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991.
RM Korman JJ Cerón TG Knowles EN Barker PD Eckersall S Tasker 《Veterinary journal (London, England : 1997)》2012,193(2):433-438
The pathogenicity of Haemoplasma spp. in cats varies with 'Candidatus Mycoplasma haemominutum' (CMhm) causing subclinical infection while Mycoplasma haemofelis (Mhf) often induces haemolytic anaemia. The aims of this study were to characterise the acute phase response (APR) of the cat to experimental infection with Mhf or CMhm, and to determine whether chronic feline immunodeficiency virus (FIV) infection influences this response. The acute phase proteins serum amyloid A (SAA), haptoglobin (Hp) and α-1-acid glycoprotein (AGP) concentrations were measured pre-infection and every 7-14days up to day 100 post-infection (pi) in cats infected with either Mhf or CMhm. Half of each group of cats (6/12) were chronically and subclinically infected with FIV. Marbofloxacin treatment was given on days 16-44 pi to half of the Mhf-infected cats, and on days 49-77 pi to half of the CMhm-infected cats. FIV-infected animals had significantly lower AGP concentrations, and significantly greater Hp concentrations than non-FIV-infected cats when infected with CMhm and Mhf, respectively. Both CMhm and Mhf infection were associated with significant increases in SAA concentrations, while AGP concentrations were only significantly increased by Mhf infection. Mhf-infected cats had significantly greater SAA concentrations than CMhm-infected animals. Both Mhf and CMhm infections were associated with an APR, with Mhf infection inducing a greater response. Chronic FIV infection appeared to modify the APR, which varied with the infecting Haemoplasma species. 相似文献
992.
993.
Use of ultrasound in the reproductive management of dairy cattle 总被引:1,自引:0,他引:1
Quintela LA Barrio M Peña AI Becerra JJ Cainzos J Herradón PG Díaz C 《Reproduction in domestic animals = Zuchthygiene》2012,47(Z3):34-44
The significant decrease in fertility observed in dairy cattle during the last few decades and increasing requirements by the farmers have made a regular control of reproduction indispensable to urgently identify and solve potential problems affecting reproductive efficiency. Traditionally, the main diagnostic methods used for reproductive control in cattle included rectal palpation, inspection of vaginal discharge and vaginoscopy. Since the 1990 s, the use of ultrasound (US) has become a common diagnostic method as a result of the new advances made in the development of US scans: smaller size, high level of autonomy, high image quality and accessible prices. Ultrasound improves accuracy in the diagnoses of stages of the oestrous cycle, ovarian and uterine pathologies, and pregnancy diagnosis. In addition, it facilitates the diagnosis of alterations during pregnancy (embryo mortality, foetal malformations, etc.) and helps determining foetal sex from day 55 of pregnancy. 相似文献
994.
C Gómez-Posada JM Londoño 《Folia primatologica; international journal of primatology》2012,83(1):56-65
We evaluated population density, group structure and home range of red howler monkeys in a bamboo forest fragment in the Cordillera Central mountain range of Colombia. We estimated a density of 377.7 individuals/km(2), which is a higher density than normally reported for this species. The average home range size was 3.6 ± 1.1 ha. We found large groups (15.1 ± 4.0 individuals) with subgrouping behavior (daily divisions in foraging subgroups), and a high number of adult and subadult individuals of both sexes per group (mean of 5 males and 7 females per group). The small home range and large group size observed may be related to the high density of howler monkeys in this fragment, which we suggest could be the result of limited dispersal opportunities for these monkeys. The results illustrate the great plasticity of the genus Alouatta, which enables the monkeys to live in a wide range of conditions. 相似文献
995.
996.
Biezyński J Skrzypczak P Piatek A Kościółek N Drozdzyńska M 《Polish journal of veterinary sciences》2012,15(2):285-290
Osteochondrosis is a common and clinically important joint disorder that occurs in human and many species of animals such as pigs, horses and dogs. The aim of this article is to present the results of conservative and surgical treatment of Osteochondrosis dissecans (OCD) and to compare the recovery time in relation to race, age and extent of cartilage damage. The study was performed on 36 dogs of both sexes, aged from 4 to 24 months, weighing 12-70 kg, of different breeds (predisposed and non-specific for this disease). All patients underwent clinical, orthopedic and radiological examination through which the location of OCD changes in the shoulder joint and the degree of this problem were established. Based on the examinations the patients were qualified for particular treatment procedures. Control tests were performed after 14, 30 and 60 days, which allowed for a precise evaluation of the progress of therapy. Achieved results indicate that dogs age and the lesions extent in the shoulder joint have an impact on the outcome of treatment. Studies showed that the best therapeutic effects were obtained in dogs aged 6-10 months, which underwent surgery. The study proved that the early diagnosis of OCD strongly influence the recovery rate and may inhibit the development of degenerative changes in the joint (DJD). 相似文献
997.
Yellow starthistle (Centaurea solstitialis L.) is a nonnative pest of rangelands that decreases forage quality and yield. Mowing may control starthistle effectively and complement herbicide use in an integrated pest management strategy, but little research has investigated its effects on nontarget vegetation. We monitored biomass and seedbank size of annual and perennial species, in addition to starthistle, in response to 3 yr of mowing treatments, either mowing alone or in combination with solarization tarps or thatch removal. All mowing treatments were very effective at reducing starthistle biomass and seedbank: mowing alone reduced biomass 92 ± 2%, mowing with thatch removal 91 ± 1%, and mowing with solarization 95 ± 1%. Compared to seedbank sizes in the control plots, yellow starthistle seedbank decreased by 100% (mowing alone), 92% (mowing + thatch removal), and 100% (mowing with solarization) after 3 yr of treatment. Mowing also significantly improved perennial species' biomass. Annual species' biomass varied on a year-to-year basis but was not significantly affected by any treatment. Seedbank sizes of annuals and perennials also did not differ according to mowing treatment. This research indicates that late-season mowing can effectively reduce starthistle biomass without adverse effects on other vegetation and that mowing alone is sufficient to reduce starthistle seedbank size without additional methods of decreasing seed rain. 相似文献
998.
L. Miranda-Aragón E.J. Trevi o-Garza J. Jiménez-Pérez O.A. Aguirre-Calderón M.A. González-Tagle M. Pompa-García C.A. Aguirre-Salado 《林业研究》2012,23(3):345-354
Determining underlying factors that foster deforestation and delineating forest areas by levels of susceptibility are of the main challenges when defining policies for forest management and planning at regional scale. The susceptibility to deforestation of remaining forest ecosystems (shrubland, temperate forest and rainforest) was conducted in the state of San Luis Potosi, located in north central Mexico. Spatial analysis techniques were used to detect the deforested areas in the study area during 1993-2007. Logistic regression was used to relate explanatory variables (such as social, investment, forest production, biophysical and proximity factors) with susceptibility to deforestation to construct predictive models with two focuses: general and by biogeographical zone.In all models, deforestation has positive correlation with distance to rainfed agriculture, and negative correlation with slope, distance to roads and distance to towns. Other variables were significant in some cases, but in others they had dual relationships, which varied in each biogeographical zone. The results show that the remaining rainforest of Huastecaregion is highly susceptible to deforestation. Both approaches show that more than 70% of the current rainforest area has high and very high levels of susceptibility to deforestation. The values represent a serious concern with global warming whether tree carbon is released to atmosphere. However, after some considerations, encouraging forest environmental services appears to be the best alternative to achieve sustainable forest management. 相似文献
999.
Ana Vasques Paula Maia Mariana Pedro Concei??o Santos V. Ramón Vallejo J. Jacob Keizer 《Annals of Forest Science》2012,69(4):499-507
? Context
Maritime Pine forests cover important mountain areas in Portugal and are known to be a particularly fire-prone forest type. Understory composition plays an important role in maintaining biodiversity and ecosystem services after recurrent wildfires.? Aims
This study aims to improve the knowledge on the germination ecology of understory species of Maritime Pine forests, focusing on the importance of seed provenance, including in relation to germination enhancement by heating.? Methods
The selected species were Cistus ladanifer L., Erica australis L., Erica umbellata L., Pterospartum tridentatum L. (Willk), and Genista triacanthos Brot. Seeds were collected from two or three distant populations. Besides a control treatment, two heating regimes were applied, i.e., 100°C during 5?min and 80°C during 30?min.? Results
Heating treatments significantly enhanced germination in four out of the five species. Differences between provenances were most evident for C. ladanifer and E. australis, especially following the heating treatments. Overall, the seeds from the southern provenances germinated better and, at the same time, were smaller.? Conclusion
The present results confirmed that seed provenance should not be ignored as a key factor in germination ecology, so that further work is needed to untangle the roles of environmental and genetic factors in the observed differences between provenances. 相似文献1000.
José Ramón Arévalo Guacimara González-Delgado Beatriz Mora José María Fernández-Palacios 《Journal of Forest Research》2012,17(2):184-192
The laurel forest of Anaga is the most emblematic community of the Canarian Archipelago. Restoration programs are being developed
to increase laurel forest area on the island of Tenerife. Structural and spatial characteristics determine many aspects of
the community, including regeneration patterns, disturbance level, stand history. In spite of the importance of this information
for restoration, few quantitative studies have been conducted on laurel forest dynamics. We analyzed two stands of the Anaga
laurel forest of different aspect. The main difference between the two sites was the wind exposure, one leeward and the other
windward. Regeneration, spatial distribution of regeneration, tree species composition, asexual regeneration and environmental
parameters were analyzed in three 50 × 50 m plots at each site. Both sites differ in important aspects such as species richness,
species composition, asexual regeneration and dead tree composition, while they are not different in basal area, density,
density of regeneration and density of dead trees. Both sites have had similar management in the last century. Asexual regeneration
is able to maintain the present species composition, while sexual regeneration is able to offer future changes in the canopy
composition. Regeneration strategies and the effect of some environmental characteristics should be considered in restoration
programs. 相似文献