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101.
Reptile medicine has emerged as a specialty area within the broader field of zoological medicine. It encompasses the medical needs of approximately 7,500 vertebrate species. This vertebrate class is highly diversified, having biological and medical peculiarities that differ both between and within major groups. Historically, veterinarians who have become recognized specialists with reptiles have had limited formal training in their medical management. The pet reptile trade is a multi-million-dollar business, and the popularity of reptiles as pets has resulted in a need for more veterinarians with training in their medical management. While few private practices have high volumes of reptile cases, many small-animal practices will have the opportunity to see a significant number of reptiles on an annual basis. Most practitioners with reptile medical expertise have merged their experiences as reptile pet owners with the principles of veterinary medicine taught in veterinary college. Several North American veterinary colleges have reptile medicine courses, and most have didactic and clinical courses in exotic and zoo animal medicine that include lectures and practical experience. Most accredited zoological medicine residency training programs include training in reptile medicine. The case load and interest in reptile medicine will probably never be sufficient to lead the average veterinary college to develop much more than what is currently offered. Consequently, those few colleges having more extensive course offerings, both didactic and clinical, will serve as educational centers for this discipline. Future Web-based teaching programs in reptile medicine will allow students nationally and internationally to have access to instructional material that can be continually updated. 相似文献
102.
Whole blood from 33 healthy captive Asian elephants (Elephas maximus) was analyzed for 12 trace elements: aluminum, chromium, manganese, cobalt, nickel, copper, zinc, arsenic, selenium, cadmium, mercury, and lead for the purpose of estimating preliminary baseline population parameters for these minerals. Metals were quantified by inductively coupled plasma mass spectroscopy. Baseline ranges for all animals and for all trace elements were comparable to normal concentrations reported in other species. This is the first report of normal trace element levels in the blood of captive elephants. 相似文献
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Ruth Rodríguez‐Bermúdez Ramiro Fouz Marta Miranda Inmaculada Orjales Antonio Humberto Hamad Minervino Marta Lpez‐Alonso 《Reproduction in domestic animals》2019,54(6):902-911
Organic farming has traditionally given preference to indigenous breeds that are well adapted to local conditions; however, current trends towards increased yields may produce less robust animals with potentially low fertility. The Holstein‐Friesian breed dominates dairy sector, although there is a general concern that these cows may not be well adapted to organic systems. This study aims to evaluate the reproductive performance of organic dairy herds in northern Spain, by comparing organically reared Holstein‐Friesian with their counterparts reared on conventional farms and also with other organically reared breeds and crosses. Reproductive parameters were obtained for individual cows on organic, conventional pasture‐based and conventional zero‐grazing farms. The reproductive performance of Holstein‐Friesian cows was slightly better in organic systems than in pasture‐based conventional systems, but not than in zero‐grazing conventional systems. The comparison of reproductive performance of Holstein‐Friesian from organic and conventional systems and with other organically reared breeds and crosses enabled us to demonstrate that it is not the organic system that constrains the reproductive performance of Holstein‐Friesian, but that the manifestation of oestrus is less marked than in other breeds. Breeding selection considering reproductive traits and appropriate management of oestrous detection would improve the reproductive performance of Holstein‐Friesian cows. 相似文献
105.
Genetic structure of eighteen local south European beef cattle breeds by comparative F-statistics analysis 总被引:3,自引:0,他引:3
106.
Lorena A. Berruezo Guadalupe E. Mercado Cárdenas Eleonora del M. Harries Sebastián A. Stenglein Ramiro N. Curti Marcela S. Rodriguero Marta Z. Galván 《European journal of plant pathology / European Foundation for Plant Pathology》2018,150(4):1065-1081
Phenotypic traits are regularly used to diagnose the development of Fusarium head blight (FHB) in the field, whereas mycotoxin accumulation in wheat grains can only be accurately evaluated through costly methods, such as high–performance liquid chromatography (HPLC). The aim of this study was to determine whether: (i) the results provided by existing commercial decision support tools could be anticipated using phenotypic measurements, including a novel technique of computer–assisted image analysis of spikes; and (ii) these measurements could avoid using HPLC. We monitored the FHB development during two consecutive years in highly contaminated plots in the Burgundy region (France). Contamination by crop residues was simulated through a field inoculation with barley grains artificially colonized by Fusarium graminearum. The development of the disease on spikes and harvested grains was assessed on one tolerant and two susceptible wheat varieties. The accumulated amounts of mycotoxins were measured in harvested grains using HPLC. As expected, the measured traits revealed that the inoculum responsible for infection on spikes mainly came from residues left on the soil surface, and the susceptible varieties were more diseased than the tolerant variety. Weather conditions had a strong effect on disease development. The novel computer–assisted image analysis technique had a better prediction power of deoxynivalenol accumulation, was more objective and time–saving than classical visual symptom assessments. This assessment method could be suitable to supplement the use of existing prediction tools and might avoid systematic and costly mycotoxin measurements in likely infected plots. 相似文献
107.
Herbivory may be an important factor affecting seedling survival of exotic species invading new habitats. We evaluated the effect of vertebrate herbivory on the seedling survival of two widely planted and invasive tree species (Pinus radiata and Eucalyptus globulus), in a Mediterranean-type ecosystem of central Chile. An important role of herbivory on seedling survival of these two species in their introduced ranges has previously been documented. However, this has mainly been evaluated in forest plantations where habitat and vegetation conditions differ from wild habitats in which invasion occurs. We planted seedlings with and without protection against vertebrate herbivores in different aspects (a mesic south-facing slope and a xeric north-facing slope) and vegetation cover (open sites and sites with patchy tree cover). We found that regardless of aspect or vegetation cover, herbivory, in this case mainly caused by exotic vertebrates, significantly and negatively affected seedling survival of both species. However, while the effect of herbivory on P. radiata was significant in every vegetation and habitat condition, for E. globulus, the effect of herbivory was significant only for open sites in the mesic habitat. These results suggest that, as observed in forestry plantations, vertebrate herbivory may constrain seedling establishment of these two exotic trees and potentially impede the invasion. However, the importance of herbivory in controlling exotic species may vary depending on the vegetation and habitat conditions in some species such as E. globulus. 相似文献
108.
Pantoja-Guerra Manuel Ramirez-Pisco Ramiro Valero-Valero Nelson 《Journal of Soils and Sediments》2019,19(4):1850-1865
Journal of Soils and Sediments - The effect of a prototype of humic bio-conditioner (H-BC) was assessed on the development of edaphic properties and the growth of maize plants in an edaphic... 相似文献
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Ana M. García-López Ramiro Recena Manuel Avilés Antonio Delgado 《Journal of Soils and Sediments》2018,18(3):727-738