Endoscopic sex determination and gonadal manipulation in Gulf of Mexico sturgeon (Acipenser oxyrinchus desotoi).     

Stephen J Hernandez-Divers  Robert S Bakal  Brian H Hickson  Clarence A Rawlings  Heather G Wilson  MaryAnn Radlinsky  Sonia M Hernandez-Divers  Samuel R Dover 《Journal of zoo and wildlife medicine》2004,35(4):459-470

Seventeen Gulf of Mexico sturgeons (Acipenser oxyrinchus desotoi) underwent endoscopic sex determination, gonadal biopsy, and various reproductive surgeries as part of a conservation development plan. The fish were anesthetized with tricaine methanesulfonate (MS-222) buffered with sodium bicarbonate and maintained on a recirculating water anesthesia circuit. A 6-mm Ternamian EndoTip Cannula, placed through the ventral midline, midway between pectoral and pelvic fins, permitted the introduction of a 5-mm telescope. Swim bladder aspiration and CO2 insufflation of the coelomic cavity provided excellent observation. Second and third cannulae were placed under direct visual control, lateral and cranial or caudal to the telescope cannula. Sex determination was successfully performed in all fish; however, five of 17 sturgeons (29%) required endoscopic gonadal biopsy to confirm sex. Bilateral ovariectomy or orchidectomy was successfully performed in three males and four females. Unilateral ovariectomy and bilateral ligation of the müllerian ducts using an extracorporeal suturing technique was accomplished in an additional three females. No apparent morbidity was associated with the anesthesia or endoscopic surgery in any fish. The ability to safely perform minimally invasive reproductive surgery in fish may have important management and conservation benefits.  相似文献   

Time-frequency and complexity analyses for differentiation of physiologic murmurs from heart murmurs caused by aortic stenosis in Boxers   总被引：1，自引：0，他引：1  

Höglund K  Ahlstrom CH  Häggström J  Ask PN  Hult PH  Kvart C 《American journal of veterinary research》2007,68(9):962-969

OBJECTIVE: To investigate whether time-frequency and complexity analyses of heart murmurs can be used to differentiate physiologic murmurs from murmurs caused by aortic stenosis (AS) in Boxers. ANIMALS: 27 Boxers with murmurs. PROCEDURES: Dogs were evaluated via auscultation and echocardiography. Analyses of time-frequency properties (TFPs; ie, maximal murmur frequency and duration of murmur frequency > 200 Hz) and correlation dimension (T(2)) of murmurs were performed on phonocardiographic sound data. Time-frequency property and T(2) analyses of low-intensity murmurs in 16 dogs without AS were performed at 7 weeks and 12 months of age. Additionally, TFP and T(2) analyses were performed on data obtained from 11 adult AS-affected dogs with murmurs. RESULTS: In dogs with low-intensity murmurs, TFP or T(2) values at 7 weeks and 12 months did not differ significantly. For differentiation of physiologic murmurs from murmurs caused by mild AS, duration of murmur frequency > 200 Hz was useful and the combination assessment of duration of frequency > 200 Hz and T(2) of the murmur had a sensitivity of 94% and a specificity of 82%. Maximal murmur frequency did not differentiate dogs with AS from those without AS. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that assessment of the duration of murmur frequency > 200 Hz can be used to distinguish physiologic heart murmurs from murmurs caused by mild AS in Boxers. Combination of this analysis with T(2) analysis may be a useful complementary method for diagnostic assessment of cardiovascular function in dogs.  相似文献   

Effect of glyphosate on the tripartite symbiosis formed by Glomus intraradices,Bradyrhizobium japonicum,and genetically modified soybean     

Jeff R. Powell  Rachel G. Campbell  Kari E. Dunfield  Robert H. Gulden  Miranda M. Hart  David J. Levy-Booth  John N. Klironomos  K. Peter Pauls  Clarence J. Swanton  Jack T. Trevors  Pedro M. Antunes 《Applied soil ecology》2009,41(1):128-136

Most soybeans grown in North America are genetically modified (GM) to tolerate applications of the broad-spectrum herbicide glyphosate; as a result, glyphosate is now extensively used in soybean cropping systems. Soybean roots form both arbuscular mycorrhizal (AM) and rhizobial symbioses. In addition to individually improving host plant fitness, these symbioses also interact to influence the functioning of each symbiosis, thereby establishing a tripartite symbiosis. The objectives of this study were to (1) estimate the effects of glyphosate on the establishment and functioning of AM and rhizobial symbioses with GM soybean, and (2) to estimate the interdependence of the symbioses in determining the response of each symbiosis to glyphosate. These objectives were addressed in two experiments; the first investigated the importance of the timing of glyphosate application in determining the responses of the symbionts and the second varied the rate of glyphosate application. Glyphosate applied at recommended field rates had no effect on Glomus intraradices or Bradyrhizobium japonicum colonization of soybean roots, or on soybean foliar tissue [P]. N₂-fixation was greater for glyphosate-treated soybean plants than for untreated-plants in both experiments, but only when glyphosate was applied at the first trifoliate soybean growth stage. These data deviate from previous studies estimating the effect of glyphosate on the rhizobial symbiosis, some of which observed negative effects on rhizobial colonization and/or N₂-fixation. We did observe evidence of the response of one symbiont (stimulation of N₂-fixation following glyphosate) being dependent on co-inoculation with the other; however, this interactive response appeared to be contextually dependent as it was not consistent between experiments. Future research needs to consider the role of environmental factors and other biota when evaluating rhizobial responses to herbicide applications.  相似文献   

Effect of E. coli ectotoxin on calcium and phosphate concentration in serum of dairy cows     

H Sandstedt  L Larsson  C Kvart 《Nordisk veterinaermedicin》1984,36(11):406-407

The injection of E. coli ectotoxin into eight healthy cows of the SRB breed induced a significant hypocalcemia and hypophosphatemia. A clinical profile similar to that normally seen in paresis puerperalis was also observed. These results confirm earlier observations that toxaemia can give rise to paralytic symptoms.  相似文献   

Pulmonary Arteriography and Hemodynamics During Feline Heartworm Disease     

Clarence A. Rawlings DVM  PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1990,4(6):285-291

The ability of aspirin to block arterial disease and thromboembolism of the pulmonary arteries was studied in heartworm-infected cats. Three groups of cats were transplanted with four heartworms per cat and studied. One group of eight cats (aspirin group) received aspirin (97.5 mg, twice a week) for the five-month infection and another group of eight cats served as the nontreated control group (nontreated group). Based upon the results of the first two groups, the third group (adjusted aspirin group) of six cats was studied in which the aspirin dosage was adjusted in order to maintain an inhibition of in vitro platelet aggregation. Cats were studied by nonselective pulmonary arteriograms before heartworm transplantation and by selective arteriograms, aortograms, and pulmonary hemodynamics five months after heartworm transplant. Pulmonary hypertension, (mean pulmonary artery pressures greater than 16 mmHg), was discovered in three cats with one cat in each group. There were no differences in the mean pulmonary artery pressure or vascular resistance between the groups. Many of the arterial diameters for the nontreated and aspirin groups were greater after the five-month infection than before heartworm infection. All of the postinfection caudal arteries were tortuous and had aneurysms. Some of the caudal lung lobes had perfused areas that appeared to have a hypervascular microvasculature. The proportion of obstructed right and left distal caudal pulmonary arteries and the resulting nonperfused area of the caudal lung lobe in the nontreated and aspirin treated groups were each greater than in the adjusted aspirin group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

Reduced high intensity training distance had no effect on VLa4 but attenuated heart rate response in 2-3-year-old Standardbred horses     

Sara Ringmark  Arne Lindholm  Ulf Hedenstr?m  Michael Lindinger  Kristina Dahlborn  Clarence Kvart  Anna Jansson 《Acta veterinaria Scandinavica》2015,57(1)

Background

Training of Standardbred race horses aims to improve cardiovascular and metabolic functions but studies on the effects of different training strategies from breaking till racing are lacking. Sixteen horses with the goal to race as 3-year-olds were studied from breaking (1-year-olds) to December as 3-year-olds. Horses were allocated to either a control (C) or reduced (R) training program from 2 years of age. The aim was to evaluate the effect of reducing the distance of high intensity exercise by 30% with respect to velocity at lactate concentration 4 mmol/l (V_La4), blood lactate and cardiovascular response. All training sessions were documented and heart rate (HR) was recorded. A standardized exercise test of 1,600 m was performed 10 times and a V_La4 test was performed five times.

Results

C horses initially exercised for a longer time with a HR >180 beats per minute compared to R horses (P < 0.05) but after 6–9 months, time with HR >180 bpm decreased in C and were similar in the two groups (P > 0.05). Over the 2-year period, recovery HR after the 1,600 m-test decreased in both groups but was within 2 months lower in C than in R (P < 0.05). C horses also had lower resting HR as 3-year-olds (P < 0.01) than R horses. In C, post exercise hematocrit was higher than in R (P < 0.05). There was a tendency (P < 0.1) towards a larger aortic diameter in C as 3-year-olds (C: 1.75 ± 0.05, R: 1.70 ± 0.05 cm/100 kg BW). Left ventricle diameter and blood volume (in December as 2-year-olds) did not differ between groups. There were no differences between groups in post exercise blood lactate concentration or in V_La4. Both groups were equally successful in reaching the goal of participation in races.

Conclusions

Horses subjected to a reduced distance of high intensity training from the age of 2 showed an attenuated heart rate response, but were able to maintain the same V_La4 and race participation as horses subjected to longer training distances.  相似文献   

Quantification and persistence of recombinant DNA of Roundup Ready corn and soybean in rotation     

Lerat S  Gulden RH  Hart MM  Powell JR  England LS  Pauls KP  Swanton CJ  Klironomos JN  Trevors JT 《Journal of agricultural and food chemistry》2007,55(25):10226-10231

The presence of the recombinant cp4 epsps gene from Roundup Ready (RR) corn and RR soybean was quantified using real-time PCR in soil samples from a field experiment growing RR and conventional corn and soybean in rotation. RR corn and RR soybean cp4 epsps persisted in soil for up to 1 year after seeding. The concentration of recombinant DNA in soil peaked in July and August in RR corn and RR soybean plots, respectively. A small fraction of soil samples from plots seeded with conventional crops contained recombinant DNA, suggesting transgene dispersal by means of natural process or agricultural practices. This research will aid in the understanding of the persistence of recombinant DNA in agricultural cropping systems.  相似文献   

Book reviews     

Edward N Ziegler  G. F. Humphrey  Arthur C. Stern  Clarence G. Golueke  Elmer Robinson  T. Viraraghavan 《Water, air, and soil pollution》1979,11(3):401-405

  相似文献   

Quantitation of transgenic plant DNA in leachate water: real-time polymerase chain reaction analysis     

Gulden RH  Lerat S  Hart MM  Powell JR  Trevors JT  Pauls KP  Klironomos JN  Swanton CJ 《Journal of agricultural and food chemistry》2005,53(15):5858-5865

Roundup Ready (RR) genetically modified (GM) corn and soybean comprise a large portion of the annual planted acreage of GM crops. Plant growth and subsequent plant decomposition introduce the recombinant DNA (rDNA) into the soil environment, where its fate has not been completely researched. Little is known of the temporal and spatial distribution of plant-derived rDNA in the soil environment and in situ transport of plant DNA by leachate water has not been studied before. The objectives of this study were to determine whether sufficient quantities of plant rDNA were released by roots during growth and early decomposition to be detected in water collected after percolating through a soil profile and to determine the influence of temperature on DNA persistence in the leachate water. Individual plants of RR corn and RR soybean were grown in modified cylinders in a growth room, and the cylinders were flushed with rain water weekly. Immediately after collection, the leachate was subjected to DNA purification followed by rDNA quantification using real-time Polymerase Chain Reaction (PCR) analysis. To test the effects of temperature on plant DNA persistence in leachate water, water samples were spiked with known quantities of RR soybean or RR corn genomic DNA and DNA persistence was examined at 5, 15, and 25 degrees C. Differences in the amounts and temporal distributions of root-derived rDNA were observed between corn and soybean plants. The results suggest that rainfall events may distribute plant DNA throughout the soil and into leachate water. Half-lives of plant DNA in leachate water ranged from 1.2 to 26.7 h, and persistence was greater at colder temperatures (5 and 15 degrees C).  相似文献   

Räumliche Spannungsmessungen mit dem Stress State Transducer (SST) in ungesättigten aggregierten Böden - theoretische Betrachtungen und erste Ergebnisse     

Rainer Horn  Clarence  Johnson  Harald Semmel  Robert Schafer  Matthias Lebert 《植物养料与土壤学杂志》1992,155(4):269-274

Stress measurements in undisturbed unsaturated soils with a Stress State Transducer (SST) - theory and first results A method to quantify the spatial stress distribution will be introduced and first results will be discussed. This method allows the detailed analysis of principal and shear stresses as well as the determination of the direction angle of principal stresses and the octahedral shear stress angle. The described Stress State Transducer (SST) is composed of six single strain gage sensors that enable the accurate and reproducable recording of stresses in six directions in a wide load range. Their data form the base for calculation of spatial stress distribution. Some first results show that in a luvisol derived from loess wheeling at a wheel load of 4.0 Mg induces high shear stresses in a depth of 30 cm. This probably causes plastic soil deformation.  相似文献