Tissue culture technology: Practical application of sophisticated methods     

John H. Dodds 《American Journal of Potato Research》1988,65(4):167-180

  相似文献   

Naturally occurring and experimental Stachys arvensis (staggerweed) toxicity in lambs in New Zealand     

BL Vaatstra  KG Thompson  FI Hill  MT Walshe  ML Gilmour 《New Zealand veterinary journal》2013,61(3)

Stachys arvensis (staggerweed) is a common, widely distributed weed of cultivated and waste land with the potential to intoxicate sheep. Two naturally occurring outbreaks of suspected staggerweed toxicity in the lower North Island were investigated. Affected lambs had been recently moved onto staggerweed-contaminated Brassica spp. crops. In total, 150/1,200 (13%) lambs developed hindlimb paresis, a fine generalised muscular tremor, and hunched posture. When forced to move, many became recumbent. Most lambs recovered within 48 h of removal from staggerweed, although a few developed clinical signs again when transported 2–3 weeks later. Grossly, affected lambs had large amounts of staggerweed plant material and seeds within the rumen. Histopathology showed mild, multifocal degeneration of the white matter tracts of the central nervous system (CNS), most commonly in the ventral funiculi of the spinal cord, and acute, mild to moderate, multifocal degeneration of skeletal muscles. Creatine kinase (CK) activity in serum was mildly to markedly elevated in affected lambs. In a feeding trial, ten 10-month-old Romney lambs were randomly assigned to equal treatment and control groups. Treated lambs were drenched with a liquid extract of staggerweed once daily for 7 days. Three of five treated lambs developed mild exercise intolerance, and 1/5 displayed mild paresis of the hindlimbs, slightly crouched hindlimb stance, and shortened gait, on days 6 and 7. Histologically, 4/5 treated lambs had degeneration in white matter tracts of the CNS, indistinguishable from those seen in the lambs in the outbreak, and in 1/5 lambs there was scattered regeneration of skeletal muscle. CK activity in serum in treated lambs was not significantly higher than that in control lambs. None of the control lambs developed significant clinical signs, histological changes or increases in CK activity in serum. The clinical signs and lesions observed in both the outbreaks and feeding trial were similar to those previously described in studies in Australia, with the exception that myodegeneration was more prominent in the outbreaks in New Zealand. Further characterisation of the pathogenesis of staggerweed toxicity and its potential role as a food safety hazard will be facilitated through identification of the toxic principle(s).  相似文献   

Spray droplet size and carrier volume effect on dicamba and glufosinate efficacy          下载免费PDF全文

Thomas R Butts  Chase A Samples  Lucas X Franca  Darrin M Dodds  Daniel B Reynolds  Jason W Adams  Richard K Zollinger  Kirk A Howatt  Bradley K Fritz  Wesley Clint Hoffmann  Greg R Kruger 《Pest management science》2018,74(9):2020-2029

  相似文献   

Efficiency and precision of electroimmunoassay for canine factor VIII-related antigen   总被引：2，自引：0，他引：2  

R E Benson  D W Jones  W J Dodds 《American journal of veterinary research》1983,44(3):399-403

Factors that improved the efficiency, precision, and sensitivity of the electroimmunoassay for canine factor VIII-related antigen were investigated. These included rapid electrophoresis, increased rocket heights, deletion of the gel-washing step, and doubling of the sample capacity per plate. The modified assay was reliable and accurate, could be completed within 3 hours, and permitted twice as many determinations. Other experimental variables that affected the assay were the type of agarose and sample diluent, storage conditions of samples before assay, source of antibody, and use of 2 mM calcium lactate.  相似文献   

Coagulation changes in African swine fever virus infection   总被引：1，自引：0，他引：1  

J F Edwards  W J Dodds  D O Slauson 《American journal of veterinary research》1984,45(11):2414-2420

Pigs were infected with highly virulent (Tengani '62), with moderately virulent (DR '79) African swine fever (ASF) virus, or with virulent hog cholera (HC) virus. Changes in platelet counts, selected coagulation assays and concentrations of factor VIII-related antigen (VIIIR:Ag) were monitored. Permeability of aortic endothelium was studied after the injection of Evan's blue dye on various days after infection with DR '79 ASF virus. Virulent ASF virus caused prolongation of the activated partial thromboplastin time (APTT), 1-stage prothrombin time, and thrombin clotting time as early as postinoculation day (PID) 4. These changes became progressively more severe until death. Both virulent HC and DR'79 viruses induced an increase APPT and thrombin clotting time at PID 3 to 4, only occasionally did the prothrombin time increased significantly (P less than 0.01). The APPT began to decrease on PID 7 and 8, but only DR'79-infected pigs lived long enough to regain a normal APTT. Infection by ASF viruses caused acute thrombocytopenia after PID 6 and platelet counts of HC virus-infected pigs decreased progressively from the onset of fever to levels of 1 to 2 X 10(5)/mm3 at PID 6 to 7. All ASF virus-infected pigs had an increase in VIIIR:Ag beginning at PID 3, with maximum increases at PID 6 to 7. Hog cholera virus infection did not cause consistent changes in levels of VIIIR:Ag. Pigs infected with DR'79 virus did not have increased vascular permeability to Evan's blue dye during infection; however, there was markedly decreased staining of the aorta after pigs became thrombocytopenic.  相似文献   

Contributions and future directions of hemostasis research     

W J Dodds 《Journal of the American Veterinary Medical Association》1988,193(9):1157-1160

  相似文献   

Immunosuppressive drug therapy.          下载免费PDF全文

W J Dodds 《The Canadian veterinary journal. La revue veterinaire canadienne》1996,37(3):133

  相似文献   

Effects of drug residues in the faeces of cattle treated with injectable formulations of ivermectin and moxidectin on larvae of the bush fly, Musca vetustissima and the house fly, Musca domestica     

KG WARDHAUGH  P. HOLTER  WA WHITBY  K. SHELLEY 《Australian veterinary journal》1996,74(5):370-374

Objective: To assess the toxicity of residues of ivermectin and moxidectin in cattle faeces collected at intervals after treatment.
Design: Replicated bioassays of faeces using larvae of the bush fly, Musca vetustissima and the house fly, Musca domestica .
Animals: Two groups of five Murray Grey x Aberdeen Angus steers were treated with injectable formulations of ivermectin and moxidectin respectively. A third group was used as an untreated control.
Procedure: Newly emerged fly larvae were reared in the dung of treated animals.
Results: Drug residues in faeces collected 3 to 35 days after treatment with an injectable formulation of moxidectin had no significant effect on the survival of larvae of M vetustissima . Similarly, faeces dropped up to seven days after treatment caused no significant reduction in larval survival in M domestica . In day 2 dung, residues of moxidectin delayed development of M vetustissima larvae, but had no effect on their survival. In contrast, ivermectin-treated steers, produced dung that inhibited larval development of both M vetustissima and M domestica for 7 to 14 days after treatment. Significant reductions in survival of M vetustissima larvae occurred in dung collected on days 21 and 28 after treatment, but by day 35 survival did not differ from that in control dung.
Conclusion: Excreted faecal residues of moxidectin are relatively innocuous to larvae of both M vetustissima and M domestica . Those of ivermectin inhibit survival for 7 to 14 days after treatment and are likely to have adverse effects on non-target organisms.  相似文献   

Clinical and laboratory features of a severe form of von Willebrand disease in Shetland sheepdogs   总被引：1，自引：0，他引：1  

S L Raymond  D W Jones  M B Brooks  W J Dodds 《Journal of the American Veterinary Medical Association》1990,197(10):1342-1346

Ten clinically affected Shetland Sheepdogs were evaluated to define their severe bleeding diathesis and were determined to have von Willebrand factor antigen (vWF:Ag) values less than 0.1% by ELISA assay. The virtual absence of vWF protein by ELISA assay and on multimeric analysis was diagnostic of either homozygosity or probable double heterozygosity for the canine von Willebrand disease (vWD) gene. Clinically affected dogs have type-III vWD and are the offspring of 2 heterozygous parents carrying type-I vWD. Twenty-three percent (1,428 dogs) of the more than 6,000 Shetland Sheepdogs screened for vWD at our facility since 1982 tested within the heterozygous carrier range for the common type-I form of this inherited disorder. Veterinarians and breeders should be aware of the potential for bleeding associated with elective and medical procedures in Shetland Sheepdogs and should use caution when breeding carriers of vWD because of the risk of producing clinically affected offspring with severe type-III vWD.  相似文献   

Progressive ataxia associated with degenerative thoracic myelopathy in Merino sheep     

PAW HARPER †  JW PLANT  KH WALKER  KG TIMMINS† 《Australian veterinary journal》1991,68(11):357-358

A neurological disorder in Merino sheep, characterised clinically by progressive posterior ataxia and microscopically by Wallerian degeneration in thoracic segments of the spinal cord, is described. Animals of both sexes were affected, with the earliest onset of disease being at 5 months of age. Most affected animals died before 2 years of age. The clinical, pathological and epidemiological features suggest that this degenerative thoracic myelopathy is a previously unrecognised entity differing from other reported causes of ataxia in sheep in Australia.  相似文献