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1.
Sedative and cardiovascular effects of romifidine, alone and in combination with butorphanol, in the horse 总被引:1,自引:1,他引:0
The behavioural and sedative effects of intravenous (iv) romifidine (40 and 80 μg/kg bodyweight [bwt]) alone or in combination with iv butorphanol (50 μg/kg bwt) were investigated in four ponies and one Thoroughbred horse. Apparent sedation, as judged by the lowering of the head, and by the response to imposed touch, visual and sound stimuli was assessed. The combination with butorphanol reduced the animals' response to imposed stimuli when compared with the effect of the same dose of romifidine alone. Following the administration of romifidine/butorphanol combinations muzzle tremor was noted and some animals attempted to walk forward. In a separate series, the cardiopulmonary effects of iv romifidine (80 μg/kg bwt) alone, or in combination with butorphanol (50 μg/kg bwt) were investigated. Romifidine and the romifidine/butorphanol combination caused similar cardiovascular changes, these being bradycardia with heart block, and hypertension followed by hypotension. Romifidine caused a transient decrease in arterial oxygen tensions and arterial carbon dioxide tensions had increased significantly by the end of the 90 min recording period. Romifidine/butorphanol combinations produced significantly higher arterial carbon dioxide tensions during the first 15 mins after drug administration than did romifidine alone. Butorphanol at 50 μg/kg bwt iv reduced the response to imposed stimuli in horses sedated with romifidine. The combination produced no cardiovascular changes beyond those induced by romifidine alone, but did increase the degree of respiratory depression. 相似文献
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Abstract Sir, - Andrews'((2)) checklist of helminth parasites of wild ruminants in New Zealand recorded the presence of 10 species of gastrointestinal nematodes in chamois (Rupicapra rupicapra rupicapra L.) from "Central South Island". In October 1978 we examined 28 freshly-shot chamois cadavers from the Harper-Avoca watershed in the headwaters of the Rakaia River. Six of the nematode species reported by Andrews were found again; viz. Ostertagia ostertagi, O. circumcincta, O. trifurcata, Nematodirus filicollis, Oesophagostomum venulosum and Trichuris ovis. The 4 species found by Andrews that were not recovered by us from the animals we examined were: Trichostrongylus axei, T. vitrinus, Spiculotragia spiculoptera and S. asymmetrica. On the other hand we found 4 helminths not encountered by Andrews: 3 nematodes: Nematodirus spathiger (Railliet, 1896), N. abnormalis (May, 1920), and Chabertia ovina (Fabricius, 1794), and 7 specimens of the cestode Moniezia expansa (Rud., 1805). Nematodirus spathiger was the most commonly encountered Nematodirus species, but generally the numbers of all 3 species encountered were low as might be expected in a sample of adult and almost year-old animals. It is probable that most of the adults had acquired some measure of immunity((3)), and the most susceptible group, the kids, would not be born until late November. Because peptic digestion was not used to recover juveniles from the intestinal submucosa, only small numbers of adults were obtained. 相似文献
4.
Dose response of weeds to methyl iodide and methyl bromide 总被引:1,自引:0,他引:1
W. M. ZHANG M. E. McGIFFEN JR J. O. BECKER H. D. OHR J. J. SIMS R. L. KALLENBACH 《Weed Research》1997,37(3):181-189
Labonuory bioassay and field experiments were conducted to characterize the dose response of weeds to methyl iodide and methyl bromide as soil fumigants. The patterns in potency of both fumigants and in sensitivity of diffcretit weed species to the fumigants were distinguished with the use of logistic dose-response models. Similar to its response to methyl hromide fumigation. Amaranthus retrofleus L. was the most sensitive to methyl iodide fumigation. Cyperus rotundtis L. was the least sensitive to methyl iodide fumigation, whereas Portuloca oleracea L. was the least sensitive to methyl hromide. Lolium multiflorum Lam. Abutilon theophrasti Medik. Chenopodium album L. P. ateracea . Brassica kaber (D.C.) L.C. Wheeler and Cyperus escuden-tus L. were similar in sensitivity to methyl iodide. Methyl iodide was as potent as methyl bromide for A. retroflexus but more potent than methyl bromide for L. multiflorum , A. theophrasti. C. album. P. oleracea. B. kaber, C. esculentus and C. rotundus. The dose response for weeds in the field was similar to that obtained in laboratory bioassays. Under fieid conditions. 280 kg ha-1 methyl iodide killed all species tested except Solanum nigrum L Methyl iodide appears to be a suitable replacement for meihyl bromide because it can be used in situations simitar to methyl bromide fumigation, has superior efficacy against a broad spectrum of pests and has a low potential for degrading the earth's ozone lavers. 相似文献
5.
D. L. Clarke 《The Journal of small animal practice》2018,59(6):324-333
Feline ureteral obstructions are an increasingly recognised and challenging diagnostic and management problem. Many cats with ureteral obstructions are critically ill at the time of diagnosis, especially if there is dysfunction of the contralateral kidney. They may present with varying severities of acute kidney injury, electrolyte disturbances, and may have comorbidities such as heart disease that complicate perioperative and long‐term management. Medical management, which may consist of rehydration and restoration of intravascular volume with intravenous fluid therapy, osmotic diuresis, ureteral muscle relaxation, and antimicrobials for infection, is important in feline ureteral obstruction patients. Despite medical management, many cats with ureteral obstructions will require decompression of the obstructed kidney to relieve pressure‐nephropathy and restore urine flow. However, some cats may be too unstable for traditional medical management and require more emergent intervention to relieve the obstruction and address the life‐threatening sequelae to acute kidney injury, such as hyperkalaemia and fluid overload. Both surgical and interventional methods to address ureteral obstructions have been described in veterinary medicine, though debate continues as to the ideal approach. 相似文献
6.
G. C. BLASIOLA JR 《Journal of fish diseases》1979,2(6):493-500
Abstract. A new species of Microsporida, Glugea heraldi , is described from the seahorse Hippocampus erectus . Measurements of fixed spores and notes on the histopathology of parasitized tissue are given. 相似文献
7.
American Journal of Potato Research - 相似文献
8.
Anatomical and physiological basis for the allometric scaling of cisplatin clearance in dogs 下载免费PDF全文
S. Achanta A. Sewell J. W. Ritchey K. Broaddus D. W. A. Bourne C. R. Clarke L. K. Maxwell 《Journal of veterinary pharmacology and therapeutics》2016,39(3):224-236
Cisplatin is a platinum‐containing cytotoxic drug indicated for the treatment of solid tumors in veterinary and human patients. Several of the algorithms used to standardize the doses of cytotoxic drugs utilize allometry, or the nonproportional relationships between anatomical and physiological variables, but the underlying basis for these relationships is poorly understood. The objective of this proof of concept study was to determine whether allometric equations explain the relationships between body weight, kidney weight, renal physiology, and clearance of a model, renally cleared anticancer agent in dogs. Postmortem body, kidney, and heart weights were collected from 364 dogs (127 juveniles and 237 adults, including 51 dogs ≥ 8 years of age). Renal physiological and cisplatin pharmacokinetic studies were conducted in ten intact male dogs including two juvenile and eight adult dogs (4–55 kg). Glomerular filtration rate (GFR), effective renal plasma flow, effective renal blood flow, renal cisplatin clearance, and total cisplatin clearance were allometrically related to body weight with powers of 0.75, 0.59, 0.61, 0.71, and 0.70, respectively. The similar values of these diverse mass exponents suggest a common underlying basis for the allometry of kidney size, renal physiology, and renal drug handling. 相似文献
9.
Johansson AM Gardner SY Atkins CE LaFevers DH Breuhaus BA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(2):302-307
BACKGROUND: Recurrent airway obstruction (RAO) is common in horses. Although pulmonary artery (PA) pressure increases during RAO, cardiac function in horses with RAO has received limited attention. HYPOTHESIS: The purpose of this study was to noninvasively determine the cardiovascular effects of acute pulmonary obstruction (APO) in horses with RAO and their reversibility. ANIMALS: Five geldings with RAO, inducible by exposure to moldy hay, were studied. METHODS: Pulmonary mechanics, echocardiography, serum troponin I concentrations, arterial blood gases, and hematocrit were obtained before and after 7 days of APO. Heart rate, PA diameter and flow characteristics, right and left ventricular luminal dimensions and wall thicknesses, global cardiac performance, and evidence of myocardial damage were evaluated. Pulmonary mechanics and echocardiography were reevaluated during remission. RRESULTS: Severe, transient APO did not induce chronic cor pulmonale in horses, because cardiac anatomy and function were normal between episodes. An acute episode of APO produced anatomical and functional cardiac changes in both the right and left heart (including increased PA diameter, abnormal septal motion, and decreased left ventricular diameter and estimated stroke volume), possibly because of the development of pulmonary hypertension, without apparent myocardial damage. The decrease in stroke volume was offset by the increase in heart rate. CONCLUSIONS AND CLINICAL IMPORTANCE: With APO of 7 days' duration, cardiovascular abnormalities and the functional airway changes that produce them are reversible when the offending allergens are removed. 相似文献
10.
A 4-month old, 200 kg, grey warmblood colt presented for a firm, non painful mass on the distal medial aspect of the left third metatarsus. Excisional biopsy revealed a diagnosis of haemangiosarcoma. Equine haemangiosarcoma is uncommon and only limited reports of successful treatment are available. The prognosis for survival is therefore considered to be poor. After two separate incidences of recurrence with incomplete excision of the tumour, intralesional treatment with cisplatin without excision or debulking was performed on three separate occasions. Intralesional cisplatin injection was performed at monthly intervals for three treatments. Four years post treatment with cisplatin, the horse remained in remission. This case report describes the diagnostic and treatment challenges for successful treatment of a primary haemangiosarcoma on the distal limb of a warmblood foal using intralesional cisplatin chemotherapy. 相似文献