An evaluation of an oral formulation of moxidectin against selected anthelmintic-resistant and -susceptible strains of nematodes in lambs     

Bisset SA  Vlassoff A  McMurtry LW  Elliott DC  Cobb RM  Kieran PJ  Wood IB 《New Zealand veterinary journal》1992,40(3):97-100

The efficacy of an oral formulation of the newly developed parasiticide, moxidectin, was tested against benzimidazole-resistant Haemonchus contortus, Trichostrongylus colubriformis, and Nematodirus spathiger, levamisole-resistant Ostertagia circumcincta, and susceptible Cooperia curticei infections in weaned lambs. Thirty-two lambs were experimentally infected with mixed doses of the above strains of nematodes. They were allocated into four treatment groups by stratified randomisation using liveweights and faecal egg counts 28 days later. One group received moxidectin at 0.2 mg/kg liveweight, one group oxfendazole at 4.5 mg/kg liveweight, one group levamisole at 7.5 mg/kg liveweight and the last group remained untreated as the control. Worm burdens in the lambs at slaughter 10 days after oral treatment confirmed the resistance status of the nematode strains used, and showed that moxidectin had a greater than 99.9% efficacy (p<0.01) against all of them. No adverse effects due to treatment with moxidectin were observed in any of the animals.  相似文献   

Growth and erosion of thin solid films     

Bales GS  Bruinsma R  Eklund EA  Karunasiri RP  Rudnick J  Zangwill A 《Science (New York, N.Y.)》1990,249(4966):264-268

Thin films that are grown by the process of sputtering are, by and large, quite unlike the smooth, featureless structures that one might expect. In general, these films have a complicated surface morphology and an extended network of grooves and voids in their interiors. Such features can have a profound effect on the physical properties of a thin film. The surface irregularities and the bulk defects are the result of a growth instability due to competitive shadowing, an effect that also plays a role in geological processes such as erosion. For amorphous thin films, the shadow instability can be described by a remarkably simple model, which can be shown to reproduce many important observed characteristics of thin film morphology.  相似文献   

Global climate change and intensification of coastal ocean upwelling   总被引：2，自引：0，他引：2  

Bakun A 《Science (New York, N.Y.)》1990,247(4939):198-201

A mechanism exists whereby global greenhouse warning could, by intensifying the alongshore wind stress on the ocean surface, lead to acceleration of coastal upwelling. Evidence from several different regions suggests that the major coastal upwelling systems of the world have been growing in upwelling intensity as greenhouse gases have accumulated in the earth's atmosphere. Thus the cool foggy summer conditions that typify the coastlands of northern California and other similar upwelling regions might, under global warming, become even more pronounced. Effects of enhanced upwelling on the marine ecosystem are uncertain but potentially dramatic.  相似文献   

Nephrotoxicity in dogs associated with methoxyflurane anesthesia and flunixin meglumine analgesia   总被引：2，自引：2，他引：0       下载免费PDF全文

Mathews KA  Doherty T  Dyson DH  Wilcock B  Valliant A 《The Canadian veterinary journal. La revue veterinaire canadienne》1990,31(11):766-771

Uremia unexpectedly developed in five dogs 24 hours after undergoing thoracotomy in a student laboratory. In all dogs general anesthesia had been maintained with methoxyflurane, muscle relaxation had been induced with gallamine, and each dog received a single intravenous dose of 1.0 mg/kg flunixin meglumine for analgesia upon termination of anesthesia. In a subsequent group of dogs undergoing an orthopedic procedure, we assessed the effects on renal function of methoxyflurane anesthesia plus oxymorphone, or of methoxyflurane or halothane anesthesia in combination with a single IM 1.0 mg/kg dose of flunixin meglumine. Significant elevations in serum urea and creatinine values, and necrosis of collecting ducts and loops of Henle, were noted only in the dogs receiving methoxyflurane and flunixin meglumine.

We conclude that the use of combination of methoxyflurane and flunixin meglumine is contraindicated in dogs.

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Use of epidural morphine to relieve pain in a horse   总被引：2，自引：1，他引：1       下载免费PDF全文

Valverde A  Little CB  Dyson DH  Motter CH 《The Canadian veterinary journal. La revue veterinaire canadienne》1990,31(3):211-212

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Ontario. Osseous metaplasia of the renal pelvis in slaughter swine          下载免费PDF全文

Bundza A 《The Canadian veterinary journal. La revue veterinaire canadienne》1990,31(7):529

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Building knowledge and understanding: enduring assets of society     

Herschman A 《Science (New York, N.Y.)》1981,213(4514):1353-1365

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Foreign travel     

Herschman A 《Science (New York, N.Y.)》1980,210(4471):763-778

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Nitrate poisoning in cattle     

Malestein A  Geurink JH  Schuyt G  Schotman AJ  Kemp A  Th van 't Klooster A 《The Veterinary quarterly》1980,2(3):149-159

Summary In a series of experiments the effect of administering KNO(2) was studied, during parturition, on the capability of oxygen transport of maternal blood and on oxygen transfer to foetal blood. The following blood parameters were analysed, MHb percentage, pO(2), O(2)-saturation, pH, pCO(2), and (NO(2)) in maternal arterial blood (carotid art.) and venous blood (jugular vein) and in foetal arterial blood (umbilical art.) and venous blood (umbilical vein). The relative O(2)-saturation was calculated from the estimated O(2)-saturation by multiplying with the factor Hb (mmol/1) minus MHb (mmol/1), divided by Hb (mmol/1). In addition, blood pressure in the carotid artery, heart rate, and respiration rate in the dam were continuously recorded for some hours. A dosage of 9 to 12 mg of NO(2)/kg body weight intravenously or of 30 mg of NO(2)/kg body weight orally to the dam caused much higher MHb percentages and NO(2) contents in the maternal blood than in the foetal blood. In maternal blood the ratio of NO(2) content td MHb percentage was proportional to that in foetal blood. In the arterial blood, MHb percentages were almost as high as in the venous blood. After administering of nitrite, relative O(2)-saturation dropped simultaneously with the increase in methaemoglobin. Nitrite treatment caused a drop in the maternal blood pressure; heart rate and respiration rate increased. O(2)-saturation in the blood in the umbilical vein was much lower in the animals with nitrite treatment than in those without. These experimental results show clearly that the oxygen capacity of the blood decreases after nitrite treatment. In pregnant cows the oxygen supply to the foetus will be adversely affected after nitrate intake, especially by the lower oxygen transfer via the placenta, though hardly at all by methaemoglobin formation in the foetal blood. When the oxygen transfer to the foetal blood decreases too sharply, intra-uterine death and ultimately abortion may result.  相似文献   

Science and technology: resources for our future     

Herschman A 《Science (New York, N.Y.)》1978,201(4362):1207-1213

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