铬在增强畜禽抗应激与免疫机能中的作用   总被引：3，自引：0，他引：3  

许毅  冯三令等 《家畜生态》2003,24(1):63-65

铬是动物所必需的一种微量元素，在动物体内碳水化合物，蛋白质，脂肪的代谢起重要作用。近年来研究发现铬的抗应激和提高免疫机能上有特殊的作用。本文就这一热点问题进行综述。  相似文献   

Pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin after intravenous and oral administration of enrofloxacin in dogs   总被引：9，自引：0，他引：9  

K. KÜNG  J.-L. RIOND  M. WANNER 《Journal of veterinary pharmacology and therapeutics》1993,16(4):462-468

Rung, K., Riond, J.-L. & Wanner, M. Pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin after intravenous and oral administration of enrofloxacin in dogs. J. vet
Four dogs were given 5 mg/kg body weight enrofloxacin intravenously (i.v.) and orally (p.o.) in a cross-over study. Plasma concentrations of the active ingredient enrofloxacin and its main metabolite ciprofloxacin were determined by a reversed phase liquid chromatographic method. Pharmacokinetic parameters of both substances were calculated by use of statistical moments and were compared to those of enrofloxacin described in the veterinary literature. Mean enrofloxacin t _½λZ was 2.4 h, mean Cl_s was 27.1 ml/min-kg, and mean V_ss was 7.0 1/kg. After i.v. and p.o. administration, concentrations of ciprofloxacin exceeding minimal inhibitory concentrations of several microorganisms were reached (C_max= 0.2 ng/ml, max = 2.2 h after intravenous administration; C_max= 0.2 (ig/ml, t _max= 3.6 h after oral administration). A considerable part of the antimicrobial activity is due to ciprofloxacin, the main metabolite of enrofloxacin.  相似文献   

Sectional notes     

Evans  H. J.  Henderson  C. A.  Burke  O. D.  Noonan  John  Harris  M. R.  Scannell  J. W. 《American Journal of Potato Research》1948,25(11):417-421

American Journal of Potato Research -  相似文献   

The ability of biochemical and haematological tests to predict recovery in periparturient recumbent cows     

Clark RG  Henderson HV  Hoggard GK  Ellison RS  Young BJ 《New Zealand veterinary journal》1987,35(8):126-133

Blood samples from 433 periparturient recumbent cows submitted by veterinary practitioners to Ruakura Animal Health Laboratory during 1983 and 1984 were analysed and results related to whether cows recovered, died or were euthanased. Generally cows were sampled only once and the time varied from 15 minutes to 20 days after becoming recumbent. During 1983 serum calcium, magnesium, phosphorus, creatine phosphokinase (CK), aspartate amino transferase (AST), glutamate dehydrogenase (GDH), gamma glutamyl transferase (GGT) were analysed. In 1984 serum urea, creatinine, fibrinogen and haematological examination (haemoglobin, haematocrit, total and differential white cell counts) were added to the panel. Overall 39% of cows recovered, 30% died and 32% were destroyed. Precalving cows had 111% more deaths and 7% less survivors than postcalving recumbent cows (P<0.1). There was little difference (3%) in euthanasia prevalence. Tests that were most useful in predicting a lack of recovery were serum urea and muscle enzymes. Using these tests and duration of recumbency when sampled a model was produced to predict the probability of recovery from 254 cases.  相似文献   

Preliminary observations on the occurrence of the equine XO syndrome.     

A N Bruère  M G Blue  P M Jaine  K S Walker  L M Henderson  H M Chapman 《New Zealand veterinary journal》1978,26(6):145-146

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A study of the mechanical properties of egg shell     

L. H. Nelson  J. M. Henderson 《British poultry science》1975,16(3):225-239

1. The mechanical behaviour of the egg shell of the domestic fowl was investigated by cutting strips from the shell and testing the flection either in a four‐point load test or in a cantilever beam test.

2. It was found that moisture content, temperature and load rate have important effects on shell properties ; both the strength and stiffness of the shell are greater in snapping‐inward tests than in snapping‐outward tests; residual stress exists in the egg shell; the correlation between failure moment and shell thickness was highly significant, on average about 0.9, and was dependent on the spread in the thickness data.

3. Estimates were made of the ultimate strength and Young's modulus of egg shell material and it is concluded that a substantial size effect exists in the egg shell.  相似文献   

A comparison of rapid bovine spongiform encephalopathy testing methods on autolyzed bovine brain tissue.     

Angus Wear  Kirstine Henderson  Kath Webster  Indu Patel 《Journal of veterinary diagnostic investigation》2005,17(2):99-102

In 1999, the European Union (EU) approved 3 rapid methods for the testing of bovine brain samples for the presence of bovine spongiform encephalopathy (BSE). The evaluation that led to the approval did not include an analysis of autolyzed material. Member states of the EU have active surveillance programs for BSE, which target fallen stock as well as other categories of cattle. Autolysis is a common feature of fallen stock samples because there can be a considerable delay between death and collection of samples. Therefore, it is important to know whether these tests perform optimally on autolyzed samples. The Veterinary Laboratories Agency (VLA) selected 250 positive fallen stock samples. These had been detected during routine testing using the Prionics-Check Western blot and confirmed as BSE cases by immunohistochemistry or electron microscopy. Samples were graded according to the degree of autolysis and then tested by the 3 methods: Prionics-Check Western blot, Platelia test, and Enfer test. All 3 methods correctly classified the samples as positive BSE cases, therefore alleviating doubt about their ability to do so. Subsequent EU validation exercises, such as those conducted in 2002--2003, have included the testing of autolyzed material. It is important that all new methods be evaluated on autolyzed tissue before approval for official use.  相似文献   

Key Factors Affecting Reproductive Success of Thoroughbred Mares and Stallions on a Commercial Stud Farm          下载免费PDF全文

EA Lane  MLJ Bijnen  M Osborne  SJ More  ISF Henderson  P Duffy  MA Crowe 《Reproduction in domestic animals》2016,51(2):181-187

To evaluate factors contributing to fertility of thoroughbred mares, data from 3743 oestrous periods of 2385 mares were collected on a large thoroughbred farm in Ireland. Fourteen stallions (mean age 8.3 years; range 4–15 years) had bred 2385 mares (mean age 9.4 years; range 3–24 years). Maiden mares accounted for 12%, mares with a foal at foot for 64%, and barren, slipped or rested mares for 24% of the total. The mean pregnancy rate per cycle was 67.8% (68.6% in year 1 and 66.9% in year 2). Backward stepwise multivariable logistic regression analysis was utilized to develop two models to evaluate mare factors, including mare age, reproductive status, month of foaling, dystocia, month of cover, foal heat, cycle number, treatments, walk‐in status and stallion factors including stallion identity, stallion age, shuttle status, time elapsed between covers and high stallion usage on the per cycle pregnancy rate and pregnancy loss. Old age (p < 0.001) and cover within 20 days post‐partum (p < 0.003) were associated with lowered pregnancy rates. High mare age (p < 0.05) and barren, slipped or rested reproductive status (p = 0.05) increased the likelihood of pregnancy loss. Uterine inflammation or infection, if appropriately treated, did not affect fertility. Only high usage of stallions (used more than 21 times in previous week) was associated with lowered (p = 0.009) pregnancy rates. However, shuttle stallions were more likely to have increased (p = 0.035) pregnancy survival, perhaps reflecting a bias in stallion selection. In conclusion, mare age exerted the greatest influence on fertility; nonetheless, thoroughbreds can be effectively managed to achieve high reproductive performance in a commercial setting.  相似文献   

聚乙二醇诱导水分胁迫引起水稻光合下降的原因探讨   总被引：30，自引：1，他引：30  

孙骏威  杨勇  黄宗安  金松恒  蒋德安 《中国水稻科学》2004,18(6):539-543

在水稻品种Azucena(粳稻)6叶期用不同浓度的聚乙二醇(PEG 6000)模拟干旱处理,结果表明,随着PEG处理浓度提高,净光合速率（Pn）呈下降趋势, 但各阶段起主导作用的因素不同。第一阶段, 在10%PEG处理下Pn显著下降,色素和叶绿素荧光保持不变,气孔导度(Gs)和胞间CO2浓度(Ci)反而上升,表明为非气孔因子限制光合速率;第二阶段,在15%PEG处理下色素和叶绿素荧光虽开始变化,Pn继续降低, 并伴随Gs和Ci的下降而下降,因此气孔导度成为光合速率的主要限制因子;第三阶段,在20%PEG处理下Pn继续降低,Gs虽下降,但Ci并没有进一步下降,而色素和荧光参数均进一步下降,此时光合膜的损伤成为限制光合的主导因子。上述结果表明,严重水分胁迫虽使光合机构吸收和传递光能效率下降,但过剩的激发能仍可能导致活性氧积累;尽管水稻叶内启动了超氧化物防御系统,但仍能导致光合器官受损及PSⅡ光化学活性降低。  相似文献   

黄瓜根腐病致病病原的鉴定   总被引：6，自引：0，他引：6  

王惠哲  李淑菊  马德华  董金皋 《华北农学报》2003,18(2):74-77

在天津市及周边地区采集病株进行组织分离，同时分离到两类病原菌，经初步的生物学特性鉴定表明，引起黄瓜根腐病的主要病原菌为甜瓜疫霉、尖孢镰刀菌和茄病镰刀菌。经接种试验，认为甜瓜疫霉为主要致病菌。  相似文献