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以含27.0%的鱼粉饲料为对照组,分别用3.0%、6.0%、9.0%、12.0%的玉米蛋白粉替代对照饲料中的鱼粉,另在12.0%的玉米蛋白粉替代的基础上添加了0.1%的羟基蛋氨酸钙,制成6种试验饲料(A、B、C、D、E、F),分别喂养日本沼虾幼虾。养殖实验分两阶段进行。第一阶段喂养初始体重(0.12±0.04)g的幼虾30 d,第二阶段喂养初始体重(0.23±0.12)g的幼虾23 d,测定其生长和肌肉营养组成。结果表明:随着饲料中玉米蛋白粉用量的增加,各组幼虾的相对增长率和相对增重率呈下降趋势,但差异不显著(P>0.05),各组日本沼虾成活率无显著差异(P>0.05)。当饲料中玉米蛋白粉的用量在12.0%以内时,养殖日本沼虾肌肉的水分、脂肪、灰分、总氨基酸、总必需氨基酸含量均与对照组无显著差异,但日本沼虾肌肉的脂肪酸组成随玉米蛋白粉用量的增加而变化,玉米蛋白粉用量超过9.0%时,沼虾肌肉中多不饱和脂肪酸和DHA+EPA含量显著减少。 相似文献
996.
选取300只健康、活泼的28日龄豁眼鹅,公母各半,体重为1 142.68(±50.64)g,随机分为3组,分别是血粉3%组、膨化血粉3%组和鱼粉3%组,每组设5次重复,每次重复20只鹅,试验时间28 d,研究在相同营养水平条件下,等比例的血粉、膨化血粉以及鱼粉对生长鹅生长性能和盲肠微生物菌群的影响和膨化血粉替代鱼粉的可行性。结果表明:平均日增重、饲料转化率以及盲肠内容物中乳酸杆菌、双歧杆菌数量的高低顺序为鱼粉组>膨化血粉组>血粉组,鱼粉组与膨化血粉组之间差异不显著,但均显著高于血粉组(P<0.05)。结果说明膨化血粉的饲喂效果显著好于血粉,在生长鹅日粮中可以3%比例等量替代鱼粉。 相似文献
997.
旱作大豆播种密度对产量和水分利用效率的影响 总被引:1,自引:0,他引:1
为了提高旱作区大豆种植效益,充分利用当地降水资源,在甘肃东部地区开展播种密度对不同成熟期大豆品种产量及水分利用效率的影响研究。结果表明,不同类型大豆品种随播种密度增加,其主要经济性状单株荚数、单株粒数、每荚粒数和单株粒重均呈下降趋势;播种密度对不同类型品种田间耗水量影响不显著;在播种密度9.0万株/hm2~27.0万株/hm2的范围内,晚熟品种‘汾豆78’、‘晋豆23’适宜种植密度为18.0万株/hm2,早熟品种‘中黄30’、‘晋豆19’适宜种植密度为22.5万株/hm2;适宜播种密度能够明显提高旱作区大豆籽粒产量和水分利用效率。 相似文献
998.
Apparent digestibility coefficients of selected protein feed ingredients for loach Misgurnus anguillicaudatus 下载免费PDF全文
Z.J. Chu D.H. Yu Y.C. Yuan Y. Qiao W.J. Cai H. Shu Y.C. Lin 《Aquaculture Nutrition》2015,21(4):425-432
Apparent digestibility coefficients of dry matter, crude protein, lipid and energy, and amino acids availability in white fish meal, brown fish meal, meat meal, fermented soybean meal, soybean meal and rapeseed meal were determined for loach (Misgurnus anguillicaudatus) (12.05 ± 0.21 g), using a reference diet with 5 g kg?1 chromic oxide and test diets that contained 700 g kg?1 reference diet, by weight, and 300 g kg?1 of the test feed ingredients. The juvenile loach was held in 300‐l tanks at a density of 30 fish per tank. White fish meal, brown fish meal, meat meal and fermented soybean meal had highest apparent digestibility coefficients (ADCs) of dry matter, crude protein and gross energy among ingredients tested, ranged from 50.4% to 60.9% for dry matter, from 64.6% to 88.4% for crude protein and from 57.9% to 79.0% for gross energy. The apparent digestibility coefficients of dry matter ranged from 61.0% to 66.9% for animal products and 50.4% to 60.7% for plant products. For crude protein, apparent digestibility coefficients of protein exceeding 80% were observed for white fish meal, brown fish meal, meat meal and fermented soybean meal, and the apparent digestibility coefficients of protein in rapeseed meal were the lowest among all the treatments. Lipids from both animal and plant feedstuffs were poorly digested by loach, ranging from 64.0% to 77.6%. The apparent digestibility coefficients of energy were similar to those of dry matter and protein, and the highest and lowest ADCs of energy were found in WFM and RM, respectively. The loach used dietary phosphorus from the animal feedstuffs more efficiently than from plant feedstuffs (soybean meal and rapeseed meal), with ADC‐values ranging from 42.3% to 53.1% and from 25.1% to 32.7%, respectively. For the animal products, the availabilities of amino acids in white fish meal and brown fish meal were higher than that in meat meal, expect for Met, Asp, Pro, Gly, and Cys. Among all the plant products, the availabilities of amino acids in fermented soybean meal were higher than in soybean meal and rapeseed meal, and thus had a greater potential to be used as a dietary replacement of fish meal in loach diets. 相似文献
999.
Effect of krill phospholipids versus soybean lecithin in microdiets for gilthead seabream (Sparus aurata) larvae on molecular markers of antioxidative metabolism and bone development 下载免费PDF全文
R. Saleh M.B. Betancor J. Roo V. Benítez‐Dorta M.J. Zamorano J.G. Bell M. Izquierdo 《Aquaculture Nutrition》2015,21(4):474-488
The objective of the present study was to compare the effectiveness of dietary marine phospholipids (MPL) obtained from krill and soybean lecithin (SBL) on the rearing performance and development of seabream (Sparus aurata) larvae. Larvae were fed from 16 to 44 day posthatching (dph) five formulated microdiets with three different levels (50, 70 and 90 g kg–1) of phospholipids (PL) obtained either from an MPL or from a SBL source. Larvae‐fed MPL show a higher survival, stress resistance and growth than those‐fed SBL, regardless the dietary PL level. Overall, the increase in MPL up to 70 g kg–1 total PL in diet was enough to improve larval gilthead seabream performance, whereas even the highest SBL inclusion level (90 g kg–1 PL) was not able to provide a similar success in larval growth or survival. Inclusion of SBL markedly increased the peroxidation risk as denoted by the higher TBARs in larvae, as well as a higher expression of CAT, GPX and SOD genes. Moreover, SBL tends to produce larvae with a lower number of mineralized vertebrae and a lower expression of osteocalcin, osteopontin and BMP4 genes. Finally, increasing dietary MPL or SBL lead to a better assimilation of polyunsaturated fatty acids in the larvae, n‐3HUFA (especially 20:5n‐3) or n‐6 fatty acids (especially 18:2n‐6), respectively. In conclusion, MPL had a higher effectiveness in promoting survival, growth and skeletal mineralization of gilthead seabream larvae in comparison with SBL. 相似文献
1000.
Effect of dietary glutathione supplementation on the biological value of rapeseed meal to juvenile grass carp,Ctenopharyngodon idellus 下载免费PDF全文
X. Yuan Y. Zhou X.‐F. Liang X. Guo L. Fang J. Li L. Liu B. Li 《Aquaculture Nutrition》2015,21(1):73-84
An 8‐week feeding trial was conducted to investigate the effects of dietary rapeseed meal (RM) and glutathione supplementation (400 mg kg?1) on growth and intestinal microbiota of grass carp (Ctenopharyngodon idellus). Dietary 450 g kg?1 RM decreased growth and feed intake, while increased the activities of serum alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine transaminase (ALT). The hepatic damages were also observed the significant lower condition factor (CF), hepatosomatic index (HSI) and the symbol of parenchymal damage. Glutathione supplementation increased weight gain and feed intake while significantly decreased the three serum biochemistry parameters compared with the RM group. In addition, HSI, CF and pathology reports revealed that glutathione supplementation alleviated the damage caused by RM on the fish liver. In addition, glutathione had a positive effect on the intestinal digestive capacity. PCR‐denaturing gradient gel electrophoresis (DGGE) analysis indicated a higher similarity between dietary glutathione supplementation and control group. In conclusion, we demonstrated dietary 450 g kg?1 rapeseed meal lead to negative health outcomes, while glutathione supplementation neutralize the adverse effect of rapeseed meal presented in aqua feed through alleviating the damage factors on the fish liver. 相似文献