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61.
Neonicotinoids represent a class of insect-selective ligands of nicotinic acetylcholine receptors. Imidacloprid, the first commercially used neonicotinoid insecticide, has been studied on neuronal preparations from many insects to date. Here we report first intrinsic binding data of thiamethoxam, using membranes from Myzus persicae Sulzer and Aphis craccivora Koch. In both aphids, specific binding of [3H]thiamethoxam was sensitive to temperature, while the absolute level of non-specific binding was not affected. In M persicae, binding capacity (Bmax) for [3H]thiamethoxam was ca 450 fmol mg(-1) of protein at 22 degrees C and ca 700 fmol mg(-1) of protein at 2 degrees C. The negative effect of increased temperature was reversible and hence not due to some destructive process. The affinity for [3H]thiamethoxam was less affected by temperature: Kd was ca 11 nM at 2 degrees C and ca 15 nM at 22 degrees C. The membranes also lost binding sites for [3H]thiamethoxam during prolonged storage at room temperature, and upon freezing and thawing. In A craccivora, [3H]thiamethoxam was bound with a capacity of ca 1000 fmol mg(-1) protein and an affinity of ca 90 nM, as measured at 2 degrees C. Overall, the in vitro temperature sensitivity of [3H]thiamethoxam binding was in obvious contrast to the behaviour of [3H]imidacloprid studied in parallel. Moreover, the binding of [3H]thiamethoxam was inhibited by imidacloprid in a non-competitive mode, as shown with M persicae. In our view, these differences demonstrate that thiamethoxam and imidacloprid, which represent different structural sub-classes of neonicotinoids, do not share the same binding site or mode. This holds also for other neonicotinoids, as we report in a companion article. 相似文献
62.
63.
Blazyczek I Hamann H Ohnesorge B Deegen E Distl O 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(7-8):346-351
The objective of the present study was to analyse the importance of the influences of sex, inbreeding coefficient, proportion of genes of the original breeds and the additive genetic contribution to the occurrence of guttural pouch tympany in foals belonging to German Warmblood breeds. Foals affected by guttural pouch tympany were ascertained in the Clinic of Horses, School of Veterinary Medicine Hannover. This data set comprised 22 German Warmblood foals with guttural pouch tympany, which were patients of the Clinic for Horses between 1994 and 2001. Information on the pedigrees and all available relatives of these patients allowed us to group the affected foals into five families with a total of 289 animals. Female foals were significantly more often affected by guttural pouch tympany. The difference was 16.6% in favour of female foals. The size of the inbreeding coefficient was not important for the occurrence of guttural pouch tympany. The proportion of the genes of the breeds Arabian, Thoroughbred and Trakehner were not significantly different from a randomly selected sample of 10% of foals born in the same birth years and the same region. The heritability estimates for the frequency of guttural pouch tympany using a threshold model was 0.81 +/- 0.16. This is the first report that could show a genetic component responsible for guttural pouch tympany in horses. 相似文献
64.
Henning A Haga DVM Asbjoern Tevik DVM MS & Henning Moerch 《Veterinary anaesthesia and analgesia》2002,29(2):69-75
Objective To investigate motor responses to stimulation during the transition from ‘deep’ (burst suppression) to ‘light’ isoflurane anaesthesia in pigs. Study design Prospective, randomized observational study. Animals Five castrated male and five female Norwegian landrace pigs, weighing 19–29 kg. Materials and methods Anaesthesia was induced with isoflurane and the inspired concentration gradually increased until a burst suppression electroencephalogram (EEG) was recorded. End‐tidal isoflurane concentration ( F ) was then allowed to equilibrate for 30 minutes after which the eyelashes, cornea, nasal septum, anus, interdigital skin fold, periople, tail and claw were stimulated. The motor response to stimulation at each location was graded from 0 to 5. End‐tidal isoflurane concentration was decreased 0.3% and the areas re‐stimulated; this was repeated three times in each pig. A linear regression analysis using response as dependent and anaesthetic level as independent variable was performed for each stimulus in each pig. Using Student's t‐statistic a 95% confidence interval for the mean slope of each stimulus was constructed. Results No pig responded to eyelash brushing. The mean slopes for the other stimuli indicated increasing responses with decreasing F . Responses to periople pinching and tail and claw clamping showed significant increases. No stimuli consistently increased the magnitude of response in all pigs, and the appearance and absence of a response was inconsistent between pigs. Motor responses occurred in at least one pig during isoflurane burst suppression anaesthesia to all stimuli except eyelash brushing. Conclusions All the stimuli investigated may elicit movement responses during burst suppression anaesthesia with isoflurane except eyelash brushing. No consistent response pattern between pigs was observed with decreasing isoflurane concentration. Of the stimuli evaluated, clamping the tail or claw and pinching the periople appear the most reliable indicators of anaesthetic depth. Clinical relevance The absence or presence of single reflexes does not accurately reflect the degree of isoflurane‐induced cortical depression in individual pigs. 相似文献
65.
消化道疾病往往导致养猪生产中相当大的经济损失,尽管最初的症状只是粪便黏稠不成形.一方面可能是致病性因素改变了猪消化道环境,使机体变得虚弱;另一方面,当育成猪受到腹泻影响时,应该考虑到还有很多可能的原因. 相似文献
66.
Müller C Hamann H Brahm R Grussendorf H Rosenhagen CU Distl O 《Berliner und Münchener tier?rztliche Wochenschrift》2008,121(7-8):286-291
The aims of this study were to analyze the influence of systematic environmental effects on the prevalence of primary non-congenital cataract (CAT), fibreglass cataract in the nucleus (FCN), and prominent suture lines (PSL) and to estimate the heritabilities of these eye diseases in the wild-boar-colored wirehaired Dachshunds (WWD) bred in the German Dachshund Club 1888 e.V. (DTK). Data included 2,430 WWD born between 1995 and 2003 that were examined between 1996 and 2005 by veterinary ophthalmologists. CAT was diagnosed in 3.83% of the 2,430 dogs, FCN in 3.74%, and PSL in 2.76%. Sex, size, inbreeding coefficient, the age of the dog at examination, experience of the veterinary ophthalmologist and the additive genetic effect of the animal were considered in the multivariate linear model. The age of the dog at examination had a significant influence on the prevalence of FCN. The degree of experience of the veterinary ophthalmologist significantly influenced the prevalence of FCN and PSL. Using a transformation into the Dempster-Lerner threshold model, heritability estimates (h(DL)2) for WWD were h(DL)2 = 0.39 +/- 0.13 for CAT, h(DL)2 = 0.36 +/- 0.11 for FCN and h(DL)2 = 0.49 +/- 0.12 for PSL. Positive genetic correlations (r(g)) were found between CAT and FCN (r(g) = 0.58 +/- 0.21), between PSL and FCN (r(g) = 0.83 +/- 0.23), and between CAT and PSL (r(g) = 0.79 +/- 0.06). The eye diseases investigated here in the Dachshund were found to be genetically influenced and positively correlated traits. 相似文献
67.
Between 2002 and 2006, a large number of juvenile northern goshawks (Accipiter gentilis) with central nervous signs were examined. They were aged between 45 and 55 days and had been fed on frozen and thawed day-old chicks. High-performance liquid chromatography showed that the birds had whole blood thiamine levels between 2.2 and 6.0 microg/l; the concentrations of other blood constituents were within their reference ranges. Treatment with thiamine hydrochloride rapidly resolved the clinical signs. Measurements of the concentration of thiamine in 22 free-ranging and captive goshawks showed that they ranged from 45.1 to 200 microg/l. 相似文献
68.
David Johnson Christopher Barrio Frojn Nicholas Bax Piers Dunstan Skipton Woolley Pat Halpin Daniel Dunn Carolina Hazin Maria Dias Tammy Davies Jorge Jimnez Erick Ross Cindy Van Dover Giuseppe Notarbartolo Di Sciara Erich Hoyt Michael J. Tetley Vikki Gunn Henning Von Nordheim 《水产资源保护:海洋与淡水生态系统》2019,29(Z2):162-169
69.
Mervyn Bengston Richard A. H. Davies James M. Desmarchelier Ronald Henning William Murray Bruce W. Simpson Jack T. Snelson Rex Sticka Barry E. Wallbank 《Pest management science》1983,14(4):373-384
Organophosphorothioates and synergised synthetic pyrethroids were used in duplicate field trials carried out on bulk wheat in commercial silos in Queensland and New South Wales. Laboratory bioassays using malathion-resistant strains of insects were carried out on samples of treated grain at intervals over 9 months. These established that all treatments were generally effective. Deltamethrin (2 mg kg?1)+ piperonyl butoxide (8 mg kg?1), fenitrothion (12 mg kg?1)+ fenvalerate (1 mg kg?1)+ piperonyl butoxide (8 mg kg?1), fenitrothion (12 mg kg?1)+ phenothrin (2 mg kg?1)+ piperonyl butoxide (8 mg kg?1) and pirimiphos-methyl (4 mg kg?1)+ permethrin (1 mg kg?1)+ piperonyl butoxide (8 mg kg?1) controlled common field strains of Sitophilus oryzae (L.) and Rhyzopertha dominica (F.). Against a highly resistant strain of S. oryzae, deltamethrin (2 mg kg?1)+ piperonyl butoxide (8 mg kg?1) was superior to the remaining treatments. All treatment combinations completely prevented progeny production in Tribolium castaneum (Herbst), T. confusum Jacquelin du Val and in Ephestia cautella (Walker). Residues of deltamethrin, fenvalerate, permethrin and phenothrin were determined and shown to be highly persistent on stored wheat. During milling, residues accumulated in the bran fractions and were reduced in white flour. They were not significantly reduced during baking. 相似文献
70.
Ungvild Wasteson Anne-Berit Hvaal Henning Srum Egil Myhr Kre Fossum 《Acta veterinaria Scandinavica》1989,30(3):253-257
Yersinia ruckeri produces an antibacterial factor which inhibits the growth of a wide spectrum of Gram-negative and Gram-positive bacteria, though not other strains of Y. ruckeri. The antibacterial factor was produced at low temperatures (4-20 degrees C), but not at 37 degrees C. The activity was lost after treatment of the supernatant with chloroform, UV-light and after boiling of the supernatant. One did not succeed in obtaining the antibacterial factor in a sterile solution. 相似文献