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81.
82.
Transmission of infection between animals is possible when using multidose syringes. The possibility of infection spreading can be reduced by using a telescopic device which fits the syringe barrel and is topped by a cap containing plastic foam impregnated with biocide. Under laboratory conditions, and continually contaminating the needle with various bacteria, infection could not be cultured in broth until after at least 25 injections and in most cases contamination did not occur after 50 injections. When culture was undertaken on solid media breakdowns occurred more frequently, possibly because the agar became lodged in the needle and shielded the bacteria from the biocide.  相似文献   
83.
Histophilus ovis was isolated from 29 sheep in 20 flocks and 2 artificial insemination (AI) centres in southern New South Wales from 1984 to 1990. The clinical and pathological findings were consistent with previous reports and included polyarthritis (7 flocks), epididymo-orchitis (5), meningoencephalitis (3), pneumonia (3), septicaemia (2), mastitis (1) and metritis (1). Six sheep had meningoencephalitis, a syndrome not previously associated with H ovis infection in sheep, which was similar pathologically to thromboembolic meningoencephalitis in cattle, caused by the related organism, Haemophilus somnus. H ovis was isolated from the semen of 12-month-old rams in a flock that had polyarthritis due to H ovis, in 4-month-old ram lambs and from the uterus of a ewe in a flock that had sporadic cases of H ovis septicaemia.  相似文献   
84.
SUMMARY Fifty-nine reports of suspected adverse drug reactions (ADRs) were received by the Adverse Drug Reaction Subcommittee of the Australian Veterinary Association from April 1992–March 1993 inclusive. The number of reports received/number of animals involved per species was: dogs (30/43); cats (11/14); horses (8/10); cattle (9/30); ferret (1/1). Of these, 37 (63%) were classified as definite ADRs and 12 (20%) as probable ADRs. In 10 (17%) reports an ADR could not be substantiated or there was insufficient information available to make a decision. Twenty-three reports involved apparent hypersensitivity reactions and 5 reports were associated with ‘off-label’ use. Of the definite and probable reports of suspect ADRs the most frequent types of drugs involved were antimicrobials (9 reports), anthelmintics (9 reports), vaccines (7 reports), insecticides (6 reports), vitamin preparations (6 reports), topical anti-inflammatory/antimicrobial/antifungal skin preparations (3 reports) and nonsteroidal anti-inflammatory preparations (3 reports). Single reports concerning definite or probable ADRs to an anticholinergic, an anaesthetic agent, a corticosteroid, an anabolic steroid and a chondroprotective drug were received.  相似文献   
85.
The aim of this study was to analyse the effect of filtration through Sephadex on the subpopulation characteristics of the boar semen. For this purpose 3 ml of 16 commercial doses of fresh diluted boar semen were filtered through a Sephadex G‐15/Polypropylene column. Motility parameters were analysed by a CASA system and statistical study was performed by SAS package using the VARCLUS and the FASTLUST procedures. Statistical study revealed four subpopulations in fresh boar semen, as previously had described (Theriogenology 61: 673–690).Total motility was higher in control than in filtered semen, but there were not statistical differences (65.63 ± 9.65 vs 41.40 ± 9.02). Moreover, the analysis did not show many changes neither in the characteristics nor in the distribution of the four subpopulations. As example although ALHmed of filtered samples were slightly higher, there were only significant differences (p < 0.001) in two subpopulations (subpopulation 2 : 2.2 ± 0.05 in control vs 2.7 ± 0.08 in filtered. Subpopulation 3 : 4.5 ± 0.11 in control vs 5.8 ± 0.23 in filtered semen). HME was also statistically different (p < 0.005) in one subpopulation, showing great values in filtered semen (1.7 ± 0.15 vs 3.0 ± 0.30). In conclusion, the filtration by Sephadex/Polypropylene column does not cause strong changes in subpopulation sperm distribution.  相似文献   
86.
This study was performed to test the effect that two separate, daily, constant-light regimes of both 9 and 16 h could have on the main parameters of boar-semen quality analysis, as well as on the motile sperm subpopulations structure and the ability of its conservation at 16 degrees C. Results show that both luminous regimes have slight, specific effects on the main parameters of boar-semen quality analysis, as well as on the motile sperm subpopulations structure. Furthermore, the conservation ability at 16 degrees C of boar semen was not significantly different between both photoperiods. When a temporal study was performed, results showed that semen quality and motility parameter changes were stabilized at nearly constant values from the second month of the study to the last month in both luminous regimes, indicating a rapid light-related effect on testicular function. Our results indicate that light regimes oscillating from 9 h daily to 16 h daily are of little importance in the control of boar-semen quality in a farming environment.  相似文献   
87.
Fluxes of protons with energies of approximately 550 kev and electrons with energies of approximately 300 kev which exceed approximately 10(4) and 10(5) cm(-2) sec(-1), respectively, have been discovered in the magnetosphere of Mercury. Electron fluxes > 10(3) cm(-2) sec(-1) also are observed in the outbound pass of the Mariner 10 spacecraft throuigh the magnetosheath. The intensity versus time profiles of the particle fluxes in the magnetosphere appear with sudden onsets of approximately 10(4) cm(-2) sec(-1) beginning at interplanetary background levels and persisting for times equivalent to their being distriblited spatially over regions having a scale size comparable to the planetary radius. For a spectral form dJ/dE alpha E-gamma, where J is the differential particle intensity and E is the kinetic energy, the typical values of gamma are gamma(p) = 5.5 for protons above 500 kev and gamma(e) >/= 9 for electrons above 170 kev. Large coherent electron intensity oscillations (variations of factors of 10 to 100) have been discovered with characteristic periods of approximately 6 seconds and with higher frequency components. In some cases proton bursts are found in phase with these oscillations. On the basis of the experimental evidence and a knowledge of the general magnetic field intensities and directions along the trajectory of Mariner 10 provided by the magnetic field observations, it is shown that the radiation events observed in the magnetosphere and magnetosheath are transient and are not interpretable in terms of stable trapped particle populations. Furthermtiore, experimental evidence strongly supports the view that the particles are impulsively accelerated and that the acceleration source is not more distant from the point of observation along lines of force than approximately 8 x 10(3) to 16 x 10(3) kilometers (3 to 6.5 units of Mercury's radius). Candidates for the regions most likely to be sources of particle acceleration are discussed, namely, the magnetotail and the magnetosheath. It is pointed out that the phenomena discovered at Mercury will place more stringent conditions on allowed mnodels for electron and proton acceleration than have heretofore been possible in studies within the earth's magnetosphere.  相似文献   
88.
89.
Antimicrobial resistance of feline staphylococci in south-eastern England   总被引:1,自引:0,他引:1  
Staphylococcus aureus is reported as the predominant feline staphylococcal pathogen. There is concern that cats may transfer resistant staphylococci to humans. In this study, staphylococci were obtained from skin and mucosae of 20 domestic cats, 9 with lesions, and 10 healthy feral cats. Species were identified by DNase and API ID32 Staph tests. Of 187 isolates, 21.4% were coagulase-positive and predominately from lesional cats; 90% of these were Staphylococcus intermedius . Coagulase-negative species were isolated equally in all three groups. All isolates were susceptible to coamoxiclav, cephalexin and bacitracin. Twenty-two, including 18 coagulase-negative isolates, showed some resistance to cotrimoxazole, lincomycin, enrofloxacin or oxytetracycline. Two isolates were resistant to more than one antibiotic. More resistant isolates were obtained from feral cats ( P < 0.01). The results suggest that S. intermedius is the principal coagulase-positive species. Antibiotic resistance is generally low amongst feline staphylococci. Higher resistance amongst feral cats suggests exposure to environmental antibiotics.  相似文献   
90.
Objective To assess the effects of the duration of anaesthesia, position of recumbency, mode of ventilation, anaesthetic drug protocol, patient age and type of surgical procedure on the usefulness of capnometry as a measure of the partial pressure of arterial carbon dioxide (Paco 2) during general anaesthesia in horses. Design A prospective study compared the Paco 2 values with those of partial pressure of end-tidal carbon dioxide (ETco 2) in horses anaesthetised for elective or emergency surgical procedures. The difference between Paco 2 and ETco 2 (Paco 2− ETco 2) and the physiological dead space to tidal volume ratio (VD/VT) were calculated. The effects of the study parameters on these variables was determined. Results The agreement between Paco 2 and ETco 2 was poor. Paco 2− ETco 2 and VD/VT during the first 60 min of anaesthesia was significantly less than after 60 min of anaesthesia. Mode of ventilation, position of recumbency, anaesthetic drug protocol, patient age and type of procedure did not have a significant affect on either value. Conclusions Paco 2− ETco 2 in anaesthetised horses can be large, making ETco 2 unreliable as a predictor of Paco 2 and for assessment of pulmonary ventilation. For anaesthesia lasting less than 60 min at least one blood gas analysis of an arterial blood sample is required to assess Paco 2− ETco 2. Arterial blood gas analysis should be repeated after 60 min of general anaesthesia.  相似文献   
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