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41.
42.
Case-control study to investigate risk factors for horse falls in hurdle racing in England and Wales
Between March 1, 2000 and August 31, 2001, a case-control study was conducted on 12 racecourses in England and Wales to identify and quantify the risk factors associated with horse falls in hurdle races. The cases and controls were defined so that variables relating to the horse, the jockey, the race and racecourse, and the jump could be considered. The cases were defined as a jumping effort at a hurdle flight that resulted in a fall, and the controls were defined as a successful jump over a hurdle at any of the 12 racecourses within 14 days before or after the case fall. Conditional logistic regression was used to examine the univariable and multivariable relationships between the predictor variables and the risk of falling. The risk of falling was significantly associated with the position of the jump in the race, and with the distance and speed of the race. A horse's previous racing experience and history were also significantly associated with the risk of falling and horses participating in their first hurdle race were at almost five times greater risk of falling than horses that had hurdled before. 相似文献
43.
Visser EK Van Reenen CG Rundgren M Zetterqvist M Morgan K Blokhuis HJ 《Equine veterinary journal》2003,35(2):176-183
REASONS FOR PERFORMING STUDY: Behavioural tests as well as observers' ratings have been used to study horses' temperament. However, the relationship between the ratings and the responses in behavioural tests has not yet been studied in detail. OBJECTIVES: The aim of the present study was to examine this relationship between ratings and responses. METHODS: Eighteen mature Swedish Warmblood horses were subjected to 2 behavioural tests, one relating to novelty (novel object test) and one to handling (handling test). Subsequently, 16 of these horses were ridden by 16 equally experienced students, having no former experience with the horses. Immediately after each ride, the students scored the horse for 10 temperamental traits using a line rating method. RESULTS: It was shown that for each temperamental trait all 16 riders agreed on the ranking of the horses (0.212相似文献
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Y. Luo Z. Ma H. C. Reyes D. Morgan T. J. Michailides 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(2):145-154
The fungal pathogen Monilinia fructicola causes blossom blight and fruit brown rot of stone fruits in California. In this study, spore densities in the air were monitored
in six orchard/year combinations with Burkard spore traps. A real-time PCR assay was developed to efficiently quantify the
dynamics of spore density in these orchards during the growing season. Different patterns of dynamics of spore density were
observed in these orchards. A linear relationship between numbers of spores counted with a compound microscope and those determined
with the real-time PCR assay was obtained, using the same samples of spore traps. Spore density in five of six orchard/year
combinations ranged from 0.0 to 0.05 spores l−1, except for that in orchard 4, which showed much higher values of spore density in the air, as well as higher values and
wider range of incidences of blossom infection and fruit rot than those in the other orchards. The results demonstrated a
potential method to quantitatively determine spore inoculum potential in orchards by using a real-time PCR assay. 相似文献
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47.
E.?A.?CatchpoleEmail author Y.?Fan B.?J.?T.?Morgan T.?H.?Clutton-Brock T.?Coulson 《Journal of Agricultural, Biological & Environmental Statistics》2004,9(1):1-26
A detailed and extensive mark-recapture-recovery study of red deer on the island of Rum forms the basis of the modeling of
this article. We analyze male and female deer separately, and report results for both in this article, but use the female
data to demonstrate our modeling approach. We provide a model-selection procedure that allows us to describe the survival
by a combination of age-classes, with common survival within each class, and senility, which is modeled continuously as a
parametric function of age. Dispersal out of the study area is modeled separately. Survival and dispersal probabilities are
examined for the possible influence of both environmental and individual covariates, including a range of alternative measures
of population density. The resulting model is succinct and biologically realistic. We compare and contrast survival rates
of male and female deer of different ages and compare the factors that affect their survival. We demonstrate large differences
in the rate of senescence between males and females even though their senescence begins at the same age. The differences between
the sexes suggest that, in population modeling of sexually size-dimorphic species, it is important to identify sex-specific
survival functions. 相似文献
48.
R W Morgan J Gelb C S Schreurs D Lütticken J K Rosenberger P J Sondermeijer 《Avian diseases》1992,36(4):858-870
Recombinant strains of herpesvirus of turkeys (HVT) were constructed that contain either the fusion protein gene or the hemagglutinin-neuraminidase gene of Newcastle disease virus (NDV) inserted into a nonessential gene of HVT. Expression of the NDV antigens was regulated from a strong promoter element derived from the Rous sarcoma virus long terminal repeat. Recombinant HVT strains were stable and fully infectious in cell culture and in chickens. Chickens receiving a single intra-abdominal inoculation at 1 day of age with recombinant HVT expressing the NDV fusion protein had an immunological response and were protected (> 90%) against lethal intramuscular challenge at 28 days of age with the neurotropic velogenic NDV strain Texas GB. Recombinant HVT expressing the NDV hemagglutinin-neuraminidase provided partial protection (47%) against the same challenge. Chickens vaccinated with recombinant HVT vaccines had low levels of protection against NDV replication in the trachea when challenged ocularly. Recombinant HVT vaccines and the parent HVT strain provided similar levels of protection to chickens challenged with the very virulent RB1B strain of Marek's disease virus, indicating that insertion of foreign sequences into the HVT genome did not compromise the ability of HVT to protect against Marek's disease. 相似文献
49.
BD Gartrell KJ Morgan L Howe JS Munday AMJ McFadden 《New Zealand veterinary journal》2013,61(4):241-243
CASE HISTORY A 21-year-old male sulphur-crested cockatoo (Cacatua galerita) was presented following the sudden appearance of blood associated with the passage of faeces and urates. CLINICAL AND PATHOLOGICAL FINDINGS: There was fresh blood-staining of the feathers around the vent. The dorsal mucosal wall of the proctodeum was erythematous and roughened in appearance. An endoscopic biopsy was performed, and histological examination revealed multiple fronds of epithelium; the mucosa varied from simple to pseudostratified columnar epithelium, with diffuse hyperplasia of goblet cells. The underlying connective tissue stroma was well vascularised and was infiltrated with mixed inflammatory cells, comprising granulocytic cells and macrophages. PCR testing for both herpesvirus and papillomavirus, using consensus primers, was negative. DIAGNOSIS: Cloacal papillomatosis. CLINICAL RELEVANCE: This case manifested typical clinical signs and histological lesions of cloacal papillomatosis in the absence of demonstrable herpesvirus or papillomavirus. Veterinarians need to consider this disease in the differential diagnosis of blood in the droppings of parrots and cockatoos even in countries where psittacine herpesviruses are exotic diseases. 相似文献
50.