Evaluation of cinnamamide as an avian repellent: Determination of a dose—response curve     

Richard W. Watkins  Elaine L. Gill  Julie D. Bishop 《Pest management science》1995,44(4):335-340

The dose-response curve was quantified for the avian repellency of cinnamamide, a derivative of the plant secondary compound cinnamic acid, using a three-day, ‘short-term no-choice’ test. This test was designed to resemble more closely the availability of alternative food in the birds' natural environment than in previous no-choice studies. Cinnamamide reduced food consumption by feral pigeons (Columba livia Gmelin) at concentrations as low as 6.17 μmole g^?1 food (0.09% w/w) and this reduction increased with concentration. An R₅₀ index, the concentration at which food consumption was reduced by 50% was interpolated from the dose-response curve as 18.4 (±0.38) μmole g^?1 food 10.26% w/w). This index can now be matched with those of related compounds in future structure-activity studies. The birds' response to cinnamamide changed over the three-day trial with respect to concentration. Repellency declined at concentrations < R₅₀ and increased at concentrations > R₅₀. This suggests that pigeons become habituated to cinnamamide at low concentrations but at high concentrations they may develop a conditioned aversion. This study provides quantitative confirmation of previous laboratory and field demonstrations of cinnamamide's effectiveness as a non-lethal chemical repellent suitable for reducing avian pest damage.  相似文献   

Mode of action of the anilino-pyrimidine fungicide pyrimethanil. 2. Effects on enzyme secretion in Botrytis cinerea     

Richard J. Milling  Caroline J. Richardson 《Pest management science》1995,45(1):43-48

The effect of pyrimethanil on the levels of cell wall degrading enzymes secreted by Botrytis cinerea Pers. was investigated in diseased plant tissues and in liquid B. cinerea cultures. Total proteinase activity isolated from infected carrot slices which were treated with 5.0 μM pyrimethanil was decreased by 76%, 3 d after inoculation. Polygalacturonase, cellulase, proteinase and laccase activities were all decreased in the medium of three day-old cultures grown in the presence of pyrimethanil. The pyrimethanil concentrations resulting in 50% reduction in total enzyme activities (IC₅₀) were approximately 0.25 μM for polygalacturonase, cellulase and proteinase, and approximately 1.0 μM for laccase. No significant growth inhibition was observed at these pyrimethanil concentrations. Pyrimethanil did not inhibit the enzymes directly, nor did it inhibit the synthesis of cytosolic proteins. Therefore, it was proposed that the fungicide inhibits protein secretion at a post-translational stage in the secretory pathway. Large differences were found in the effects of pyrimethanil on the growth of B. cinerea in liquid cultures and on agar plates, depending on the composition of the medium. In liquid media containing cellulose and protein as carbon and nitrogen sources, growth inhibition occurred at 5.0 μM pyrimethanil, whilst no growth inhibition was observed with 50 μM pyrimethanil in malt extract. Similarly, growth occurred on potato/dextrose agar (PDA) at 0.5 μM pyrimethanil, but no growth was seen at this concentration on agars containing cellulose and protein. Thus it appears that pyrimethanil is most active in media where the fungus has to utilise extracellular enzymes to mobilise the nutrients it requires for growth.  相似文献   

Structure and general properties of mineral and vegetable oils used as spray adjuvants     

Richard J. Hamilton 《Pest management science》1993,37(2):141-146

The abiogenic and biosynthetic origins of mineral and vegetable oils are contrasted and the importance of soybean, palm, rape seed and sunflower as the major source of fatty acids is highlighted. The cheaper oils derived from animal sources also provide fatty acids. The extraction and refining processes for vegetable oils are explained, the composition of typical vegetable oils is discussed and the importance of the glyceride structure to the physical properties of the oils is emphasised. Stability, volatility and viscosity of vegetable oils are considered. Production of fatty acids by fat-splitting methods and the formation of methyl esters by inter-esterification are outlined. Mineral oil compositions are detailed and their properties explained.  相似文献   

Congenital internal hydrocephalus in a quarter horse foal     

Jonathan H. Foreman D.V.M.  Stephen M. Reed D.V.M.  Norman W. Rantanen D.V.M.  M.S.  Richard M. DeBowes D.V.M.  M.S.  Pamela C. Wagner D.V.M.  M.S. 《Journal of Equine Veterinary Science》1983,3(5):154-164

Since the normal absorption of CSF occurs in the cerebral veins and venous sinuses, any obstruction to the normal flow and absorption of CSF will result in accumulation of CSF central to the site of obstruction. Such accumulation within the cranium is defined as hydrocephalus.A foal was presented with an enlarged and an abnormally-shaped skull, but with normal behavior. The filly's condition deteriorated. Radiographs showed a domeshaped cranial vault with compression of the frontal sinus region. Massive hydrocephalus with little normal cerebral tissue left was diagnosed with ultrasound.Surgery was attempted to relieve the pressure. Eventually the foal was euthanized. Post-mortem confirmed the radiographic and ultrasound diagnosis. Since there was a lack of demonstrable obstruction, the authors suspected the foal had suffered from the Arnold-Chiari syndrome.  相似文献   

Book review     

Richard Matthewman 《Tropical animal health and production》1987,19(1):64-32

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Effect of methotrexate on rabbits infected with Mycobacterium paratuberculosis or Dermatophilus congolensis   总被引：1，自引：0，他引：1  

R S Merkal  J L Richard  J R Thurston  R D Ness 《American journal of veterinary research》1972,33(2):401-407

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The use of biodegradable polymers as formulating agents for controlled release pesticides     

Richard M. Wilkins 《Pest management science》1978,9(5):443-444

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Mycotoxin photosensitivity   总被引：1，自引：0，他引：1  

J L Richard 《Journal of the American Veterinary Medical Association》1973,163(11):1298-1299

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Studies on a fluorescent insect growth regulator metabolite complex with house-fly microsomal cytochrome P-450     

Richard T. Mayer  C.W. Fisher  J. Cocke  A.C. Bridges  J.K. Olson 《Pesticide biochemistry and physiology》1982,17(1):24-34

The fluorescent insect growth regulator 5[[[5-(dimethylamino)-1-naphthalenyl]amino]-1,3-benzodioxole (DNSAB) forms a metabolite complex with house-fly microsomal cytochrome P-450. Formation of the metabolite complex is dependent on the presence of NADPH and O₂; NADH supports the reaction at a reduced rate. The presence of antibodies to house-fly cytochrome c (P-450) reductase in reaction mixtures inhibits the complex formation, indicating that the reductase is necessary for transfer of electrons from NADPH to cytochrome P-450 to complete the reaction. In the oxidized form, the metabolite complex has a single absorbance maximum at 431 nm, whereas the reduced form has two absorbance maxima at 426 (major) and 455 nm (minor). The pH of the media affects the extinction of the 426- and 455-nm Soret bands; increased pH decreases the extinction of the 426-nm band and increases the extinction of 455-nm band. Formation of the DNSAB metabolite-cytochrome P-450 complex decreases the amount of CO-reactive cytochrome P-450 by 24%. The metabolite complex is not dissociable by treatment with ferricyanide or by using centrifugation techniques. Dissociation is accomplished by addition of DNSAB to the oxidized metabolite complex. Kinetic analysis of the complex formation gives apparent K_m and V_max values at 2.55 ± 1.0 μM and 1.1 ± 0.4 × 10^?2 ΔA min^?1 nmol^?1 cytochrome P-450, respectively. Addition of juvenile hormone [(E,E)-cis-methyl-10,11-epoxy-7-ethyl-3,11-dimethyl-2,6-tridecadienoate; JH] to the reaction medium competitively inhibits the formation of the metabolite complex giving an inhibition constant of 16 μM. DNSAB synergized the lethal effects of JH against Aedes aegypti larvae threefold; however, JH did not synergize DNSAB. These data suggest that DNSAB may acquire its hormonal qualities by complexing a species of cytochrome P-450 that metabolizes JH, thereby prolonging the in vivo lifetime of this hormone.  相似文献   

Crooked calf syndrome, a plant-induced congenital deformity     

James L.  Shupe D.V.M.  Wayne  Binns D.V.M.  Lynn F.  James Ph.D. Richard F.  Keeler Ph.D. 《Reproduction in domestic animals》1967,2(4):145-152

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