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41.
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D R Ellis 《Equine veterinary journal》1985,17(1):63-65
43.
A Ridden Horse Pain Ethogram (RHpE) was previously developed to facilitate the detection of musculoskeletal pain. The objectives were to apply the RHpE during warm-up for the dressage phase of two 5* three-day events and to correlate the RHpE scores with subsequent performance. It was hypothesised that there would be a higher rate of failure to complete the cross-country phase in horses which exhibited ≥7 behaviours compared with those showing <7 behaviours. The RHpE, comprising 24 behaviours, was applied for 10–12 min during warm-up. Gait abnormalities in trot and canter were recorded. Dressage penalties, cross-country performance, showjumping penalties and final placings were documented. Horses were categorised as those which completed cross-country, or those which did not complete because of elimination or retirement. RHpE scores (n = 137) ranged from 0 to 9/24 (median 3 [range 0–9] for nonlame horses; median 5 [range 1–9] for horses with gait abnormalities in trot or canter). There was a moderate correlation between dressage penalty scores and the RHpE score (rho = 0.4, P<0.001, Spearman rank). Fifty-nine per cent of horses (n = 10/17) with a RHpE score ≥7 failed to complete cross-country, compared with 33% (n = 39/117) with a score <7. Horses that failed to complete the cross-country phase had higher RHpE scores compared with those that completed (P = 0.04, W = 8.3, Kruskal–Wallis; pairwise comparison Bonferroni, P = 0.06). There was a significant (rho = 0.3) relationship between total RHpE score and final horse placings (n = 80, P<0.01, Spearman rank). Horses with lameness or gait abnormalities in canter had significantly higher RHpE scores (P<0.01, χ2 = 35, chi-square test) compared with other horses. There was a strong correlation between the RHpE scores for horses which competed at both events (P<0.001, rho = 0.6, Spearman rank). The RHpE should facilitate earlier identification of horses which may benefit from diagnosis and treatment, resulting in improvement in both performance and equine welfare. 相似文献
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Chunjie LI Thomas W. KUYPER Wopke VAN DER WERF Junling ZHANG Haigang LI Fusuo ZHANG Ellis HOFLLAND 《土壤圈》2022,32(2):317-329
Plant species have different traits for mobilizing sparingly soluble phosphorus (P) resources, which could potentially lead to overyielding in P uptake by plant species mixtures compared to monocultures due to higher P uptake as a result of resource (P) partitioning and facilitation. However, there is circumstantial evidence at best for overyielding as a result of these mechanisms. Overyielding (the outcome) is easily confused with underlying mechanisms because of unclear definitions. We aimed to define a conceptual framework to separate outcome from underlying mechanisms and test it for facilitation and complementarity with respect to P acquisition by three plant species combinations grown on four soils. Our conceptual framework describes both mechanisms of complementarity and facilitation and outcomes (overyielding of mixtures or no overyielding) depending on the competitive ability of the species to uptake the mobilized P. Millet/chickpea mixtures were grown in pots on two calcareous soils mixed with calcium-bound P (CaP) and phytate P (PhyP). Cabbage/faba bean mixtures were grown on both acid and neutral soils mixed with P-coated iron (hydr)oxide (FeP) and PhyP. Wheat/maize mixtures were grown on all four soils. Rhizosphere carboxylate concentration and acid phosphatase activity (mechanisms) as well as plant P uptake and biomass (outcome) were determined for monocultures rhizosphere and species mixtures. Facilitation of P uptake occurred in millet/chickpea mixtures on one calcareous soil. We found no indications for P acquisition from different P sources, neither in millet/chickpea, nor in cabbage/faba bean mixtures. Cabbage and faba bean on the neutral soil differed in rhizosphere acid phosphatase activity and carboxylate concentration, but showed no overyielding. Wheat and maize, with similar root exudates, showed overyielding (the observed P uptake being 22% higher than the expected P uptake) on one calcareous soil. We concluded that although differences in plant physiological traits (root exudates) provide necessary conditions for complementarity and facilitation with respect to P uptake from different P sources, they do not necessarily result in increased P uptake by species mixtures, because of the relative competitive ability of the mixed species. 相似文献
46.
Bovine mononuclear phagocytic cells: identification by monoclonal antibodies and analysis of functional properties 总被引:3,自引:0,他引:3
J A Ellis W I Morrison B M Goddeeris D L Emery 《Veterinary immunology and immunopathology》1987,17(1-4):125-134
Monoclonal antibodies (mAb) which react with bovine monocytes have been produced. These include three mAb (P8, IL-A22 and IL-A24) that recognize the majority of monocytes and granulocytes in peripheral blood; two of these mAb were also shown to react with 30-40% of cells in bone marrow, including both monocytic and granulocytic cells, and with variable percentages of tissue macrophages. Thus these mAb can act as markers for myeloid cells in haemopoietic tissues and for monocytes in cell populations devoid of granulocytes. A further two mAb (IL-A23 and IL-A25) recognize monocytes and/or macrophages. The reactivity of one of these mAb (IL-A25) appears to be mainly restricted to pulmonary macrophages. The other mAb reacts with a variable proportion of blood monocytes and generally with a higher percentage of tissue macrophages, suggesting that its expression may relate to activation or maturation of monocytes. In order to study the functional properties of peripheral blood monocytes, techniques were developed for obtaining populations of peripheral blood mononuclear cells (PBM) depleted of monocytes to less than 0.2% and monocyte populations of greater than 97% purity. Removal of monocytes from PBM abrogated the capacity of the cells to proliferate in response to Con A and PBS, although addition of 2-mercaptoethanol to the cultures restored proliferation. In both allogeneic and autologous mixed leukocyte cultures (MLC), monocytes were required in the stimulator cell populations for induction of the proliferative responses, and both responses could be elicited with purified monocytes. However, proliferation in the autologous MLC occurred only with responder cell populations that were depleted of monocytes. Moreover, it was shown that addition of more than 5% unirradiated monocytes to the autologous MLC suppressed proliferation. These findings indicate that monocytes play an important role in the induction and regulation of cellular immune responses in cattle. Two of the mAb that react with monocytes and granulocytes were tested for their capacity to inhibit proliferative responses of PBM to mitogens, alloantigens or the soluble antigen, KLH.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
47.
Differential antibody responses to Corynebacterium pseudotuberculosis in sheep with naturally acquired caseous lymphadenitis 总被引:1,自引:0,他引:1
J A Ellis D A Hawk L D Holler K W Mills D L Pratt 《Journal of the American Veterinary Medical Association》1990,196(10):1609-1613
Enzyme-linked immunosorbent assays (ELISA) with Corynebacterium pseudotuberculosis cell wall and bacteria-free supernatant with exotoxin preparations as antigens, and hemolysis inhibition tests were used to detect antibodies in the sera of adult range sheep with naturally acquired caseous lymphadenitis (CL). The extent and severity of lesions were quantitated on the basis of a lesion score, derived from an examination of the carcass (peripheral lymphoid tissue) and viscera (including internal lymphoid tissue) at the time of slaughter. The overall prevalence of C pseudotuberculosis-positive CL lesions in 104 sheep was 31.7%. The cell wall ELISA detected antibodies in 96.9% (32/33) of sheep with C pseudotuberculosis-positive CL lesions. The exotoxin ELISA detected antibodies in 84.8% (28/33) of positive sheep in the same group. Both ELISA resulted in a high number of apparent false-positives, with 64.7% and 49.2%, respectively, positive optical density (OD) values in sheep with no gross CL lesions and no apparent C pseudotuberculosis infection. There was no significant relationship between the extent of lesion development (lesion score) and OD values in both cell wall (r = 0.472) and exotoxin (r = 0.464) ELISA. Similarly, there was no significant relationship between the titer of antitoxin antibodies, as measured by the hemolysis inhibition test, and the extent of disease. These investigations indicate that those ELISA that use crude C pseudotuberculosis antigens are of questionable utility in the field, where C pseudotuberculosis infection is endemic in many sheep populations. Furthermore, these studies suggest that antibodies that are reactive with components of C pseudotuberculosis and that develop in response to infection may have little impact on the recovery of the host. 相似文献
48.
Variation for grain milling energy in Hordeum vulgare is associated with differences in grain size, shape and composition. Genetic polymorphisms within and between populations were found across the ecogeographical range of Hordeum spontaneum in Israel. Low milling energy estimates were positively correlated with and predictable by the aridity index. Milling energy in H. spontaneum, collected in Israel, ranged from the lowest values seen in making barley to twice the highest values seen in feed cultivars. It is concluded that H. spontaneum elite genotypes could be effectively identified by milling energy for use in the breeding of new cultivars. 相似文献
49.
Clinical and immunologic response of cattle to administration of a vaccine containing modified-live bovine respiratory syncytial virus 总被引:1,自引:0,他引:1
J A Ellis W C Davis L Talens D L Pratt 《Journal of the American Veterinary Medical Association》1990,196(4):583-589
Healthy yearling beef and dairy cattle were inoculated with a vaccine containing modified-live bovine respiratory syncytial virus (ML-BRSV), and sequential changes in clinical signs of disease, blood leukocyte subsets, BRSV-specific antibody titer, and in vitro lymphocyte blastogenic responses were monitored. Vaccination with ML-BRSV did not cause pyrexia, local or systemic hypersensitivity reaction, or respiratory tract disease. Episodes of leukopenia, abnormalities in lymphocyte subsets, or depression of phytomitogen-induced blastogenic responses were not observed subsequent to vaccination. Exposure to ML-BRSV resulted in at least a 16-fold increase in serum neutralizing antibody titer, with no increase seen in nonvaccinated contact controls. Significant BRSV-specific lymphocyte blastogenic responses were not detected, using one dose of several BRSV antigen preparations in a whole blood culturing system. 相似文献
50.