Bluetongue virus serotypes 1 and 3 infection in Poll Dorset sheep   总被引：1，自引：0，他引：1  

C. HAMBLIN  JS SALT  SD GRAHAM  K. HOPWOOD  AM WADE-EVANS 《Australian veterinary journal》1998,76(9):622-629

Objective To study the clinical signs following bluetongue virus serotypes 1 and 3 infection in Poll Dorset sheep.
Design A clinical and pathological study.
Procedure Twenty Poll Dorset sheep were inoculated with bluetongue virus serotypes 1 or 3, each inoculum having a different passage history. The sheep were examined daily and their clinical appearance and rectal temperatures recorded. Heparinised and non-heparinised blood samples were taken at intervals for virological and serological study. Gross pathological findings were recorded for several sheep at necropsy and tissue samples were collected from three sheep for virological studies.
Results All inoculated sheep developed clinical disease. The clinical signs and gross pathological changes varied considerably but were consistent with damage to the vascular endothelial system. There was a decline in the titres of infectious bluetongue virus and of antigen in tissues collected between 7 and 12 days after infection.
Conclusions The severity of disease was related to the speed of onset and duration of pyrexia and not the development or titre of viraemia. Generally, those animals with sensitive mouths, depression, coronitis, recumbency and reluctance to move were the most debilitated. Whole blood was the most reliable source of infectious virus from acutely and chronically infected and convalescent animals. However, tissue samples particularly spleen, collected from dead or killed animals suffering from either peracute or acute forms of disease were most appropriate for the rapid confirmation of a clinical diagnosis.  相似文献   

Forestry and Land Use near Aberdeen in North-east Scotland     

TULEY  GRAHAM 《Forestry》1987,60(1):135-151

The forests near Aberdeen are described. There has been a gradualincrease in the area covered by trees in the last 40 years butthe rate of change has been slower than in the est of Scotland.The amount of Sitka spruce plantation has increased but Scotspine is still the dominant conifer. Extensive natural birchwoodland exist although most of it is unmanaged. There are nolarge timber using industries near Aberdeen and most timberis processed outside Grampian Region.  相似文献   

Physical and biological consequences of a climate event in the central North Pacific   总被引：4，自引：0，他引：4  

JEFFREY J. POLOVINA  GARY T. MITCHUM  NICK E. GRAHAM  MITCHELL P. CRAIG  EDWARD E. DEMARTINI  ELIZABETH N. FLINT 《Fisheries Oceanography》1994,3(1):15-21

Climatic changes over the North Pacific which began in the mid 1970s, peaked in the early 1980s, and ended by the late 1980s, appear to have altered productivity at various trophic levels in the marine ecosystem in the central North Pacific. The climatic change resulted in increased mixed layer depth and the frequency of deep mixing events, particularly during January-March. A number of biological time series for species ranging from primary to apex levels in the North-western Hawaiian Islands, show corresponding declines in productivity of 30–50% from the early 1980s to the present. We hypothesize that during the early 1980s, increased mixing due to the climate event resulted in greater nutrient input into the euphotic zone and ultimately increased ecosystem productivity. Productivity over a range of trophic levels declined when the climate event ended.  相似文献   

Strength in diversity: fish sanctuaries and deep-water pools in Lao PDR     

I. G. BAIRD 《Fisheries Management and Ecology》2006,13(1):1-8

Abstract  Fish sanctuaries are types of aquatic protected areas common throughout the landlocked country of Lao PDR. The key to their successful implementation in Laos appears to be local support. Therefore, they fit well within the context of community-based fisheries/co-management programmes. Fish sanctuaries are almost always established in deep-water pools, which serve as important dry season refuges for fish. The best-known fish sanctuaries in Laos are known as Fish Conservation Zones (FCZs), and are found in the mainstream Mekong River in Khong district, Champasak province, southern Laos. In Khong, there is increasing evidence that FCZs established by villagers, but with government support, are important places of concentration for various fish species. FCZs can benefit fish stocks, especially relatively sedentary species, but also highly migratory ones. FCZs are not panaceas for solving all the fisheries problems in Laos or the Mekong River Basin, but they represent important management tools that should not be overlooked.  相似文献   

Aeromonas hydrophila B-haemolysin: purification and examination of its role in virulence in 0-group channel catfish, Ictalurus punctatus (Rafinesque)     

R. L. THUNE  MAUREEN C. JOHNSON  T. E. GRAHAM  R. L. AMBORSKI 《Journal of fish diseases》1986,9(1):55-61

Abstract. A single step procedure for purification of B-haemolysin from Aeromonas hydrophila is described which recovered 94% of the haemolytic activity with a sixfold increase in specific activity. Toxicity of haemolysin in 0-group channel catfish was 0–6 mg of purified protein per gram offish. Of six strains of A. hydrophila evaluated for differential toxin production and virulence in 0-group channel catfish, three B-haemolysin-deficient strains were virulent while three B-haemolysin-producing strains were avirulent.  相似文献   

Effects of Carbon Dioxide Insufflation Combined With Changes in Body Position on Blood Gas and Acid-Base Status in Anesthetized Llamas (Llama glama)     

HUI-CHU LIN DVM  MS  Diplomate ACVA    AUBREY N. BAIRD DVM  MS  Diplomate ACVS    DAVID G. PUGH DVM  MS  Diplomate ACT    DAVID E. ANDERSON DVM  MS  Diplomate ACVS  EARL M. GAUGHAN DVM  MS  Diplomate ACVS 《Veterinary surgery : VS》1997,26(5):444-450

Objective— To study the combined effects of intra-abdominal CO₂ insufflation with changes in body position during laparoscopy in xylazine-ketamine-halothane anesthetized llamas. Study Design— Prospective, controlled study. Animals— Nine castrated, male llamas weighing 114 ± 23 kg, 3 to 13 years old. Methods— Three llamas (preliminary study [PS] group) were used to study the effect of right lateral, dorsal, and left lateral recumbency on gas exchange and acid-base status. The other six (experimental study [ES] group) were used to study the combined effects of changes in body position and CO₂ insufflation to an intraabdominal pressure of 10 to 12 mm Hg. Heart rate, respiratory rate, and indirect arterial blood pressures (systolic [SAP], mean [MAP], and diastolic [DAP]) were recorded every 5 minutes during anesthesia. Arterial blood gases (PaO₂ and PaCO₂) and acid-base status (pHa and HCO₃) were measured immediately after induction of anesthesia and before each change of position. Results— In the PS group, significant decreases in SAP, MAP and PaCO₂ and increases in PaO₂ and pHa were observed when the llamas were turned from right lateral to dorsal recumbency. Values for HCO_-3 were lower than the postinduction values, but they remained unaffected by the changes in position. In the ES group, values for MAP were significantly lower when the llamas were placed in dorsal and left lateral recumbency than those observed during right lateral recumbency. Arterial O₂ tension during right lateral recumbency was lower but returned to preinsufflation values when the llamas were placed in the dorsal position. All llamas recovered uneventfully within 30 minutes after termination of anesthesia. Conclusions— Insufflation of CO₂ and changing body position induce minor and transient changes in cardiovascular and respiratory function. Clinical Relevance— Laparoscopy with mild intra-abdominal CO₂ insufflation (10 to 12 mm Hg) can be used safely in spontaneously breathing llamas anesthetized with xylazine, ketamine, and halothane.  相似文献   

Systemic candidiasis in a Suffolk ram     

TF JUBB  JD BAIRD  DH PERCY 《Australian veterinary journal》1988,65(10):333-335

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The distribution and importance of cabbage stem flea beetle (Psylliodes chrysocephala (L.)) on winter oilseed rape in England     

C. W. GRAHAM  D. V. ALFORD 《Plant pathology》1981,30(3):141-145

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Phenothiazine treatment of yearling beeves on winter pastures     

VEGORS HH  SMITH WN  BAIRD DM  CIORDIA H  BIZZELL WE  SELL OE 《American journal of veterinary research》1958,19(73):805-810

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Redistribution of Vertical Ground Reaction Force in Dogs With Experimentally Induced Chronic Hindlimb Lameness     

PAUL F. RUMPH DVM  MS    STEVEN A. KINCAID DVM  PhD    DENISE M. VISCO PhD    DEBRA K. BAIRD DVM    JOHN R. KAMMERMANN MS  MARK S. WEST PhD 《Veterinary surgery : VS》1995,24(5):384-389

When lameness occurs in a load-bearing limb, compensatory load adjustments are made in the other supporting limbs. The vertical component of the ground reaction force, as measured by force platform analysis, reflects these adjustments. This study describes the pattern of vertical ground reaction force redistribution during experimental, chronic hindlimb lameness in dogs. The peak and impulse of the vertical ground reaction force were measured and described in 13 dogs before, and at 2, 6, and 12 weeks after transection of the cranial cruciate ligament. These variables were compared among limbs. The vertical ground reaction force in the forelimbs did not change significantly during the course of the study. At 2, 6, and 12 weeks after surgery, means of peak vertical force in the limb that underwent surgery were 18.9%, 44.0%, and 61.3% respectively, of presurgical values. In the contralateral limb, corresponding values were 131.7%, 112.8% and 112.9% respectively. If one accepts the relationship of mechanical loading to musculoskeletal architecture and the now certain relationship between lameness and compensatory loading of other limbs, then the use of another limb of the same animal as a control is a potential study design flaw.  相似文献