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21.
Twenty-four red deer hinds with their calves were released on to a newly established pure red clover sward and, 2 days later, red staining of the tail, perineum and hocks was observed. This was presumed to be of urinary origin. Observation of micturition showed that when urine was passed, it was a normal straw colour but it turned scarlet-red about 1 hour after exposure to air. Midstream urine remained the normal colour when held under a pure nitrogen atmosphere immediately after micturition, but it turned red when held in air in the dark, suggesting that the colour change was due to an oxidative rather than a photosensitive reaction. All deer grazing red clover were affected but this did not occur in deer grazing ryegrass/white clover swards. No adverse effects were observed in the deer grazing the red clover, and calf growth was significantly higher than on ryegrass/white clover, suggesting that the red urine had no effect on health or productivity.

Blood and urine analyses showed no signs of haemolysis, haematuria or haemoglobinuria. Preliminary chemical analyses suggest that the compounds involved are not those found in the urine of sheep grazing oestrogenic clover. The nature of the compounds have yet to be determined.  相似文献   
22.
Objective – To compare the placement feasibility and amount of bone trauma induced by 3 intraosseous (IO) access techniques in cats: an automatic impact penetration device (A), an automatic rotary insertion device (B), and a manual IO needle (C). Design – Prospective ex vivo study. Setting – University. Animals – Eighteen adult mixed breed feline cadavers. Interventions – Cadavers provided 72 total IO insertion locations divided equally between the right and left humerus and tibia. The 3 IO techniques were randomly allocated to these locations. Time to successful insertion, ease of insertion, and success rate were recorded. Each insertion site was analyzed for the number of bone fragments and defect diameter by computed tomography. Measurements and Main Results – Device B had lower time of insertion (P=0.01) compared with devices A and C. Device B had better ease of insertion scores (P<0.01) compared with devices A and C. No differences were detected between insertion sites (tibia versus humerus). No differences in the number of bone fragments, defect diameter, or success rate were detected among devices (P=0.06, 0.31, and 0.14, respectively). Conclusions – All 3 IO access methods evaluated yield acceptable results. Device B is significantly faster and easier to place in cat cadavers when compared with other methods.  相似文献   
23.
OBJECTIVE: To determine the effect of meperidine administered prior to anesthesia on the incidence of vomiting before, and gastroesophageal reflux (GER) and regurgitation during, the subsequent period of anesthesia in dogs. STUDY DESIGN: Randomized, controlled trial. ANIMALS: A total of 60 healthy dogs, 4.3 +/- 2.3 years old, and weighing 35.5 +/- 13.1 kg. METHODS: Dogs were admitted to the study if they were healthy, had no history of vomiting, and were scheduled to undergo elective orthopedic surgery. The anesthetic protocol used was standardized to include thiopental and isoflurane in oxygen. Dogs were randomly selected to receive one of the following pre-medications: morphine (0.66 mg kg(-1) IM) with acepromazine (0.044 mg kg(-1) IM), meperidine (8.8 mg kg(-1) IM) with acepromazine (0.044 mg kg(-1) IM) or meperidine alone (8.8 mg kg(-1) IM). A sensor-tipped catheter was placed to measure esophageal pH during anesthesia. Gastro-esophageal reflux was judged to have occurred if there was a decrease in esophageal pH below four or an increase above 7.5. RESULTS: No dogs vomited after the administration of meperidine, but 50% of dogs vomited after the administration of morphine. When compared with morphine, treatment with meperidine alone or combined with acepromazine before anesthesia was associated with a 55% and 27% reduction in absolute risk of developing GER, respectively. Dogs receiving meperidine alone were significantly less sedate than other dogs in the study, and required more thiopental to induce anesthesia. Arterial blood pressure and heart rate were not significantly different between groups at the start of the measurement period. Cutaneous erythema and swelling were evident in four dogs receiving meperidine. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of meperidine to healthy dogs prior to anesthesia was not associated with vomiting and tended to reduce the occurrence of GER, but produced less sedation when compared with morphine. Meperidine is not a useful addition to the anesthetic protocol if prevention of GER is desired.  相似文献   
24.
25.
The history, clinical signs, results of diagnostic imaging, treatment methods and outcome of 16 adult horses with a metallic foreign body in the tongue are reviewed. All the horses had a swollen tongue, they salivated excessively and were partially to completely anorexic. Less common clinical signs were fever, an enlarged and painful intermandibular space, dysphagia, unilateral tongue paralysis and halitosis. Most of the horses had shown clinical signs for less than 24 hours. The foreign bodies were diagnosed by oral examination, radiography and ultrasonography; they were removed from the tongue of four of the horses during the initial oral examination, and were removed surgically from nine others; the other three horses were treated medically without attempts being made to extract the foreign bodies. Twelve of the bodies were small pieces of wire and one was a hypodermic needle. All the horses received a combination of antimicrobial and non-steroidal anti-inflammatory drugs and they all made an uneventful recovery. Feeding hay and the use of cable-framed tractor tyres as feeders were commonly associated with the cases.  相似文献   
26.
Progressive multisystemic disease caused by Blastomyces dermatitidis was diagnosed in a 17-year-old Quarter horse broodmare. The mare had been treated unsuccessfully with antibiotics for mastitis 3 months postpartum. The disease progressed to exudative cutaneous lesions affecting the ventrum, pectoral region, and limbs accompanied by weight loss across several months. Yeast bodies were observed in swabs of the cutaneous exudate, suggesting a clinical diagnosis of blastomycosis. Following referral, pleural effusion, cavitated lung lesions, and hyperproteinemia were identified, and the mare was euthanized because of poor prognosis. Necropsy revealed extensive pyogranulomas in the mammary gland, skin, subcutaneous tissues, and lungs, accompanied by thrombi in major blood vessels of the lungs and hind limbs. Histologically, pyogranulomatous inflammation was evident in many tissues, and fungal organisms were seen in sections of mammary gland, skin, subcutis, pericardium, and lung. Blastomyces dermatitidis was cultured from mammary tissue, lungs, lymph node, and an inguinal abscess. Although blastomycosis is endemic in the area of origin of the mare in northwestern Wisconsin, the disease is extremely rare in horses and hence easily misdiagnosed. Unique features of this case included the extent of mammary gland involvement and the presence of thrombi in multiple sites.  相似文献   
27.
The intercondylar fossa is believed to play an important role in the pathology of cranial cruciate ligament rupture and therefore has received considerable attention in the last decade. Accurate radiographic imaging of the intercondylar fossa requires that the central x-ray beam pass through the center of the intercondylar "tunnel". The anatomy of the canine intercondylar fossa is similar to humans, however, the orientations of the intercondylar fossa's differ. Consequently, the positioning techniques described for humans are not appropriate for the dog. To pass through the center of the dog, intercondylar fossa, the central x-ray beam should be 12° (S.D. 1.7°) caudal from the femoral diaphysis in the sagittal plane and obliqued caudolateral to craniomedial 7° (S.D. 0.60°) (caudo78°proximo7° lateralcraniodistomedial oblique). Cross table positioning was used with the hip flexed and the radiograph cassette placed on the cranial surface of the stifle. However, superimposition of the tuber ischii and soft tissues caudal to the femur made 15° to 20° the best angle obtainable. There was not a significant difference (p = 0.17) in the notch width index between a 12° versus 20° angle of the central x-ray beam caudal to the femoral diaphysis, both with 7° of external rotation of the stifle. The notch width index of 0.252 obtained from radiographic measurements was not significantly different from measurements obtained grossly of 0.254 (n = 26; p = 0.69). Failure to oblique the central x-ray beam caused a significant (p = 0.0008) decrease in the apparent fossa width radiographically.  相似文献   
28.
AIMS: This study was initiated to investigate aspects of the epidemiology, pathogenesis and transmission of tuberculosis in wild red deer, with the aim of determining whether this species may be considered a reservoir host of Mycobacterium bovis in New Zealand. METHOD: One hundred and six wild red deer (Cervus elaphus) carcasses from the Castlepoint and Hauhungaroa Range areas, which are endemic for bovine tuberculosis, were examined for the presence of M. bovis infection. Samples were also examined from 46 skin test-positive farmed deer killed at two deer slaughter premises. Where possible, a standard set of tissues and excretion site samples was collected for mycobacteriological examination. RESULTS: Fifty-eight infected deer were identified, and of these 28% showed no gross lesions. The prevalence of tuberculosis confirmed by culture in the wild deer was 32%. Only one of 18 deer younger than 1 year was infected. Mature deer (>2 years) were 12 times more likely to be infected than those under 1 year of age. Infected older deer were less likely to show typical gross lesions than younger animals. Mycobacterium bovis was isolated from the oropharyngeal tonsil of 34 of 56 (61%) of the infected deer, and this was the most commonly infected site. Gross lesions were found in 18 of the 34 infected tonsils and only one of these showed a purulent tonsillitis. Mycobacterium bovis was recovered from four of 53 nasopharyngeal tonsils, four of 53 oropharyngeal swabs, one of 53 tracheal and nasal swabs, and one of 46 faecal samples, but not from any urine specimens. CONCLUSION: These findings suggest that significant bacillary excretion from infected deer was uncommon, and is more likely to occur in severely affected animals. This study has confirmed the importance of mucosa-associated lymphoid tissues (MALT), particularly the oropharyngeal tonsil, in the pathogenesis of tuberculosis in deer. The findings justify investigation of the hypotheses that the prevalence of tuberculosis in wild deer in New Zealand is high due to transmission of infection from possums, and that in the absence of an infected possum population, the prevalence of tuberculosis in deer is likely to be low, and spatially patchy. CLINICAL RELEVANCE: The results suggest that about one quarter of infected deer show no detectable gross lesions. This implies that many infected carcasses may enter the food chain unrecognised and that the estimated sensitivity and specificity of diagnostic tests may be erroneous if there is a difference in test performance between those conducted on deer with or without gross lesions. Diagnostic sensitivity following slaughter may be improved by routine culture of oropharyngeal tonsils and careful examination of lungs for adhesions and small subpleural tubercles.  相似文献   
29.
The six countries comprising the Horn of Africa are Djibouti, Eritrea, Ethiopia, Kenya, Sudan and Somalia. Together, they cover an area of just under 5 million square kilometres and support a human population of 17.7 million at an average density of 38.15 people per square kilometre (although in the purely pastoral areas population density is probably of the order of 15–16 people per square kilometre). The Horn is a major repository of domestic animal biodiversity and genetic resources and is home to 15 million one-humped camels, 110 million cattle, 94 million goats and 102 million sheep. A list of 72 sheep “breeds” of which 23 can be considered fat-tailed or fat-rumped has been compiled for the area, although many of these are merely subtypes of a larger grouping and several are not native to the Horn. This paper provides information, where such is available, on the distribution, numbers and production parameters of the fat-tailed and fat-rumped sheep that occupy the Horn.  相似文献   
30.
Bovine tuberculosis (TB) is a serious zoonotic disease, which despite a largely successful test and slaughter programme has persisted in cattle herds in parts of the UK. The badger (Meles meles) is widely considered to represent a significant wildlife reservoir for the transmission of Mycobacterium bovis to cattle, and has been the subject of a variety of culling strategies since the mid 1970s. Nevertheless, the incidence of herd breakdowns has continued to rise, and the efficacy of culling is currently the subject of a large-scale field trial. One potential alternative tool for the management of disease in wildlife populations is vaccination. However, the successful development of an effective vaccine and a strategy for its delivery will require careful consideration of the practical constraints imposed by ecological factors. In the current paper, we discuss relevant ecological and epidemiological characteristics of badger populations and practical aspects of vaccine delivery in the field.  相似文献   
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