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S.J. Ruff BS C.H. Wood PhD D.K. Aaron PhD L.M. Lawrence PhD 《Journal of Equine Veterinary Science》1993,13(10)
The objectives of this study were to compare the growth rates of normal thoroughbred foals to previously reported growth rates1 and to compare growth rates of normal foals with foals diagnosed with cervical vertebral malformation (CVM). Fifty-six foals from two foals crops were used, and eight of these foals were diagnosed with CVM. Growth rate analysis of the CVM foals had to be restricted to the period prior to diagnosis because once these foals were diagnosed, they were treated differently from the normal foals. Body measurements taken at 7 day intervals were body weight, wither height, hip height, and heart girth. For statistical analysis, data were broken down into 30 day intervals. Results showed that the growth rates for normal thoroughbred foals have not changed in the past fifteen years. The CVM foals tended to be heavier and taller during some time intervals than the normal foals, but there were no significant differences between the two groups in any of the skeletal growth measurements. Body weight gain was faster in CVM foals from 31–60 d (p<.01), 121–150 d (p<.01), and 211–240 d (P –.05). 相似文献
33.
In the goat, diagnosis of copper (Cu) deficiency is often based on measurement of Cu in serum or plasma. Previous research in cattle and sheep has shown that these values are not interchangeable, but data for goats have not been published. Paired serum and heparinised plasma samples taken from 119 goats in eight herds were tested for Cu concentration. Plasma and serum Cu were significantly correlated (r=0.95). On average serum Cu was 3.5 μmol/L lower than plasma Cu, but this difference was related to Cu status (r=0.45). Mean serum Cu concentration was 83% of plasma Cu, with the 95% limits of agreement ranging from 66% to 100%. Similar to cattle and sheep, individual variability in Cu loss during clotting is too great for serum Cu to be used as a measure of Cu status in goats. 相似文献
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Deanna L. Funnell Christopher B. Lawrence Jeffrey F. Pedersen Christopher L. Schardl 《Physiological and Molecular Plant Pathology》2004,65(6):285-296
Systemic acquired resistance (SAR) is induced following inoculation of Peronospora tabacina sporangia into the stems of Nicotiana tabacum plants highly susceptible to the pathogen. Previous results have shown that accumulation of acidic β-1,3-glucanases (PR-2's) following induction of SAR by P. tabacina may contribute to resistance to P. tabacina. We showed that up-regulation of the PR-2 gene, PR-2d, following stem inoculation with P. tabacina, is associated with SAR. Studies using plants transformed with GUS constructs containing the full length promoter from PR-2d or promoter deletions, provided evidence that a previously characterized regulatory element that is involved in response to salicylic acid (SA), may be involved in regulation of PR-2d following induction of SAR with P. tabacina. This work provides evidence that regulation of PR-2 genes during P. tabacina-induced SAR may be similar to regulation of these genes during infection of N-gene tobacco by TMV or following exogenous application of SA, and provides further support for the role of SA in regulation of genes during P. tabacina-induced SAR. 相似文献
37.
The influence of regulatory forest policy tools on biodiversity measures for forests in Ukraine 总被引:1,自引:0,他引:1
The transition from a state-oriented forest economy to a market-oriented one requires a critical analysis of the set of tools designed to implement state forest policies. One of the important goals of Ukrainian forest policy is conservation of the biodiversity of forest ecosystems. This paper analyzes the influence of two of the regulatory forest policy instruments (zoning and prohibition of final harvesting) on the diversity of woody vegetation using Tobit regression. Data on the forest resources of the Sumy administrative province in Ukraine are used for the analysis. Additionally, we look at how diversity of woody vegetation is affected by the form of forest tenure. 相似文献
38.
Joe M. Fox Addison L. Lawrence Eunice Li‐Chan 《Journal of the World Aquaculture Society》2009,40(2):171-181
Tail muscle tissue free amino acids (FAA) concentration is reported for subadult (4.3 g) Litopenaeus vannamei fed diets containing only protein‐bound amino acids, crystalline lysine as a supplement to protein‐bound lysine, and only crystalline amino acids (CAA). FAA were determined in shrimp at 0.00, 0.25, 0.5, 1, 2, 4, and 8 h postfeeding. Highest total tissue concentrations of essential amino acids and individual amino acids were typically observed 4 h postfeeding for shrimp fed intact and crystalline lysine‐supplemented feeds. Those shrimp offered diets containing only CAA showed no tissue maxima. Similar uptake patterns for lysine shown by shrimp fed the intact and crystalline lysine‐supplemented diet indicate the potential use of small amounts of crystalline lysine in shrimp feeds. 相似文献
39.
Lawrence W. C. Lai K. W. Chau S. K. Wong N. Matsuda Frank T. Lorne 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3):289-316
ABSTRACT From a transaction cost perspective, this paper shows how the tradition of consuming marine fish by the majority of Hong Kong's Chinese citizens has shaped the means and modes of marketing seafood in Hong Kong. It is argued that consumer preferences stimulate aquaculture as a non-open access measure to bypass state fish marketing regulations. This has resulted in two outcomes. First, the transaction cost savings on metering output quantity and quality under private property have led not only to the collapse of the state monopoly on marine fish marketing, but also to the emergence of the (then new but) currently popular kind of Chinese seafood restaurant in Hong Kong. Second, consumer preferences for variety have shaped the form of coordination between the producer and the consumer. The advantage of market coordination has led to the emergence of a system of wholesaling and retailing rather than vertical integration. Issues concerning the emergence of Hong Kong as a regional live marine fish production and trading centre are discussed in terms of the contribution of local mariculture to sustainable development. 相似文献
40.
Tapasya Babu Wooiklee Paye Yumiko Kanke Lawrence Datnoff 《Communications in Soil Science and Plant Analysis》2016,47(12):1578-1597
Calibration of crop responses to applied silicon (Si) serves as a basis for developing Si fertilizer recommendation guidelines. A greenhouse experiment was set up in a randomized complete block design with five replications, two sources of Si (wollastonite and slag) and four Si rates (0, 170, 340 and 680 kg ha?1) to calibrate plant-available Si for growing rice in Louisiana soils. Silicon concentrations were determined in soils using seven different extraction procedures. Based on a quadratic model (p < 0.05), the estimated soil Si critical level using 0.01 M calcium chloride (CaCl2) for Sharkey clay soil was 110 mg kg?1 while for Crowley silt loam and Commerce silt loam, levels were 37 and 43 mg kg?1, respectively. These results suggest that suitability of an extractant that gives the best estimate of plant-available Si could considerably depend on soil type and it is unlikely that there is a universal extractant for all soils. 相似文献