Searching for the quark-gluon plasma     

Bertsch GF 《Science (New York, N.Y.)》1994,265(5171):480-481

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Geminga and the astronomy of isolated neutron stars     

Bignami GF 《Science (New York, N.Y.)》1994,263(5143):46-47

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Prevalence of antibodies to equine viruses in the Netherlands     

de Boer GF  Osterhaus AD  van Oirschot JT  Wemmenhove R 《The Veterinary quarterly》1979,1(2):65-74

Summary The prevalence of antibodies to various viruses was investigated in a series of serum samples collected from horses in the Netherlands between 1963 and 1966 and from 1972 onwards. Neutralizing antibodies to equine rhinopneumonitis virus, equine arteritis virus and to equine rhinovirus types 1 and 2 were detected in respectively 76%, 14%, 66% and 59% of the equine serum samples tested. The observed incidence of serum samples positive to equine adenovirus in the complement fixation test was 39%. Precipitating antibodies to equine infectious anaemia virus were detected only in serum samples from two horses imported from abroad. Haemagglutination inhibiting antibodies to Myxovirus influenzae A / equi-1, M. Influenzae A / equi-2, and Reovirus types 1, 2, and 3 were present in respectively 82%, 50%, 10%, 33% and 3.6% of the serum samples tested. The most frequently observed incidence of antibodies to the various equine respiratory viruses occurred in the groups of horses having repeatedly contact with other horses.  相似文献   

Retinal disease in the N.Z. working dog     

Hughes PL  Joyce GF 《New Zealand veterinary journal》1981,29(12):241

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An inactivated vaccine for the control of bluetongue virus serotype 16 infection in sheep in Italy     

Savini G  Ronchi GF  Leone A  Ciarelli A  Migliaccio P  Franchi P  Mercante MT  Pini A 《Veterinary microbiology》2007,124(1-2):140-146

Because no suitable products are at the moment available to safely control the spread of BTV-16 in Europe, an inactivated vaccine was produced from the reference field isolate of bluetongue virus serotype 16. One group of six sheep was vaccinated subcutaneously with the inactivated vaccine twice, on days 0 and 28, whereas a second group of eight sheep was inoculated with saline solution and used as mock-vaccinated control animals. Seventy-eight days after the first vaccination, all sheep were inoculated subcutaneously with a suspension containing 10(6.3) TCID(50) of a virulent reference BTV-16 isolate. Apart from a transient inflammatory reaction at the injection site, no adverse effects were reported following vaccination. All vaccinated animals developed high titres (7.3-9.3log(2)(ED50%/50 microl)) of virus-specific neutralising antibodies and were resistant to challenge with BTV-16. Conversely, following challenge, control animals developed hyperthermia and long lasting high-titre viraemia.  相似文献   

Selective capture of transcribed sequences (SCOTS) of Actinobacillus pleuropneumoniae in the chronic stage of disease reveals an HlyX-regulated autotransporter protein     

Baltes N  Buettner FF  Gerlach GF 《Veterinary microbiology》2007,123(1-3):110-121

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Influence of supplementary fibrolytic enzymes on the fermentation of corn and grass silages by mixed ruminal microorganisms in vitro   总被引：4，自引：0，他引：4  

Wallace RJ  Wallace SJ  McKain N  Nsereko VL  Hartnell GF 《Journal of animal science》2001,79(7):1905-1916

This study was done to determine the effectiveness of supplementary enzymes at increasing the fiber digestion by ruminal microorganisms and to assess whether enzyme activity limits the rate of fiber digestion in ruminal digesta. In vitro comparisons of enzyme activities in two feed enzyme preparations (A and B) with enzyme activities extracted from ruminal fluid indicated that the addition of fibrolytic enzymes at the application rates recommended by the manufacturers would not be expected to increase significantly glycanase and polysaccharidase activities in ruminal fluid. Preparations A and B both increased (P < 0.001) the rate of gas production from freeze-dried corn and grass silages in in vitro incubations with ruminal fluid, but only at concentrations much higher than recommended application rates. Autoclaved controls had little or no effect. Ultrafiltration of enzyme B indicated that most stimulation was due to components >100 kDa, which is consistent with the cause of the stimulation being enzyme activity. Fibrolytic enzymes from other sources were also able to stimulate gas production: increased rates of gas production were observed in seven out of eight combinations of "cellulase" and corn or grass silage (P < 0.05). The comparison of glycanase and polysaccharidase activities with gas-stimulatory activity in the different enzyme preparations indicated that the highest correlation was between increased gas production and enzyme activity against microgranular cellulose (P < 0.05). In a wider range of fibrolytic enzyme preparations, those with endo-(beta-1,4)- or exo-(beta-1,4)-xylanase activity equal to that of preparation A did not produce similar increased rates of fermentation of corn silage when glucanase activity was low (P > 0.05). In contrast, preparations with glucanase activity similar to enzyme A gave at least as great (P < 0.05) an improvement in gas production than enzyme A, irrespective of xylanase activity. It was concluded that enzyme activity, probably a type of endo-(beta-1,4)-glucanase activity, limits the rate of fermentation of corn and grass silage in the rumen. Enzyme supplements of the type used in these experiments are unlikely to possess sufficient activity to overcome this limitation by direct application to ruminal digesta, implying that treatment of the ration prefeeding will be key to harnessing the potential of exogenous fibrolytic enzymes in ruminant nutrition.  相似文献   

A novel nutritional strategy to prevent milk fever and stimulate milk production in dairy cows     

Wilson GF 《New Zealand veterinary journal》2001,49(2):78-80

AIMS: To assess the efficacy of a feed supplement designed to reduce the dietary availability of calcium when fed during the last 2-3 weeks of pregnancy, on the incidence of postparturient hypocalcaemia (milk fever) and on milksolids (MS) production in pasture-fed dairy cows in early lactation. METHODS: In Experiment 1, late-pregnant Holstein/Friesian cows, 4-10 years old, grazing pasture, were either fed the supplement (1 kg/cow/day) for 2-4 weeks prior to calving (n=11) or no supplement (n=10). Plasma calcium concentrations were measured immediately before and after a 20 h fast intended to induce hypocalcaemia at the end of this period, 1-7 days before the cows calved. In Experiment 2, mixed-breed dairy cows, 3-10 years old in 7 commercial dairy herds were fed the same supplement (1 kg/cow/day) for 1-3 weeks immediately prior to calving (n=565) or no supplement (n=614), and incidences of clinical milk fever and MS production at 6-9 weeks post calving were compared between groups. RESULTS: In Experiment 1, plasma calcium concentrations were higher (p=0.01) in supplemented than in non-supplemented cows after fasting, indicating reduced susceptibility to fasting-induced hypocalcaemia. In Experiment 2, the incidence of milk fever was lower (6.4% vs 17.1%, p=0.001) and MS production was higher (p=0.01) in supplemented than in non-supplemented cows. CONCLUSIONS: These preliminary results demonstrate that feeding a supplement designed to reduce dietary calcium availability for 2-4 weeks immediately prior to calving reduced the susceptibility of cows to fasting-induced hypocalcaemia, reduced the incidence of clinical milk fever and increased MS production in early lactation. CLINICAL RELEVANCE: The concept and product reported here have potential to provide dairy farmers with a practical means to prevent hypocalcaemia and improve milk production during early lactation.  相似文献   

Some clinical effects of midazolam premedication in propofol-induced and isoflurane-maintained anaesthesia in dogs during ovariohysterectomy     

Stegmann GF  Bester L 《Journal of the South African Veterinary Association》2001,72(4):214-216

In a randomised, placebo-controlled clinical trial, anaesthesia was induced with propofol (4 mg/kg) after intravenous premedication with or without midazolam (0.1 mg/kg), in a group of 8 dogs scheduled for ovariohysterectomy. Midazolam administration induced acute behavioural changes, and increased reflex suppression after propofol induction. Compared to the control group, the dose required to obtain loss of the pedal reflex was significantly reduced by 37%, and the end-tidal isoflurane concentration during maintenance, reduced by 23%.  相似文献   

Observations on some cardiopulmonary effects of midazolam, xylazine and a midazolam/ketamine combination in the goat     

Stegmann GF 《Journal of the South African Veterinary Association》1999,70(3):122-126

Xylazine, midazolam and a midazolam/ketamine combination were administered to 6 goats in a randomised 3-way block design. All goats received all treatments with at least a 7-day interval between treatments. Statistically significant (P < 0.05) changes were observed in some of the measured cardiopulmonary variables for xylazine and midazolam/ ketamine. Xylazine administration resulted in statistically significant decreases in minute volume, arterial partial pressure of oxygen, heart rate and mean arterial blood pressure. The increase in arterial partial pressure of carbon dioxide was not statistically significant. For the midazolam/ketamine combination, the decrease in tidal volume was statistically significant, but not the decrease in minute volume and increase in arterial partial pressure of carbon dioxide. The decrease in the arterial partial pressure of oxygen was also statistically significant. The mean arterial blood pressure for the combination was statistically significantly higher compared to xylazine. The changes in cardiopulmonary variables after midazolam administration were not statistically significant, such as tidal and minute volume, arterial partial pressure of oxygen and carbon dioxide. However, clinically significant effects such as hypoventilation and hypoxia were observed after its administration. The change in mean arterial blood pressure was minimal.  相似文献