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1.
Bats in captivity reproduce well and contraceptive techniques are needed. In initial attempts at vasectomy using a prescrotal approach, it was difficult to identify the mesoductus deferens. The technique described here uses a scrotal approach with exteriorization of the testis, followed by identification and ligation of the mesoductus deferens. Nine Egyptian fruit bats (Rousettus aegyptiacus) underwent vasectomy for this study. No postoperative complications were seen (n = 18 testes), but some of the testes (5/18, 27%), which previously moved freely from the scrotum to the abdominal cavity, were still adhered to the scrotal sac 14 mo postoperatively. This technique appears safe, is fast, and is relatively easy to perform.  相似文献   
2.
Traumatic elbow luxation was diagnosed in a common squirrel monkey (Saimiri sciureus) and a bonnet macaque (Macaca radiata). In the common squirrel monkey, the luxation was complicated by an ulnar fracture and would not stay reduced when attempts at closed reduction were made. The luxation was surgically reduced and a transarticular type I external skeletal fixator was placed. In the bonnet macaque, closed reduction was performed and the elbow was stabilized using a cast. Both monkeys regained good function of the injured elbows.  相似文献   
3.
Delayed flower bud formation was recorded when a single spray of 200 ppm ethephon was applied to rooted chrysanthemum cuttings three days after planting in long days. The cuttings were of three American garden cvs and an autumn-flowering cv known to bud readily in long days. The technique might be useful for propagators and growers of chrysanthemums to delay bud formation on stock plants and on rooted cuttings.  相似文献   
4.
Summary

Short-day (SD) and long-day (LD) photoperiodic treatments were compared, at equal light integral, for their effects on the seedling growth of four bedding plant species: geranium, impatiens, pansy and petunia. Total leaf area was frequently increased by LD given either by day-extension lighting or night-break lighting, but this response was inconsistent and varied greatly between species and experiments. In contrast, leaf greenness measured using a SPAD-502 meter, a measure of chlorophyll content per unit area of leaf, was consistently and significantly increased in LD in all four species. However, night-break lighting may have been somewhat less effective than day-extension lighting. Increasing the day-extension lighting from 16 h to 24 h gave no further intensification of greenness. Consistent with increases in leaf greenness, total dry weight was generally increased in LD, and increases were of a similar magnitude to those given by doubling the daily light integral. The promotional effect of LD on chlorophyll content appears to have been largely ignored or overlooked in recent years, but this may be because simple methods for measuring ‘greenness’ have only recently become widely available.  相似文献   
5.
A number of different types of edge effects on experimental plots are defined, and it is shown that they are frequently important in agroforestry experiments. Methods of eliminating edge effects, either at the design or the analysis stage, are described. Computer simulations, based on uniformity data, are used to investigate the efficacy of neighbour-balanced designs, with and without neighbour terms, for reducing the problem of neighbour effects between different treatments. It is concluded that, while neighbour-balanced designs may be useful in certain situations or in combination with other methods, it is preferable to eliminate edge effects by using adequate guard rows. Recommendations are therefore made concerning the correct use of guard areas in agroforestry experimentation.  相似文献   
6.
Summary A mathematical model was constructed to determine the theoretical effectiveness of selection under various protocols in initial trials of clonally propagated crops. Effectiveness was quantified as the proportion of top phenotypes selected that can also be expected to be the best genotypes in trial. In the absence of replication there is a non-linear increase in this proportion with increase in broad-sense heritability. The proportion of best genotypes included is reduced as the intensity of selection increases. Replication effectively raises broad-sense heritability. The resulting increases in selection effectiveness are quantified for three levels of single-plant heritability (0.1, 0.5 and 0.9) and three selection intensities (0.1, 0.01 and 0.001) using a model based on the Normal Distribution and in which it is assumed that the trial area increases in size in direct relation to the degree of replication.When the trial area is of fixed size, replication reduces the number of genotypes that can be tested and the effectiveness of selection is, therefore, calculated with regard to the initial population of genotypes which could have been tested in the absence of replication. This showed that replication has a marginal benefit only where very high selection intensities are applied to characters with very low heritabilities. In other cases, replication is not beneficial since increases in selection effectiveness fail to compensate for good genotypes left in the seed packet. This conclusion proved to be equally valid when genetic variation was non-Normally distributed. Any increase in trial area for initial selection is best employed by increasing the total number of genotypes and growing just one representative plant of each. These conclusions could be relevant in other circumstances such as the evaluation stage of the single-seed descent breeding method for sexually propagated crops.  相似文献   
7.
Isotopic variability in barium, neodymium, and samarium in carbonaceous chondrites reflects the distinct stellar nucleosynthetic contributions to the early solar system. We used 148Nd/144Nd to correct for the observed s-process deficiency, which produced a chondrite 146Sm-142Nd isochron consistent with previous estimates of the initial solar system abundance of 146Sm and a 142Nd/144Nd at average chondrite Sm/Nd ratio that is lower than that measured in terrestrial rocks by 21 +/- 3 parts per million. This result strengthens the conclusion that the deficiency in 142Nd in chondrites relative to terrestrial rocks reflects 146Sm decayand earlyplanetary differentiation processes.  相似文献   
8.
A greater one-horned Asian rhinoceros (Rhinoceros unicornis) presented for presumed ocular trauma to the left eye, with secondary bacterial infection, resulting in severe and progressive corneal ulceration. Following a poor response to medical therapy, the animal was anesthetized for further examination, and a bulbar conjunctival pedicle graft performed. This graft failed by 48-h postsurgery as a result of self-trauma. The animal was re-anesthetized, and a free island tarsoconjunctival graft performed. This second procedure was successful, resulting in globe preservation, cosmesis, and functional vision in the affected eye.  相似文献   
9.
This study aimed at assessing the pathogenicity of two Vibrio splendidus-related species and evaluating the influence of the origin and annual life cycle of mussels on their sensitivity during a bacterial challenge. Thus, in vivo infection assays were made with Vibrio crassostreae 7T4_12 and Vibrio splendidus 3G1_6, over, respectively, thirteen and 9 months, on adult blue mussels from five recruitment areas in France. Two bacterial concentrations were tested: one consistent with the loads of Vibrio spp. in environment and mussel tissues (~105 CFU/ml) and another one much higher (~108 CFU/ml). The tested environmental concentration has no pathogenic effect whatever the time of year, the strain used and the origin of mussels. However, at the highest concentration, a pathogenic effect was observed only at specific moments, and one of the origins appeared to be more resistant. The physiological state of mussels—depending on the time of year—seemed significant in mussels’ sensitivity, as their recruitment origin. This study is the first to test the pathogenicity of V. splendidus-related strains at concentrations close to what is found in the wild, over the annual cycle of mussels, and considering their origin.  相似文献   
10.
Leishmaniosis is an important sand fly transmitted protozoan disease of dogs and humans. In northern Europe, infection is mainly restricted to dogs that have travelled to and/or from endemic areas of the Mediterranean region during periods when there is high sand fly exposure, mostly between March and November. Infected dogs in these areas in northern latitudes are a potential reservoir should incursion of a competent vector occur. However, information on the scale of the potential reservoir in the UK is lacking. Confirmed cases of canine leishmaniosis entering the United Kingdom between 2005 and 2007 were identified using diagnostic samples submitted to the Department of Clinical Veterinary Science, University of Bristol and from collaborating laboratories (n = 257). All study dogs had clinico-pathological signs compatible with leishmaniosis, as typically reported in endemic countries and were leishmania positive in real time or conventional PCR tests, IFA serology and/or tissue microscopic examination for amastigote identification. Information obtained from each case included travel history, habitat, clinico-pathological findings and geographical location once located in the UK. The majority of dogs with complete travel history (n = 183) had spent at least 6 months in Spain (105/183), 28/183 were rescued from re-homing centres in the country of origin and 26/183 entered the UK with confirmed leishmaniosis. Once located in the UK, the majority of positive cases were resident in south and central England. The spectrum of clinico-pathological signs for this group of dogs is similar to that reported in endemic countries. These data confirm that a potentially significant reservoir of infected dogs is resident in areas where future climatic conditions may support introduction of competent vectors.  相似文献   
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