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51.
Carbon balance of afforested peatland in Scotland 总被引:3,自引:0,他引:3
52.
Caton JS Reed JJ Aitken RP Milne JS Borowicz PP Reynolds LP Redmer DA Wallace JM 《Journal of animal science》2009,87(1):222-235
Peripubertal ewe lambs (44.3 +/- 1.1 kg of initial BW) were used in a 2 x 3 factorial design to test the effects of plane of nutrition (diet) and stage of gestation on maternal visceral tissue mass, intestinal cellularity, crypt cell proliferation, and jejunal mucosal vascularity. Singleton pregnancies to a single sire were established by embryo transfer, and thereafter ewes were offered a control (Control) or high (High) amount of a complete diet (2.84 Mcal/kg and 15.9% CP; DM basis) to promote slow or rapid maternal growth rates. After d 90 of gestation, feed intake of the Control group was adjusted weekly to maintain BCS and meet the increasing nutrient demands of the gravid uterus. Ewes were slaughtered at 50 d (n = 6 Control; n = 5 High), 90 d (n = 8 Control; n = 6 High), or 130 d (n = 8 Control; n = 6 High) of gestation. Ewes were eviscerated and masses of individual organs were recorded. The jejunum was sampled and processed for subsequent analyses. Final ewe BW for Control-fed ewes was similar at d 50 and 90 and increased (P = 0.10) from d 90 to 130 (46.0, 48.9, and 58.2 +/- 1.6 kg, respectively), whereas final BW increased (P 相似文献
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54.
Serological detection of Citrus psorosis virus (CPsV) by direct tissue blot immunoassay (DTBIA) and by double (DAS) and triple (TAS) antibody sandwich ELISA, was compared in samples from various citrus varieties growing in the glasshouse and in the field. In young shoots and leaves, CPsV was readily detected by the three procedures, whereas DTBIA detection in old leaves was less consistent. DTBIA detection and ELISA readings in nine different citrus varieties were similar, suggesting that CPsV accumulates to equivalent levels in all of them. In infected field trees from Spain or Italy, CPsV was consistently detected by TAS ELISA, even in samples of old leaves in winter, whereas DTBIA detection in the same trees was reliable only when using young shoots. Detection of CPsV by DTBIA and by DAS and TAS ELISA in previously untested field trees correlated perfectly with psorosis diagnostics based on biological indexing, specifically with the capacity of those sources to cross-protect against challenge inoculation with psorosis B. Some trees without bark scaling were shown to be psorosis-infected by biological indexing and to contain CPsV by serological tests; other trees showing psorosis-like bark or leaf symptoms in the field were shown to be psorosis-free by biological indexing and also CPsV-free by serology. This is the first time that the presence of CPsV has been correlated with psorosis infection as diagnosed by biological indexing. 相似文献
55.
We present a simulation model which explicitly captures the movement of wild animals over the landscape and the effect which herd mobility has on the temporal and spatial course of an epidemic. Using the example of classical swine fever in feral pig populations in the tropical savannas, we demonstrate that seasonal factors influencing population density and movement patterns are an important factor in the transmission of the disease. Pig population density is much greater at the start of the dry season than at the start of the wet season, with an epidemic most likely to occur if initiated at the start of the dry season. Spatial heterogeneity due to scarcity of water in the dry season causes herds to congregate around water sources. This concentration of herds, and the consequential isolation of sub-populations, reduces overall disease transmission compared with a model where the population is more evenly distributed over the landscape. The presence of adult male pig herds, which travel over greater distances than family herds, is shown to increase the overall scale of an outbreak in the dry season by connecting together otherwise isolated family herds. Eradication strategies are more likely to be successful in the dry season if they target long-range adult male herds. Our simulation method is generic and is equally applicable to other diseases where the host species is mobile. 相似文献
56.
Objectives : To investigate the use of platelet volume indices in the interpretation of thrombocytopenia in dogs with systemic disease. Methods : Case records of 80 control dogs and 159 thrombocytopenic dogs with systemic disease were reviewed retrospectively. The relationships between mean platelet volume, platelet distribution width and platelet count in systemically well dogs were established. Knowledge of these relationships was used to interpret thrombocytopenia in terms of the underlying disease process. Results : There was a positive relationship between platelet distribution width and mean platelet volume. Both platelet distribution width and mean platelet volume varied in a negative relationship with platelet count, which was unaffected by signalment, underlying disease, variations in haematological parameters or serum proteins. Clinical Significance : The interpretation of mean platelet volume and platelet distribution width in dogs requires simultaneous reference to the platelet count. Platelet volume indices did not aid interpretation of thrombocytopenia in terms of underlying pathological processes in the population studied. 相似文献
57.
Effects of respacing on young Sitka spruce crops 总被引:1,自引:0,他引:1
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59.
A S Turner D W Milne R B Hohn G P Rouse 《Journal of the American Veterinary Medical Association》1979,175(11):1198-1202
Fracture of the capital femoral epiphysis occurred in three foals. One fracture was repaired by means of pinning under radiographic control and the two other fractures were repaired by means of trochanteric osteotomy. 相似文献
60.
Use of the embryonating egg in studies on Marek's disease 总被引:2,自引:0,他引:2