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Disease of geese caused by a new herpesvirus 总被引:3,自引:0,他引:3
PJ KETTERER BJ RODWELL HA WESTBURY† PT HOOPER† AR MACKENZIE‡ JG DINGLE§ HC PRIOR 《Australian veterinary journal》1990,67(12):446-448
A goose flock farmed outdoors in south-eastern Queensland suffered an outbreak of peracute disease with high death rate (97%). Small button ulcers and large plaques overlying lymphocyte aggregates were present on the mucosa of the small intestine of affected birds. Small white foci of necrosis and focal haemorrhages were seen in the livers. Numerous intranuclear inclusion bodies were observed microscopically in hepatocytes and a herpesvirus which grew rapidly in chicken kidney cells was isolated from tissues. Duck virus enteritis (DVE) was suspected but DVE antiserums failed to neutralise the virus. Further serological studies with a limited range of known avian herpesviruses have failed to identify the virus. Experimental transmission resulted in high mortality in geese (100%), lower mortality in ducklings and nil mortality in chickens. Surveillance studies showed no evidence of infection in domestic and wild birds beyond the original farm and the infection appears not to have been established in the area. Wild ducks, which were frequent visitors to the farm dam, were considered the most likely source of the infection. 相似文献
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甘蓝型油菜(Brassica napus)无花瓣突变体“ Ap-Tengbe ”花瓣性状的遗传规律 总被引:2,自引:0,他引:2
本项研究旨在探明甘蓝型油菜突变体Ap-Tengbe无花瓣性状的遗传规律,‘Ap-Tengbe’和德国栽培品种‘Falcon’之间通过正反交产生两个方向的F1,BC1-1(F1和‘Ap-Tengebe’之间),BC1-2(F1和‘Falcon’之间)以及F2各遗传群体,根据田间各遗传群体PDgr(花瓣度)的观察和统计,作者提出‘Ap-Tenge’突变体无花瓣性状的遗传由细胞质和两对核隐性基因共同控制 相似文献
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S Schäfer‐Somi S Sabitzer D Klein E Reinbacher H Kanca HB Beceriklisoy OA Aksoy I Kucukaslan HC Macun S Aslan 《Reproduction in domestic animals》2013,48(1):20-26
The aim of this study was to investigate the course of expression of platelet‐activating factor (PAF), PAF‐receptor (PAF‐R), epidermal growth factor (EGF), EGF‐R, vascular endothelial growth factor (VEGF), VEGF‐R1 and VEGF‐R2 in uterine tissue during canine pregnancy. For this purpose, 20 bitches were ovariohysterectomized at days 10–12 (n = 10), 18–25 (n = 5) and 28–45 (n = 5) days after mating, respectively. The pre‐implantation group was proven pregnant by embryo flushing of the uterus after the operation, the others by sonography. Five embryo negative, that is, non‐pregnant, bitches in diestrus (day 10–12) served as controls. Tissue samples from the uterus (placentation sites and horn width, respectively) were excised and snap‐frozen in liquid nitrogen after embedding in Tissue Tec®. Extraction of mRNA for RT‐PCR was performed with Tri‐Reagent. In the embryos, mRNA from all factors except VEGF was detected. In the course of pregnancy, significantly higher expression of PAF and PAFR as well as VEGF and VEGFR2 during the pre‐implantation stage than in all other stages and a strong upregulation of EGF during implantation were characteristic. The course of EGF was in diametrical opposition to the course of the receptor. These results point towards an increased demand for VEGF, EGF and PAF during the earliest stages of canine pregnancy. 相似文献
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Organic farming (OF) has significantly increased in importance in recent decades. Disease management in OF is largely based on the maintenance of biological diversity and soil health by balanced crop rotations, including nitrogen‐fixing and cover crops, intercrops, additions of manure and compost and reductions in soil tillage. Most soil‐borne diseases are naturally suppressed, while foliar diseases can sometimes be problematic. Only when a severe disease outbreak is expected are pesticides used that are approved for OF. A detailed overview is given of cultural and biological control measures. Attention is also given to regulated pesticides. We conclude that a systems approach to disease management is required, and that interdisciplinary research is needed to solve lingering disease problems, especially for OF in the tropics. Some of the organic regulations are in need of revision in close collaboration with various stakeholders. © 2015 Society of Chemical Industry 相似文献
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HC LIN SS WALLACE JW TYLER† RL ROBBINS JC THURMON‡ DF WOLFE 《Australian veterinary journal》1994,71(8):239-242
Summary The anaesthetic effects of intravenous tiletamine-zolazepam 6.6 mg/kg-ketamine 6.6 mg/kg (TK) and tiletamine-zolazepam 6.6 mg/kg-ketamine 6.6 mg/kg-xylazine 0.11 mg/kg (TKX) were evaluated in six wethers. Heart rate, respiration rate, arterial blood pressure, and the electrocardiogram were monitored during anaesthesia. Analgesia was tested by electrical stimulation in the left flank. Atropine (0.03 mg/kg) was given intramuscularly before induction, but after recording of baseline heart rate and respiratory rate. The duration of analgesia was 28.7 ± 6.9 min with TK and 82.8 ± 26.6 min with TKX. Heart rate increased significantly within 5 min after TK or TKX administration. Respiratory rate remained unchanged after TK administration, but increased significantly from 5 to 45 min after TKX administration. Arterial blood pressure decreased significantly at 15 min with TK and 30 min with TKX. Sheep remained recumbent for 201 min with TK and 166 min with TKX. All recovered uneventfully. We conclude that either TK or TKX may be used for anaesthetising sheep. 相似文献
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Arid and semiarid lands occupy about one-third of the Earth's land surface. Interpretation of soil formation and geomorphic features of arid lands is needed to assess their soil ecological potentials, limitations, problems and management needs. The objective of this paper was to study the geomorphic features and soil formation of the arid lands in northeastern Jordan, to provide information that could be used by land managers in the study area and other arid land areas. Five representative soil pedons were excavated and described in the field. Soil samples from each horizon per pedon were taken to the laboratory for chemical and physical analyses. Geomorphic features of the area were also studied. Most of studied land surfaces are plains where eolian deflation has exposed loose gravels consisting predominantly of pebbles forming desert pavements. Desert pavements cover most of the land surface, excluding the mud playas, and are composed of basalt clasts. The accumulation of calcium carbonate and gypsum within these soils create problems for their agricultural development. Accumulation of eolian fine-grained silt has resulted in the formation of a vesicular horizon. The climatic variations during the late quaternary and the late Holocene periods contributed to the development of the desert pavement and the vesicular horizons. Clay illuviation and argillic horizon development within these soils is assumed to be a relict feature from more humid climates during the Quaternary. Sustainable agricultural development of such arid lands may not be easy. In general, these soils have high erodibility, high runoff generation potential, high susceptibility to seal and crust formation, poor water-holding capacity, pedon hardening and structural instability. 相似文献