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341.
Dubé C Ribble C Kelton D 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(11):1254-1260
Data pertaining to the movement of dairy cattle through 2 large livestock markets in the province of Ontario were collected for 1 week per month throughout 2004. Counts and postal codes of sellers and buyers of adult dairy cattle, veal calves, and dairy calves were obtained. Three assumptions were made to represent the level of mixing among animals that could take place at the markets. We estimated the number of livestock holdings that could be exposed to a highly contagious disease agent, should infected animals have been sold through the market in the same week. The estimates ranged from 8 to 20 holdings, when assuming no mixing at the market, to 51 to 171 holdings when assuming complete mixing. These markets are important hubs in the dairy cattle movement network in Ontario and pose the risk of infecting a large number of livestock holdings should animals infected with a highly contagious disease agent pass through them. 相似文献
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343.
Ditte Green-Petersen Charlotte Jacobsen Caroline P. Baron Ivar Lund Henrik Hauch Nielsen 《Journal Of Aquatic Food Product Technology》2013,22(4):333-346
The influence of dietary protein and lipid sources on the quality of organic rainbow trout (Oncorhynchus mykiss) was studied. The protein and oil sources were fishmeal, fish oil, and organic vegetable protein and oils. Sensory profiling was performed during 3 to 14 days of ice storage along with lipid analyses of the fillet. Overall, the results showed that the sensory characteristics of the trout were affected in different ways during ice storage. The source of lipid seemed to affect the sensory quality at the beginning of the storage period, while the protein source seemed to have a more pronounced impact at the end of the storage period. 相似文献
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345.
Host genetic resistance to root‐knot nematodes,Meloidogyne spp., in Solanaceae: from genes to the field 下载免费PDF全文
Arnaud Barbary Caroline Djian‐Caporalino Alain Palloix Philippe Castagnone‐Sereno 《Pest management science》2015,71(12):1591-1598
Root‐knot nematodes (RKNs) heavily damage most solanaceous crops worldwide. Fortunately, major resistance genes are available in a number of plant species, and their use provides a safe and economically relevant strategy for RKN control. From a structural point of view, these genes often harbour NBS–LRR motifs (i.e. a nucleotide binding site and a leucine rich repeat region near the carboxy terminus) and are organised in syntenic clusters in solanaceous genomes. Their introgression from wild to cultivated plants remains a challenge for breeders, although facilitated by marker‐assisted selection. As shown with other pathosystems, the genetic background into which the resistance genes are introgressed is of prime importance to both the expression of the resistance and its durability, as exemplified by the recent discovery of quantitative trait loci conferring quantitative resistance to RKNs in pepper. The deployment of resistance genes at a large scale may result in the emergence and spread of virulent nematode populations able to overcome them, as already reported in tomato and pepper. Therefore, careful management of the resistance genes available in solanaceous crops is crucial to avoid significant reduction in the duration of RKN genetic control in the field. From that perspective, only rational management combining breeding and cultivation practices will allow the design and implementation of innovative, sustainable crop production systems that protect the resistance genes and maintain their durability. © 2015 Society of Chemical Industry 相似文献
346.
Effect of environmental variability on body condition and recruitment success of Atlantic Mackerel (Scomber scombrus L.) in the Gulf of St. Lawrence 下载免费PDF全文
Stéphane Plourde François Grégoire Caroline Lehoux Peter S. Galbraith Martin Castonguay Marc Ringuette 《Fisheries Oceanography》2015,24(4):347-363
The objective of this study was to assess the effect of environmental variability on the dynamics of the Atlantic mackerel (Scomber scombrus L.) stock in the Gulf of St. Lawrence (GSL). We first described the dominant modes of physical and biological (zooplankton) variability using Principal Components Analyses of 40 variables. Two principal modes of variability were identified, a long‐term mode (15–20 yr) associated with a warming of the GSL and a second mode describing alternating cold and warm periods at a higher frequency (5–10 yr). A strong link between physical forcing and the dynamics of zooplankton species known to be important for mackerel was shown. Second, a set of Generalized Additive Models (GAM) was developed to explore how these environmental variations could influence mackerel condition (Fulton's K) and recruitment success (Rs). Optimal GAMs including variations in abundance, species composition and phenology of key copepods improved model performance by 40–50% relative to those considering only physical environmental conditions. The results are consistent with the match–mismatch hypothesis and illustrate the key role of zooplankton dynamics in modulating variations in mackerel K and Rs. Finally, this study showed that large variations in Rs could be caused by varying environmental conditions independently of the influence of stock biomass. Our results strongly indicate that the effect of environmental variability should be considered in the implementation of an ecosystem‐based approach to Atlantic mackerel stock management. 相似文献
347.
Daub Matthias Hakl Ulrike Maressa Beira Hailu Dehne Heinz-Wilhelm Hallmann Johannes Kiewnick Sebastian Eberlein Caroline Heuer Holger Moos Jan H Paulsen Hans M Westphal Andreas Sturhan Dieter Kiewnick Sebastian Wolf Stefanie Bühlmann Andy Frey Jürg Nuaima Rasha Heuer Holger Westphal Andreas 《植物病害和植物保护杂志》2014,121(4):187-189
Journal of Plant Diseases and Protection - 相似文献
348.
Damien Achard David Francoz Andr�� Desrochers Christiane Girard Caroline Pich�� 《Canadian journal of veterinary research》2012,76(2):81-90
The objective of this study was to evaluate the effect of a single joint lavage with 7.2% or 15% hypertonic saline solutions (HSS) on the tarsocrural joints of healthy calves. The tarsi of 10 calves were randomly lavaged with 7.2% HSS, 15% HSS, or isotonic saline. Synovial fluid samples were collected aseptically on days 1 (before joint lavage), 2, 3, 4, and 8 for complete cytological analysis. Lameness, joint swelling, and pain were recorded daily. Calves were euthanized on day 8 for gross and histological analyses of synovial membranes and articular cartilage. Synovitis was evaluated using a scoring system reflecting inflammatory changes in synovial membranes.Joints irrigated with HSS were more distended and painful compared with isotonic control joints. Swelling decreased consistently in the joints lavaged with 7.2% HSS, whereas it remained unchanged in joints lavaged with 15% HSS. Slight to moderate lameness was observed in the joints lavaged with 15% HSS. In comparison to isotonic saline joints, total protein concentration was significantly increased on day 2 and 3 for the joints lavaged with 7.2% HSS (P ≤ 0.01) and on days 2, 3, and 4 in the joints lavaged with 15% HSS (P ≤ 0.0006). Gross and histological findings revealed that synovitis was more severe in the joints lavaged with 15% HSS but variable in the joints lavaged with 7.2% HSS. No significant differences were observed for the articular cartilage.Fifteen percent HSS is not recommended for joint lavage. Although irrigation with 7.2% HSS may induce a variable synovitis, it was found appropriate for joint lavage. Its effects on septic joints remain undetermined. 相似文献
349.
Caroline Vander Straeten 《国外畜牧学(猪与禽)》2012,32(3)
众所周知维生素是所有动物配方饲料中的重要成分.可您是否能够做到有的放矢,选用合适的维生素呢?
维生素和矿物质的足量供应对于家禽和其他物种都非常关键,这些营养成分可保持机体良好营养状态,加强机体的防御体系以抵抗有害病原体的侵袭. 相似文献
350.