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1.
1. A field experiment was conducted to identify the macroscopic and histological changes associated with the development of foot pad dermatitis (FPD) in growing turkeys. Two affected and two unaffected turkeys were sampled weekly from 1 to 8 and at 10 and 21 weeks of age. 2. At one week old, birds with external signs of FPD (surface skin discolouration) showed abnormal cellular changes of the foot pad integument. As the flock aged the reactions intensified, with one sample exhibiting a fully developed macroscopic lesion at 3 weeks. 3. Major pathological changes had occurred by 6 weeks and all turkeys with external signs of lesions had fully developed microscopic inflammatory cellular lesions. From 6 weeks of age onwards lesions were increasingly numerous and became more overtly necrotic. 4. Externally normal foot pads showed microscopic evidence of lesions after the turkeys reached 4 weeks. 5. We conclude that FPD lesions become severe over a short period of time and at a very early age. 相似文献
2.
Essential thrombocythaemia in an eight-year-old Irish setter is described. The condition is characterised by an autonomous overproduction of thrombocytes in the absence of overt leukaemia. This is believed to be the first recorded case of this condition in the dog. The paper describes the diagnosis and treatment by combination chemotherapy using vincristine, cytosine arabinoside, cyclophosphamide and prednisolone. 相似文献
3.
The occurrence of sleep disorder in three half sibling Lipizzaner is described. Sleepiness, swaying, stumbling, carpal joints buckling and falling down onto the carpal joints had been present since early foal age in all of them. Clinical signs had gradually reduced since the age of 2 years in cases 1 and 3. Sleepiness was induced by going out from the stable in adulthood. A physostigmine test was performed in all three affected horses and produced positive results in cases 1 and 3. The result of the test in case 2 was unclear due to the almost continuous sleepiness of the foal. Hypocretin-1 concentration in the cerebrospinal fluid was established using a standardised radioimmunoassay in case 1 (317.85?pg/mL), case 2 (303.43?pg/mL) and five adult control horses (275.2?±?47.9 [SD] pg/mL) and was considered as normal in all horses. The sire of the affected horses has had 19 other registered offspring who did not show clinical signs of sleep disorder and also dams of all three cases produced healthy foals. Based on the demographic and clinical data together with the responses to the physostigmine challenges, the diagnosis of familial equine narcolepsy was made. 相似文献
4.
Swain JM Pirie RS Hudson NP Else RW Evans H McGorum BC 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(4):613-616
The case was examined at the Easter Bush Veterinary Hospital, The University of Edinburgh. A 520 kg, 6-year-old Thoroughbred gelding was referred for evaluation of acute onset profound depression, head pressing, and lack of response to external stimuli. The horse had a history of moderate weight loss over several months despite adequate nutrition and a good appetite. Previous episodes of weakness had been observed following administration of anthelmintics, namely, alternate doses of pyrantel and ivermectin, administered every 8 weeks. In an attempt to eliminate a possible parasitic cause of weight loss, over the 7 days prior to presentation, the referring veterinary surgeon treated the horse with a 5-day course of fenbendazolea (7.5 mg/kg PO q24h) and moxidectinb (0.4 mg/kg PO), 2 days later. A 5-day course of prednisolonec (1 mg/kg PO q24h) was initiated on the same day as the fenbendazole. This dose was then tapered to 0.5 mg/kg PO q24h, and was still being administered at the time of presentation. 相似文献
5.
6.
Sánchez-Cordón PJ Hervás J Chacón de Lara F Jahn J Salguero FJ Gómez-Villamandos JC 《Avian diseases》2002,46(2):485-492
In this paper we report on an outbreak of reovirus, herpesvirus (Pacheco disease), and/or mycosis infection (Aspergillus spp. and Zygomyces spp.) affecting a batch of young African grey parrots (Psittacus erithacus), with 80% morbidity and 30% mortality. Study material was taken from five birds (four dead and one euthanatized) with a range of clinical symptoms (depression, diarrhea, respiratory symptoms). Diagnosis was confirmed by immunohistochemical detection of avian reovirus, electron microscopy, and virus isolation. Viral antigen of reovirus was detected mainly in large mononuclear cells in the bursa of Fabricius and the spleen, pancreas epithelial cells, and circulating cells; lymphoid organs displayed the largest number of immunopositive cells and severe lymphocyte depletion. Bacteriologic study was negative. Reovirus infection was common in all birds studied, whereas Pacheco disease and mycosis were found in only some, suggesting that reovirus could be the initial cause triggering the outbreak and facilitating infection by other agents and their swift spread through the batch. 相似文献
7.
The aim of the study was to investigate source‐sink relations of wheat under continuous heat stress and to identify bottle necks of yield formation. A pot experiment was conducted in two climatic chambers exposing wheat plants (Triticum aestivum L. cv. Thasos) either to day/night temperatures of 20/20°C (control conditions) or of 30/25°C (heat stress) during the whole vegetation period in the absence of plant water deficit. Plants were harvested at four phenological stages: three‐node stage (DC 33), start of flowering (DC 61), grain filling (DC 75) and maturity (DC 94). Heat stress shortened the development phases of the plants and caused a significant decrease in total above‐ground biomass between 19% and 41%. At grain filling and at maturity, the reductions in total shoot biomass mainly resulted from grain yield depressions by 77% and 58%, respectively. The ear number per plant was significantly higher under heat stress in comparison with the control, at maturity it was more than doubled. On the contrary, under heat stress, the kernel number per ear was strongly decreased by 83% and 75% during grain filling and at maturity, respectively. The decrease in individual kernel weight was 23% at maturity. Thus, the heat‐stressed plants were able to strongly increase the number of ear‐bearing tillers which were able to set only a small number of kernels, yet these kernels showed good grain filling. The harvest index (HI) of heat‐stressed plants was significantly reduced by 36% (control: HI = 50.1% ± 0.4, heat: HI = 32.2% ± 0.9***). The plants in the stress treatment adapted to the adverse conditions by less biomass production which presumably allowed a higher transpiration without an increase in total water consumption. Nevertheless, under heat stress, the water use efficiency (WUEgrain) was strongly decreased by 62% as a result of a small grain yield. In ears and grains, the sucrose, glucose and fructose concentrations were not significantly different between control and heat stress at start of flowering and during grain filling. Thus, the supply of assimilates was not restricted (no source limitation). Sink capacity was reduced by heat stress, as lesser and smaller kernels were produced than in the control. Concerning sink activity, the sink‐limiting step during kernel set is probably the active transport of hexoses across the plasma membrane into the developing kernels, which could also affect grain filling. This needs to be investigated in more detail in further studies. 相似文献
8.
We tested whether a ‘Lockerbraunerde’ from the heights of the Zittauer Gebirge in Eastern Saxony exhibited andic properties and classified it according to the rules of the World Reference Base for Soil Resources (WRB, 1998). To achieve this, we characterized a selected soil by means of routine soil analysis; selective dissolution procedures; X‐ray diffraction (XRD); X‐ray fluorescence (XRF), and Transmission Electron Microscopy (TEM). We used field criteria (Thixotropy; NaF‐field test) to obtain a map of the spatial distribution of soils with potential andic properties. We found that the soil fulfilled all requirements to be classified as an Andosol. The composition of the colloidal phases was exactly intermediate between sil‐andic and alu‐andic. At the same time, the soil had a spodic horizon [determined through the depth function of the Alo+½Feo criterion]. As there was no indication of vertical translocation of metal‐organic complexes, but sufficient evidence to suggest the downward movement of mobile Al/Si‐phases, we maintain to classify the soil as an Endoskeleti‐Umbric Andosol and propose the existence of a pedogenetic pathway intermediate between Podsolisation and Andosolization. We conclude that the spodic horizon in the WRB is not well defined because of the dominance of the Alo+½Feo criterion over morphological evidence. We further suggest the German soil taxonomy to be modified to better represent soils containing short range order minerals. 相似文献
9.
Prof. Dr. Else Jahn 《Journal of pest science》1986,59(1):8-14
First-zones of earth radiations are shown as preferred places of aggregations of insects, especially forest insects. After a survey given about factors, probably evoking dowsing, many examples are given for influences of electric-magnetic powers and such of gravity phenomens to behaviour and vital functions of insects, particularly mentioning the results of research ofG. Becker andF. Schneider. Considering facts in literature together with own experiences in this field of investigation the opinion is expressed, that both ultraoptic factors-both of efficiency on insects: a) the electric-magnetic powers-different from their environment and b) the metal effect as a gravity phenomen are necessary for the appearance of the dowsing phenomen. The metal effect is capable to stimulate the movement of the rod, but needs for its releasing from coverings the presence of altered electric-magnetic fields. The metal effect may likely be compared to resonance oscillations of gravity waves arising on Aluminium plates, as it is supposed bySchneider. 相似文献
10.
Ohne Zusammenfassung 相似文献