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71.
Phenotypic and genetic parameters for body traits in the giant freshwater prawn (Macrobrachium rosenbergii) in India 下载免费PDF全文
Bindu R Pillai Pa Luan Lalrinsanga Raul W Ponzoni Hooi Ling Khaw Kanta Das Mahapatra Swagatika Mohanty Gunamaya Patra Namita Naik Haramohan Pradhan Pallipuram Jayasankar 《Aquaculture Research》2017,48(12):5741-5750
Phenotypic and genetic parameters were estimated for three body traits (harvest weight, carapace length and standard length) and for adult male morphotypes of the giant freshwater prawn Macrobrachium rosenbergii in a fully pedigreed synthetic population in India. The data set included 9,173 progeny produced over four generations from 162 sires and 234 dams. Variance components and genetic parameters were estimated fitting an animal model using the residual maximum‐likelihood methodology. The heritabilities for harvest body weight (HW), carapace length (CL) and standard length (SL) were moderate (0.22 ± 0.056, 0.22 ± 0.055 and 0.25 ± 0.059 respectively). The common environmental effects for HW, CL and SL were 0.10 ± 0.020, 0.08 ± 0.018 and 0.10 ± 0.021 respectively. As M. rosenbergii is sexually dimorphic, we estimated heritabilities within each sex. Heritability of HW in females (0.27 ± 0.068) was greater than that in males (0.15 ± 0.057). CL and SL followed the same pattern. The occurrence of male morphotypes is a unique characteristic of adult populations of M. rosenbergii. Populations from culture ponds exhibit a wide range of sizes. To examine whether there was a heritable component in male morphotype frequencies, we treated male morphotypes as traits. The additive genetic variance (and hence the heritability) was zero for male morphotype, indicating that selective breeding to increase the proportion of desirable male morphotypes would not be effective. The genetic correlations among body traits were all positive, high and approaching unity. The results are discussed in relation to selection plans for the giant freshwater prawn. 相似文献
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The role of indirect binding of host proteins through glycosaminoglycans (GAGs) on adherence and internalization of Streptococcus uberis to bovine mammary epithelial cells was evaluated. Preincubation of S. uberis with GAGs followed by incubation with fetal bovine serum (FBS), bovine milk or milk proteins resulted in greater adherence to and internalization of S. uberis into mammary epithelial cells than observed in untreated controls. Highest values were detected, when final incubation was done with milk. Greater adherence to and internalization into mammary epithelial cells were observed when heparin sulfate (HEP) and milk were used compared with any other GAG and FBS. When individual milk proteins were used, greatest adherence and internalization were observed when S. uberis strains were pretreated with HEP followed by treatment with beta-casein. The findings of this study illustrate a pathogenic strategy of S. uberis that may occur during the very early stages of infection. 相似文献
73.
Assessing the spatial distribution of Tuta absoluta (Lepidoptera: Gelechiidae) eggs in open‐field tomato cultivation through geostatistical analysis 下载免费PDF全文
74.
Pesticides and reduced‐risk insecticides,native bees and pantropical stingless bees: pitfalls and perspectives 下载免费PDF全文
Although invertebrates generally have a low public profile, the honey bee, Apis mellifera L., is a flagship species whose popularity likely derives from the products it provides and its perceived ecological services. Therefore, the raging debate regarding honey bee decline has surpassed the realm of beekeepers, academia, industry and regulatory agencies and now also encompasses non‐governmental agencies, media, fiction writers and the general public. The early interest and concern about honey bee colony collapse disorder (CCD) soon shifted to the bigger issue of pollinator decline, with a focus on the potential involvement of pesticides in such a phenomenon. Pesticides were previously recognised as the potential culprits of the reported declines, particularly the neonicotinoid insecticides owing to their widespread and peculiar use in agriculture. However, the evidence for the potential pivotal role of these neonicotinoids in honey bee decline remains a matter of debate, with an increased recognition of the multifactorial nature of the problem and the lack of a direct association between the noted decline and neonicotinoid use. The focus on the decline of honey bee populations subsequently spread to other species, and bumblebees became another matter of concern, particularly in Europe and the United States. Other bee species, ones that are particularly important in other regions of the world, remain the object of little concern (unjustifiably so). Furthermore, the continuous focus on neonicotinoids is also in need of revision, as the current evidence suggests that a broad spectrum of compounds deserve attention. Here we address both shortcomings. © 2015 Society of Chemical Industry 相似文献
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Sheri Spiegal Richard E. Estell Andres F. Cibils Darren K. James H. Raul Peinetti Dawn M. Browning Kirsten B. Romig Alfredo L. Gonzalez Andrew J. Lyons Brandon T. Bestelmeyer 《Strength and Conditioning Journal》2019,72(4):590-601
Adopting livestock with heritage genetics may help to improve the sustainability of agriculture on rangelands with harsh, challenging conditions. In the Chihuahuan Desert, preliminary evidence suggests that heritage Raramuri Criollo exploit a greater variety of range resources than do conventional cattle. Accordingly, the use of Raramuri Criollo may help sustain vegetation and soils, as well as agricultural production. To explore these possibilities, we used Global Positioning System collars to track Angus × Hereford and Raramuri Criollo cows in a 1 535-ha pasture in southern New Mexico in June–December 2008. As predicted on the basis of past research, home range sizes of Raramuri Criollo exceeded those of Angus × Hereford during seasons with low forage availability—by 31.4 ± 6.5 ha during Pregreenup and 17.2 ± 6.5 ha during Drydown—but sizes converged during more productive seasons (Greenup 1, Greenup 2). Angus × Hereford allotted more daily time to resting, with the difference most pronounced during Drydown (71.1 ± 21.1 min day? 1). Angus × Hereford had twice as many hotspots of use (locations with multiple visits of long duration), with seasonal timing and location corresponding with distribution patterns known to impact desirable natural resources. Raramuri Criollo more strongly preferred the Bare/Forbs ecological state with seasonal timing that possibly signals an ability to use nutritious forbs on open ground despite summer heat. Results are consistent with conjectures that compared with conventional cattle, Raramuri Criollo have greater daily mobility and wider spatial distribution during dry seasons. Although not directly measured, results also suggest that the heritage breed has superior heat tolerance and lower impact on desirable natural resources. These findings provide evidence that Raramuri Criollo can support sustainable livestock production in the Chihuahuan Desert, but direct measurements of profitability and environmental effects are needed before adoption can be recommended widely. 相似文献
77.
Oscar Ortiz Guillermo Frias Raul Ho Hector Cisneros Rebecca Nelson Renee Castillo Ricardo Orrego Willy Pradel Jesus Alcazar Mario Bazán 《Agriculture and Human Values》2008,25(3):419-431
Participatory research (PR) has been analyzed and documented from different points of view, with emphasis on the benefits generated for farmers. The effect of PR on organizational learning has, however, received little attention. This paper analyzes the interaction between a research and a development institution, the International Potato Center (CIP) and CARE in Peru, respectively, and makes the case that PR can contribute to creating a collaborative learning environment among organizations. The paper describes the evolution of the inter-institutional collaborative environment between the two institutions for more than a decade, including an information-transfer period (1993–1996), an action-learning period (1997–2002), and a social-learning period (2003–2007). Several lessons learned from each period are described, as are changes in institutional contexts and stakeholders’ perceptions. The case shows that research and development-oriented organizations can interact fruitfully using PR as a mechanism to promote learning, flexibility in interactions, and innovation. Interactions foster the diffusion of information and the sharing of tacit knowledge within and between organizations, which in turn influences behavior. However, the paper also argues that long-term inter-organizational interactions are needed to facilitate learning, which can be used to influence the way organizations implement their interventions in a constantly changing environment. 相似文献
78.
Semi-natural forests, which naturally regenerate after timber harvesting, provide distinct opportunities for dead wood (DW) management for biodiversity. We described DW pool and sources of its variation during the first decade after final felling in Estonia, hemiboreal Europe. Depending on forest type, the mean post-harvest volumes of above-ground DW ranged from 70 to 119 m3 ha?1. Final felling generally did not reduce downed coarse woody debris (CWD) because many sawn logs were left on-site, and soil scarification was rarely used. However, subsequent decay of downed CWD appears to be accelerated due to the increased ground contact of logs, so that even the relatively small inputs from live retention trees observed (5 m3 ha?1 per decade) can be ecologically significant. While final felling greatly reduced snag abundance, the mortality of retained live trees generally balanced their later losses. The volumes of downed fine woody debris in conventional cutover sites were roughly double that of pre-harvest forests. Slash harvest caused an approximately twofold reduction in downed DW and resulted in CWD volumes that were below mature-forest levels. The results indicate that the habitat quality of cutovers critically depends both on the retention and on the post-harvest management of biological legacies. In Estonia, the necessary improvements include more careful retention of snags in final felling, selecting larger retention trees, focusing slash harvest on the fine debris of common tree species, and providing snags of late-successional tree species. 相似文献
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Raul Neghina Adriana-Maria Neghina Iosif Marincu Roxana Moldovan Ioan Iacobiciu 《Veterinary parasitology》2009,159(3-4):328-331
The main source of trichinellosis in Romania is insufficiently cooked pork infected with Trichinella spiralis. Timis, the largest Romanian county, is located in the western part of the country where pork and traditional food prepared from pork are extensively consumed. The objective of the present study was to conduct a retrospective investigation of the incidence of human trichinellosis in Timis County over a period of 16 years (1990–2005). The medical records of 521 patients were used as the source of data. Patients were hospitalized at “Victor Babes” Hospital of Infectious Diseases from Timisoara during the period 1990–2005. The highest number of cases was recorded in 1994 (16.90%) and most of the patients were in the age group of 20–29 (23.22%). Males and females were almost equally affected by trichinellosis. The clinical pattern was mainly characterised by myalgia (72.55%) and edema (54.12%). Laboratory investigations included mainly elevated eosinophil and leucocyte values. In 52.02% of the patients, the hospitalization period ranged between 8 and 14 days. Most of the patients were from urban areas, but often the source of infection was found in rural areas. Hospitalization of the affected patients required considerable health care resources. The decreasing incidence of trichinellosis in Romania over the last decade has been due to sanitary education programmes for both swine breeders and consumers. 相似文献