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131.
E. Carina H. Keskitalo Johanna Liljenfeldt 《Scandinavian Journal of Forest Research》2014,29(5):473-484
The goal of nature conservation is often implemented on productive forest land largely by means of forest certification – a market-driven, voluntary system of third-party verification of the fulfilment of specific goals. This study assesses how certification requirements are being implemented in various organisations in the forest sector at various levels, and the problems and opportunities identified at each level in order to implement the requirements of the standard. Based on interviews with 34 stakeholders in Sweden, the study demonstrates that forest certification is a communication issue: it places great demands on communication or “information logistics” between different parts of the felling and forest management chain, from the top management to the contractor in the field. Integration with environmental performance systems, clarity in the division of responsibility, formalisation of requirements for forest planning and further integration of a culture of continuous improvement and internal reporting could support implementation of the certification system. 相似文献
132.
Gerson Antonio Oliveira Júnior Joanir Pereira Eler Johanna Ramírez-Díaz José Bento Sterman Ferraz Mário Luiz Santana Jr. 《Tropical animal health and production》2014,46(6):1031-1036
The objective of this study was to evaluate the impact of including weaning management group (WMG) as an uncorrelated random effect in the genetic evaluation of postweaning traits. Data from 186,507 Nellore animals' sons to 1,734 sires and 75,016 cows were analyzed. Three single-trait models were studied. These models included the contemporary group (CG) as a fixed effect and age of animal at measurement and age of dam at calving as covariates, in addition to the direct additive breeding value as random effect. The CGs for postweaning traits varied between models which included or not WMG as part of the concatenation of fixed effects. In the model in which WMG was not part of the CG, the trait was included as an uncorrelated random effect. The results suggest that although no significant effects were observed on genetic parameter estimates or animal ranking, the inclusion of WMG as an uncorrelated random effect increased the number of observations per CG and contributed to maintaining animals in the analysis that would be discarded because they were in a CG with a small number of observations. This model could therefore be recommended for the genetic evaluation of this Nellore population. 相似文献
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134.
Naylê Francelino Holanda Duarte Carlos Henrique Alencar Kellyn Kessiene de Sousa Cavalcante Francisco Gustavo Silveira Correia Phyllis Catharina Romijn Danielle Bastos Araujo Silvana Regina Favoretto Jorg Heukelbach 《Zoonoses and public health》2020,67(2):186-192
The intensification of dog, cat and livestock vaccination campaigns significantly reduced rabies cases in humans and domestic animals in Ceará State, Brazil. However, sylvatic animals—bats (order Chiroptera), wild canids, raccoons and non‐human primates— remain as reservoirs for the virus. Our hypothesis is that surveillance and monitoring of rabies virus in bats, especially passive surveillance, is of fundamental importance, besides the implementation of health education and strengthening of surveillance actions in humans exposed to aggressions. Thus, we assessed the occurrence of rabies virus in animals focusing on bats, before and after launching of the Sylvatic Rabies Surveillance Program in 2010. Surveillance data from the 184 municipalities of Ceará State were analysed, collected during the periods 2003–2010 (active surveillance) and 2011–2016 (passive surveillance), respectively. A total of 13,543 mammalian samples were received for rabies diagnosis from 2003 to 2016. Of these, 10,960 were from dogs or cats (80.9%), 1,180 from bats (8.7%), 806 from other sylvatic animals (foxes, marmosets, raccoons; 6.0%) and 597 from herbivores (cattle, goats, sheep, equines, pigs; 4.4%). A total of 588 (4.3%) samples were positive for rabies. About 8.4% (99/1,180) of the bat samples were infected with rabies virus, 92 (92.9%) of these were from non‐haematophagous bat species and 7 (7.1%) from haematophagous species. The number of bat samples received and infection rates increased considerably, after a shift from active surveillance (9/355 [2.5%] samples positive), to passive surveillance (90/825 [10.9%] samples positive). Surveillance of rabies virus in bats is fundamental for human and domestic animal health in Ceará State. Bats have to be considered as targets in surveillance and control programmes. Virus lineages should be characterized to increase knowledge on transmission dynamics of sylvatic rabies virus to domestic animals and the human population, and to provide additional evidence for planning and implementation of improved control measures. 相似文献
135.
Methylmercury in runoff from the Svartberget Catchment in northern Sweden during a stormflow episode 总被引:1,自引:0,他引:1
Kevin Bishop Ying -Hua Lee Catharina Pettersson Bert Allard 《Water, air, and soil pollution》1995,80(1-4):221-224
The dynamics of MeHg during rain-driven runoff episodes are important in calculating the output of MeHg from forested catchments. These dynamics may also provide insight into the processes controlling MeHg output from soils to surface waters. The concentrations of MeHg, Hg-tot, TOC and associated chemistry were observed during a rain-driven, July runoff episode on two forested tributaries of the Svartberget Catchment, as well as at the outlet of a mire in the headwaters of that catchment. TOC concentrations in runoff increased during the episode. Hg-tot concentrations also tended to increase (from 3 to between 4 and 7 ng L?1), though the timing of that increase varied. MeHg concentrations, on the other hand, tended to decrease. The decrease was slight in the two forested tributaries (ca. 0.1 ng L?1), but greater in the mire runoff (from 0.8 to ca 0.3 ng L?1). These data are set in relation to a hypothesis about the processes which control MeHg output. 相似文献
136.
137.
Phenotypic and marker‐assisted pyramiding of genes for resistance to zucchini yellow mosaic virus in oilseed pumpkin (Cucurbita pepo) 下载免费PDF全文
We report on the identification of phenotypic and molecular markers for genes introgressed into oilseed pumpkin Cucurbita pepo from C. moschata germplasm originating in Nigeria, Portugal and Puerto Rico, which provide resistance against zucchini yellow mosaic virus (ZYMV) and on pyramiding these genes for improved and long‐lasting field protection of oilseed pumpkins. One SCAR and two SSR markers have been found for three dominant resistance genes, Zym‐0, Zym‐1 and Zym‐2. Characteristic reactions to ZYMV inoculation of plants carrying the recessive genes for resistance zym‐4* and zym‐6 have been defined. Described are procedures and results of pyramiding various combinations of these genes in oilseed pumpkin using the three markers and the specific phenotypic reactions to infection of some of these genes. The putative combination of all six resistance genes in one genotype resulted in a resistance that appeared to be at least as strong as or even stronger than that of the resistance source germplasm in C. moschata. 相似文献
138.
Lindahl Johanna F. Vrentas Catherine E. Deka Ram P. Hazarika Razibuddin A. Rahman H. Bambal R. G. Bedi J. S. Bhattacharya C. Chaduhuri Pallab Fairoze Nadeem Mohamed Gandhi R. S. Gill J. P. S. Gupta N. K. Kumar M. Londhe S. Rahi M. Sharma P. K. Shome R. Singh R. Srinivas K. Swain B. B. 《Tropical animal health and production》2020,52(1):387-396
Tropical Animal Health and Production - Brucellosis is an important zoonosis worldwide. In livestock, it frequently causes chronic disease with reproductive failures that contribute to production... 相似文献
139.
Mutua Florence Lindahl Johanna Randolph Delia 《Tropical animal health and production》2020,52(2):859-870
Tropical Animal Health and Production - Consumers have a right to safer foods, and traceability is one approach to meeting their expectations. Kenya does not have an operational animal traceability... 相似文献
140.