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71.
72.
Ortega C Parilla G De Balogh K De Rosa M Gimeno O Estol L Dobosh D Leguia G Falcon N Fonseca A Torres M Caballero M Quiros J Vilhena MC Villamil LC Cediel N De Meneghi D 《Journal of veterinary medical education》2007,34(4):492-496
Continued contact between humans and animals, in combination with the ever-increasing movement of human and animal populations that is one effect of globalization, contributes to the spread of diseases, often with detrimental effects on public health. This has led professionals involved in both animal health and public health to recognize veterinary public health (VPH) as a key area for their activities to address the human-animal interface. Veterinarians, a profession with major involvement in this field, are in need of specific knowledge and skills to prevent and control public-health problems. As a result, VPH must be directly integrated into veterinary educational programs. At present, only few veterinary schools have specific VPH programs; in most institutions, VPH does not feature as a specific subject in either undergraduate or post-graduate curricula. SAPUVET and SAPUVETNET II are network projects supported by the ALFA program of the European Union (EU). Their main objectives are to reach a common understanding between European and Latin American universities in the definition of the areas in which VPH is important in their respective countries, and to design a harmonized training program for veterinarians in VPH, by making use of new technological applications and innovative teaching methodologies. The elaboration of educational material in combination with case studies presenting real-life problems provides a basis to apply the knowledge acquired on VPH. It is envisaged that the material and modules developed during the two projects will be integrated into the veterinary curricula of the participating universities, as well as in other partner organizations. 相似文献
73.
Fiorella Cazzuli Carolina Bremm Martín Jaurena Dennis Poppi Martín Durante Marcelo Adolfo Benvenutti Jean Victor Savian Thais Devincenzi Pablo Rovira Ximena Lagomarsino Andrés Hirigoyen Fernando A. Lattanzi 《Grass and Forage Science》2023,78(2):306-316
It is unclear to what extent and on which variables does supplementing beef cattle on native grasslands affect sward structure, specifically on the dynamics of its grazing horizons. Three hypotheses were tested: (i) during a grazing down process under similar forage allowance, supplemented animals take longer to finish each grazing stratum, than their unsupplemented counterparts, (ii) in both cases, the upper stratum will be heavily depleted before the subsequent strata are grazed, (iii) some species and/or forage fractions are consumed faster than others, regardless of the animals being supplemented (corn dried distillers grains with solubles, DDGS, at 0.7% of their body weight, BW, on a dry matter, DM, basis) or not. Three blocks of stockpiled native grasslands were used and split into two treatments plots (n = 6), on which either supplemented (S) or control (C) heifers of 10.6 ± 0.6 months of age and an initial BW of 143 ± 9 kg, were used. A 2.5 × 0.5 m observation grid was installed on the sward, generating 384 observation points on each plot. On these observation plots, sward height (SH) and visually assessed green forage mass percentage (%G) were registered every other day for 12 consecutive days. No differences were found between the horizontal grazing dynamics between supplemented and control animals in terms of how they switched from the upper grazing horizon to the successive ones. In both cases, when the upper grazing horizon was heavily depleted, the subsequent horizon was being depleted by its half. Differences of preference for C3 species over C4 was observed for both treatments, but this effect was more meaningful for control animals. Grazing time never fully compensated for the decline in intake rate during depletion throughout the grazing horizons. Pasture intake declined when the animals transition from grazing the top grazing horizons to the lower horizons, irrespective of the level of supplementation. Managing the sward structure in terms of sward height will be beneficial to maximizing individual animal performance, for both C and S animals. Native grasslands paddocks with a greater C3 gasses predominance will always be preferred to C4 dominated paddocks, regardless of an eventual supplementation practice. 相似文献
74.
Evaluation of drought indices to identify tolerant genotypes in common bean bush(Phaseolus vulgaris L.)
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Alefsi David SáNCHEZ-REINOSO Gustavo Adolfo LIGARRETO-MORENO Hermann RESTREPO-DíAZ 《农业科学学报》2020,19(1):99-107
Drought is one of the major abiotic stresses often causing negative impacts on bean crops in the Andean region in Colombia. An experiment under the greenhouse conditions was carried out to assess the effect of a prolonged drought period(15 days) at two different phenological stages(vegetative or reproductive) on grain yield and yield components of five bush bean cultivars(ICA-Cerinza, Bachue, NUA35, Bianca, and Bacatá). Nine tolerance indices including stress susceptibility index(SSI), tolerance(TOL), mean productivity(MP), geometric mean productivity(GMP), stress tolerance index(STI), yield stability index(YSI), yield index(YI), Harmonic mean(HM), and drought sensitivity index(DSI) were calculated based on grain yield under non-stressed(YP) and drought(YS) conditions. Based on the different drought indices, genotypes ICA-Cerinza and NUA35 had the best performance under drought conditions in both studied phases, which reflected in a reduction of grain yield ~≤40%. The biplot analysis also showed a clear superiority of these two genotypes at both phenological stages. Results also showed that SSI was more effective to identify genotypes less affected by drought. The above results allowed us to conclude that ICA-Cerinza and NUA35 may be considered for agricultural areas where long periods of water deficit are expected and can be used in breeding programs for drought tolerance. 相似文献
75.
R. Tiberi A. Niccoli M. Curini F. Epifano M. C. Marcotullio O. Rosati 《Phytoparasitica》1999,27(4):263-272
This paper presents preliminary results on attempts to extract and characterize the volatile secondary metabolites contained
in needles of differentPinus species and to ascertain the role played by these substances on the behavior ofThaumetopoea pityocampa (Denis et Schiffermüller) females, which show a marked preference, during the oviposition period, for some indigenous and
exotic species of host plants existing in mixed formation. Limonene is the most abundant monoterpene extracted fromP. pinea needles, the least favored species of pine processionary caterpillar (PPC) females, although it is present in only very low
amounts in otherPinus species. An increase was observed in limonene production byP. pinea at the start of the flight period of the PPC adult, and subsequently at the beginning of the females’ oviposition period.
Assays carried out in two pine stands in central Italy showed that limonene, emulsified with water and sprayed on foliage
of four different pine species plants,P. sylvestris, P. nigra, P. pinaster andP. radiata, during the PPC oviposition period, provided a satisfactory degree of protection. In fact, the number of egg clusters collected
from treated plants was often lower than the number of egg clusters collected from control plants and was comparable to the
number of egg clusters laid onP. pinea plants. In particular (R)-(+)-limonene, although not produced in nature by pines, was the most effective deterrent. However,
the effect of (S)-(-)-limonene, the enantiomer biosynthesized by pines, was also adequate. 相似文献
76.
Fabricio A. Vigliano Adolfo M. Araujo Andrés J. Marcaccini María V. Marengo Eliana Cattaneo Carina Peirone Lucrecia G. M. Dasso 《Fish physiology and biochemistry》2014,40(2):417-426
Phylogenetic diversity in fish determines high interspecific variability in morphology as well as in physiological parameters. Moreover, several haematological variables and the organ composition of haemolymphopoietic sites may vary according to sex or season. The aim of this study was to establish the haematological parameters and the cellular composition of haemolymphopoietic organs in Odontesthes bonariensis, a commercially valuable fish species in Argentina, and also to determine gender or seasonal variations. Haematocrit exhibited the highest value in summer, while haemoglobin concentration was greater in summer and autumn. Erythrocyte count was higher in spring than autumn and winter, but did not differ with summer. The increase in these variables in seasons with higher water temperatures might be a compensatory mechanism to compensate the lower level of oxygen in the environment. Leucocyte formula and blast haemolymphopoietic cells in spleen and head kidney also showed annual variations since cells related to specific immune response, i.e., lymphocytes and thrombocytes, decrease in winter, whereas cells of the non-specific immune pathways, such as granulocyte, rise. The elevation of a particular type of circulating leucocyte was preceded by an increase in values of its precursor in blood in the previous season. Both, spleen and head kidney were active in haemolymphopoiesis, although with some differences in their activity during different seasons. Males showed higher values of circulating lymphoblasts and granulocytes than females, whereas females exhibited higher values of thrombocytes. This study corroborates the high interspecific variations in haematological parameters in fish that underlines the needing of basic studies in order to assess fish health status in new promising species for aquaculture. 相似文献
77.
Adolfo Rosati Marija Zipani
Silvia Caporali Giuseppe Padula 《Scientia Horticulturae》2009,122(3):399-403
Fruit size is an important parameter both for scientific understanding and for commercial purposes. In many species, mature fruit size is often related to floral ovary size, but no literature exists in olive that demonstrates such a relationship. Previous work suggests that olive cultivars with different fruit sizes have similar cell number and size in the ovary transectional area, but ovary and fruit dry weight was not measured. In the present study, ovary dry weight and fruit dry weight during the whole fruit development season until harvest were measured in olive cultivars with different fruit size, over three years. Flower dry weight was also measured. Fruit weight at harvest was strongly correlated to ovary weight at bloom, both in single-year data and when data from three years were pooled. Flower dry weight, excluding the ovary, was also correlated to ovary dry weight. Ovary dry weight was strongly correlated not only to the fruit dry weight at maturity, but also at any date during fruit development. The mature fruit/ovary dry weight ratio ranged between 1000 and 4000 among cultivars, but was not correlated to the fruit dry weight at maturity. These results suggest that, in olive, fruit weight is genetically controlled through the ovary weight at bloom. This knowledge may have implications in the understanding of fruit set and source-sink relationships in olive. 相似文献
78.
Pedraza-Beltrán P Estrada-Flores JG Martínez-Campos AR Estrada-López I Rayas-Amor AA Yong-Angel G Figueroa-Medina M Nova FA Castelán-Ortega OA 《Tropical animal health and production》2012,44(2):329-336
Tropical grasses are the primary nutrient resource for cattle production in the tropics, and they provide low-cost nutrients
to cattle. However, its production is constrained by seasonal changes and quality; hence, appropriate usage of relatively
inexpensive agricultural by-products is important to profitable livestock production. The objective of the study was to evaluate
the effect of supplementing coffee pulp to dairy cows grazing tropical grasses on milk yield and forage intake. Four multiparous
crossed Holstein–Brown Swiss–Zebu cows of similar weight and milk yield were used. The effect of 10%, 15% and 20% inclusion
of coffee pulp in dairy concentrates on milk yield and forage intake was analysed using a 4 × 4 Latin square design. Results
showed that there were no significant effects (P > 0.05) in grass dry matter intake, milk yield, milk composition body weight and body condition score due to the inclusion
of coffee pulp in the dairy concentrates. It is concluded that coffee pulp can be included at levels of 20% in the concentrate
without compromising significantly (P > 0.05) milk yield, milk composition and grass dry matter intake. It also was concluded that cost of concentrate is reduced
in 20% by the inclusion of coffee pulp. 相似文献
79.
80.
Ruben Francisco Adolfo Paz-Silva Iván Francisco Francisco Javier Cortiñas Silvia Miguélez José Suárez Cristiana Filipa Cazapal-Monteiro José Luis Suárez María Sol Arias Rita Sánchez-Andrade 《Journal of Equine Veterinary Science》2012
Control of horse parasites often omits application of measures to eradicate the free-living stages in pastures and frequently relies on chemotherapy only. Selective therapy was used for Spanish Sport horses grazing either in the same pasture (continuous) or in rotated meadows. In each group, equines exceeding a cutoff value of 300 strongyle eggs per gram of feces received ivermectin or moxidectin. Efficacy of the treatment was assessed by estimating reduction of fecal egg counts and the number of horses shedding parasite eggs (PHR). Coprocultures revealed presence of the cyathostomins Cyathostomum and Gyalocephalus spp. In all treated groups, a 100% value for both reduction of fecal egg counts and PHR against cyathostomins was obtained, and PHR values ranged from 100% to 12%. The longest strongyle egg reappearance period was observed in horses undergoing rotation grazing and receiving ivermectin (9 weeks), compared with a 6-week period recorded for the other treated equines. Our results seem to point that the efficacy of selective therapy in equine herds could be reduced if the horses with fecal egg counts below the threshold value (thus not receiving chemotherapy) remain grazing in the same pastures with the treated ones. It is strongly suggested that interested parties consider performing periodic fecal analyses to monitor fecal egg counts, together with the percentage of horses passing eggs in feces, to improve the effect of this procedure. 相似文献