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991.
Bovine tuberculosis (TB) in cattle is a major economic problem in Britain. In the past 25 years, the infection has been concentrated in the southwest region of England. We investigated the effects of agricultural and farm-management characteristics on the occurrence and scale of TB in cattle in the region (1988-1996) using logistic and linear regression. Factors relating to the existence of previous infection in cattle and the management of cattle and badgers are all linked to the incidence of the infection--but those related specifically to the management of cattle are of overriding importance in determining the scale of the problem. Although our analysis was conducted at a large spatial scale, the results suggest that improvements to the procedure for testing and managing TB in cattle, reductions in cattle stocking density, a greater human input in herd management and more-carefully targeted badger culling all might contribute to reducing the incidence and/or number of herd breakdowns.  相似文献   
992.
Hyperadrenocorticism in ferrets is usually associated with unaltered plasma concentrations of cortisol and adrenocorticotropic hormone (ACTH), although the urinary corticoid/creatinine ratio (UCCR) is commonly elevated. In this study the urinary glucocorticoid excretion was investigated in healthy ferrets and in ferrets with hyperadrenocorticism under different circumstances. In healthy ferrets and in one ferret with hyperadrenocorticism, approximately 10% of plasma cortisol and its metabolites was excreted in the urine. High-performance liquid chromatography (HPLC) revealed one third of the urinary corticoids to be unconjugated cortisol; the other peaks mainly represented cortisol conjugates and metabolites. In 21 healthy sexually intact ferrets, the UCCR started to increase by the end of March and declined to initial values halfway the breeding season (June). In healthy neutered ferrets there was no significant seasonal influence on the UCCR. In two neutered ferrets with hyperadrenocorticism the UCCR was increased, primarily during the breeding season. In 27 of 31 privately owned ferrets with hyperadrenocorticism, the UCCR was higher than the upper limit of the reference range (2.1 x 10(-6)). In 12 of 14 healthy neutered ferrets dexamethasone administration decreased the UCCR by more than 50%, whereas in only 1 of the 28 hyperadrenocorticoid ferrets did the UCCR decrease by more than 50%. We conclude that the UCCR in ferrets primarily reflects cortisol excretion. In healthy sexually intact ferrets and in ferrets with hyperadrenocorticism the UCCR increases during the breeding season. The increased UCCR in hyperadrenocorticoid ferrets is resistant to suppression by dexamethasone, indicating ACTH-independent cortisol production.  相似文献   
993.
This study examined the endoparasite load of a group of olive baboons (Papio cynocephalus anubis) that share their habitat with a population of mountain gorillas (Gorilla gorilla berengei) in Bwindi Impenetrable National Park, Uganda. During a 2-week period in June 2002, shared habitat was substantiated by noting the ranging patterns of both species and recording observations and trail remains with a global positioning system (GPS). Parasite load was determined by collecting fecal samples preserved in 10% formalin and analyzed by sedimentation techniques and immunofluorescent antibodies (IFA). Bwindi baboons were infected with Cryptosporidium, Giardia, Eimeria, Ascaris spp., Strongyloides spp., Trichuris spp., Hymenolepis spp., and Ternidens diminuta. Of these, the Bwindi mountain gorillas had previously been found to carry Cryptosporidium, Giardia, Strongyloides spp., and Trichuris spp., but not Eimeria, Ascaris, Hymenolepis, or T. diminuta. This study is the first to record Giardia in olive baboons and demonstrates that at least three parasite species in Bwindi baboons have yet to be found in Bwindi gorillas. Early monitoring is essential to the health and well being of both of these sympatric primate species, especially as they continue to interact more often and over a larger area.  相似文献   
994.
OBJECTIVE: To identify factors influencing satisfaction with procedures for small animal euthanasia and to compare the relative importance of those factors among clients, staff, and students at a veterinary teaching hospital. DESIGN: Survey. SAMPLE POPULATION: 18 nonclinical hospital staff members, 13 clinical staff members, 10 veterinary technicians, 19 veterinary students, and 91 clients. PROCEDURE: Participants were asked to complete a survey that was designed to assess satisfaction with various aspects of the euthanasia procedure. RESULTS: Overall response rate was 48% (151/313). Respondents most strongly agreed with the statements that clients should have the option to be present, that having a private place was important, and that employees should be trained to attend to the emotional needs of the client. When asked to place factors in order of importance, those that were ranked the highest included compassionate and caring attitudes of the hospital employees, the option for the client to be present during the euthanasia, and the client being informed and well prepared. CONCLUSIONS AND CLINICAL RELEVANCE: Overall, all groups (nonclinical staff, clinical staff, veterinary technicians, veterinary students, and clients) identified the same factors as being important in the euthanasia of a pet. Results may help facilitate healthy euthanasia experiences.  相似文献   
995.
OBJECTIVE: (1) To determine whether an extracapsular patellar ligament/fascia lata graft would provide stability in the cranial cruciate ligament (CrCL)-deficient stifle comparable with that of the intact stifle. (2) To determine if different tibial anchor points would enhance stability of the CrCLdeficient stifle when compared with the standard fabellar-tibial suture (FTS) placement. STUDY DESIGN: Experimental. ANIMALS: Twenty-eight canine cadaver hind limbs. METHODS: Stifles were mounted in a jig and tested between loads of -65 and 80 N. After testing the intact CrCL, 4 stabilization techniques were tested after CrCL transection: lateral graft technique (LGT) and 3 FTS with different tibial anchor points. RESULTS: There were no significant differences in displacement between the LGT and standard FTS, between the LGT and the intact CrCL, or between the FTS and the intact CrCL, in either the Securos or the Screw-washer experiments. Stiffness of the intact CrCL was significantly greater than that of any stabilization technique and the cut CrCL. The standard FTS showed the least displacement of all suture stabilization techniques. Differences in stiffness were not significant between the suture stabilization techniques. CONCLUSIONS: Securely anchored, the LGT results in a reduction in drawer motion similar to that of the intact CrCL and the standard FTS. Altering the tibial anchor point for the FTS does not improve stiffness or enhance stabilization of the CrCL-deficient stifle. CLINICAL RELEVANCE: The LGT could be used for the treatment of CrCL ruptures in the dog. A clinical study is recommended.  相似文献   
996.
The clinical, radiographic, magnetic resonance imaging (MRI), surgical and pathological findings related to an osteochondral lesion of the sacrum in a mastiff dog are described. The dog showed chronic signs of pain in its pelvic limbs. Radiography revealed a triangular mineralised opacity at the craniodorsal aspect of the sacrum consistent with sacral osteochondrosis. A T2-weighted spin-echo MRI revealed dorsal and lateral compression of the cauda equina. The osteochondral fragment was removed via a dorsal laminectomy, and the clinical signs resolved. Histological abnormalities in the fragment were consistent with a diagnosis of osteochondrosis.  相似文献   
997.
OBJECTIVE: To determine peak vertical force (PVF) and vertical impulse (VI) in cats that had or had not undergone bilateral forelimb onychectomy. ANIMALS: 26 healthy adult cats. PROCEDURE: Onychectomized cats (n = 13) had undergone surgery more than 6 months prior to the study. The PVF and VI were collected from all limbs of each cat with a 2-m pressure platform walkway. Cats were allowed to walk at a comfortable velocity, and acceleration was restricted to +/- 0.5 m/s2. Five valid trials were recorded for each cat with all trials collected in a single 1-hour session. All forces were normalized to and expressed as a percentage of the cat's body weight. RESULTS: Gait data were successfully collected in all cats. No significant difference was found for PVF or VI between cats that had or had not had onychectomy. Limb loads were greater in forelimbs than hind limbs for all trials. Mean PVF and VI in the forelimbs of cats in the nononychectomy group were 56.41% and 18.85%, respectively. Mean PVF and VI in the hind limbs of cats in the nononychectomy group were 50.22% and 14.56%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Gait analysis was successfully performed in cats with a pressure platform walkway. The absence of differences in PVF and VI between the 2 groups of cats suggests that bilateral forelimb onychectomy did not result in altered vertical forces measured more than 6 months after surgery in cats.  相似文献   
998.
The objective of this study was to determine whether the porcine mammary gland responds to increasing dietary CP concentration through changes in AA arteriovenous difference (a-v). Sixteen Landrace x Yorkshire lactating sows were provided ad libitum access to one of four isocaloric diets varying in CP concentration (7.8, 13.0, 18.2, and 23.5 %; as-fed basis). Litters were adjusted to 11 pigs within 48 h of birth. Sows were fitted with catheters in the carotid artery and main mammary vein on d 4. On d 10, 14, 18, and 22 of lactation, arterial and venous blood samples were obtained every 30 min over 6 h. Milk yield was estimated on d 11 and 21 using the D2O dilution technique. Final litter sizes on d 21 were 10.3, 11, 9.5, and 11 piglets for sows fed the 7.8, 13.0, 18.2, and 23.5% CP diets, respectively. Piglet ADG tended (P = 0.088) to increase with increasing dietary CP concentration and were 186, 221, 220, and 202 g for sows fed the 7.8, 13.0, 18.2, and 23.5% CP diet, respectively. Daily total milk yield on d 21 (kg milk/d) tended (P = 0.099) to increase, and average milk yield per nursed piglet (kg of milk-pig(-1)d(-1)) increased (P < 0.05) with increasing CP concentration and were, on a per-piglet basis, 0.95, 1.19, 1.14 and 1.13 kg of milk/d for the 7.8, 13.0, 18.2, and 23.5% CP diets, respectively. As dietary CP increased from 7.8 to 23.5%, isoleucine and leucine a-v increased linearly only (linear, P < 0.01); all other AA a-v increased, reached a maximum in sows fed 18.2% CP, and decreased thereafter in sows fed 23.5% CP (quadratic, from P = 0.10 to P < 0.05). Amino acid uptake by the entire udder and by each gland increased (linear, P < 0.05) with increasing dietary CP. Arteriovenous differences response to increasing day of lactation varied among AA, from no change for histidine, isoleucine, lysine, methionine, tryptophan, and valine, to a linear trend increase for arginine (P = 0.055), leucine (P = 0.064), phenylalanine (P = 0.101), and threonine (P = 0.057). In summary, for the majority of AA, a-v increased with increasing dietary CP concentration from 7.8 to 18.2%, but decreased when CP concentration exceeded 18.2%. In contrast, mammary AA uptake, piglet ADG and milk yield per pig increased linearly with increasing dietary CP, suggesting a coordinated regulation between AA delivery and transport to meet the demand for milk yield.  相似文献   
999.
1000.
A previous study described cutaneous lymphocytosis (CL) in 23 cats. The process resembles cutaneous pseudolymphoma in humans, a heterogeneous group of benign reactive proliferations of well‐differentiated lymphocytes in the skin of humans. Morphological and immunophenotypic characteristics do not offer reliable criteria to accurately predict the clinical outcome of feline CL or pseudolymphoma in humans. Presence of clonal cell populations is more consistent with a neoplastic process. In a previous study, feline CL lesions (20 cats) were evaluated for clonality using PCR, and only two cats had monoclonal T‐cell populations. Because false‐negative results may occur, the purpose of this study was to repeat the PCR using a revised primer set based on analysis of additional feline T‐cell receptor γ (TCRγ) sequences. DNA was isolated from 29 skin lesions and six internal organs of 20 cats. DNA integrity was assessed by glyceraldehyde‐3‐phosphate dehydrogenase PCR. Polymerase chain reaction clonality was performed using the revised primer set specific for feline TCRγ, and duplicate samples were evaluated. The PCR products were assessed by heteroduplex analysis. Clonal rearrangement of TCRγ was detected in 14 cats (24 of 35 tissues: 21 of 29 skin lesions and three of six internal organs); eight of these cats are still alive and six were euthanized. Monoclonal populations were seen in three of five cats that had involvement of internal organs. These findings indicate that feline CL is best considered as a slowly progressive process which may be reactive, but often evolves into a low‐grade indolent lymphoma. Funding: George H. Muller Fund for Research in Dermatology.  相似文献   
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