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71.
Objective To compare haematological values and lymphocyte phenotypes in the peripheral blood of fleece rot-resistant and -susceptible sheep.
Procedure Experiments were conducted on 2- and 3-year-old Merino rams, flock 1 (17 rams) and flock 2 (32 rams), respectively. Within each flock, individual rams were classified as fleece rot-resistant or -susceptible, based on established criteria. Total and differential white cell counts, and indirect fluorescent antibody tests specific for B cells and T cells were performed on all sheep. The concentration of various subsets of circulating lymphocytes was then determined in each sheep.
Results There were no significant differences between fleece rot-resistant and -susceptible sheep from either flock in the mean total or differential white cell counts. However, fleece rot-resistant rams in flock 1 did have a significantly higher concentration of circulating SBU-T1+ cells than fleece rot-susceptible rams from the same flock. No such difference was noted in the rams from flock 2. While all rams in flock 1 were free of clinical fleece rot, 24 rams in flock 2 (comprising all 17 fleece rot-susceptible and 7 of 15 fleece rot-resistant animals) had clinical signs of the disease. Fleece rot-free rams in this flock (irrespective of their classification as fleece rot-resistant or -susceptible) had significantly higher concentrations of circulating SBU-T1+ cells compared with fleece rot-affected animals. They also had significantly higher concentrations of circulating B cells, and total lymphocytes.
Conclusions An examination of peripheral blood lymphocyte subsets in fleece rot-resistant and -susceptible sheep revealed a possible association between resistance to fleece rot and the concentration of circulating SBU-T1+ cells.  相似文献   
72.
During the early history of the solar system, it is likely that the outer planets changed their distance from the sun, and hence, their influence on the asteroid belt evolved with time. The gravitational influence of Jupiter and Saturn on the orbital evolution of asteroids in the outer asteroid belt was calculated. The results show that the sweeping of mean motion resonances associated with planetary migration efficiently destabilizes orbits in the outer asteroid belt on a time scale of 10 million years. This mechanism provides an explanation for the observed depletion of asteroids in that region.  相似文献   
73.
This review summarises research of management practices that potentially impact on the welfare of farmed deer. The processes of capture and initial domestication of feral deer caused many welfare problems but are now essentially complete in New Zealand. The health and production status of farmed deer, and readily visible indicators of their welfare are generally good, although preventive medicines and optimum management practices have not been universally adopted. Research into social behaviour, effects of yarding, weaning, mating, calving, shelter, shade and nutrition has identified ways of improving the welfare of farmed deer and has provided recommendations for deer industry quality assurance programmes. Research has identified transport design and practices that minimise the impact of transport on deer welfare and reduce carcass wastage caused by bruising during transport. Time in lairage prior to slaughter should be minimised and electrical stunning is a humane method of slaughter. Ongoing research is needed on management practices and farm environments to further improve the welfare of farmed deer, consistent with the goals of the New Zealand deer industry and its proactive approach to date.  相似文献   
74.
AIM: To identify whether cutting neck tissues or cutting major blood vessels initiates the mechanisms responsible for electroencephalographic (EEG) responses to slaughter by ventral-neck incision without prior stunning in halothane-anaesthetised calves.

METHODS: Calves were assigned to two groups, viz transection of neck tissues with intact blood circulation through the brain (n=10), or transection of the major blood vessels of the neck but not most other neck tissues (n=7). They were minimally anaesthetised with halothane, using an established anaesthesia protocol. The animals in the neck-tissue transection group had their carotid arteries and jugular veins exposed and cannulated proximal and distal to the proposed site of subsequent ventral-neck incision; this diverted blood fl ow through these vessels so that cerebral perfusion and drainage were preserved. In animals in the blood-vessel transection group, the carotid arteries and jugular veins were exposed bilaterally by surgical dissection. They were then transected without further damage to the remaining structures of the neck. Changes in the median frequency (F50), 95% spectral edge frequency (F95), total power of the EEG (Ptot), and arterial blood pressure were compared within each group before and after neck-tissue or blood-vessel transection, and between groups following treatments.

RESULTS: Neck-tissue transection resulted in little overall change in the F50, an increase in the F95, and an initial increase in Ptot followed by a transient decrease and eventual return to pre-treatment values. There was between-animal variation in these EEG parameters. Transection of the major blood vessels of the neck resulted in a decrease in F50 in most animals; changes in F95 were highly variable, and there was a decrease in Ptot.

CONCLUSIONS: The EEG responses seen following necktissue and blood-vessel transection were qualitatively distinct, and suggested that cutting neck tissues caused greater noxious sensory input than transection of only the major blood vessels of the neck. These observations support the conclusion that the EEG responses seen after ventral-neck incision in intact animals are primarily due to noxious stimulation as a result of incision of ventral-neck tissues and not mainly as a result of loss of blood flow through the brain.  相似文献   
75.
This case report describes neurological signs associated with a pyogranulomatous lesion within the sacral vertebral canal of a horse. The clinical findings included urinary overflow incontinence and reduced anal, perianal and tail tone. The horse failed to respond to medical management and a guarded prognosis for return to athletic performance initiated the decision for euthanasia.  相似文献   
76.
A set of seven principles (the 'Sydney Principles') was developed by an International Obesity Taskforce (IOTF) Working Group to guide action on changing food and beverage marketing practices that target children. The aim of the present communication is to present the Sydney Principles and report on feedback received from a global consultation (November 2006 to April 2007) on the Principles. The Principles state that actions to reduce marketing to children should: (i) support the rights of children; (ii) afford substantial protection to children; (iii) be statutory in nature; (iv) take a wide definition of commercial promotions; (v) guarantee commercial-free childhood settings; (vi) include cross-border media; and (vii) be evaluated, monitored and enforced. The draft principles were widely disseminated and 220 responses were received from professional and scientific associations, consumer bodies, industry bodies, health professionals and others. There was virtually universal agreement on the need to have a set of principles to guide action in this contentious area of marketing to children. Apart from industry opposition to the third principle calling for a statutory approach and several comments about the implementation challenges, there was strong support for each of the Sydney Principles. Feedback on two specific issues of contention related to the age range to which restrictions should apply (most nominating age 16 or 18 years) and the types of products to be included (31% nominating all products, 24% all food and beverages, and 45% energy-dense, nutrient-poor foods and beverages). The Sydney Principles, which took a children's rights-based approach, should be used to benchmark action to reduce marketing to children. The age definition for a child and the types of products which should have marketing restrictions may better suit a risk-based approach at this stage. The Sydney Principles should guide the formation of an International Code on Food and Beverage Marketing to Children.  相似文献   
77.
SUMMARY: Free radical oxidation products, namely conjugated dienes, ultraviolet fluorescence (excitation 325 nm, emission 395 nm) and visible fluorescence (excitation 360 nm, emission 460 nm) were measured in equine synovial fluid exposed to free radicals In vitro and in the plasma and synovial fluids of horses with synovial effusions. The synovial effusions were induced by intra-articularly administered carrageenin (0.3 ml, 1%), which rarely resulted in clinical lameness. The free radicals were generated In vitro by mixtures of iron and ethylene diamine tetra acetate (Fe/EDTA) or mixtures of hypoxanthine and xanthine oxidase (HX/XO). The conjugated diene concentrations and intensity of ultraviolet fluorescence were negligible in plasma and synovial fluid specimens. No increase resulted from incubation of synovial fluids with either a free radical generating system or as a result of the induced inflammation. The intensity of visible fluorescence did not increase in specimens incubated with Fe/EDTA. However, the intensity of visible fluorescence increased in specimens incubated with HX/XO, in synovial effusions induced by carrageenin, in plasma and in synovial fluids aspirated from saline injected controls. The results indicate that the intensity of visible fluorescence of equine synovial fluid increases after exposure to free radicals and during synovitis in the horse, suggesting a possible role for free radicals in the pathogenesis of equine inflammatory joint diseas  相似文献   
78.
The availability of cow ovaries from the slaughterhouse has been very limited in Taiwan. To maximize the use of cow ovaries for research purposes, whole ovary dissection was performed and the developmental competence of the oocytes derived from different sizes of follicles was assessed by the rates of in vitro maturation (IVM) and parthenogenetic activation of the oocytes in Experiment 1 (Exp 1). Cumulus-oocyte complexes (COCs) derived from small (1-2 mm) and large (3-8 mm) follicles were subjected to standard IVM culture for 24 h. Mature oocytes were selected and then parthenogenetically activated using A23187 (5 microm, 5 min) or thimerosal (200 microm, 10 min) alone or combined with 6-dimethylaminopurine (2.5 mm and 3.5 h, respectively). Activation rates of the oocytes, neither from the large nor small follicles, were affected by different activation treatments (single or combined stimuli). Whereas maturation rates for the oocytes from large follicles were superior to those from small follicles in both the single (59% vs 45%) and combined treatments (76% vs 40%; p < 0.05). To understand how prolonged heat shock (HS) influences cytoskeletal configurations of mature bovine oocytes, in Experiment 2 (Exp 2), matured oocytes derived from large follicles were randomly allocated to different durations of HS treatments at 41.5 degrees C for 0 (C0h, control, n = 12), 1 (HS1h, n = 28), 2 (HS2h, n = 31), and 4 h (HS4h, n = 30). An additional control group was cultured for 4 h without HS (38.5 degrees C, 4 h, n = 35). Alterations in nuclear structures, microtubules (MTs), and microfilaments (MFs) of the oocytes were examined. Abnormalities in the chromosomes, spindle MTs and the percentages of oocytes with cytoplasmic MTs increased with time of HS treatment. The intensity of the MF distribution in the HS oocytes was also altered. Significant changes in the cytoskeleton after HS may be associated with the reduced development under hyperthermia and, perhaps, with the low pregnancy rates of the animals during hot seasons.  相似文献   
79.
This retrospective study examined the case records of Old World screw-worm fly myiasis in dogs in Hong Kong's New Territories. Myiasis due to OWSWF was identified and treated in 59 dogs at our clinic over a period of 1 year. Signalment, causes of initial wound, and treatments implemented, are reported. All cases recovered from myiasis with a combination of larvae removal and wound debridement, antibiotics, and topical and systemic insecticides. Whilst this parasite is currently exotic to Australia, much of the country is environmentally suitable (tropical and subtropical) for establishment of OWSWF.  相似文献   
80.
The Glutaraldehyde test (GT), a rapid and inexpensive test, has been utilized empirically for many years in bovine practice for diagnosing inflammatory diseases. GT is used primarily to demonstrate increased serum concentrations of fibrinogen and globulin. Glutaraldehyde binds with free amino groups in fibrinogen and immunoglobulin to create a clot in a first degree chemical reaction. The clotting time of the GT estimates the content of proteins produced in response to inflammation. The applicability of GT for diagnosing inflammation in the horse has never been investigated. The objective of this study was to determine the ability of GT to distinguish between acute and chronic inflammatory disease in horses. Thirty-seven horses with suspected inflammatory diseases were evaluated using the GT, history, complete clinical examination and routine blood analysis. GT-times, laboratory results and clinical outcome were compared statistically. Horses that were determined to be acutely affected (based on history, clinical examination and routine blood analysis) tended to have a negative GT (75%). Results of the GT did not correlate with blood fibrinogen concentration. Positive GT also predicted a fatal outcome in 69% of the clinical cases. The results of this trial indicate that GT can be a useful screening test to distinguish between acute and chronic inflammatory disease in horses.  相似文献   
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