid in the formulation. The in vitro release profile of the drug was pH-independent and the most promising release profile was obtained from tablets prepared from granules with the water-soluble filler, lactose, and coated at 9% (w/w) level with a lipid, glyceryl behanate. In vivo plasma profiles of the drug were predicted from the in vitro release profile data by convolution analysis which confirmed that the lactose based formulation with 9% (w/w) lipid coating on the granules would be suitable for controlled delivery of the drug over a period of 12 h making the formulation suitable for highly water soluble drug candidates like paracetamol with twice daily dose regimen. Moreover, the dissolution data adequately fitted into Higuchi model suggesting that the drug release occurred predominantly by diffusion.

Effect of dietary taurine and lipid contents on conjugated bile acid composition and growth performance of juvenile Japanese flounderParalichthys olivaceus

The effects of dietary taurine levels and lipid contents on the conjugated bile acid composition and growth performance of juvenile Japanese flounder Paralichthys olivaceus were investigated. Six types of diet (three different levels of taurine at two different levels of lipid) were fed to juveniles (average body weight, 0.04g). Fishmeal that was washed with 70% ethanol to remove taurine was used as the sole protein source. Feeding experiments were carried out at 20°C for 6 weeks. At the end of the experiments, fish were weighed and analyzed for free amino acids in the body and the composition of the conjugated bile acids. The body weight and percent weight gain of the juveniles were improved by the dietary taurine supplementation. The taurine contents of the whole body and tissues increased with the increase of the dietary taurine contents. The conjugated bile acids in the gall bladder consisted of taurocholic acid and taurochenodeoxycholic acid, which increased with the increase of the dietary taurine level. Taurocholic acid accounted for more than 95% of the total conjugated bile acids. This indicates that taurine is the sole amino acid to conjugate bile acid in Japanese flounder.

Effects of dietary Iipid levels on growth performance and blood parameters of the African catfish {Cfarias gariepinus).

The African catfish (Clarias gariepinus) fed on diets containing different lipid levels (5%, 10%, 15% and 20%) at a feeding rate of 3% of the live body weight. Fish were reared in glass aquaria at a stocking rate of 10 fish at each aquarium. Each dietary Iipid level was presented in triplicates. The trial lasted for 90 days from the start. Ten fish were distributed in 100-L glass aquaria. Fish fed daily for 90 days in triplicate form. Results revealed that fish growth parameters as a final weight, weight gain, and specific growth rate were generally increased by increasing dietary lipid levels up to 10%, after which the growth rate was markedly decreased. Differences in feed intake among different treatments varied significantly (PO.05). Feed conversion ratio (FCR) was affected by dietary levels of lipids. No significant changes in survrval rate were observed due to the variation in dietary lipid levels. The highest values of the erythrocyte count (RBCS), hemoglobin content (Hb) and packed cell volume (PCV) were obtained in fish group fed on the diet containing 15% and 20% Iipid. Furthermore, mean corpuscular value (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) were changed in blood of fish fed on different levels of lipid. Glucose, total lipids, and total protein were significantly affected by increasing the lipid levels. Plasma total lipids and total protein were increased in fish with increasing lipid levels in the diets, Also, plasma AST and ALT activities increased significantly with increasing the level of lipids in fish diets, reaching the highest value in fish group fed diet with 20% lipids. The hepato-somatic index and gonado-somatic index of African catfish were significantly increased with increasing lipid level in fish diets. The present study demonstrated that the optimum dietary Iipid level was 10% for African catfish and there was no observed beneficial effect when fish was fed a diet containing 15% or 20% lipid levels.

Pengaruh Kadar Lemak Berbeda Terhadap Produksi dan Kualitas Telur Induk Ikan Nilem (Osteochilus hasselti)

The study was conducted on the effect of different levels of lipid in diet production and egg quality of Osteochilus broodstock reared in fiberglass. Broaders with 95 gram for females, were fed diets containing different levels of lipid, 4%, 6%, 8% and 10%. The protein contain of the diet for 42 %. The density of 20 females per fiberglass and daily fed ratio of 1.0 – 2.0% of body weight. The results indicated that all diet gave weight gain, fed convertion ratio, egg production, GSI, gonada weight and the containts protein and lipid of Osteochilus eggs were not significantly different (P>0.05). The eggs content completely amino, fatty and glutamic acids, histidine, proline, linoleic and linolenic acids, leads to good taste and delicious of eggs.

A prospective study of the association between APOE genotype and the risk of myocardial infarction among apparently healthy men

Background: Apolipoprotein E (apoE) plays an important role in lipid metabolism. Three common alleles in the APOE gene, E2/E3/E4, have been associated with lipoprotein disorders but their effects on myocardial infarction (MI) risk remain uncertain. Methods: In a prospective cohort of 14 916 apparently healthy men enrolled in the Physicians’ Health Study, APOE genotyping was conducted to determine three common alleles (E2/E3/E4) among 385 incident cases of first MI and among 373 age- and smoking-matched controls. Results: No significant differences in allele or genotype frequency for the APOE gene were detected between cases and controls. As expected, we observed significant positive associations between dyslipidemia (low HDL/high TG or high LDL) and MI risk ( P<0.001) and between genotypes and levels of LDL ( P<0.001), HDL ( P=0.04) or TG ( P=0.02). Compared with men homozygous for the E3 allele and after adjusting for multiple MI risk factors, men carrying the E4 allele (E4/4 or E4/3) had a relative risk of 0.93 (95% CI 0.63–1.37) and men carrying the E2 allele (E2/2 or E2/3) a relative risk of 1.03 (0.62–1.74). Moreover, no significant difference in MI risk was observed among different genotypes across different levels of lipids or smoking status. Conclusions: These data from a prospective study of apparently healthy men do not support the simple view of E2 as a protective factor and E4 as a susceptibility factor in predicting future risk of MI independent of lipid parameters. Nor did we observe any interaction between smoking and apoE4 allele on MI risk.

Movements of dietary triolein and cholestane in the digestive tract of prawnMarsupenaeus japonicus

In order to confirm the suitability of cholestane (CLS) for determination of lipid digestibilities in prawn, Marsupenaeus japonicus, the movements of dietary triacylglycerol and CLS in its digestive tract were examined. In this present study, the double labelling method was evaluated using [3H]-triolein and [14C]-CLS, which was chemically synthesized from [14C]-cholesterol. Three test diets containing different levels of lipid (0, 80 and 100 g kg−1 dry diet) with [3H]-triolein (150 MBq kg−1 diet) and [14C]-CLS (150 MBq kg−1 diet) were prepared. One prawn was stocked into a 1 L Erlenmeyer flask containing seawater at 25 °C. After the prawns had been fed on 1% of body weight of the labelled diets, they were transferred to another Erlenmeyer flask and held for 1, 3, 6, 12, 24, 36 and 96 h after feeding. At every collection time, radioactivity of the hemolymph, stomach, midgut gland, midgut, hindgut, muscle and faeces was determined by liquid scintillation counter. All analyses were performed in triplicate with one prawn per collection time per test diet. In the prawns administrated labelled diets, over 75% of the total radioactivity was recovered in faeces at 96 h after feeding. The ratio of [3H] to [14C] in the gastrointestinal tract of the prawn did not fluctuate for 96 h after feeding. Thus, triolein and CLS were shown to move at the same speed in the gastrointestinal tract. The results demonstrate that CLS satisfied one requisite for markers in the digestibility measurement of dietary lipids in the prawn.

Effects of dietary carnitine and lipid on growth and body composition of hybrid striped bass (Morone chrysops × M. saxatilis).

A study was undertaken to investigate the effects of graded dietary levels and different types of carnitine on hybrid striped bass (Morone chrysops ♀ × M. saxatilis ♂ %) fed different levels of lipid. An incomplete factorial design was utilized in which diets containing lipid at either 5 or 10% were supplemented with l-carnitine at 0, 500, or 1000 mg kg−1 diet, dl-carnitine at 1000 mg kg−1 diet, or carnitine chloride to provide 1000 mg carnitine kg−1 diet. Juvenile hybrid striped bass (3.3 g fish−1) were stocked into individual 38-l aquaria connected as a brackish water (6‰), recirculating system and fed each diet in triplicate for 9 weeks.

Response of juvenile freshwater prawn, Macrobrachium rosenbergii, to different levels of a cod liver oil/corn oil mixture in a semi-purified diet

Two separate experiments were conducted to determine the level of a dietary cod liver oil/corn oil (2:1, w/w) mixture needed for maximum weight gain of juvenile freshwater prawns, Macrobrachium rosenbergii. Seven isoenergetic and isonitrogenous purified diets with levels ranging from 0 to 12% in 2% increments were evaluated in each experiment that began with newly metamorphosed postlarvae. Diets used in the first experiment had protein and estimated digestible energy levels that were slightly higher than those used in the second experiment. After termination of both experiments, juveniles receiving the diet without the oil addition had significantly lower weight gains. Significant differences in weight gain responses to different levels of lipid were identified. Some relationships differed between experiments. Neither survival nor the time interval between molts was influenced by the level of the oil mixture. A dietary lipid level ranging from 2 to 10% under a wide range of dietary lipid:carbohydrate ratios appears to be satisfactory, indicating that juvenile freshwater prawns do not require a specific level of dietary lipid. Rather, the optimal amount of dietary lipid depends upon the amount and quality of dietary protein, the level of available dietary energy, and satisfaction of specific fatty-acid requirements.

Dietary effects on oocyte yolk-composition inCapitella sp. I (Annelida: Polychaeta): Fatty acids and sterols

In 1988, immatureCapitella sp. I (initial biomass 80µg dry wt) were raised on four diets: Gerber cereal, TetraMin fish food,Ulva sp., and benthic diatoms. After 2 wk of culturing different populations on these diets, eggs were dissected from gravid females, frozen and analyzed for fatty acid and sterol composition. Eggs produced by worms on different food types were discriminated by fatty acid composition in a principal component analysis (PCA), with 18:19, 18:2, 20:5 and 20:4 fatty acids showing the greatest differences between experimental groups. The sterol profiles of all eggs were dominated by cholesterol (cholest-5-en-3β-ol) and cholest-5,24-dien-3β-ol (>60%). A PCA of egg sterols discriminated between adult diets with cholesterol, 23,24-dimethyl-cholesta-5-en-3β-ol, cholest-5,24-dien-3β-ol and a C-29 stenol showing the greatest differences. In field populations ofCapitella sp. I, oocytes produced at different times of the year may have different levels of lipids depending on their dietary availability during vitellogenesis. Variations in oocyte composition may influence larval growth and development and thus have an impact on population dynamics. Alternatively, variations in fatty acid and sterol composition of oocytes may allow us to identify the food resources utilized by this species.