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81.
High concentrations of the mycotoxins HT-2 and T-2 (HT2?+?T2), primarily produced by Fusarium langsethiae, have occasionally been detected in Norwegian oat grains. In this study, we identified weather variables influencing accumulation of HT2?+?T2 in Norwegian oat grains. Oat grain samples from farmers’ fields were collected together with weather data (2004–2013). Spearman rank correlation coefficients were calculated between the HT2?+?T2 contamination in oats at harvest and a range of weather summarisations within estimated phenological windows of growth stages in oats (tillering, flowering etc.). Furthermore, we developed a mathematical model to predict the risk of HT2?+?T2 in oat grains. Our data show that adequate predictions of the risk of HT2?+?T2 in oat grains at harvest can be achieved, based upon weather data observed during the growing season. Humid and cool conditions, in addition to moderate temperatures during booting, were associated with increased HT2?+?T2 accumulation in harvested oat grains, whereas warm and humid weather during stem elongation and inflorescence emergence, or cool weather and absence of rain during booting reduced the risk of HT2?+?T2 accumulation. Warm and humid weather immediately after flowering increased the risk, while moderate to warm temperatures and absence of rain during dough development, reduced the risk of HT2?+?T2 accumulation in oat grains. Our data indicated that HT2?+?T2 contamination in oats is influenced by weather conditions both pre- and post-flowering. These findings are in contrast with a previous study examining the risk of deoxynivalenol contamination in oat reporting that toxin accumulation was mostly influenced by weather conditions from flowering onwards.  相似文献   
82.
Anticoagulant rodenticides (ARs) are considered inhumane, show increasingly limited efficacy due to acquired resistance, and carry environmental consequences associated with non-target species uptake. In a questionnaire study of 499 UK farms that all deployed chemical rodenticide we found a high mean reliance (79%), on second generation ARs with just over half of the respondents using no other rodent control methods. Additional methods where deployed, alone or in combination, included predation (41%), kill-trap deployment (16%) and shooting (1%). Nearly 40% of all respondents deployed rodenticides year-round. There was no evidence to suggest that “tidy-farm” measures, such as clearing food spills and minimising on-farm rodent harbourage sites aimed at minimising rodent-associated problems, were associated with a lower likelihood of year-round deployment; in fact trends in our analyses suggested the opposite. We therefore encourage operators to fully evaluate the true necessity of rodenticide deployment before AR use.  相似文献   
83.
Microbial communities in soils provide numerous functions vital to agricultural productivity, and there is growing interest in understanding and manipulating these communities to achieve more sustainable production systems. We investigated microbial communities in potato fields in Wisconsin to determine the extent to which microbial communities were structured by inherent soil properties versus factors under grower control. We found that soil properties, including texture and chemistry, shaped microbial communities at broad levels, determining the diversity and abundance of phyla. Organic versus conventional management, however, correlated with finer scale differences in microbial communities, while crop variety was not associated with microbial community composition in this study. These results suggest that grower practices have the potential to alter microbial communities, but these effects will take place within an existing soil context. Future research is necessary to determine how these patterns in microbial community structure relate to functional outcomes for plant health.  相似文献   
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85.
Vernalization insensitivity is a key feature of domesticated chickpea, and its genetic basis is not well understood. We studied vernalization response among hybrid progeny derived from two domesticated × wild crosses. The wild parents are vernalization‐sensitive, late‐flowering genotypes while both domesticated parents are vernalization insensitive. Parental lines and hybrid progeny were tested with (28 days at 4°C) and without vernalization (control). The difference in mean days to flower (?DTF) between control and vernalization treatments was used to assess the flowering vernalization response. A wide range of ?DTF values was observed among the hybrid progeny. Strong genotype by environment interaction effect on ?DTF was observed for the parental accessions and hybrid progeny. We used the ?DTF values to select vernalization responsive and non‐responsive progeny lines. However, the genotype × environment interaction strongly interfered with our selection. Chickpea breeders interested in using the wild progenitor as a donor of exotic traits should be aware of the possibility of introducing vernalization response alleles that may alter the phenology of their breeding materials in an unpredictable manner.  相似文献   
86.
Bottom trawling (nets towed along the seabed) spread around the British Isles from the 1820s, yet the collection of national fisheries statistics did not begin until 1886. Consequently, analysis of the impacts of trawling on fish stocks and habitats during this early period is difficult, yet without this information, we risk underestimating the extent of changes that have occurred as a result of trawling activities. We examined witness testimonies recorded during two Royal Commissions of Enquiry (1863–66 and 1883–85). These enquiries interviewed hundreds of fishers about the early effects of sail trawling and the changes they were witnessing to fish stocks, habitats and fishing practises during this time. We converted all quantitative statements of perceived change in fish stocks and fishing practices to relative change. Witnesses from the north‐east of England interviewed during 1863 revealed an average perceived decline in whitefish of 64% during their careers, which many blamed upon trawling. Between 1867 and 1892, trawl‐landing records from the same location suggest that this trajectory continued, with fish availability declining by 66% during the period. Fishers adapted to these declines by increasing distances travelled to fishing grounds and increasing gear size and quantity. However, inshore declines continued and by the early 1880s even trawl owners were calling for closures of territorial waters to trawling in order to protect fish nursery and spawning grounds. Until now, these testimonies have been largely forgotten, yet they reveal that alterations to near‐shore habitats as a result of trawling began long before official data collection was initiated.  相似文献   
87.
In this paper, we analyzed a very large field data set on intramammary infections (IMI) and the associated somatic cell count (SCC) in dairy cows. The objective of the study was to analyze the impact of coagulase-negative staphylococci (CNS) IMI on cow SCC, both mean and variability, and on the potential of these infections to have a major impact on the bulk milk SCC (BMSCC). Data and milk samples for bacterial culture were collected by Quality Milk Production Services (QMPS) between 1992 and March of 2007. The QMPS program services dairy farms in New York State and other states in the Northeastern USA and operates in conjunction with Cornell University. Only records from cows where SCC and milk production data were available, and where only one organism was isolated from bacterial cultures of milk samples (or where culture was negative) were used for this analysis. A total of 352,614 records from 4200 whole herd mastitis screening sampling qualified for this study. Within herds an average of 15% (S.D. 12%) of cows sampled were infected with CNS, ranging between 0 and 100%. Average within herd prevalence of cows with a CNS IMI and an SCC over 200,000 cells/ml was 2% (S.D. 4%) with a minimum of 0% and a maximum of 50%. Results of linear mixed models showed three distinct populations of IMI statuses: negative cultures with the lowest SCC; CNS and Corynebacterium bovis with a moderate increase in SCC, and Streptococcus agalactiae, Streptococcus spp. and Staphylococcus aureus showing an important increase in SCC. Surprisingly, milk production was slightly but significantly higher in CNS infected cows compared to culture-negative cows, whereas it was strongly reduced in cows with a major pathogen IMI. The percentage contribution of CNS infections to the BMSCC was 17.9% in herds with a BMSCC less than 200,000 cells/ml. This value decreased to 11.9 and 7.9% in herds with bulk milk SCC between 200,000 and 400,000 and over 400,000 cells/ml, respectively. We concluded that very few herds with milk quality problems would have an important increase in BMSCC that could be mostly attributed to CNS infections. On the other hand, in herds with low BMSCC, CNS infections may be an important contributor to the total number of somatic cells in the bulk milk.  相似文献   
88.
Background: Guinea pigs (Cavia porcellus) are often presented as patients in veterinary practice. Nevertheless, only limited information is available about endocrine diseases or thyroxine reference values for the species. Objective: The aim of this study was to determine serum thyroxine concentrations in a well‐defined population of clinically healthy pet guinea pigs. Methods: Between October 2007 and July 2008, serum samples were collected from 40 clinically healthy guinea pigs of different sexes, ages, and breeds that were presented to our clinic for a general health check or for castration. Pregnant females were excluded from the study. Thyroxine concentration was measured using a chemiluminescence test (Immulite 2000 Canine Total T4). Results: Thyroxine concentrations ranged from 14.2 to 66.9 nmol/L (1.1–5.2 μg/dL) with a median value of 27.0 nmol/L (2.1 μg/dL). Females (n=16) had significantly (P=.039; Mann–Whitney U‐test) lower thyroxine values than castrated males (n=8), whereas no differences were found between females and intact males (n=16) or between intact and castrated males. No significant correlation was found between thyroxine concentration and age. Conclusion: This is the first report of serum thyroxine reference values for a well‐defined population of healthy pet guinea pigs as measured by a chemiluminescence assay. The results were higher than those previously reported for this species and emphasize the importance of using appropriate reference intervals for the diagnosis of hyperthyroidism.  相似文献   
89.
Arrowsmith is a unique computer-assisted strategy designed to assist investigators in detecting biologically-relevant connections between two disparate sets of articles in Medline. This paper describes how an inter-institutional consortium of neuroscientists used the UIC Arrowsmith web interface http://arrowsmith.psych.uic.edu in their daily work and guided the development, refinement and expansion of the system into a suite of tools intended for use by the wider scientific community.  相似文献   
90.
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