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1.
人工驯养野生动物是获取野生动物产品的重要手段,但是非法盗猎的野生动物产品以人工饲养的名义进入市场,就会对野生动物的保护形成挑战。因此,准确鉴别市场上的动物产品是来自养殖场还是野外,是保护野外种群,维持养殖业正常秩序的关键。本研究以北美水貂(Neovison vison)为例,基于颧骨内侧空间(ZAS)、颧宽(ZAA和ZBA)、颅基长(BSL)、下颌长(MDL)、眶后收缩(POC)和最大面部宽度(GFB)等量度,建立了9个头骨形态计量学指标:POC/GFB、POC/BSL、POC/MDL、ZAS SQRT/BSL、ZA SSQRT/MDL、ZBA×BSL/2ZAS、ZBA×MDL/2ZAS、ZBB×BSL/2ZAS和ZBB×MDL/2ZAS。野生组(n=32,9雄23雌)和饲养组(n=45,35雄10雌)的比较表明,除POC/GFB外,所有指标对于在两组样品之间均有显著差异,整体判别正确率为73.2%—85.5%。在性别已知的情况下,雄性的整体正确率为82.4%—93.8%,雌性为41.7%—85.7%。为此,应针对不同性别、不同来源的动物建立相应的参考数据,利用似然比进行鉴别。本研究的结果不仅可用于北美水貂的鉴别,也为其他小型食肉动物的鉴别提供经验。  相似文献   
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This study was conducted to examine the potential for implantation and sustainable fetal development of mouse embryos cultured from the pronuclear to blastocyst stage. Pronuclear embryos from ICR mice (Harlan Sprague‐Dawley) were cultured in Sydney IVF sequential media (Cook) to the blastocyst stage in medium only or co‐cultured with autologous cumulus cells. We also experimented with co‐culture in 100 µL drops. Drop co‐culture produced blastocyst formation rates with a mean of 47.0%, which was significantly higher (P < 0.05) compared to embryos cultured in identical culture conditions except without cumulus cells at 27.3%. Blastocysts obtained in vitro in Cook medium only and co‐cultured in Cook medium with cumulus cells were transferred to pseudopregnant females of ICR strain. The day of blastocyst transfer into surrogate females was designated as post‐transfer of blastocyst day 1 (PT 1). The implantation and fetal development was compared to embryo transfer of in vivo derived blastocysts, which served as controls. There were no statistical differences for implantation and fetal development rates for blastocysts cultured in vitro in either Cook medium only or co‐culture in Cook medium with cumulus cells compared to in vivo‐derived blastocysts. The advantage of the co‐culture system is in generating more blastocysts available for transfer.  相似文献   
3.
Trails with glyphosate spred onto the soil around profusely suckering apple cherry pear and plum trees so as to wet the suckers, were carried out at ballygagn. Are East malling Kent; Long ash tom, Bristol and Loughall N Ireland Trees were sprayed to simulate normal weed killing in winter when the suckers were dormant, in April when the sucker buds had recently burst and in june when the sucker were in full leaf no damage was cused to the parent trees in the year of treatment or the following year in any of the trails. No glyphosate residues (< 1ppm) were found in the leavws of the parent apple tree at all soles sucker deths or damage was greater and apple trees. At all sites sucker death or damage was greatest and re grow the least with the full leaf spray. Damage was greater with the April than the January cpray Sucketrs of the different kinds of from varied in susceptibility ot glyphosate There was no damage ot the parent trees at long Ashton when suckers were sparyed to run off in July  相似文献   
4.
Abstract. Ovarian samples were collected from plaice, Pleuronectes platessa , captured in the highly oiled Aber Wrac'h and Aber Benoit estuaries at four intervals during 1979–1980, following the Amoco Cadiz crude oil spill. Reference plaice were obtained along the western and southern coasts of Brittany. Tissue samples were fixed, processed and stained by routine histologic procedures. Ovaries were examined for histopathologic changes and for four different types of follicles. The concentrations and percentages of four types of ovarian follicles (primordial, primary, growing and mature) were determined for plaice ovaries within each sampling site at each sampling interval. Reference site ovaries, which were considered representative of the ovarian cyclic events for plaice along the Brittany coast, had primordial and primary follicles in high concentration in the summer season and in low concentration in the winter season. Concentrations of mature ovarian follicles in reference site plaice ovaries were low in the summer and high in the winter seasons. Growing follicles were observed infrequently in the reference site plaice ovaries. The seasonal pattern exhibited by follicles in ovaries from Aber Benoit plaice was similar to that observed in the reference site ovaries, but both the concentrations and percentages of follicle types were lower. The seasonal pattern of follicle types in Aber Wrac'h plaice ovaries was the reverse of that seen in the reference site plaice ovaries. In the Aber Wrac'h samples, concentrations of primordial and primary follicles were high in the winter months and low in the summer season, and no mature follicles were observed at any season. Growing follicles were seen more frequently in Aber Wrac'h and Aber Benoit plaice ovaries than in reference site plaice ovaries at all sampling intervals. Other than atretic follicles with an associated leucocytosis, no histopathologic conditions were observed in any ovary.  相似文献   
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A healthy population of captive Amur tigers might assist recovery of the wild population in Northeast China if individuals were properly prepared and considered suitable for release in the wild. We analyzed the breeding records of 68 female Amur tigers from 1995 to 2010 in the Hengdaohezi Felid Breeding Center of China and compared the reproductive parameters of this population to wild female Amur tigers. We found that the reproductive parameters of the captive population (the age of first parturition, length of gestation and litter survival rate) were not significantly different from those of wild Amur tigers. Differences in birth date and litter size between wild and captive populations may be caused by management protocols for the captive population or insufficient field data from the wild population. Reproductive parameters of females giving birth after losing a litter were similar to parameters of females that did not lose a litter, except for birth date. These results provide no indication of major problems in using captive females for a breeding program for release of cubs into the wild, but additional information is still needed to assess their suitability.  相似文献   
7.
Adrian E  STOTT  Toshio  TAKEUCHI  Yasuyuki  KOIKE 《Fisheries Science》2004,70(6):1070-1081
ABSTRACT:   A new abalone postlarval culture system, Stott's abalone postlarval production system (SAPPS), is being developed as an alternative method for settling larvae and on-growing postlarval abalone. SAPPS was tested in trial 1 using two commercially available artificial diets, Adam and Amos (Adam; supplied by Adam and Amos, Mt Barker, SA, Australia) and Cosmo (Cos; supplied by Cosmo, Matsuyama, Japan), against the diatom biofilm method (Diatom). In trial 2, SAPPS was tested against the previous production system (PPS, used by Stott et al. 2002). Larvae were induced to metamorphose and the resulting postlarvae were on-grown in 10-L flow-through tanks for 28 days in their respective treatments. The final survival of postlarvae was significantly higher ( P  < 0.05) in the SAPPS-Cos group (56.7 ± 11.15%) than in the Diatom (9.4 ± 2.7%) and SAPPS-Adam groups (8.5 ± 1.1%). The final length of postlarvae in SAPPS-Cos (1065 ± 73 µm) was significantly higher ( P  < 0.05) than those in the other two treatments (average of 841–883 µm). In trial 2 the metamorphosis rate was improved by using Spirulina platensis. The final length of postlarvae in SAPPS (1449–1471 µm) was significantly higher ( P  < 0.05) than PPS (1065–1075 µm) and Diatom (993 µm). There is potential for SAPPS to be used as an alternative to the current diatom method in the culture of postlarval abalone.  相似文献   
8.
ADRIAN  STOTT  TOSHIO  TAKEUCHI  YASUYUKI  KOIKE  HIROSHI  YAMAKAWA  OSAMU  IMADA 《Fisheries Science》2002,68(5):1088-1093
Feeding artificial micro diets instead of diatoms may allow a more constant and controlled form of nutrition, and thus results in lower mortality rate and increased growth. A 4-week trial was conducted to determine the growth and survival of postlarval Haliotis discus discus (Reeve.) postlarvae fed three experimental micro particle diets, and naturally occurring diatoms. A completely randomized design was adopted with each diet being replicated three times. All diets varied in terms of particle size and gross composition. Survival rate was significantly lower ( P  < 0.05) in the diatom diet (19.5 ± 2.1%) when compared with the K-1 diet (38.8 ± 8.9%), the K-2 diet (43.7 ± 5.6%) and the MD-Q diet (44.2 ± 14.8%). The size of postlarvae fed the four diets was not significantly different ( P  > 0.05). There was also little difference in the daily growth rate. Based on the results of this work for the preliminary implementation of artificial food as a replacement diet for diatoms, it seems that postlarval H . discus discus readily consumes artificial micro particle diets and has a superior survival rate when compared to that of diatoms.  相似文献   
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