Metabolic response of the gastrointestinal tract and serum parameters of rabbits to diets containing chicory flour rich in inulin

A 36-day experiment carried out on 54-day-old rabbits addressed the analysis of physiological properties of diets supplemented with chicory roots flour. Twenty-four rabbits were allocated in individual cages to three treatments, in which they were fed each diet with the chicory flour at 0, 25 and 50 g/kg (control, ChF(2.5) and ChF(5) groups respectively). The chicory preparation administered at a higher dose, lowered ileal pH and viscosity, and evoked increased hydration of ileal and caecal digesta, compared to the control treatment (p 相似文献   

Early introduction of an inert diet and unenriched Artemia enhances growth and quality of Atlantic cod (Gadus morhua) larvae

The effects of two weaning diets and different weaning protocols on growth, survival, skeletal deformity and gut morphology of Atlantic cod larvae were studied in four groups from 16 to 45 days posthatch (dph). Cod larvae in groups 1 (early weaning with control diet) and 2 (early weaning with experimental diet) were used to evaluate the effects of different polar lipid content of weaning diets on larval and juvenile performance. Cod larvae in groups 2, 3 (early weaning with experimental diet + cofeeding with Artemia) and 4 (earlier weaning with experimental diet and earlier cofeeding with Artemia) were used to evaluate the effects of early introduction of dry diet and Artemia. From 45 to 170 dph, cod juveniles from all four groups were reared using a standard feeding protocol. No significant differences in growth, survival, deformities and gut morphology were found between cod larvae and juveniles from groups 1 and 2. Cod larvae fed on cofeeding regime with Artemia nauplii (groups 3 and 4) were bigger and had lower frequencies of jaw and neck deformities and higher foregut microvillus circumference than cod larvae from group 2. Our results demonstrate the importance of proper weaning protocols in producing better quality cod juveniles.     

Modification of tissue fatty acid composition in Murray cod (Maccullochella peelii peelii, Mitchell) resulting from a shift from vegetable oil diets to a fish oil diet

The dynamics of fatty acid composition modifications were examined in tissues of Murray cod fed diets containing fish oil (FO), canola oil (CO) and linseed oil (LO) for a 25‐week period and subsequently transferred to a FO (finishing/wash‐out) diet for a further 16 weeks. At the commencement of the wash‐out period, following 25 weeks of vegetable oil substitution diets, the fatty acid compositions of Murray cod fillets were reflective of the respective diets. After transfer to the FO diet, differences decreased in quantity and in numerousness, resulting in a revert to the FO fatty acid composition. Changes in percentages of the fatty acids and total accumulation in the fillet could be described by exponential equations and demonstrated that major modifications occurred in the first days of the finishing period. A dilution model was tested to predict fatty acid composition. In spite of a general reliability of the model (Y=0.9234X+0.4260, R²=0.957, P<0.001, where X is the predicted percentage of fatty acid; Y the observed percentage of fatty acid), in some instances the regression comparing observed and predicted values was markedly different from the line of equity, indicating that the rate of change was higher than predicted (i.e. Y=0.4205X+1.191, R²=0.974, P<0.001, where X is the predicted percentage of α‐linolenic acid; Y the observed percentage of α‐linolenic acid). Ultimately, using the coefficient of distance (D), it was shown that the fatty acid composition of fish previously fed the vegetable oil diets returned to the average variability of the fillet fatty acid composition of Murray cod after 70 or 97 days (LO and CO respectively).     

南极磷虾粉脂质及脂肪酸组成分析

为分析南极磷虾粉的脂质成分,实验采用薄层层析法分离制备不同脂质组分,通过酸甲酯化衍生结合气相色谱/质谱法对不同脂质的脂肪酸组成进行比较研究.结果显示:①南极磷虾粉中脂质丰富,总脂含量高达11.37％,且以甘油三酯、磷脂和游离脂肪酸为主,胆固醇含量较低;②总脂脂肪酸主要为C16:0、C18:1n-9、C18:1n-7、C20:5n-3和C22:6n-3,且C20:5n-3和C22:6n-3占总脂肪酸含量的30.67％,表明南极磷虾粉在脂质方面具有较高的营养价值和开发潜力.③不同脂质的脂肪酸组成差异显著,胆固醇酯和甘油三酯中饱和脂肪酸和单不饱和脂肪酸含量均显著高于游离脂肪酸和磷脂(P＜0.05);而游离脂肪酸和磷脂富含多不饱和脂肪酸,两者含量分别为48.50％和49.96％,远高于胆固醇酯和甘油三酯的13.11％和24.36％,具有显著差异(P＜0.05).     

大米蛋白水平对成熟期大鼠体质量及体脂水平的影响

选用蛋白水平(CP)为7%及14%的大米蛋白(R-7,R-14)及酪蛋白(C-7,C-14)喂养20周龄雄性Wistar大鼠2周后,进行大鼠体质量变化、腹腔贮脂水平、血浆总胆固醇、血浆高密度胆固醇、血浆甘油三酯及肝脏胆固醇、甘油三酯含量的测定。与C-7组相比,R-7组大鼠体质量、生长效率、贮藏脂肪含量、血脂及肝脂水平无显著差异。在高蛋白水平(14%)下,R-14组大鼠体质量总增加量、腹腔贮脂水平均低于C-14组,但各组间无显著差异;对比C-14,R-14显著降低了成熟期大鼠血浆总胆固醇、血浆非高密度胆固醇、血浆甘油三酯水平及动脉硬化指数,并且显著降低了肝脏胆固醇及甘油三酯含量。结果表明,蛋白水平是大米蛋白调控体质量及体脂水平主要影响因素之一。随着蛋白水平的增加(7%~14%),大米蛋白能够降低体质量增加量及腹腔贮脂水平,并显著降低成熟期大鼠血浆及肝脏脂质含量,提示大米蛋白潜在的抗肥胖功能与其蛋白水平密切相关。     

Effects of dietary vegetable oils and varying dietary EPA and DHA levels on intestinal lipid accumulations in Atlantic salmon

High dietary content of vegetable oil (VO) has been associated with increased intestinal lipid accumulations in fish. The extent of this in aquacultured Atlantic salmon (Salmo salar L.) and its health effects are not certain. Samples were therefore collected from two separate feeding trials to investigate the effect of high dietary VO on intestinal lipid accumulations in Atlantic salmon. In the first trial, the fish were fed diets high in plant protein and with fish oil or ~80% of the fish oil replaced with either olive oil, rapeseed oil or soybean oil in a land‐based experimental set‐up. The second trial was performed in sea cages under commercial production conditions, and the fish were fed two dietary concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (9.7% or 5.5% EPA + DHA of total fatty acids). Neither dietary VO nor variations in EPA and DHA led to any significant effects on intestinal health or lipid accumulations. There were, however, indications of a delayed lipid transport in the rapeseed oil‐fed fish of the first trial, possibly caused by high dietary ≥18‐carbon fatty acids and low dietary 16:0 fatty acid and cholesterol.     

The Effects of Season and Site of Catch on Morphometric Characteristics,Mineral Content,and Fatty Acids of Sardines (Sardina pilchardus) Caught on the Algerian Coast

The variation of morphometrics, mineral content, and fatty acid composition of sardines was determined in relation to season and site of catch in the Mediterranean Sea. Sardines were caught in two regions of the Algerian coast: Mostaganem and Béni-Saf. In both sites, the contents of phosphorus (223 and 211 mg 100 g^?1) and sodium (95 and 10 mg 100 g^?1) were higher in June than in February. Total lipid content was related to the season, being low in winter (2.9%) and high in summer (11.3%). The fatty acid composition shows a high content of polyunsaturated fatty acids (PUFA) dominated by n-3 fatty acids eicosapentaenoic acid (EPA C20:5 n-3; 10%) and docosahexaenoic acid (DHA C22:6n-3; 25%). However, the content of n-6 fatty acids was relatively low both in winter (3.4%) and summer (4.7%). The saturated fatty acid (SFA) content was appreciable in sardines, which range from 34% to 37% according to season. This is in agreement with the literature related to the Mediterranean sardine.     

The Effect of Prior Frozen Storage (−20°C) on the Quality of Oven-Baked Sardines (Sardina pilchardus)

ABSTRACT

The effect of frozen storage for 3, 30, 60, 90, and 120 days on the quality of sardines baked for 15, 30, and 45 min was studied. The combination of frozen storage with the baking time in linear reduction of yield and moisture led to less juicy products, as well as significant changes in proteins and lipids. A linear increase of C16:0 followed by a linear reduction of C22:6ω-3 was detected due to frozen storage, indicating lipid oxidation. This was also confirmed by the C22:6ω-3/C16:0 and C20:5ω-3/ C16:0 ratios, which were reduced by 36.8 and 32.7%, respectively. The fatty acid profiles of sardine samples were not significantly altered due to oven-baking. A gradual reduction of eicosapentaenoic acid + docosahexaenoic acid (EPA + DHA) of the baked products was observed mainly due to frozen storage. Cholesterol and squalene content increased with increasing the time of baking. A gradual decrease of cholesterol and squalene was observed due to frozen storage.     

Lipid Hydrolysis and Oxidation of Mackerel (Scomber scombrus) Mince

Atlantic mackerel was stored at refrigeration or frozen temperatures under vacuum or in air with various treatments to determine lipid hydrolysis and oxidation in the fish muscle. Lipid oxidation in the fish minces occurred continually as long as the samples were exposed to air independent of hydrolytic activity which was deactivated or retarded by cooking the sample or by lowering the storage temperature (-40°C). Lipid oxidation was observed not only in the free fatty acids, but also in the triacylglycerides and the phospholipids extracted from mackerel mince.