Diversity,endemism and conservation of the freshwater crabs of China (Brachyura: Potamidae and Gecarcinucidae)     

Neil CUMBERLIDGE  Peter K. L. NG  Darren C. J. YEO  Tohru NARUSE  Kirstin S. MEYER  Lara J. ESSER 《Integrative zoology》2011,6(1):45-55

China lies at the heart of the global center of freshwater crab diversity in tropical Asia, where the 2 most diverse families occur: Potamidae (505 species, 95 genera) and Gecarcinucidae (344 species, 59 genera). China stands out as the country with the highest species richness of freshwater crabs globally. Its fauna comprises 243 species in 37 genera and in 2 families, and species discovery is still progressing at a rapid pace. The vast majority of the species are distributed in southwest, south central and eastern China in the Oriental zoogeographical region. China also stands out as having a highly endemic freshwater crab fauna at the species level (96%) and at the genus level (78%). Although the recent International Union for the Conservation of Nature (IUCN) red list conservation assessment found only 6 out of 228 species (2%) to be threatened (5 potamids and 1 gecarcinucid), the majority (more than 75%) of Chinese species are regarded as data deficient, so the number of threatened species is likely to be a serious underestimate. Threats from increasing habitat destruction and pollution are a major concern due to the rapidly growing economy and massive developments taking place in China. There is therefore an urgent need for increased species exploration and for the development of a conservation strategy for China's threatened (and potentially threatened) endemic freshwater crab species.  相似文献   

日粮核苷酸对早期断奶小鼠肝脏基因表达的影响     

王兰芳  乐国伟  虞泽鹏  施用晖 《上海交通大学学报(农业科学版)》2006,24(4):341-344,348

研究了日粮核苷酸对早期断奶小鼠肝脏基因表达的影响:选取16～17日龄健康BALB/C雄性小鼠60只,分成对照组和实验组,分别饲喂添加0、0.25%核苷酸的无核苷酸基础日粮,在实验的第2、4、10天采用差异显示技术分离小鼠肝脏中差异表达的基因。结果表明:采用6对引物分离到4条差异表达的基因片断。采用差异显示技术初步分离到4个受核苷酸影响差异表达的基因,这些片段需要做进一步的验证。  相似文献   

受冷害和未受冷害黄瓜中氨基酸含量的变化     

冯双庆  Y.T.Yao  J.Buchaman-smith&E.C.Lougheed 《中国农业大学学报》1994,(3):251-256

本文研究了贮藏在0℃下黄瓜的冷害与时间的关系,测定了0℃和20℃下黄瓜中氨基酸种类、含量及其贮藏中的变化,结果表明,上述2种温度对谷氨酸、丙氨酸及总氨基酸含量的影响最大,0℃下受冷害黄瓜中丙氨酸含量及丙氨酸占总游离氨基酸的百分比要比在20℃下贮藏的高,而谷氨酸含量及其占总氨基酸含量的百分比却比20℃下的要低。  相似文献   

Estimating the ideal dietary indispensable amino acid pattern for growth of white sturgeon, Acipenser transmontanus (Richardson)   总被引：2，自引：0，他引：2  

W. K. NG  S. S.O. HUNG 《Aquaculture Nutrition》1995,1(2):85-94

Juvenile white sturgeon (Acipenser transmontanus, Richardson) were fed or starved for 4 weeks, and their whole body amino acid composition determined at the beginning and the end of the study. The amino acid compositions of muscle, liver, gill and gastrointestinal tract, and the free amino acids in plasma of fed and starved fish were also determined. Very little variation was observed in the amino acid compositions of all the tissues examined after starvation. However, the plasma free amino acids were significantly (P < 0.05) decreased following starvation. On the basis of the amino acid composition and nitrogen retention values of the whole fish, daily indispensable amino acid requirements for protein accretion and obligatory nitrogen losses (mg amino acid 100 g body weighr^?1 day^?1) were estimated. The pattern of indispensable amino acids required for each of these is different, with the pattern for protein accretion containing much higher levels of lysine, but lower levels of tryptophan and sulfur amino acids. Individual amino acid retention rates varied from 33.3% of dietary tryptophan to 80.2% for arginine. The estimated dietary indispensable amino acid pattern for young growing white sturgeon (expressed as a percentage of total indispensable amino acids plus cystine and tyrosine) is: arginine, 14.0; histidine, 6.6; isoleucine, 8.8; leucine, 12.5; lysine, 15.8; methionine (plus cystine), 6.6; phenylalanine (plus tyrosine), 15.5; threonine, 9.7; tryptophan, 0.8; and valine, 9.7.  相似文献   

乐山市中心城区越冬水鸟群落结构的变迁     

杨培培  思超  周博 《安徽农业科学》2016,44(24)

[目的]研究近年来乐山市中心城区越冬水鸟群落结构的变迁。[方法]于2008年1月和2014年1月分别对乐山市中心城区越冬水鸟群落结构进行了调查。[结果]伴随城市化的快速发展,乐山市中心城区“三江”水鸟的群落结构发生了明显变化,以红嘴鸥(Larus ridibundus)和崖沙燕(Riparia riparia)等为代表的中小型鸟类逐步取代大中型的鸭科(Anatidae)鸟类成为群落优势种。[结论]该研究可为评估经济活动和生态环境对乐山市中心城区水鸟群落的影响奠定基础。  相似文献   

Clinical and haematological features of haemangiosarcoma in dogs   总被引：1，自引：0，他引：1  

C. Y. NG  J. N. MILLS 《Australian veterinary journal》1985,62(1):1-4

Canine haemangiosarcoma was studied retrospectively in 31 cases recorded among 2,871 dogs presented for necropsy (1.08%). The German Shepherd breed was more frequently represented than other breeds. Affected dogs were older than 5 years (mean 9.1 years). Nineteen were males. Presenting signs often included episodic lethargy and weakness, with depression, anorexia and mucosal pallor. Spleen and lungs were the most frequently affected sites. Haematological findings in 9 dogs with splenic or hepatic haemangiosarcoma included a mild to moderate normochromic anaemia, neutrophilia, thrombocytopaenia, poikilocytosis and increased target cells. Acanthocytes occurred in 90% of cases, schizocytes in 80% and keratocytes and metarubyricytes in 70%. Fibrin split products were increased in 2 of the 3 cases in which they were measured. The changes in erythrocyte morphology are considered to be useful diagnostic features of canine haemangiosarcoma.  相似文献   

The effect of time between doses on serological response to a recombinant multivalent pilus vaccine against footrot in sheep     

CL SCHWARTZKOFF  PR LEHRBACH  ML NG  A. POI 《Australian veterinary journal》1993,70(4):127-129

SUMMARY The response of sheep to a recombinant multivalent footrot vaccine containing pilus antigens was examined after the administration of two doses of vaccine at Intervals ranging from 2 to 52 weeks. Agglutinating antibody titres were measured 3 weeks after the second vaccination and showed that lengthening of the interdose interval results in higher agglutinin titres. The capability of sheep to mount an increasingly strong immune response as the interval between doses is increased provides an opportunity to maximise the usefulness of vaccination by administering the first dose well before an expected footrot transmission period. This advantage of increasing the interdose interval has not been reported for traditional, whole-cell footrot vaccines, and use of the new pilus vaccine in this manner may improve prospects for disease control. Furthermore, sheep given a third dose either 6 or 12 months after their initial two-dose vaccination program achieved significantly higher titres than those elicited after the second dose, suggesting the likelihood of further improvement in disease control in successive seasons.  相似文献   

Investigation of outbreaks of a novel disease, 'Sleepy Grouper Disease', affecting the brown-spotted grouper, Epinephelus tauvina Forskal   总被引：2，自引：0，他引：2  

F. H. C. CHUA  M. L. NG  K. L. NG  J. J. LOO  J. Y. WEE 《Journal of fish diseases》1994,17(4):417-427

Abstract. A novel disease affecting the brown-spotted grouper, Epinephelus tauvina Forskal, described here as Sleepy Grouper Disease¹ (SGD), resulted in significant economic losses in some Singaporean marine net-cage farms from April to August 1992. Investigations suggested that the aetiological agent was a virus, probably introduced with imported groupers. The virus was provisionally identified as an iridovirus on morphological evidence. The disease caused extreme lethargy in affected fish with few visible external signs. Mortalities either occurred gradually over the week from onset of clinical signs, or over a shorter period and in large numbers if fish were stressed. Consistent tissue changes were seen by light microscopy in the spleen, heart and kidney of affected fish. Electron microscopy showed viral particles associated with damage to cell organelles. In an experimental infection, apparently healthy fish cohabiting with an infected fish developed similar lesions and died. The significance of SGD in grouper culture is discussed.  相似文献   

The effect of inflammation on the disposition of phenylbutazone in Thoroughbred horses     

P. C. MILLS  J. C. NG  D. E. AUER† 《Journal of veterinary pharmacology and therapeutics》1996,19(6):475-481

The effect of inflammation on the disposition of phenylbutazone (PBZ) was investigated in Thoroughbred horses. An initial study ( n = 5) in which PBZ (8.8 mg/kg) was injected intravenously twice, 5 weeks apart, suggested that the administration of PBZ would not affect the plasma kinetics of a subsequent dose. Two other groups of horses were given PBZ at either 8.8 mg/kg ( n = 5) or 4.4 mg/kg ( n = 4). Soft tissue inflammation was then induced by the injection of Freud's adjuvant and the administration of PBZ was repeated at a dose level equivalent to, but five weeks later than, the initial dose. Inflammation did not appear to affect the plasma kinetics or the urinary excretion of PBZ and its metabolites, oxyphenbutazone (OPBZ) or hydroxyphenylbutazone (OHPBZ) when PBZ was administered at 8.8 mg/kg. However, small but significant increases ( P <0.05) in total body clearance ( CL _B; 29.2 ± 3.9 vs. 43.8 ± 8.1 mL/ h-kg) and the volume of distribution, calculated by area ( V _d(area); 0.18 ± 0.05 vs. 0.25 ± 0.03 L/kg) or at steady-state ( V _d(SS); 0.17±0.04 vs. 0.25 ± 0.03 L/ kg), were obtained in horses after adjuvant injection, compared to controls, when PBZ was administered at 4.4 mg/kg which corresponded to relatively higher tissues concentrations and lower plasma concentrations (calculated) at the time of maximum peripheral PBZ concentration. Soft tissue inflammation also induced a significantly ( P <0.05) higher amount of OPBZ in the urine 18 h after PBZ administration but the total urinary excretion of analytes over 48 h was unchanged. These results have possible implications regarding the administration of PBZ to the horse close to race-day.  相似文献   

Assessment of histamine, bradykinin, prostaglandins E₁ and E₂ and carrageenin as vascular permeability agents in the horse     

D. E. AUER  J. C. NG  J. S. REILLY  A. A. SEAWRIGHT 《Journal of veterinary pharmacology and therapeutics》1991,14(1):61-69

The vascular leakage induced by histamine, bradykinin, serotonin and prostaglandin E1 and E2 was assessed. The test agents were injected intradermally into the shaved thoracic skin of horses and the vascular leakage estimated either semi-quantitatively by recording the diameter of the lesions or by measuring the actual volume of extravasated plasma in microliters using iodine-125-labelled human serum albumin (125I-HSA) as a marker in the blood plasma. Using the latter method, the vascular leakage induced by carrageenin and the effect of coadministered prostaglandins E1 and E2 upon the vascular leakage of both histamine and bradykinin were also investigated. No obvious lesions resulted when serotonin (10(-2) mol/l) was injected but histamine and bradykinin produced circular lesions which increased in diameter for approximately 30 min. The size of the lesions and volume of extravasated plasma was dose dependent. On a molar basis, bradykinin (10(-6) mol/l, 10(-5) mol/l) was more potent than histamine but they were equipotent at 10(-4) mol/l. The size of the lesions induced by carrageenin were independent of their anatomical location on the thorax. Except for the second hour, the hourly volume of vascular leakage increased until the fifth hour when the experiment was concluded. The maximum vascular leakage resulting from the injection of prostaglandin E1 or E2 (1, 10, 100 or 1000 ng) was 7 microliters but when co-administered with bradykinin (10(-6) mol/l), the volume of leaked plasma increased from 29 to 78 microliters. No synergy was observed when either prostaglandin was co-administered with histamine (10(-5) mol/l).  相似文献