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排序方式: 共有182条查询结果,搜索用时 15 毫秒
51.
52.
The aquaculture production of common carp (Cyprinus carpio) is one of the biggest on a global scale, although European production represents a minor part. Thus, common carp is a little-exploited, low-cost, and highly nutritious food source. For development of new quality products that have customers’ appeal and are safe, a combination of traditional and novel technologies can be used. However, good quality raw material is of basic importance for further processing and final product quality. Fish microbiota have a major role in fish spoilage and as potential human pathogens. To diminish the negative impact of the microbiota on fish, different methods and technologies can be used. The important steps before the final product processing in the production of common carp products include purging, transport, pre-slaughter storage, slaughter method, bleeding, cleaning, desliming, descaling, and gutting. The most important factor in fish spoilage prevention is chilling, although to assure longer freshness and shelf-life, the concept of hurdle technology should be used. Many preservation and packaging techniques have been developed for fish products, but not all have been researched for common carp products. This review aims to identify the gaps in research, knowledge, and practice for the microbiological aspects that impact upon the production of high-quality common carp food products. 相似文献
53.
Domingo Casamian-Sorrosal Richard Saunders William Browne Sarah Elliot Sonja Fonfara 《Research in veterinary science》2014
This paper reports radial colour and longitudinal mitral annulus pulsed-wave tissue Doppler findings in a large cohort of healthy, adult pet rabbits. Thirty-nine rabbits (22 Dwarf Lops, 14 French Lops and three Alaskans) underwent conscious echocardiography. The median age of the rabbits was 22 months and the median weight was 2.8 kg (Dwarf Lop 2.4 kg/French Lop 6.0 kg). Adequate radial colour and longitudinal pulsed-wave tissue Doppler traces were obtained in 100% and 85% of cases, respectively. Most systolic tissue Doppler parameters were significantly higher in French Lops than in Dwarf Lops. Separation of mitral inflow diastolic waves was present in 40% of cases using conventional spectral Doppler and in >60% of cases using pulsed-wave tissue Doppler which could be beneficial when evaluating diastolic function in rabbits. This study can be used as a reference for normal echocardiographic tissue Doppler values for adult rabbits undergoing conscious echocardiography in clinical practice. 相似文献
54.
Sonja Hartnack 《Veterinary anaesthesia and analgesia》2014,41(3):227-232
Method comparison studies are needed for validation of new methods of measurements, for example, non‐invasive blood pressure measurements against standard reference methods. After a brief introduction into method comparison studies, this paper is organized in three sections. The first section deals with the widely, though not always appropriately, used classical Bland‐Altman plot with the limits of agreement and its extensions with non‐constant bias and multiple observations. The second section comments on other statistical approaches including correlation coefficients, linear regressions and sensitivities and specificities which are sometimes seen in method comparison studies. The third section proposes the usage of linear mixed effects models as a flexible way to deal with questions associated with method comparison studies. 相似文献
55.
Andrea Schwarz Karin Kalchofner Julia Palm Stephanie Picek Sonja Hartnack Regula Bettschart‐Wolfensberger 《Veterinary anaesthesia and analgesia》2014,41(5):480-490
ObjectiveTo determine the induction doses, then minimum infusion rates of alfaxalone for total intravenous anaesthesia (TIVA), and subsequent, cardiopulmonary effects, recovery characteristics and alfaxalone plasma concentrations in cats undergoing ovariohysterectomy after premedication with butorphanol-acepromazine or butorphanol-medetomidine.Study designProspective randomized blinded clinical study.AnimalsTwenty-eight healthy cats.MethodsCats undergoing ovariohysterectomy were assigned into two groups: together with butorphanol [0.2 mg kg?1 intramuscularly (IM)], group AA (n = 14) received acepromazine (0.1 mg kg?1 IM) and group MA (n = 14) medetomidine (20 μg kg?1 IM). Anaesthesia was induced with alfaxalone to effect [0.2 mg kg?1 intravenously (IV) every 20 seconds], initially maintained with 8 mg kg?1 hour?1 alfaxalone IV and infusion adjusted (±0.5 mg kg?1 hour?1) every five minutes according to alterations in heart rate (HR), respiratory rate (fR), Doppler blood pressure (DBP) and presence of palpebral reflex. Additional alfaxalone boli were administered IV if cats moved/swallowed (0.5 mg kg?1) or if fR >40 breaths minute?1 (0.25 mg kg?1). Venous blood samples were obtained to determine plasma alfaxalone concentrations. Meloxicam (0.2 mg kg?1 IV) was administered postoperatively. Data were analysed using linear mixed models, Chi-squared, Fishers exact and t-tests.ResultsAlfaxalone anaesthesia induction dose (mean ± SD), was lower in group MA (1.87 ± 0.5; group AA: 2.57 ± 0.41 mg kg?1). No cats became apnoeic. Intraoperative bolus requirements and TIVA rates (group AA: 11.62 ± 1.37, group MA: 10.76 ± 0.96 mg kg?1 hour?1) did not differ significantly between groups. Plasma concentrations ranged between 0.69 and 10.76 μg mL?1. In group MA, fR, end-tidal carbon dioxide, temperature and DBP were significantly higher and HR lower.Conclusion and clinical relevanceAlfaxalone TIVA in cats after medetomidine or acepromazine sedation provided suitable anaesthesia with no need for ventilatory support. After these premedications, the authors recommend initial alfaxalone TIVA rates of 10 mg kg?1 hour?1. 相似文献
56.
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
57.
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
58.
59.
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