A method for estimating fish density through the catches of gillnets     

Feodor Lobyrev  Matthew J. Hoffman 《Fisheries Management and Ecology》2023,30(1):24-35

We propose a new method for estimating fish density using catches obtained by gillnets of given mesh size. This method builds on work for estimating the number of fish approaching a gillnet by modelling the fish movement that leads to a gillnet encounter. The theoretical framework is developed, and the method is tested on catch data for cod Gadus morhua and Dolly Varden Salvelinus malma to demonstrate how the method can be applied. The method relies on knowledge of geometric properties of the net, and morphological and behavioural properties of the fish, so we explore the sensitivity of the estimates to some of these parameters. Estimates are most sensitive to the morphological parameter of the angle the mouth is open while swimming and largely invariant to estimates of uncertain parameters like maximum number of fish that can be caught by the particular net.  相似文献   

Flood plain staggers, a tunicaminyluracil toxicosis of cattle in northern New South Wales     

CA BOURKE  MJ CARRIGAN  SCJ LOVE 《Australian veterinary journal》1992,69(9):228-229

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EFFECTS OF EXPERIMENTAL NERVE ROOT COMPRESSION ON ARTERIAL BLOOD FLOW VELOCITY IN THE SEVENTH LUMBAR SPINAL GANGLION OF THE DOG: MEASUREMENT USING INTRAOPERATIVE DOPPLER ULTRASONOGRAPHY     

Jeryl C.  Jones  DVM  PHD  Judith A.  Hudson  DVM  PhD  Donald C.  Sorjonen  DVM  MS  Charles E.  Hoffman  CVT  BS  LATG  Kyle G.  Braund  BVS  MVS  PhD  James C.  Wright  DVM  MS  PhD  Phillip D.  Garrett  DVM  MS  Jan E.  Bartels  DVM  MS 《Veterinary radiology & ultrasound》1996,37(2):133-140

Intraoperative Doppler ultrasonography was used to measure the effects of four experimental nerve root compression treatments (central compression, central-plus-lateral compression, lateral compression, and compression release) on arterial blood flow velocities in the seventh lumbar spinal ganglion of three dogs. Graphed blood flow velocity changes (change = treatment value − pretreatment value) were below baseline during the first three compression treatments and above baseline following compression release. Mean blood flow velocity changes for both central-plus-lateral compression and lateral compression differed (p ≤ 0.05) from changes for central compression. Changes for central-plus-lateral compression did not differ (p > 0.05) from changes for lateral compression. Changes among the first three compression treatments differed (p ≤ 0.05) from changes for compression release. No histologic abnormalities were identified in compressed nerve tissues, compared to contralateral controls. These findings indicate that stenosis within the L7-S1 intervertebral foramen may cause ischemia of the L7 spinal ganglion in dogs.  相似文献   

Experimental evidence that tryptamine alkaloids do not cause Phalaris aquatica sudden death syndrome in sheep     

CA BOURKE  MJ CARRIGAN  RJ DIXON† 《Australian veterinary journal》1988,65(7):218-220

The acute toxicity for sheep of 3 alkaloids that occur in Phalaris acquatica was examined by intravenous and oral administration. The lowest tested dose rates that produced clinically observed signs were, for 5-methoxy dimethyltryptamine, 0.1 mg/kg body weight intravenously and 40 mg/kg orally; for gramine, 10 mg/kg intravenously and 500 mg/kg orally; and for hordenine, 20 mg/kg intravenously and 800 mg/kg orally. All induced the clinical signs observed in the nervous form of phalaris toxicity, but none induced the cardiac, sudden death, syndrome.  相似文献   

Chronic locomotor dysfunction, associated with a thalamic-cerebellar neuropathy, in Australian Merino sheep     

CA BOURKE  MJ CARRIGAN  CHR DENT 《Australian veterinary journal》1993,70(6):232-233

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Lack of toxicity of Ailanthus altissima (tree-of-heaven) for goats     

CA BOURKE 《Australian veterinary journal》1996,74(6):465-465

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Factors affecting in-transit shrink and liver abscesses in fed steers     

B R Harman  M H Brinkman  M P Hoffman  H L Self 《Journal of animal science》1989,67(2):311-317

Live weight loss (shrink) and liver conditions (abscesses) were determined on 3,570 crossbred steers of predominantly British breeding over a 5-yr period. Starting in November 1979, steers were placed on feed at bimonthly intervals and provided one of three housing treatments: no shelter, access to overhead shelter or confinement. All steers were implanted with Synovex during the first 3 yr and Compudose the last 2 yr and fed a diet consisting of high-moisture corn grain, which provided 85% of the energy, and corn silage, along with a protein, vitamin and mineral supplement. Cattle were processed into beef after a feeding period of approximately 160 d. Year affected shrink (P less than .001), and month on feed and housing type tended to alter shrink. Cattle marketed during summer and fall and those outside without overhead shelter tended to shrink more. Year, month on feed and housing type affected liver condition (P less than .01). Cattle started on feed in November and January and cattle housed in confinement or outside without overhead shelter had higher incidences of liver abscesses and slower average daily gains (P less than .01). Daily gains for steers with normal and abnormal livers were not different (P greater than .19) for any month started on feed or housing treatment. These results indicate that under the conditions of this study a 2 or 3% weight loss should be expected during the marketing of finished steers and a 16% incidence of liver abscesses should be anticipated, with some modification of the latter due to time of year and housing. The presence of liver abscesses at the time of processing steers into beef did not reduce feedlot performance.  相似文献   

THE MECHANISM OF ENHANCEMENT OF INFECTIONS BY TESTICLE EXTRACT     

Hoffman DC  Duran-Reynals F 《Science (New York, N.Y.)》1930,72(1872):508

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Preliminary study of the pharmacokinetics and toxicopathy of deoxynivalenol (vomitoxin) in swine     

R W Coppock  S P Swanson  H B Gelberg  G D Koritz  W E Hoffman  W B Buck  R F Vesonder 《American journal of veterinary research》1985,46(1):169-174

Study was made of the pharmacokinetics and toxicopathy of deoxynivalenol (DON, vomitoxin) given IV to swine. In the 24 hours after swine were given DON, clinical signs of vomiting, diarrhea, muscular weakness, tremors, and twilight coma were similar to those observed with other 12,13-epoxytrichothecenes. Hypoglycemia and pancreatic islet cell lesions were observed which indicated that DON-induced changes in intermediary metabolism may be an insidious aspect of DON intoxication. Histopathologic examination of all organ systems revealed pancreatic acinar and islet cell necrosis and mild lympholysis of the mesenteric lymph nodes. The renal excretion of DON was altered by IV infusion of saline solution. Pharmacokinetic findings may indicate that DON was both secreted and reabsorbed by the renal tubules. The half-life of DON ranged from 2.08 to 3.65 hours. Residues of DON were not found in skeletal muscle of swine at 24 hours after dosing.  相似文献   

A percutaneous transtracheal catheter system for improved oxygenation in foals with respiratory distress.     

A M Hoffman  L Viel 《Equine veterinary journal》1992,24(3):239-241

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