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711.
Hodgson D Howe S Jeffcott L Reid S Mellor D Higgins A 《Veterinary journal (London, England : 1997)》2005,169(3):322-325
Oral administration of altrenogest for oestrus suppression in competition horses is believed to be widespread in some equestrian disciplines, and can be administered continuously for several months during a competition season. To examine whether altrenogest has any anabolic or other potential performance enhancing properties that may give a horse an unfair advantage, we examined the effect of oral altrenogest (0.044 mg/kg), given daily for a period of eight weeks, on social hierarchy, activity budget, body-mass and body condition score of 12 sedentary mares. It was concluded that prolonged oral administration of altrenogest at recommended dose rate to sedentary mares had no effect on dominance hierarchies, body-mass or condition score. 相似文献
712.
ABSTRACT Agrobacterium vitis is the causal agent of crown gall disease in grapevine, which can be severe in many regions worldwide. Vitis vinifera cultivars are highly susceptible to freeze injury, providing the wounds necessary for infection by A. vitis. Wound position in relation to the uppermost bud of cuttings was determined to be important in tumor development. Inoculated wounds below buds developed tumors, whereas wounds opposite the bud did not, implying that indole-3-aectic acid flow contributes to tumor formation. If auxin was applied to wounds prior to inoculation with a tumorigenic A. vitis strain, all sites of inoculation developed tumors, accompanied by an increased amount of callus in the cambium. Wounds inoculated with an A. vitis biological control strain F2/5 prior to application of the pathogen did not develop galls. A closer examination of these wounds determined that callus cells formed in the cambium during wound healing are susceptible to transformation by the pathogen. Although the mechanism by which F2/5 prevents transformation is unknown, our observations suggest that F2/5 inhibits normal wound healing by inducing necrosis in the cambium. 相似文献
713.
714.
715.
OBJECTIVE: To determine the predictive values, sensitivity and specificity of abdominal fluid variables associated with the need for surgery in horses with an acute abdominal crisis. DESIGN: Retrospective study. ANIMALS: Two-hundred and thirty-six horses examined for signs of abdominal pain between January 1993 and June 1999. METHODS: Breed, age and gender of the horse and colour, total protein concentration and total nucleated cell count of an abdominal fluid sample were recorded. Colour of the abdominal fluid was classified as normal if it was yellow and transparent. Turbid fluid or fluid that was serosanguinous or other colours was classified as abnormal. Protein concentration < or = 20 g/L and a total nucleated cell count < or = 5 x 10(9) cells/L were considered normal and values above these were considered abnormal. An abdominal fluid sample was classified as abnormal if one or more of the three variables were considered abnormal. Cases were defined as surgical when lesions identified at surgery or necropsy examination would not have resolved with medical treatment alone. Cases were defined as medical in horses that survived without surgical intervention, and those with a lesion found at surgery or necropsy that would have resolved with medical treatment alone. A third category was identified during the study as those diagnosed with Actinobacillus equuli--induced peritonitis. These horses were included in the study but not in the data analysis. DATA ANALYSIS: The association between the sensitivity, specificity and positive and negative predictive value of colour, total protein, and total nucleated cell count in the abdominal fluid and the need for surgery was calculated. RESULTS: There were 100 females and 136 males of mixed breeds, ranging from 3 days to 26 years of age that had an abdominocentesis performed during the specified period. There were 97 horses with a lesion classified as surgical, 91 horses with a lesion classified as medical and 48 horses with a diagnosis of A equuli-induced peritonitis. Colour of the abdominal fluid was recorded in all horses, protein concentration was recorded in 194 horses and total nucleated cell count was recorded in 179 horses. Abnormal abdominal fluid colour had a sensitivity, specificity, positive and negative predictive value of 92%, 74%, 79% and 89% respectively, associated with the need for surgery. Sensitivity, specificity, positive and negative predictive values for a serosanguinous abdominal fluid sample associated with the need for surgery were 48%, 99%, 98% and 64% respectively. Abnormal abdominal fluid protein concentration had a sensitivity, specificity, positive and negative predictive value of 86%, 75%, 77% and 85% respectively, associated with the need for surgery. The sensitivity, specificity, positive and negative predictive value associated with the need for surgery in horses with an abnormal total nucleated cell count in the abdominal fluid were 59%, 75%, 67% and 67%, respectively. An abdominal fluid sample classified as abnormal had a sensitivity, specificity, positive and negative predictive value of 92%, 74%, 79% and 89% respectively, associated with the need for surgery. CONCLUSION: Results of this study suggest that abdominal fluid sample analysis contributes to the decision to proceed to surgery, but is not a diagnostic panacea. Colour and protein concentration of abdominal fluid were the most useful variables in abdominal fluid for differentiating medical and surgical lesions. Colour and protein had a greater value in horses with a disease likely to respond to medical treatment (negative predictive value) than those with a lesion requiring surgery (positive predictive value) except when the fluid was serosanguinous. Abdominal fluid colour and protein are clinically relevant and easily measured in the field, providing immediate information without the need for sophisticated laboratory techniques. 相似文献
716.
An outbreak of malignant catarrhal fever (MCF) resulted in the deaths of 12 cattle in a herd of 77 animals during seven weeks in 1999; in addition, one cow developed a milder disease which was confirmed as MCF by PCR for ovine herpesvirus 2 DNA and an immunofluorescent antibody test for antibodies to the virus, but recovered. Further PCR and serological testing revealed the infection in three other animals, none of which developed clinical disease. Hypocuprosis and the possibility of a genetic predisposition were identified as factors which may have contributed to the outbreak. 相似文献
717.
The aim of this study was to investigate whether femoral artery pulsatility index (PI) can be used as an indicator of vasomotor tone in the digit of an ungulate species by measuring the change in PI induced by infusion of vasoactive agents in halothane-anaesthetised sheep. Intra-arterial infusion of the vasoconstrictor phenylephrine (9 microg min(-1)) tended to increase waveform PI (3.89-6.24, n=4, P=0.100). Infusion of a low dose (3 microg min(-1)) of the vasodilator sodium nitroprusside did not alter femoral artery PI, however infusion of a higher dose (30 microg min(-1)) tended to increase PI (5.39-6.70, n=5, P=0.059). During these studies heart rate, mean ABP and p(a)CO(2) did not change significantly. The tendency for PI to increase in response to vasodilation was unexpected and the mechanism involved is unclear. It appears that femoral artery PI cannot be used to predict vasomotor tone in the digit of the anaesthetised sheep. 相似文献
718.
719.
The haematological response of regular, repeated blood harvesting was investigated in 40 Thoroughbred and non-Thoroughbred horses that donate 8 litres of blood every 3 weeks for the purposes of commercial blood production. When this volume of blood was removed on five occasions over 12 weeks, no adverse effect on packed cell volume (PCV), haemoglobin (HB), and red blood cell count (RCC) was observed. Although PCV, RCC and Hb values decreased during the first week after blood collection, followed by a gradual increase in values until the next harvest time, all values remained within published reference ranges. Derived red cell indices [mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), and mean corpuscular haemoglobin concentration (MCHC)] also remained within reference range. We conclude that the removal of approximately 8 litres of blood (approximately 16 ml kg(-1)or 20 per cent of blood volume for a 500 kg horse) from blood donor horses every 3 weeks allows time for adequate recovery of haematological variables and does not result in adverse haematological changes. 相似文献
720.
A closed household of 26 cats in which feline coronavirus (FCoV), feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV) were endemic was observed for 10 years. Each cat was seropositive for FCoV on at least one occasion and the infection was maintained by reinfection. After 10 years, three of six surviving cats were still seropositive. Only one cat, which was also infected with FIV, developed feline infectious peritonitis (FIP). Rising anti-FCoV antibody titres did not indicate that the cat would develop FIP. The FeLV infection was self-limiting because all seven of the initially viraemic cats died within five years and the remainder were immune. However, FeLV had the greatest impact on mortality. Nine cats were initially FIV-positive and six more cats became infected during the course of the study, without evidence of having been bitten. The FIV infection did not adversely affect the cats' life expectancy. 相似文献