Use of a nerve locator to facilitate administration of mandibular nerve blocks in crocodilians.     

James F X Wellehan  Cornelia I Gunkel  David Kledzik  Sheilah A Robertson  Darryl J Heard 《Journal of zoo and wildlife medicine》2006,37(3):405-408

As part of a clinical workup of dental problems in a large crocodilian collection, mandibular nerve blocks were performed in the animals. A nerve locator was used to facilitate placement of the nerve blocks in American alligators (Alligator mississippiensis), Yacare caiman (Caiman yacare), and a dwarf crocodile (Osteolaemus tetraspis). Provision of analgesia is a frequently underused aspect of patient care in reptiles. Use of a nerve stimulator provides an objective measurement of nerve conduction blockade and may be useful in exotic species in which anatomic landmarks for nerve block placement are not well established.  相似文献   

Vaccination of Egyptian fruit bats (Rousettus aegyptiacus) with monovalent inactivated rabies vaccine.     

Christina Peters  Ramiro Isaza  Darryl J Heard  Rolan D Davis  Susan M Moore  Deborah J Briggs 《Journal of zoo and wildlife medicine》2004,35(1):55-59

Twenty-six captive, adult Egyptian fruit bats (Rousettus aegyptiacus) were tested for the presence of rabies virus neutralizing antibodies (RVNA) using a rapid fluorescent focus inhibition test before and after vaccination. The bats were randomly assigned into three treatment groups: group A (n = 10) bats each received one 0.1-ml dose of monovalent inactivated rabies vaccine, group B (n = 10) bats each received two 0.1-ml doses of vaccine given 30 days apart, and group C (n = 6) bats remained unvaccinated. Plasma was collected from all bats before vaccination and on days 14, 30, 60, and 360. All bats were seronegative before vaccination, and all unvaccinated animals remained negative throughout the study. Rabies virus neutralization titers remained above 0.5 IU/ml from day 30 through day 360 for both vaccinated groups. Group B had significantly higher titers on day 60. This study demonstrated a measurable humoral immune response after vaccination with an inactivated rabies vaccine, with two doses producing a higher level of RVNA. This study confirms the feasibility of a rabies vaccination program for Egyptian fruit bats.  相似文献   

Subtle changes in rhizosphere microbial community structure in response to increased boron and sodium chloride concentrations     

Darryl R. Nelson  Pauline M. Mele 《Soil biology & biochemistry》2007,39(1):340-351

Two of the major constraints to grain production in large areas of South-East Australia and cropping soils worldwide are high levels of subsoil boron (B) and excessive salinity (NaCl). Although the effect of these constraints is often studied in plants, the effect on microbially mediated plant-beneficial processes is unclear. To that end, we investigated the impact of B and NaCl on soil microbial community structure (MCS) in the wheat rhizosphere using BIOLOG ecoplates and terminal restriction fragment length polymorphism (T-RFLP). In addition, the effects of B and NaCl on the nitrogen (N) cycle processes of N fixation and ammonia oxidation were assessed by the construction of clone libraries of diazotrophic (nifH) and ammonia oxidising (amoA) rhizobacteria. Analysis of BIOLOG plates using non-metric multidimensional scaling (MDS) revealed addition of both B and NaCl significantly changed MCS, the latter of which was also significant through the analysis of T-RFLP data. Utilisation of several chemical groups of BIOLOG substrates significantly changed in NaCl-amended soil; both B and NaCl affected utilisation of several individual substrates indicative of plant stress including serine and malic acid. A significant decrease in diversity and species richness was observed in high B rhizosphere soil. The community structure of ammonia-oxidising bacteria (AOB), all of which clustered with Nitrosospira-like sequences, did not significantly change in response to addition of B or NaCl, but addition of the latter resulted in a significant increase of diazotroph clones within the α-proteobacteria similar to Azospirillum sp. It appeared that the addition of B and NaCl to soil changed rhizosphere MCS indirectly through increased soil moisture and subtle changes in root exudate patterns, the addition of the latter producing a more distinct change through increased osmotic pressure, leading to a greater increase in rhizodeposition of nutrients, especially carbohydrates. The implications for the current study are that B and NaCl are more likely to affect rhizosphere MCS indirectly through root exudate quantity and/or quality than directly through microbial toxicity, and that plant health is a major determinant in rhizosphere MCS and normal N cycling.  相似文献   

Lifelong diet restriction and radiographic evidence of osteoarthritis of the hip joint in dogs     

Smith GK  Paster ER  Powers MY  Lawler DF  Biery DN  Shofer FS  McKelvie PJ  Kealy RD 《Journal of the American Veterinary Medical Association》2006,229(5):690-693

OBJECTIVE: To evaluate the effects of diet restriction on development of radiographic evidence of hip joint osteoarthritis in dogs. DESIGN: Longitudinal cohort study. ANIMALS: 48 Labrador Retrievers from 7 litters. PROCEDURES: Forty-eight 6-week-old puppies from 7 litters were paired with littermates by sex and weight, and each pairmate was randomly assigned to 1 of 2 groups of 24 dogs each. Starting at 8 weeks of age, 1 group was fed ad libitum (control fed) and the other was fed 25% less (restricted fed) of the same diet for life on a pairwise basis. The dogs' hip joints were radiographed in the standard ventrodorsal hip-extended view at multiple intervals prior to 1 year of age and at annual intervals thereafter on the basis of birth anniversary. A board-certified radiologist unaware of group assignment scored the radiographs for evidence of osteoarthritis. RESULTS: Prevalence of radiographic evidence of hip joint osteoarthritis in all dogs increased linearly throughout the study, from an overall prevalence of 15% at 2 years to 67% by 14 years. Restricted-fed dogs had lower prevalence and later onset of hip joint osteoarthritis. Median age at first identification of radiographic evidence of hip joint osteoarthritis was significantly lower in the control-fed group (6 years), compared with the restricted-fed group (12 years). CONCLUSIONS AND CLINICAL RELEVANCE: Restricted feeding delayed or prevented development of radiographic signs of hip joint osteoarthritis in this cohort of Labrador Retrievers. Lifetime maintenance of 25% diet restriction delayed onset and reduced severity of hip joint osteoarthritis, thus favorably affecting both duration and quality of life. In addition, the data indicated that development of hip joint osteoarthritis was not bimodal in these dogs but occurred as a continuum throughout life.  相似文献   

Future directions in reptile medical education     

Jacobson E  Heard D  Isaza R 《Journal of veterinary medical education》2006,33(3):373-381

Reptile medicine has emerged as a specialty area within the broader field of zoological medicine. It encompasses the medical needs of approximately 7,500 vertebrate species. This vertebrate class is highly diversified, having biological and medical peculiarities that differ both between and within major groups. Historically, veterinarians who have become recognized specialists with reptiles have had limited formal training in their medical management. The pet reptile trade is a multi-million-dollar business, and the popularity of reptiles as pets has resulted in a need for more veterinarians with training in their medical management. While few private practices have high volumes of reptile cases, many small-animal practices will have the opportunity to see a significant number of reptiles on an annual basis. Most practitioners with reptile medical expertise have merged their experiences as reptile pet owners with the principles of veterinary medicine taught in veterinary college. Several North American veterinary colleges have reptile medicine courses, and most have didactic and clinical courses in exotic and zoo animal medicine that include lectures and practical experience. Most accredited zoological medicine residency training programs include training in reptile medicine. The case load and interest in reptile medicine will probably never be sufficient to lead the average veterinary college to develop much more than what is currently offered. Consequently, those few colleges having more extensive course offerings, both didactic and clinical, will serve as educational centers for this discipline. Future Web-based teaching programs in reptile medicine will allow students nationally and internationally to have access to instructional material that can be continually updated.  相似文献   

Essential oil of Valeriana officinalis L. cultivars and their antimicrobial activity as influenced by harvesting time under commercial organic cultivation     

Letchamo W  Ward W  Heard B  Heard D 《Journal of agricultural and food chemistry》2004,52(12):3915-3919

The essential oil content and the composition of subterranean parts of two valerian (Valeriana officinalis, L.) cultivars Select and Anthose, from certified commercial organic fields, were determined by hydrodistillation, followed by gas chromatography (GC) and GC/mass spectrometry analysis. Eight and fourteen month old cv. Select had 0.67 and 0.87% essential oil, while similar aged cv. Anthose contained 0.97 and 1.1% essential oil. Forty-three and fifty-three components from cv. Select and cv. Anthose oils were detected, respectively. The oil composition significantly varied due to the cultivar type, plant age, and/or harvesting time. The major components for cv. Select were valerenal, bornyl acetate, 15-acetoxy valeranone, valerenic acid, and camphene, while cv. Anthose had valerenal, (-)-bornyl acetate, alpha-humulene, camphene, 15-acetoxy valeranone, and valerenic acid. With further aging of the plants, the valerenal, valerenic acid, and alpha-humulene contents increased. The oil of cv. Select had a strong antimicrobial effect against Aspergillus niger, Escherichia coli, Staphylococcus aureus, and Saccharomyces cerevisiae, while cv. Anthose showed low or no activity against all test microbes, including Pseudomonas aeruginosa, suggesting that the inhibitory activity of valerian oil depends on the cultivar and its developmental stage. The oil profile of our cultivars did not match the literature proposed chemotype profiles.  相似文献   

Restoration versus recolonisation: The origin of Atlantic salmon (Salmo salar L.) currently in the River Thames     

Andrew M. Griffiths  Jonathan S. Ellis  Darryl Clifton-Dey  Gonzalo Machado-Schiaffino  Dylan Bright  Eva Garcia-Vazquez  Jamie R. Stevens 《Biological conservation》2011,144(11):2733-2738

Since the 1970s, when major improvements to the water quality were made, the River Thames has been subject to a high-profile project aimed at restoring Atlantic salmon to the catchment. Whilst initially successful, with hundreds of salmon returning each year in the late 1980s, the number of adults returning to the river has declined steeply again in recent years, reaching a low in 2005 when no salmon were recorded. Using a baseline of genetic information gathered from 3830 salmon from throughout their southern European range, and incorporating samples from the hatchery fish used to stock the Thames, all 10 tagged hatchery fish captured in 2003 and all 16 returning untagged adult salmon captured between 2005 and 2008 were assigned to their most likely river of origin. The results suggest that untagged salmon currently ascending the river originate not from exogenous fish stocked into the Thames, but predominantly from other rivers in southern England. This highlights the potential for natural processes of recolonisation to operate in rivers where salmon have become locally extirpated. These findings also underscore several important considerations when undertaking species restoration projects: (i) previous causes of declines must be sufficiently ameliorated to allow new/translocated individuals to thrive, (ii) introduced individuals should originate from a stock that is closely related to the extirpated population, according to the principles of contemporary conservation biology, and (iii) dispersal and gene-flow from neighbouring populations may play a significant role in establishing new populations.  相似文献   

Sorption of Polymeric Quaternary Ammonium Compounds to Humic Acid     

Janet Cumming  Darryl William Hawker  Heather Chapman  Kerry Nugent 《Water, air, and soil pollution》2011,214(1-4):5-11

Polymeric quaternary ammonium salts or polyquaterniums are used not only in the water and wastewater industry but also in cosmetics. The former have been extensively studied with sorption to wastewater treatment plant (WWTP) biosolids an important factor in their fate, mitigating release to the environment. Compounds of cosmetic origin have not received the same scrutiny as those used in other applications despite differences in their structure, characteristics and properties such as toxicity. In this work, the sorption of selected polyquaterniums found in cosmetics to treated humic acid, employed as a surrogate for WWTP biosolids, is investigated. For comparison, the sorption of poly(diallyldimethylammonium chloride) (poly(DADMAC)), a polyquaternium commonly used as a flocculant, and cetyl pyridinium chloride, a monomeric quaternary ammonium compound, are also determined. The humic acid/water partition coefficients (K _D) of cetyl pyridinium chloride (52,000?L?kg^?1) and poly(DADMAC) (2,200?L?kg^?1) were greater than those of the polyquaterniums found in cosmetics (200 to 1,200?L?kg^?1). Assumptions of partitioning mainly to biosolids and substantial removal relative to the influent concentration of WWTPs may therefore not be valid.  相似文献   

Pes varus correction in Dachshunds using a hybrid external fixator     

Radasch RM  Lewis DF  McDonald DE  Calfee EF  Barstad RD 《Veterinary surgery : VS》2008,37(1):71-81

Objective— To describe surgical correction of pes varus deformity in Dachshunds by acute medial opening wedge osteotomy of the distal aspect of the tibia stabilized with a hybrid external skeletal fixator (HESF), and report clinical and radiographic outcomes.
Study Design— Multicenter, retrospective clinical study.
Animals— Immature Dachshunds (n=13) with pes varus deformity.
Methods— Limb function and lameness scores were assigned before and after surgery, and correction was determined visually at surgery. Tibiotarsal joint orientation (TTJO) and medial and lateral tibial cortex lengths, measured on radiographs of deformed and normal (when available) limbs, were compared before correction and after fixator removal.
Results— Pes varus deformities (n=14) were corrected; 93% had good to excellent clinical outcome. None of the dogs had a normal preoperative gait. Mean TTJO of abnormal and normal tibiae before surgery were 29° varus (median, 28°), and 12° valgus (median, 12°). Angular correction ranged from 20° to 51° (mean, 36±8°; median, 36°). M e an TTJO after fixator removal was 7° valgus (median, 7°). Two dogs had minor transient postoperative complications whereas 3 had major complications; only 1 of which was resolved.
Conclusions— Pes varus deformity in Dachshunds can be corrected by acute medial opening wedge osteotomy of the distal aspect of the tibia stabilized by HESF. Technique modifications are needed to improve correction precision.
Clinical Relevance— Visual inspection of limb alignment during surgery resulted in good to excellent clinical outcomes; however, 91% of tibiae were under- or overcorrected (mean, 6°; median, 5°). Limb alignment should be based on evaluation of immediate postoperative TTJO measurements, not solely on intraoperative visual assessment.  相似文献   

Reptile anesthesia.     

D J Heard 《Veterinary Clinics of North America: Exotic Animal Practice》2001,4(1):83-117, vii

Successful reptile anesthesia requires patience, planning, and understanding of normal anatomy and physiology in health and disease. Reptiles make good anesthetic patients because of their physiologic resilience. New drugs that are not only safe and efficacious, but also result in relatively short recovery times, have greatly enhanced the design of anesthetic regimens. Further studies are required to quantitatively evaluate the physiologic effects of drugs used and validate available monitoring modalities for use in a wide variety of reptiles.  相似文献