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排序方式: 共有450条查询结果,搜索用时 15 毫秒
411.
412.
Kenneth D Newman Denis Harvey Jean-Philippe Roy 《Veterinary Clinics of North America: Food Animal Practice》2008,24(2):359-82, viii
To reduce the potential drawbacks associated with laparotomy techniques for correction and fixation of left displaced abomasums (LDA), minimally invasive techniques have been developed. This chapter reviews the toggle pin suture (TPS) and the laparoscopic abomasopexy procedures used in the field for correction and fixation of the abomasum for correction of left-displacement of the abomasum in dairy cows. The importance of case selection cannot be overestimated. By combining laparoscopy with the principle of the TPS procedure, the lack of visual control associated with the TPS procedure is eliminated, while the advantage of the speed of completion and minimal invasiveness provided by both procedures are maintained. Successful LDA treatment includes not only early detection and treatment of the LDA, but also the prevention of secondary ketosis and aggressive treatment of concurrent disease. 相似文献
413.
S Ben Jemaa S Fritz F Guillaume T Druet C Denis A Eggen M Gautier 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2008,125(4):280-288
The purpose of this study was to map quantitative trait loci (QTL) influencing female fertility estimated by non-return rate (NRR) in the French dairy cattle breeds Prim'Holstein, Normande and Montbeliarde. The first step was a QTL detection study on NRR at 281 days after artificial insemination on 78 half-sib families including 4993 progeny tested bulls. In Prim'Holstein, three QTL were identified on Bos taurus chromosomes BTA01, BTA02 and BTA03 (p < 0.01), whereas one QTL was identified in Normande on BTA01 (p < 0.05). The second step aimed at confirming these three QTL and refining their location by selecting and genotyping additional microsatellite markers on a sub-sample of 41 families from the three breeds using NRR within 56, 90 and 281 days after AI. Only the three QTL initially detected in Prim'Holstein were confirmed. Moreover, the analysis of NRR within 56, 90 and 281 days after AI allowed us to distinguish two FF QTL on BTA02 in Prim'Holstein, one for NRR56 and one for NRR90. Estimated QTL variance was 18%, 14%, 11.5% and 14% of the total genetic variance, respectively, for QTL mapping to BTA01, BTA02 (NRR90 and NRR56) and BTA03. 相似文献
414.
415.
Justus Masa John Herbert Muyonga Justus Kwetegyeka Vincent Makokha Denis Ocen 《Journal Of Aquatic Food Product Technology》2013,22(1):64-72
Fish oils may differ in fatty acid (FA) composition depending on diet. Oils extracted from muscle, liver, and adipose tissue of Nile perch (Lates niloticus), Nile tilapia (Oreochromis niloticus), silver fish (Rastrineobola argentea), lungfish (Protopterus aethiopicus), Victoria squeaker (Synodontis victoriae), and two catfishes (Clarias gariepinus and Bagrus docmac) from Lake Victoria, a tropical freshwater lake, were evaluated for FA composition. Oil contents of muscles, livers, and adipose tissues were in the range of 3.16 to 13.8%, 3.62 to 53.4%, and 28.8 to 42.4%, respectively. Omega-3 polyunsaturated FA, particularly alpha-linolenic (ALA), eicosapentaenoic (EPA), docosapentaenoic (DPA), and docosahexaenoic (DHA) acids, were found to be in substantial amounts in oils from all seven fish species. Ratios of polyunsaturated FA to saturated FA (0.79 to 1.18) were in the range considered adequate for normal health. Overall, the results show that the fish species studied are a rich source of omega-3 polyunsaturated FA. 相似文献
416.
Improving models of forest nutrient export with equations that predict the nutrient concentration of tree compartments 总被引:1,自引:0,他引:1
Laurent Augusto Céline Meredieu Didier Bert Pierre Trichet Annabel Porté Alexandre Bosc Frédéric Lagane Denis Loustau Sylvain Pellerin Frédéric Danjon Jacques Ranger Jacques Gelpe 《Annals of Forest Science》2008,65(8):808-808
417.
Pons A Lavigne V Landais Y Darriet P Dubourdieu D 《Journal of agricultural and food chemistry》2008,56(5):1606-1610
The enantiomers of sotolon, a flavor compound typical of oxidized white wines, were separated by preparative HPLC to determine their perception thresholds and distribution in wines. The enantiomeric ratios of chiral sotolon were evaluated in several dry white wines using gas chromatography and a chiral column (beta-cyclodextrin) connected to a 2 m precolumn (BP20). The perception threshold of (S)-sotolon (0.8 microg/L) in model wine solution was 100 times lower than that of the (R) form (89 microg/L), indicating that (S)-sotolon contributes to the characteristic aroma of prematurely aged dry white wines. Both enantiomers are detected in white wines. Analysis of commercial dry white wines from various vintages and origins revealed three types of distribution patterns: the racemic form, an excess of R, and an excess of S. The proportions found in these wines may be partially explained by the slow racemization kinetics (20 months) of optically active sotolon. 相似文献
418.
New Forests - In Laos, there are extensive shifting cultivation areas and regrowth forests spontaneously established on fallow lands. The aims of the study were to conduct a comparative study of... 相似文献
419.
Morphological measurements such as head-capsule (HC) width can be very useful and accessible tools that may be employed for classifying Lepidopteran larval instars according to stage of life history. The availability of such measures is crucial in the management of larval pests, because their control relies upon making accurate assessment of the life history stage at which larvae has reached in various environmental conditions. Such forecasts are then used in order to estimate the timing of emergence for future adult populations. Previous studies investigated the use of head-capsule widths from field larvae of European Grapevine Moth (EGVM), Lobesia botrana Den. and Schiff., to describe the distributions of the five instars during three generations of the insect. The observations were performed in 1998 and 2002 in a vineyard near Bordeaux. The results presented here increase the scope of earlier methods by providing statistical confidence. Our method was calibrated on a large number of individuals (N = 552) issued from our insect culture and uses a nonlinear least-squares parameter estimation to describe the distribution of each larval instar inside each generation. The model was tested on a wild larval population (n = 3007) occurring in our experimental vineyard during two complete years. The instar class ranges and boundaries were characterized with the associated probabilities of misclassification. A final classification statistical model is developed for each instar and each generation. From this study, we conclude that larval HC sizes increase statistically according to the generation of the year, and thus is influenced by grape phenology. 相似文献
420.
Sandeep Kumar Tripathi Babloo Sharma R. Ray P. Raha Anjelo Francis Denis 《Communications in Soil Science and Plant Analysis》2018,49(9):995-1008
In India, the production of turmeric is not even half compared to its potential. To analyze the possibilities for higher production in turmeric, this study was conducted at the BCKV, Gayeshpur, West Bengal, during 2011 and 2012, to evaluate the effect of irrigation scheduling (0.6, 0.9, and 1.2 irrigation water (IW)/cumulative pan evaporation (CPE) and rainfed) in main plots and nutrient management [100% inorganic, 75% inorganic + 25% FYM (Farm yard manure), and 50% inorganic + 25% FYM + 25% vermicompost] in subplots on soil moisture depletion and productivity of turmeric. The highest value of fresh rhizome yield (23.90 kg ha?1) and qualitative indices were obtained with irrigation schedule at 0.9 IW/CPE ratio water regimes and 50% inorganic + 25% FYM + 25% vermicompost. The correlation coefficients of water use and yield of turmeric were found at 0.943. The combination of 0.9 IW/CPE and 50% inorganic + 25% FYM + 25% vermicompost improved the overall performance of turmeric crop. 相似文献