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1.
J Orthop Surg Res ; 19(1): 108, 2024 Feb 02.
Article in English | MEDLINE | ID: mdl-38303012

ABSTRACT

BACKGROUND: Artificial tendons may be an effective alternative to autologous and allogenic tendon grafts for repairing critically sized tendon defects. The goal of this study was to quantify the in vivo hindlimb biomechanics (ground contact pressure and sagittal-plane motion) during hopping gait of rabbits having a critically sized tendon defect of the tibialis cranialis and either with or without repair using an artificial tendon. METHODS: In five rabbits, the tibialis cranialis tendon of the left hindlimb was surgically replaced with a polyester, silicone-coated artificial tendon (PET-SI); five operated control rabbits underwent complete surgical excision of the biological tibialis cranialis tendon in the left hindlimb with no replacement (TE). RESULTS: At 8 weeks post-surgery, peak vertical ground contact force in the left hindlimb was statistically significantly less compared to baseline for the TE group (p = 0.0215). Statistical parametric mapping (SPM) analysis showed that, compared to baseline, the knee was significantly more extended during stance at 2 weeks post-surgery and during the swing phase of stride at 2 and 8 weeks post-surgery for the TE group (p < 0.05). Also, the ankle was significantly more plantarflexed during swing at 2 and 8 weeks postoperative for the TE group (p < 0.05). In contrast, there were no significant differences in the SPM analysis among timepoints in the PET-SI group for the knee or ankle. CONCLUSIONS: Our findings suggest that the artificial tibialis cranialis tendon effectively replaced the biomechanical function of the native tendon. Future studies should investigate (1) effects of artificial tendons on other (e.g., neuromuscular) tissues and systems and (2) biomechanical outcomes when there is a delay between tendon injury and artificial tendon implantation.


Subject(s)
Silicones , Tendon Injuries , Animals , Rabbits , Polyesters , Tendons/surgery , Ankle , Tendon Injuries/surgery , Biomechanical Phenomena
2.
J Biomech ; 151: 111520, 2023 04.
Article in English | MEDLINE | ID: mdl-36944293

ABSTRACT

Artificial tendons may be valuable clinical devices for replacing damaged or missing biological tendons. In this preliminary study, we quantified the effect of polyester-suture-based artificial tendons on movement biomechanics. New Zealand White rabbits underwent surgical replacement of either the Achilles (n = 2) or tibialis cranialis (TC, n = 2) biological tendons with artificial tendons. Once pre-surgery and weekly from 2 to 6 weeks post-surgery, we quantified hindlimb kinematics and ground contact pressures during the stance phase of hopping gait. Post-surgical movement biomechanics were either consistent or improved over time in both groups. However, the Achilles group had greater overall biomechanical and muscle deficits than the TC group. In the TC group, at 6 weeks post-surgery, foot angles were about 10° greater than those in healthy controls during the first 30 % of stance. At 6 weeks post-surgery, the Achilles group exhibited lesser (i.e., more dorsiflexed) ankle angles (minimum angle = 31.5 ± 9.4°) and vertical ground reaction forces (37.4 ± 2.6 %BW) during stance than those in healthy controls (65.0 ± 11.2° and 50.2 ± 8.3 %BW, respectively). Future studies are needed to quantify long-term biomechanical function with artificial tendons, the effect of artificial tendons on muscle function and structure, and the effect of formal rehabilitation.


Subject(s)
Achilles Tendon , Foot , Animals , Rabbits , Biomechanical Phenomena , Foot/physiology , Ankle , Gait/physiology , Achilles Tendon/physiology
3.
Am J Vet Res ; 83(7)2022 May 21.
Article in English | MEDLINE | ID: mdl-35930774

ABSTRACT

OBJECTIVE: To perform a qualitative analysis of the distribution of µ- and κ-opioid receptor mRNA in the forebrain and midbrain of budgerigars (Melopsittacus undulatus). SAMPLE: 8 brains of male budgerigars. PROCEDURES: Custom-made RNA hybridization probes (RNAscope; Advanced Cell Diagnostics Inc) were used for fluorescent in situ hybridization (FISH) assays performed on selected fresh frozen prepared sections of brain tissue to identify µ- and κ-opioid receptor mRNA. RESULTS: There was κ-opioid receptor mRNA present in the nucleus dorsomedialis posterior thalami, lateral striatum, mesopallium, tractus corticohabenularis et corticoseptalis, griseum et fibrosum, stratum griseum centrale, medial striatum, and area parahippocampalis. There was µ-opioid receptor mRNA present in the stratum griseum centrale, stratum opticum, dorsomedialis posterior thalami, area parahippocampalis, medial striatum, and nidopallium intermedium. CLINICAL RELEVANCE: Consistent with previous studies in pigeons and domestic chicks, κ-opioid receptors were more abundant than µ-opioid receptors in the samples of the present study. The results of this study may also help explain the hyperexcitability or lack of response that can occur with administration of pure µ-opioid receptor agonists, but not κ-opioid receptor agonists. This study was not quantitative, so further research should endeavor to compare the various regions of the brain using FISH technology.


Subject(s)
Melopsittacus , Receptors, Opioid, kappa , Animals , Brain , In Situ Hybridization, Fluorescence/veterinary , Male , RNA, Messenger/analysis , RNA, Messenger/genetics , Receptors, Opioid , Receptors, Opioid, kappa/genetics , Superior Colliculi/chemistry
4.
Bioengineering (Basel) ; 9(8)2022 Jul 27.
Article in English | MEDLINE | ID: mdl-36004873

ABSTRACT

Prosthetic limbs that are completely implanted within skin (i.e., endoprostheses) could permit direct, physical muscle-prosthesis attachment to restore more natural sensorimotor function to people with amputation. The objective of our study was to test, in a rabbit model, the feasibility of replacing the lost foot after hindlimb transtibial amputation by implanting a novel rigid foot-ankle endoprosthesis that is fully covered with skin. We first conducted a pilot, non-survival surgery in two rabbits to determine the maximum size of the skin flap that could be made from the biological foot-ankle. The skin flap size was used to determine the dimensions of the endoprosthesis foot segment. Rigid foot-ankle endoprosthesis prototypes were successfully implanted in three rabbits. The skin incisions healed over a period of approximately 1 month after surgery, with extensive fur regrowth by the pre-defined study endpoint of approximately 2 months post surgery. Upon gross inspection, the skin surrounding the endoprosthesis appeared normal, but a substantial subdermal fibrous capsule had formed around the endoprosthesis. Histology indicated that the structure and thickness of the skin layers (epidermis and dermis) were similar between the operated and non-operated limbs. A layer of subdermal connective tissue representing the fibrous capsule surrounded the endoprosthesis. In the operated limb of one rabbit, the subdermal connective tissue layer was approximately twice as thick as the skin on the medial (skin = 0.43 mm, subdermal = 0.84 mm), ventral (skin = 0.80 mm, subdermal = 1.47 mm), and lateral (skin = 0.76 mm, subdermal = 1.42 mm) aspects of the endoprosthesis. Our results successfully demonstrated the feasibility of implanting a fully skin-covered rigid foot-ankle endoprosthesis to replace the lost tibia-foot segment of the lower limb. Concerns include the fibrotic capsule which could limit the range of motion of jointed endoprostheses. Future studies include testing of endoprosthetics, as well as materials and pharmacologic agents that may suppress fibrous encapsulation.

5.
J Wildl Dis ; 58(3): 692-696, 2022 07 01.
Article in English | MEDLINE | ID: mdl-35704506

ABSTRACT

We describe necropsy lesions of three adult Yellow-rumped Warblers (Setophaga coronata) diagnosed with salmonellosis during a Salmonella enterica serovar Typhimurium outbreak. One warbler had filamentous organisms consistent with Macrorhabdus ornithogaster at the proventricular-ventricular isthmus. There is limited information on Macrorhabdus ornithogaster infections in wild North American birds.


Subject(s)
Mycoses , Salmonella Infections, Animal , Songbirds , Animals , Disease Outbreaks/veterinary , Mycoses/epidemiology , Mycoses/veterinary , North America , Saccharomycetales/pathogenicity , Salmonella Infections, Animal/epidemiology , Salmonella typhimurium , Songbirds/microbiology
6.
Ann Biomed Eng ; 49(3): 1012-1021, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33034786

ABSTRACT

Previous prostheses for replacing a missing limb following amputation must be worn externally on the body. This limits the extent to which prostheses could physically interface with biological tissues, such as muscles, to enhance functional recovery. The objectives of our study were to (1) test the feasibility of implanting a limb prosthesis, or endoprosthesis, entirely within living skin at the distal end of a residual limb, and (2) identify effective surgical and post-surgical care approaches for implanting endoprostheses in a rabbit model of hindlimb amputation. We iteratively designed, fabricated, and implanted unjointed endoprosthesis prototypes in six New Zealand White rabbits following amputation. In the first three rabbits, the skin failed to heal due to ishemia and dehiscence along the sutured incision. The skin of the final three subsequent rabbits successfully healed over the endoprotheses. Factors that contributed to successful outcomes included modifying the surgical incision to preserve vasculature; increasing the radii size on the endoprostheses to reduce skin stress; collecting radiographs pre-surgery to match the bone pin size to the medullary canal size; and ensuring post-operative bandage integrity. These results will support future work to test jointed endoprostheses that can be attached to muscles.


Subject(s)
Artificial Limbs , Plastic Surgery Procedures , Prosthesis Implantation , Amputation, Surgical , Animals , Feasibility Studies , Hindlimb/diagnostic imaging , Hindlimb/surgery , Male , Muscle, Skeletal/diagnostic imaging , Muscle, Skeletal/surgery , Prosthesis Design , Rabbits , Tibia/diagnostic imaging , Tibia/surgery , Weight-Bearing
7.
J Am Vet Med Assoc ; 257(8): 801-803, 2020 Oct 15.
Article in English | MEDLINE | ID: mdl-33021450

Subject(s)
Animals
8.
J Avian Med Surg ; 33(1): 29-37, 2019 03 01.
Article in English | MEDLINE | ID: mdl-31124609

ABSTRACT

To compare the bending strength of a locking plate (LP), nonlocking plate (NLP), and an external skeletal fixator intramedullary pin (ESF-IM) tie-in fixation applied by a dorsal approach in an avian humerus fracture model, 5 left humeri obtained from pigeon (Columba livia) cadavers were randomly assigned to each repair technique (n = 15). The ESF-IM group was repaired with a 0.062-inch intramedullary pin tied-in with two 0.035-inch positive profile transfixation pins using acrylic filled plastic tubing. The LP group was repaired with a dorsally applied titanium 1.6-mm screw 7-hole locking plate (1 bicortical and 2 monocortical screws in each segment). The NLP group was repaired with a dorsally applied 6-hole stainless steel 1.5-mm dynamic compression plate (all bicortical screws). All constructs were applied before complete ostectomy to allow perfect reconstruction. Constructs were cyclically tested nondestructively for 1000 cycles in four-point bending before being tested to failure. Outcome measures included stiffness, strength, and strain energy. All specimens cycled without failure. The ESF-IM specimens were significantly stiffer and stronger than the plated repair groups. Plated constructs had significantly higher strain energies than ESF-IM. LP and NLP were of equal stiffness, strength, and strain energies. This study demonstrated that bending biomechanical properties of the ESF-IM configuration were superior to those of the dorsal plate fixation. Exact properties of fixation required to facilitate avian fracture healing are largely unknown. Further study, including assessments of optimal plate position and configuration, and torsional and in vivo studies in avian species are warranted.


Subject(s)
Bone Plates/veterinary , Columbidae/injuries , Columbidae/surgery , Fracture Fixation/veterinary , Fractures, Bone/veterinary , Humerus/injuries , Analysis of Variance , Animals , Animals, Wild , Biomechanical Phenomena , Bone Nails/veterinary , Bone Plates/classification , Bone Plates/standards , Cadaver , Fracture Fixation/instrumentation , Fracture Fixation/methods , Fracture Healing , Fractures, Bone/surgery , Humerus/surgery , Random Allocation
9.
J Avian Med Surg ; 32(2): 102-108, 2018 06.
Article in English | MEDLINE | ID: mdl-29905104

ABSTRACT

Meloxicam is a nonsteroidal anti-inflammatory drug (NSAID) that has been used orally and intramuscularly in numerous avian species, but not studied to date, in African penguins ( Spheniscus demersus). The study describes the pharmacokinetic parameters of meloxicam after oral and intramuscular administration to African penguins. Several pilot studies were conducted initially where meloxicam (1, 0.5, and 0.25 mg/kg) was given intramuscularly to 4 birds, and orally (1 mg/kg) to 2 birds. Based on pilot study results, one group of 8 penguins was given meloxicam 0.5 mg/kg intramuscularly and one group of 8 penguins was given 1 mg/kg orally. Blood samples were collected at baseline and at 11 time intervals per group after administration of meloxicam. Meloxicam time to maximum plasma concentration (Tmax), maximum concentration (Cmax), and half-life (t1/2) after intramuscular administration were 1.00 hour, 8.03 µg/mL, and 31.87 hours, respectively, while oral administration produced a Tmax, Cmax, and t1/2 of 12.00 hours, 10.84 µg/mL, and 28.59 hours, respectively. Based on plasma meloxicam concentrations found to be therapeutic in other bird species and humans, the recommended dosage and frequency for African penguins is 1 mg/kg orally every 48 hours and 0.5 mg/kg intramuscularly every 24 hours. Further studies are needed to determine the multiple-dose pharmacokinetics of meloxicam in African penguins.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics , Birds/metabolism , Meloxicam/pharmacokinetics , Administration, Oral , Animals , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Anti-Inflammatory Agents, Non-Steroidal/blood , Area Under Curve , Biological Availability , Birds/blood , Endangered Species , Female , Injections, Intramuscular/veterinary , Male , Meloxicam/administration & dosage , Meloxicam/blood , Pilot Projects , Species Specificity
10.
J Avian Med Surg ; 31(2): 128-131, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28644084

ABSTRACT

Macrorhabdus ornithogaster is a yeast organism that infects multiple species of captive and wild birds. Diagnosis of infection in vivo has proven difficult historically, as shedding can be intermittent, and not all positive animals are clinically ill. We compared polymerase chain reaction (PCR) of cloacal swab samples and fecal Gram's stain (FGS) for diagnosis of active shedding of M ornithogaster in a captive flock of budgerigars ( Melopsittacus undulatus ). Of the 100 birds sampled, 57 (57%) were positive for M ornithogaster by PCR and 24 (24%) were positive for M ornithogaster by FGS. All FGS-tested birds also were positive on PCR. There was a significant association between the two methods, but the overall percent agreement for the two methods was only 67%. Based on these findings, cloacal swab PCR is more likely to diagnose the presence of M ornithogaster than FGS in budgerigars.


Subject(s)
Bird Diseases/diagnosis , Melopsittacus , Mycoses/veterinary , Yeasts/isolation & purification , Animals , Cloaca/microbiology , Mycoses/diagnosis , Mycoses/microbiology
11.
J Vet Diagn Invest ; 28(6): 763-769, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27698164

ABSTRACT

An organism reported in the early literature to be a rare cause of cervical lymphadenitis in guinea pigs, Streptobacillus moniliformis, has been reclassified as Caviibacter abscessus We describe a series of sequential cases of abscesses in guinea pigs that were presented to our clinic from which the only agent isolated was a unique, serum-requiring bacterium. Discrete colonies were not detected in 6.5% CO2 or anaerobically on routine primary isolation media containing up to 5% whole sheep blood, with and without cysteine, vitamin K, and hemin supplementation after 7 days of incubation at 37°C. Based on subsequently determined growth requirements, the organisms were best described as serum-requiring, aerotolerant anaerobes. Colonies were detectable within 24 h at 37°C in an anaerobic atmosphere on a mycoplasma agar-based medium containing 10% pig serum and reached 3 mm in diameter within 3-5 days. Microscopic appearance consisted of small gram-negative rods and coccobacilli with occasional filaments. However, in direct smears from clinical specimens and from weak or dysgonic growth on plates incubated under suboptimal growth conditions (e.g., in 6.5% CO2), irregular rods with occasional small bulbous forms or numerous long wavy filaments were observed. All of the isolates generated unique spectral profiles similar to that of C. abscessus when examined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Phylogenetic analysis of partial 16S rRNA gene sequences showed that the isolates were identical to each other and shared 99.9% sequence identity with C. abscessus.


Subject(s)
Abscess/veterinary , Fusobacteria/isolation & purification , Gram-Negative Bacterial Infections/veterinary , Guinea Pigs , Abscess/diagnosis , Abscess/microbiology , Animals , Diagnosis, Differential , Female , Fusobacteria/genetics , Gram-Negative Bacterial Infections/diagnosis , Gram-Negative Bacterial Infections/microbiology , Lymph Nodes/microbiology , Male , Neck , Pets , RNA, Ribosomal, 16S/genetics
13.
J Exot Pet Med ; 24(2): 164-171, 2015 Apr.
Article in English | MEDLINE | ID: mdl-32288683

ABSTRACT

Reproductive diseases commonly occur in backyard hens, and the underlying cause is usually different from that of commercial-production hens. Because backyard hens typically live longer, are usually provided an adequate diet, and have relatively more space than commercial hens, the most common causes of their reproductive disease include neoplasia, egg-related peritonitis, persistent right oviduct, and old age. Conversely, other reproductive diseases including vent trauma and depletion of calcium are rarely diagnosed.

14.
J Am Vet Med Assoc ; 244(8): 950-5, 2014 Apr 15.
Article in English | MEDLINE | ID: mdl-24697772

ABSTRACT

OBJECTIVE: To describe morbidity, function, outcome, and owner satisfaction associated with limb amputation in domestic rabbits. DESIGN: Retrospective case series. ANIMALS: 34 client-owned domestic rabbits. PROCEDURES: Medical records of domestic rabbits undergoing limb amputation for any cause between 2000 and 2009 were reviewed. The Kaplan-Meier method was used to estimate survival rate and median survival time, and variables were analyzed for relationship to risk of morbidity resulting in euthanasia and to outcome (survival vs nonsurvival [death or euthanasia]). Owners were interviewed to determine satisfaction with outcome of the procedure. RESULTS: 28 rabbits underwent pelvic limb amputation, and 6 underwent thoracic limb amputation. At the last follow-up, 18 rabbits were dead, 9 were alive, and 7 were lost to follow-up. Median overall survival time was 720 days (range, 4 to 3,250 days). Acute and delayed or chronic complications were observed in 22 of 34 and 19 of 32 rabbits, respectively, most commonly difficulty ambulating, hygiene issues, and pododermatitis (cutaneous ulcers at the hock). Six rabbits were euthanized because of complications at a median of 104 days (range, 4 to 399 days) after surgery. Risk of morbidity resulting in euthanasia increased with heavier body weight and concurrent disease affecting ambulation at the time of amputation. Weight, age, and pododermatitis at the time of amputation were significantly negatively associated with survival time. Thirty-one (91%) owners were satisfied with the outcome. CONCLUSIONS AND CLINICAL RELEVANCE: Although limb amputation was tolerated by most rabbits and most owners were satisfied, complications resulted in death in 6 of 34 (18%) rabbits, and 19 of 32 (59%) developed chronic complications. Amputation in heavy rabbits or those with concurrent pododermatitis, musculoskeletal disease, or neurologic disease should be considered carefully. Because of the small sample size and retrospective nature of this study, results should be interpreted as exploratory and hypothesis generating.


Subject(s)
Amputation, Surgical/veterinary , Rabbits , Animals , Female , Male , Retrospective Studies , Risk Factors , Time Factors , Treatment Outcome
15.
J Vet Diagn Invest ; 23(1): 99-104, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21217036

ABSTRACT

Isolates of gram-negative anaerobic bacteria from reptiles have only occasionally been identified to the genus and species level in the veterinary medical literature. In particular, reports identifying Porphyromonas spp. from infections in reptiles are scarce. The present report describes unique Porphyromonas isolates obtained from necrosuppurative infections in central bearded dragons (Pogona vitticeps). The isolates grew in the presence of oxygen, were strongly hemolytic, and did not produce detectable black, iron porphyrin pigment. Biochemical identification kit numeric biocodes gave high but unreliable probabilities (>99.9%) for identification as Porphyromonas gingivalis. Partial 16S ribosomal RNA gene sequences of the isolates were identical to each other and shared 91% identity with those of Porphyromonas gulae. The isolates may represent a new reptile-associated Porphyromonas species.


Subject(s)
Bacteroidaceae Infections/veterinary , Lizards/microbiology , Porphyromonas/isolation & purification , Animals , Anti-Bacterial Agents/therapeutic use , Bacteroidaceae Infections/drug therapy , Bacteroidaceae Infections/microbiology , Base Sequence , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Fatal Outcome , Female , Histocytochemistry/veterinary , Male , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction/veterinary , Porphyromonas/genetics , RNA, Ribosomal, 16S/chemistry , RNA, Ribosomal, 16S/genetics , Sequence Alignment
16.
J Vet Diagn Invest ; 22(2): 316-20, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20224102

ABSTRACT

A metastatic gastric neuroendocrine carcinoma in a 2.5-year-old inland bearded dragon (Pogona vitticeps) with a chronic history of anorexia, weight loss, depression, and acute melena is described. Histologic examination of the gastric mass revealed a densely cellular tumor arranged in nests and occasional rosettes of hyperchromatic cells with oval to spindle-shaped nuclei and minimal cytoplasm; the tumor was supported by a moderate fibrovascular stroma. Similar cells invaded through the gastric mucosa, and there were multiple hepatic metastases. The neoplastic cells were weakly immunopositive for neuron-specific enolase and moderately positive for somatostatin but were negative for chromogranin AB and gastrin. Ultrastructural studies revealed scattered neurosecretory granules in the neoplastic cells, confirming the diagnosis of a neuroendocrine carcinoma.


Subject(s)
Carcinoma, Neuroendocrine/veterinary , Lizards , Stomach Neoplasms/veterinary , Animals , Carcinoma, Neuroendocrine/pathology , Female , Liver Neoplasms/secondary , Liver Neoplasms/veterinary , Stomach Neoplasms/pathology
17.
Avian Pathol ; 38(5): 413-7, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19937528

ABSTRACT

Consensus polymerase chain reaction was used to identify a novel adenovirus from two psittacine birds: a plum-headed parakeet (Psittacula cyanocephala) with lethargy, weight loss, and marked leukocytosis; and an umbrella cockatoo (Cacatua alba) with lethargy, weight loss, and feather abnormalities. Phylogenetic and comparative sequence analysis suggested that this virus is a member of the genus Siadenovirus, and is here termed psittacine adenovirus 2. This extends the characterized adenoviruses of psittacine birds beyond Aviadenovirus to include the genus Siadenovirus. Identification and further study of adenoviral types and species will provide useful diagnostic, prognostic, and epidemiologic information for the clinician. Like other known members of the genus Siadenovirus, Psittacine adenovirus 2 is AT-rich over the region sequenced, and it is hypothesized that this may be associated with shorter host-virus evolutionary association.


Subject(s)
Adenoviridae Infections/veterinary , Bird Diseases/virology , Cockatoos , Parakeets , Siadenovirus/physiology , AT Rich Sequence , Adenoviridae Infections/genetics , Adenoviridae Infections/physiopathology , Adenoviridae Infections/virology , Animals , Aviadenovirus/genetics , Biological Evolution , Bird Diseases/genetics , Bird Diseases/physiopathology , DNA, Viral , Feathers , Host-Pathogen Interactions/genetics , Lethargy , Lymphocytosis , Phylogeny , Siadenovirus/isolation & purification , Weight Loss
18.
Am J Vet Res ; 70(8): 945-9, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19645574

ABSTRACT

OBJECTIVE: To evaluate the effect of IV administration of tramadol hydrochloride on the minimum alveolar concentration of isoflurane (ISOMAC) that prevented purposeful movement of rabbits in response to a noxious stimulus. ANIMALS: Six 6- to 12-month-old female New Zealand White rabbits. PROCEDURES: Anesthesia was induced and maintained with isoflurane in oxygen. A baseline ISOMAC was determined by clamping a pedal digit with sponge forceps until gross purposeful movement was detected or a period of 60 seconds elapsed. Subsequently, tramadol (4.4 mg/kg) was administered IV and the posttreatment ISOMAC (ISOMAC(T)) was measured. RESULTS: Mean +/- SD ISOMAC and ISOMAC(T) values were 2.33 +/- 0.13% and 2.12 +/- 0.17%, respectively. The ISOMAC value decreased by 9 +/- 4% after tramadol was administered. Plasma tramadol and its major metabolite (M1) concentrations at the time of ISOMAC(T) determination varied widely (ranges, 181 to 636 ng/mL and 32 to 61 ng/mL, respectively). Intervals to determination of ISOMAC(T) and plasma tramadol and M1 concentrations were not correlated with percentage change in the ISOMAC. Heart rate decreased significantly immediately after tramadol administration but by 10 minutes afterward was not different from the pretreatment value. Systolic arterial blood pressure decreased to approximately 60 mm Hg for approximately 5 minutes in 3 rabbits after tramadol administration. No adverse effects were detected. CONCLUSIONS AND CLINICAL RELEVANCE: As administered, tramadol had a significant but clinically unimportant effect on the ISOMAC in rabbits. Higher doses of tramadol may provide clinically important reductions but may result in a greater degree of cardiovascular depression.


Subject(s)
Analgesics, Opioid/pharmacology , Anesthetics, Inhalation/metabolism , Isoflurane/blood , Tramadol/pharmacology , Analgesics, Opioid/administration & dosage , Animals , Blood Pressure/drug effects , Female , Heart Rate/drug effects , Physical Stimulation , Rabbits , Time Factors , Tramadol/administration & dosage , Tramadol/blood
19.
J Vet Diagn Invest ; 20(5): 656-60, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18776105

ABSTRACT

A 10-year-old, intact, female yellow-naped Amazon parrot was examined because of anemia, lymphocytic leukocytosis, regurgitation, and weight loss. A positive fecal occult blood and monoclonal globulinopathy were present. A distended proventriculus and diffusely thickened loops of small intestine with irregular luminal surfaces were identified with contrast radiography and contrast computed tomography. A micro positron emission tomography scan was performed with (18)F-fluorodeoxyglucose. Diffuse intestinal T-cell lymphosarcoma was diagnosed based on histopathology and immunohistochemistry of full thickness small intestinal biopsies. The patient was treated with a multidrug chemotherapy protocol with little to no effect. Euthanasia was elected, and intestinal lymphosarcoma was confirmed on histopathology of necropsy intestinal samples; no other organs demonstrated neoplastic infiltration. To the authors' knowledge, no reports are currently available detailing the clinical presentation or diagnosis of diffuse intestinal T-cell lymphosarcoma in any avian species.


Subject(s)
Bird Diseases/pathology , Intestinal Neoplasms/veterinary , Lymphoma, Non-Hodgkin/veterinary , Lymphoma, T-Cell, Cutaneous/veterinary , Animals , Euthanasia , Intestinal Neoplasms/diagnostic imaging , Intestinal Neoplasms/pathology , Lymphoma, Non-Hodgkin/diagnostic imaging , Lymphoma, Non-Hodgkin/pathology , Lymphoma, T-Cell, Cutaneous/diagnostic imaging , Lymphoma, T-Cell, Cutaneous/pathology , Parrots , Positron-Emission Tomography/veterinary , Radiography
20.
Am J Vet Res ; 69(8): 979-82, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18672959

ABSTRACT

OBJECTIVE: To determine the pharmacokinetics of an orally administered dose of tramadol in domestic rabbits (Oryctolagus cuniculus). ANIMALS: 6 healthy adult sexually intact female New Zealand White rabbits. PROCEDURES: Physical examinations and plasma biochemical analyses were performed to ensure rabbits were healthy prior to the experiment. Rabbits were anesthetized with isoflurane, and IV catheters were placed in a medial saphenous or jugular vein for collection of blood samples. One blood sample was collected before treatment with tramadol. Rabbits were allowed to recover from anesthesia a minimum of 1 hour before treatment. Then, tramadol (11 mg/kg, PO) was administered once, and blood samples were collected at various time points up to 360 minutes after administration. Blood samples were analyzed with high-performance liquid chromatography to determine plasma concentrations of tramadol and its major metabolite (O-desmethyltramadol). RESULTS: No adverse effects were detected after oral administration of tramadol to rabbits. Mean +/- SD half-life of tramadol after administration was 145.4 +/- 81.0 minutes; mean +/- SD maximum plasma concentration was 135.3 +/- 89.1 ng/mL. CONCLUSIONS AND CLINICAL RELEVANCE: Although the dose of tramadol required to provide analgesia in rabbits is unknown, the dose administered in the study reported here did not reach a plasma concentration of tramadol or O-desmethyltramadol that would provide sufficient analgesia in humans for clinically acceptable periods. Many factors may influence absorption of orally administered tramadol in rabbits.


Subject(s)
Tramadol/pharmacokinetics , Analgesia , Animals , Chromatography, High Pressure Liquid , Female , Humans , Narcotics/blood , Narcotics/pharmacokinetics , Rabbits , Tramadol/analogs & derivatives , Tramadol/blood
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