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191.
Lloyd E. DONALDSON M.V.SC. Ph.D. D. A. Little M.V.SC. William HANSEL Ph.D. 《Australian veterinary journal》1968,44(8):364-366
The duration of oestrus and the interval from onset of oestrus to ovulation has been studied in heifers of Brahman x Shorthorn, Hereford, Shorthorn and mixed dairy breeds following treatment with synthetic progesterone (CAP) and during a subsequent cycle. The animals were under observation for 24 hr a day. No significant differences were observed between breeds in either the length of oestrus or the interval to ovulation; nor could a difference be shown within breeds due to treatment with CAP. The mean duration of oestrus was 13.9 ± 0.5 (SE) hr, and the mean interval from onset of oestrus to ovulation was 26.9 ± 0.6 (SE) hr. 相似文献
192.
The Sierra Madre fault, along the southern flank of the San Gabriel Mountains in the Los Angeles region, has failed in magnitude 7.2 to 7.6 events at least twice in the past 15,000 years. Restoration of slip on the fault indicated a minimum of about 4.0 meters of slip from the most recent earthquake and suggests a total cumulative slip of about 10.5 meters for the past two prehistoric earthquakes. Large surface displacements and strong ground motions resulting from greater than magnitude 7 earthquakes within the Los Angeles region are not yet considered in most seismic hazard and risk assessments. 相似文献
193.
Barn Swallows(Hirundo rustica), a group of passerine birds comprised of six closely related subspecies, are well known throughout their nearly worldwide distribution, in part because of their close association with human settlements.A tractable species for both individual-based and population-level studies, Barn Swallows are a prominent model system in evolutionary, ecological, and behavioral research. Here we review work on sexual selection and population divergence in this species complex, focusing on comparative studies among populations and subspecies.We summarize variation in the targets of mate choice and in the information conveyed by sexually selected traits, and conclude that the benefits advertised by different traits may vary geographically. Finally, we consider the role of sexual selection as a driver of population divergence in this widespread and phenotypically variable species complex. 相似文献
194.
Brown trouts, Salmo trutta, were exposed via aquarial water to 203Hg2+ or to CH3
−203Hg+ alone or together with one of the following S-containing substances: sodium dimethyldithiocarbamate (SMC), sodium diethyldithiocarbamate
(SEC), potassium ethylxanthate (PEX), sodium isopropylxanthate (SIX), sodium diethyldithiophospbate (SEP), sodium diisopropyldithiophosphate
(SIP) or sodium pyridinethione (SPyr). The distribution of the 203Hg2+ and the CH3−203Hg+ in the fishes were then studied by whole-body autoradiography and gamma spectrometry. The results showed that the examined
complexing substances can induce increased uptake of both 203Hg2+ and CH3−203Hg+ by the fishes: for 203Hg2+ most of the complexing substances induced a similar increase in various tissues; for CH3−203Hg+ marked variations were seen for different substances. Determinations of chloroform/water partition coefficients showed that
the examined substances are able to form lipophilic complexes both with Hg2+ and CH3−Hg+. A facilitated penetration of the lipophilic complexes over the membranes of the gills and other tissues may underly the
increments of the tissue-levels of the Hg. It is possible that increased uptake of Hg2+ and CH3−Hg+ induced by complexing substances of this type may have toxicological implications for fishes and for other aquatic organisms. 相似文献
195.
196.
Kate Alexander DMV Howard Dobson BVM & SC DVSC 《Veterinary radiology & ultrasound》2003,44(4):456-464
A study of the ultrasonographic appearance and size of the sciatic, tibial, peroneal, suprascapular, radial, median, and ulnar nerves and a comparison with the anatomic size and location of these nerves in the normal adult horse is reported. Cadavers and live horses were studied. Landmarks for localization and techniques for nerve identification are described. The depth and diameter of each nerve at various locations and the success rate in imaging each nerve are reported. Statistically significant correlations were found between anatomically and ultrasonographically measured nerve depths and diameters. The success rate in identifying nerves was 70% in the live horses and 49% in cadavers, with the deep peroneal nerve being the easiest to identify. Some applications of this technique in horses are discussed. 相似文献
197.
J. B. WHITE F.R.C.V.S. F.A.C.V.Sc G. de CHANEET B.V.SC. 《Australian veterinary journal》1976,52(2):73-79
A survey of the cestode infections of 304 dogs from 134 properties in the Albany area of Western Australia was performed. Purgation was induced by oral administration of arecoline and the purge examined for cestodes. The cestodes found and their infection rates were: Dipylidium caninum 16.4%; Taenia spp 36.5%; T. ovis 8.9%; T. hydatigena 15.1%; T. pisiformis 15.1%; T. serialis 2.3%; Echinococcus granulosus 0.7%; Questionnaires completed on 133 of the 134 properties at the time the dogs were purged showed that:– 73.6% of farmers were feeding raw sheep-meat and 24.8% were feeding raw offal to their dogs; dogs were treated on a regular basis with a cestocide on 23.3% of properties; dogs were allowed to roam on 21.8% of the properties and stray dogs were considered prevalent on 23.3% of properties.
Suggestions for control of Cysticercus ovis are made based on an interpretation of the significance of these findings. 相似文献
Suggestions for control of Cysticercus ovis are made based on an interpretation of the significance of these findings. 相似文献
198.
SC MANOLIS † GJW WEBB † D PINCH† L MELVILLE† G HOLLIS† 《Australian veterinary journal》1991,68(3):102-105
The prevalence of salmonellas in captive Crocodylus porosus and C. johnstoni was investigated at 2 Northern Territory crocodile farms. Similar proportions of each species at one farm (20.0 and 27.8% for C. porosus and C. johnstoni, respectively) carried salmonellas, but at the other farm there was a significant difference between the 2 species (81.0 and 5.0%, respectively). Procedures for the slaughter of crocodiles and processing of crocodile flesh for human consumption are outlined and discussed from the viewpoint of minimising salmonella contamination. The prevalence of salmonellas on flesh for human consumption (16.0% of carcases) was higher than that reported for beef and mutton, but lower than that for poultry products (Murrell 1986). Serotypes most often isolated from cloacai and faecal swabs were S. cerro, S. singapore, S. enteritidis and S. arizonae. Of the 10 serotypes isolated from processed carcases, S. singapore was most frequently isolated (33.3% of serotypes identified). 相似文献
199.
200.