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351.
Effects of dietary substitution of fishmeal with the combined dry microalgae,Nannochloropsis oceanica (NO) biomass residue and casein on growth and body composition of juvenile abalone (Haliotis discus) 下载免费PDF全文
Sung Hyo Myung Won‐Gwan Jung Hee Sung Kim Ye Eun Kim Sung Hwoan Cho Min Seok Jwa Pil Youn Kim Mun Kwan Kim Min‐Woo Park Byeng‐Hak Kim 《Aquaculture Research》2016,47(1):341-348
The effects of dietary substitution of fishmeal with the combined dry Nannochloropsis oceanica (NO) biomass residue and casein on growth performance and carcass composition of juvenile abalone was determined. One thousand two hundred and sixty juvenile abalone were randomly distributed into the 18 L plastic rectangular containers. Five experimental diets in triplicate were prepared. The 28% fishmeal was included into the control (Con) diet. The 25%, 50%, 75% and 100% fishmeal were substituted with the combination of graded levels of dry NO biomass residue and casein, referred to as the NO25, NO50, NO75 and NO100 diets respectively. Finally, the salted sea tangle (ST), Laminaria japonica was prepared to compare the effect of the experimental diets on performance of abalone. The essential amino acids, such as isoleucine, leucine, phenylalanine, threonine and valine tended to increase with dietary substitution of fishmeal with NO biomass residue in the experimental diets. Arginine tended to decrease with dietary substitution of fishmeal with NO biomass residue. Survival of abalone fed the experimental diets was higher than that of abalone fed the ST diet for 16 weeks. Weight gain and specific growth rate (SGR) of abalone fed the NO100 diet were higher than those of abalone fed the all other diets. Weight gain and SGR of abalone linearly increased with dietary substation of fishmeal with NO. Shell length of abalone tended to increase with dietary substitution of fishmeal with the combined dry NO biomass residue and casein. The chemical composition of the soft body of abalone was different among treatments except for moisture content. In conclusion, fishmeal in the diets for abalone could be completely replaced with the combined dry NO biomass residue and casein when the 28% fishmeal was included. 相似文献
352.
采用皱纹盘鲍与九孔鲍进行杂交,并与两亲本自交进行育苗比较.结果表明:自交组的受精率、孵化率以及存活率显著高于杂交组(P〈0.05);皱纹盘鲍(♀)×九孔鲍(♂)和皱纹盘鲍(♂)×九孔鲍(♀)杂交的受精率分别为0.9%和3.2%,受精率存在显著差异(P〈0.05),而孵化率分别为12.4%和13.1%,二者差异不显著(P〉0.05),二者之间幼体存活率的差异也不显著(P〉0.05);自交组和杂交组之间的鲍生长速度存在明显的差异(P〈0.05),杂交组合的生长速度明显比自交组合的要快;但杂交组中稚鲍的存活率和自交组之间差异不显著(P〉0.05). 相似文献
353.
皱纹盘鲍维生素D营养需要的研究 总被引:8,自引:0,他引:8
在以酪蛋白和明胶为蛋白源的精制饲料中添加不同浓度梯度的维生素D,并以海带为对照组饲喂皱纹盘鲍幼鲍103d。结果表明:幼鲍的生长及软体部水分,脂肪和蛋白质含量受到饲料中维生素D添加水平的影响显著,但成活率不受饲料中添加水平的影响;饲料中适量添加维生素D可以提高幼鲍软体部碱性磷酸酶的活力,但饲料中缺乏或过高水平的维生素D导致幼鲍软体部碱性磷酸酶活力的降低;贝壳中灰分及钙、磷含量受饲料中维生素D添加水平的影响显著。以增重,蛋白质增量和软体部碱性磷酸酶的活力为指标,幼鲍饲料中维生素D的适宜含量为100IU·(100g)-1饲料。 相似文献
354.
355.
在水温15.0~23.0℃、容积50L(45cm×31cm×30cm)的塑料水槽中,分别放养3组共15头单重2.24g的仿刺参和3个单重19.99g的紫贻贝,再分别混养2组共5个单重8.75g的皱纹盘鲍,定期投喂海带。120d的饲养表明,混养组间鲍的特定生长率差异不显著(P>0.05),但显著低于单养组(P<0.05),混养C组鲍的成活率显著低于其他组(P<0.05)。混养组中海参的成活率差异不显著(P>0.05),但生长速度随密度增加而降低(P<0.05)。将海参产量计算在内,3种密度下,鲍的饲料系数分别降低11.84%、4.03%和4.51%;海参的放养密度为3个/箱时,鲍的饲料系数接近单养鲍;紫贻贝生长停滞,成活率随海参密度的增加而降低。 相似文献
356.
提高皱纹盘鲍稚鲍越冬成活率与加速生长的初步研究 总被引:1,自引:0,他引:1
1984年冬与1985年春,对不同大小的稚鲍越冬成活率进行了研究。冬季死亡的威胁主要为个体小与低水温,稚鲍的个体越小,对冬季低水温的忍受力越弱,体长小于8~10mm的稚鲍死亡率极高。使用升温循环净化海水与投喂人工合成饲料是提高小规格稚鲍成活率与加速生长的有效措施。平均体长7.1(4.0~9.5)mm稚鲍,经163天饲养成活率66.0%,平均体长达23.1mm。饲养生物量达16.8kg/m~3。用自制的配合饲料投喂,稚鲍平均日增长114μm,其中最后的60天,日增长为137μm。通过对体长8.0~24.0mm稚鲍测量,得出体重与体长的关系公式为W=0.13L~(3·015)。 相似文献
357.
Thisstudy investigated the effects of shelter surface area (SSA) on the feeding,growth and survival of the donkey-ear abalone, Haliotisasinina reared in mesh cages (0.38×0.38×0.28m) suspended in flow-through tanks (water volume = 6m3). Cages had sections of polyvinylchloride (PVC) thatprovided shelters with surface area of 0.22 m2, 0.44m2 and 0.66 m2.Hatchery-produced abalone with initial shell length of 32 ± 1mm and wet weight of 7.5 g were stocked at 50individuals cage–1 that corresponded to stocking densities ofca. 227, 113 and 75 abalone m–2 of SSA. The ratios of sheltersurface area to cage volume (SSA:CV) were 5.5, 11 and 16.5. Abalones wereprovided an excess red seaweed Gracilariopsis bailinae(= Gracilaria heteroclada) at weekly intervals overa 270-day culture period. Feeding rates (18–20% of wet weight), foodconversion ratio (26–27) and percent survival (88–92%) did notdiffer significantly among treatments (p > 0.05). Body size at harvest rangedfrom 56 to 59 mm SL and 52 to 57 g wet body weightwith significant differences between abalone reared at SSA 0.22m2 and 0.66 m2 (p < 0.05).Abalone reared in cages with 0.66 m2 SSA grewsignificantly faster at average daily growth rates of 132 m and188 mg day–1. Stocking densities of 75–113m–2 SSA in mesh cages suspended in flow-throughtanks resulted in better growth of abalone fed red seaweed. 相似文献
358.
从皱纹盘鲍雌性个体的足部肌肉提取总DNA后,通过聚合酶连式反应(PCR)技术扩增得到一个扩增产物。经克隆、筛选、确定重组子产物。测序得到了长度为511bp的启动子片段。分析测序结果发现,皱纹盘鲍肌动蛋白基因启动子DNA序列与目前己知的红鲍相应序列的相似度为95%;GC碱基含量为38.93%,较红鲍的低(59.2%);所得序列含有高度保守的基本表达调控元件,即一个CAAT框和四个TATA框。 相似文献
359.
Apparent (APD) and true (TPD) protein digestibility and apparent (AAAA) and true (TAAA) amino acid availability of fish meal and plant protein ingredients utilized in the South African animal feed industry (corn gluten meal, soya bean meal, cottonseed meal, sunflower meal, canola meal, peanut meal, lupins and faba beans), incorporated at 450 g kg?1 into single protein diets, were determined with juvenile South African abalone (Haliotis midae). Soya bean meal (96.34%) and lupins (96.51%) presented the highest APD values, with corn gluten meal (76.08%) the lowest value, while values for sunflower meal (92.21%), canola meal (93.94%) and faba beans (93.17%) were above 90%. APD values for cottonseed meal (86.28%) and peanut meal (86.73%) were comparable with that of fish meal (82.94%). A correlation coefficient (r) of 0.99 was found between ADP and mean AAAA. Furthermore, amino acid availabilities were relatively consistent within various feed ingredients. The mean amino acid secretion from a protein‐free diet was 19.08 mg 100 g?1 dry diet, resulting in a mean increase of 1.88% units over all feed ingredients when comparing TAAA with AAAA. Calculated APD according to APD coefficients determined with single protein diets underestimated determined APD in several compound diets by 1.10–6.50%, while mean AAAA was underestimated by 6.93%. 相似文献
360.
This study dealt with the detection of parentage in a mixed family tank of abalone Haliotis discus hannai using microsatellite DNA markers. As a preliminary investigation, the early growth rate between selected and non-selected
abalone families, which were reared together in the mixed family tank from settlement stage to juvenile stage (7 months of
age), was also compared. The selected families were derived from seven parents (three females and four males) selected for
larger size in shell length at about 1-year-old, and the non-selected families originated from five wild captives (three females
and two males). Parentage analysis based on eight microsatellite markers unambiguously allocated the 170 juveniles sampled
from the single tank to the 17 parental pairs. The family size was highly heterogeneous among families, as two males in the
selected families and one male in the non-selected families dominated the contribution to the offspring pool (>80%). The mean
shell length of the selected families was approximately 23% larger than that of the non-selected families (Student’s t-test, P<0.001). This study demonstrated that the use of microsatellite markers is effective for parentage determination in the mixed
family farming, commonly used in abalone hatcheries, and selective operations for larger size could improve the growth of
the next generation. 相似文献