The objectives were to develop and evaluate: 1) growthrate models, 2) body lipid, moisture, and energy models for white sturgeon fed at various feeding rates(FR; % body weight [BW] per day) and then evaluate response...
详细信息
The objectives were to develop and evaluate: 1) growth rate models, 2) body lipid, moisture, and energy models for white sturgeon fed at various feeding rates(FR; % body weight [BW] per day) and then evaluate responses at proportions of optimum feeding rate(OFR) across increasing BW(g). For objective1,19 datasets from the literature containing initial BW, FR and specific growth rate(SGR; % BW increase per day) were used. For objective 2.12 datasets from the literature(11 from objective 1) containing SGR,FR,final BW,body lipid(%),protein(%),ash(%),moisture(%),and energy(kJ/g) were used. The average rearing temperatures was 19.2 ± 1.5 ℃(mean ± SD). The average nutrient compositions and gross energy of the diets were 45.7 ± 4.3% protein,14.8 ± 3.2% lipid, and 20.4 ± 1.3 kJ/g,respectively. The logistic model was used for objectives 1 and 2 to develop a statistical relationship between SGR and FR, then an iterative technique was used to estimate OFR for each dataset. For objective 2, the statistical relationship between body lipid, energy, and moisture and FR was established. Using the OFR estimate, SGR, body lipid, energy and moisture were computed at various FR as a proportion of OFR, Finally, a nonparametric fitting procedure was used to establish relationships between SGR, body lipid, energy and moisture(responses)compared with BW(predictor) at various proportions of OFR. This allows visualization of the effect of under-or over-feeding on the various responses. When examining the differences between OFR at 100%and various proportions of OFR, SGR differences decrease and moisture differences increase as BW increases. Lipid and energy differences decrease as BW increases. To our knowledge, these are the first description of changes in nutrient compositions when white sturgeon are fed at various FR. Because physiological and behavioral properties that are unique to sturgeon, results from this study are specific to sturgeon under the conditions of this study and cannot b
One of the goals of the aquaculture industry is to understand and control growth associated traits through selective *** the present study the molecular basis of growth heterogeneity in the European sea bass(Dicentrar...
详细信息
One of the goals of the aquaculture industry is to understand and control growth associated traits through selective *** the present study the molecular basis of growth heterogeneity in the European sea bass(Dicentrarchus labrax)was *** establish growth heterogeneity in a group of hatchery bred sea bass individuals were tagged and their specific growth rates(SGR)determined at monthly *** expression in the brain,liver and white muscle from fish with the most divergent sustained SGR(6 individuals of the first and last quartile)was assessed using SuperSAGE(Serial Analysis Gene Expression)combined with next generation SOLiD4 sequencing.A total of approx.11 million edited tags(26 bp),on average 2 million tags per SAGE library,that represented 47.071 unique transcripts were *** of transcripts in fish with high and low SGR yielded 344,698 and 601 differently expressed tags(0.01%false discovery rate and 4-fold change)in brain,liver and muscle,*** tags were mapped onto the sea bass genome and approximately one third of the tags could be assigned to annotated *** enrichment analysis revealed in liver,muscle and brain intricate gene expression changes in endocrine regulatory pathways involved in growth,metabolic and the stress axis,underlying divergent SGR in sea bass.
Excessive accumulation of dissolved organic matter (DOM) in the culture ponds of Spirulina platensis is usually considered to be one of the potential factors affecting the production of S. platensis, however, we are n...
详细信息
Excessive accumulation of dissolved organic matter (DOM) in the culture ponds of Spirulina platensis is usually considered to be one of the potential factors affecting the production of S. platensis, however, we are not quite aware of effects of DOM on the growth and pigments synthesis of S. platensis. In the present study, S. platensis was grown in batch or semi-continuous cultures using the filtrate in the culture ponds that had not been renewed for years. It was found that disssolved organic carbon up to 60 mg/L did not bring about an inhibitory effect on the growth of S. platensis, but increased the contents of chlorophyll a and phycocyanin instead. However, further accumulation of dissolved organic matter could decrease the content of chlorophyll a .
This study was carried out to study the effect of adding different levels of date palm seed (Phoentix dactyliJProus) powder in the diet of common carp (Cyprinus carpio) at fish laboratory of Animal Production Depa...
详细信息
This study was carried out to study the effect of adding different levels of date palm seed (Phoentix dactyliJProus) powder in the diet of common carp (Cyprinus carpio) at fish laboratory of Animal Production Department, College of Agricultural Sciences, Sulaimani University, Sulaimani, Iraq. The actual experimental feeding trials were conducted for 70 d and the adaptation period for 21 d. A total of 81 common carp fingerlings weighted 62 ± 2 g were divided into three experimental groups. The control treatment T1 was with 0 g date palm seed, T2 with 2.5 g date palm seed per kg diet and T3 with 5 g date palm seed per kg diet. Each treatment was in three replicates in which three common carp fingerlings were stocked in each aquarium which fed the experimental diets twice daily. The results indicated that weight gain (WG) and specific growth rate (SGR) in the third treatment (T3) group were significantly higher than those of fish fed control diets. T2 consumed more diet than other treatments with 306.940 g with higher feed conversion ratio (FCR); T3 was higher significantly in food efficiency. No significant (P 〈 0.05) differences obtained from consumed protein while the protein efficiency ratio was significantly higher in T3 with 319.323. Control was higher significantly in flesh weight without viscera with the third treatment; in flesh weight without head and viscera each the control and the second treatment was significantly higher than the third treatment. As a conclusion, the date palm seeds powder have a positive effect on growth performance of common carp.
The effect of salinity on the growth and muscle nutritional quality of theExopalaemon carinicauda was studied through testing the survival rate, specificgrowthrate, muscle nutrient composition, amino acid composition...
详细信息
The effect of salinity on the growth and muscle nutritional quality of theExopalaemon carinicauda was studied through testing the survival rate, specific growthrate, muscle nutrient composition, amino acid composition and content by the culturingin different salinities(0-30).The results showed that the survival rate of salinity (0-30)had no significant difference (P>0.05), and the specific growth rates at salinity 15 andsalinity 20 were significantly higher than others(P>0.05); the muscle moisture contentand the crude fat content significantly decreased(P0.05). No significant difference was found in total amino acid contentor total essential amino acid content from salinity 0 to 30(P>0.05). Total delicious aminoacid content at salinity 15-30 was significantly higher than those at salinity 0-10(P0.05). Theresults suggest that the suitable salinity for muscle nutritive value ranges from 15 to 30,and the Exopalaemon carinicauda can potentially be cultured above the salinity 15.
Objective] The aim was to explore the potential of Nitzschia capitel ata as excel ent baits and bioenergy, and the optimal light intensity and nitrogen-to-phos-phorus (N/P) ratio suitable for its growth were researc...
详细信息
Objective] The aim was to explore the potential of Nitzschia capitel ata as excel ent baits and bioenergy, and the optimal light intensity and nitrogen-to-phos-phorus (N/P) ratio suitable for its growth were researched as wel . [Method] With light intensity gradient set, Nitzschia capitel ata was cultured with the same nutrients at (25 ±1) ℃ and light cycle at 12 h/d to select optimal light intensity. Then, Nitzschia capitel ata was cultured with the same condition, and nitrogen-to-phospho-rus ratios at 5∶1, 6∶1, 7∶1 and 8∶1. [Result] With light intensity at 3 000 lx, specific growth rate and standing stock achieved the highest at 0.51 d-1 and 7.97×104 cel s/ml. The growth condition with nitrogen-to-phosphorus ratio at 6∶1 was the most suitable for Nitzschia capitel ata growth. [Conclusion] The optimal light intensity and nitrogen-to-phosphorus ratio were 3 000 lx and 6∶1, respectively, for Nitzschia capitel ata.
暂无评论