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61.
Sonja Brodt Gail Feenstra Robin Kozloff Karen Klonsky Laura Tourte 《Agriculture and Human Values》2006,23(1):75-88
While questions about the environmental sustainability of contemporary farming practices and the socioeconomic viability of
rural communities are attracting increasing attention throughout the US, these two issues are rarely considered together.
This paper explores the current and potential connections between these two aspects of sustainability, using data on community
members’ and farmers’ views of agricultural issues in California’s Central Valley. These views were collected from a series
of individual and group interviews with biologically oriented and conventional farmers as well as community stakeholders.
Local marketing, farmland preservation, and perceptions of sustainable agriculture comprised the primary topics of discussion.
The mixed results indicate that, while many farmers and community members have a strong interest in these topics, sustainable
community development and the use of sustainable farming practices are seldom explicitly linked. On the other hand, many separate
efforts around the Valley to increase local marketing and agritourism, improve public education about agriculture, and organize
grassroots farmland preservation initiatives were documented. We conclude that linking these efforts more explicitly to sustainable
agriculture and promoting more engagement between ecologically oriented farmers and their communities could engender more
economic and political support for these farmers, helping them and their communities to achieve greater sustainability in
the long run.
Sonja Brodt is a former program evaluation specialist with the University of California Integrated Pest Management Program. Her current
research focuses on extension and adoption of integrated pest management strategies by California growers and the impacts
of pesticide safety training programs on farmworkers.
Gail Feenstra is a food systems analyst at the University of California Sustainable Agriculture Research and Education Program (SAREP).
She coordinates SAREP’s Community Development and Public Policy grants program and conducts outreach and education to academic
and community-based groups to build their capacity and leadership skills for developing sustainable community food systems.
Robin Kozloff is a social science researcher and consultant in agricultural and land use policy.
Karen Klonsky is an extension specialist at the University of California at Davis in the Department of Agricultural and Resource Economics.
Her research focuses on the economic viability of organic and sustainable farming systems as well as the evolution of the
organic market.
Laura Tourte is county director and farm advisor at the University of California Cooperative Extension in Santa Cruz County. Her research
and extension activities currently focus on farm management and marketing for small-scale growers. 相似文献
62.
Antonio Reverter Brad C Hine Laercio Porto-Neto Yutao Li Christian J Duff Sonja Dominik Aaron B Ingham 《Journal of animal science》2021,99(3)
In animal breeding and genetics, the ability to cope with disease, here defined as immune competence (IC), with minimal detriment to growth and fertility is a desired objective which addresses both animal production and welfare considerations. However, defining and objectively measuring IC phenotypes using testing methods which are practical to apply on-farm has been challenging. Based on previously described protocols, we measured both cell-mediated immune response (Cell-IR) and antibody-mediated immune response (Ab-IR) and combined these measures to determine an animal’s IC. Using a population of 2,853 Australian Angus steers and heifers, we compared 2 alternative methods to combine both metrics into a single phenotype to be used as a tool for the genetic improvement of IC. The first method, named ZMEAN, is obtained by taking the average of the individual metrics after subjecting each to a Z-score standardization. The second, ImmuneDEX (IDEX), is a weighted average that considers the correlation between Cell-IR and Ab-IR, as well as the difference in ranking of individuals by each metric, and uses these as weights in the averaging. Both simulation and real data were used to understand the behavior of ZMEAN and IDEX. To further ascertain the relationship between IDEX and other traits of economic importance, we evaluated a range of traits related to growth, feedlot performance, and carcass characteristics. We report estimates of heritability of 0.31 ± 0.06 for Cell-IR, 0.42 ± 0.06 for Ab-IR, 0.42 ± 0.06 for ZMEAN and 0.370 ± 0.06 for IDEX, as well as a unity genetic correlation (rg) between ZMEAN and IDEX. While a moderately positive rg was estimated between Cell-IR and Ab-IR (rg = 0.33 ± 0.12), strongly positive estimates were obtained between IDEX and Cell-IR (rg = 0.80 ± 0.05) and between IDEX and Ab-IR (rg = 0.85 ± 0.04). We obtained a moderately negative rg between IC traits and growth including an rg = −0.38 ± 0.14 between IDEX and weaning weight, and negligible with carcass fat measurements, including an rg = −0.03 ± 0.12 between IDEX and marbling. Given that breeding with a sole focus on production might inadvertently increase susceptibility to disease and associated antibiotic use, our analyses suggest that ImmuneDEX will provide a basis to breed animals that are both highly productive and with an enhanced ability to resist disease. 相似文献
63.
64.
Subalpine meadows, which traditionally were mown every other year, are particularly rich in plant species, especially forbs. Near Davos (Switzerland) we compared the vegetation of mown sites with that of sites grazed for up to 50 years by non-lactating cows. We recorded an overall mean of 51.5 plant species per 4×4 m plot. Among grazed sites, evenness decreased with time since conversion to grazing (−0.11 in 50 years; P<0.05), suggesting progressive vegetation change, which may eventually result in the loss of species. Ground cover by forbs tended to be higher in mown than in grazed sites (by 7.2%; P<0.1). The proportion of not-clonally colonising perennial species decreased after conversion to grazing (−7.72%; in 50 years, P<0.05), while the cover by graminoid species increased (+14.2% in 50 years; P<0.1). More intensively grazed sites had a lower cover of dwarf shrubs and higher cover of legume species (P<0.05). Because grazing negatively affects both botanical richness and agricultural quality, mowing of traditionally mown subalpine meadows should be maintained, and recently grazed meadows should be reconverted to mowing. 相似文献
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67.
Faruk Bogunić Sonja Siljak-Yakovlev Edina Muratović Fatima Pustahija Safer Medjedović 《Annals of Forest Science》2011,68(1):179-187
• Introduction
The most common representatives of the European mountain pine complex (Pinus mugo s.l.) are P. mugo s.s. and Pinus uncinata. 相似文献68.
69.
Mycoplasma synoviae is a major pathogen of chickens and turkeys, causing respiratory disease and infectious synovitis. M. synoviae haemagglutinin VlhA is an abundant surface-exposed lipoprotein and immunodominant antigen. Post-translational cleavage of VlhA generates two proteins, MSPB and MSPA. MSPB, the amino-terminal end of VlhA, is a lipoprotein of about 40-50 kDa but can appear in truncated forms (tMSPB) of about 20-30 kDa. The aim of this study was to determine whether MSPB and tMSPB can stimulate chicken macrophages to secrete NO and cytokines. Macrophages derived from chicken monocytes (MDM) or the MQ-NCSU macrophage cell line were stimulated with M. synoviae protein extracts containing MSPB or tMSPB, as well as with purified MSPB and tMSPB. Proteins from detergent extractions induced IL-6 secretion in MDM and NO secretion in MQ-NCSU. Both MSPB and tMSPB were capable of inducing NO secretion in MQ-NCSU, as well as IL-6 and IL-1beta in MDM. The activity of IL-6 induced by purified tMSPB was similar to the effect of 60 pg/ml of recombinant chicken IL-6. The effect of IL-1beta induced by tMSPB was comparable to the effect of 10 ng/ml of recombinant IL-1beta. Whereas all samples containing MSPB were able to induce NO, IL-6 and IL-1beta, it seemed that the purified tMSPB of about 20 kDa was the most potent in its ability to induce IL-6 and IL-1beta in MDM. Compared to MSPB, tMSPB lacks about 200 amino acids in its carboxyl-terminal part. Therefore, our results suggest that the major part of the stimulating activity is associated with the amino-terminal part of MSPB, most likely with its lipid moiety. 相似文献
70.
Screw Loosening and Pelvic Canal Narrowing After Lateral Plating of Feline Ilial Fractures With Locking and Nonlocking Plates
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