bluuebunny/crossref_metadata_2025 huggingface dataset:
Bispectral index, spectral edge frequency 95%, and median frequency recorded for various concentrations of isoflurane and sevoflurane in pigs
Authors: Martín-Cancho María F. , Lima Juan R. , Luis Laura , Crisóstomo Verónica , Ezquerra Luis J. , Carrasco María S. , Usón-Gargallo Jesús
Published: January 2006

Objective—To evaluate bispectral index (BIS), spectral
edge frequency 95% (SEF), and median frequency
(MED) in relation to a visual analogue scale (VAS)
as indicators of anesthetic depth for various concentrations
of sevoflurane and isoflurane in pigs.

Animals—32 pigs.

Procedure—Pigs were randomly allocated to 8 groups
(4 pigs/group). An electroencephalogram (EEG) was
recorded in each conscious pig. Pigs were then anesthetized
by use of sevoflurane (n = 16) or isoflurane
(16). Agents were administered in oxygen at minimum
alveolar concentrations (MACs) of 1, 1.25, 1.5, and 1.75
MAC in a randomized order. End-tidal sevoflurane and
isoflurane concentrations were maintained for 30 minutes,
after which an EEG was recorded for 5 minutes;
BIS, SEF, and MED were then calculated. Anesthetic
depth was evaluated by use of the VAS. Cardiovascular
and EEG responses to nociceptive stimuli were evaluated
for each anesthetic agent.

Results—BIS decreased significantly for the various
concentrations of each anesthetic. At equivalent
MACs, BIS values were significantly higher during
sevoflurane-induced anesthesia than during isoflurane-
induced anesthesia. Values of MED and SEF
decreased significantly from basal values to 1 MAC of
sevoflurane and isoflurane. For both agents, there
was good correlation between VAS scores and BIS
values and between VAS scores and SEF values.

Conclusions and Clinical Relevance—BIS was useful
for predicting changes in anesthetic depth at clinical
dosages of inhalant anesthetics. Values of BIS,
SEF, and MED were significantly higher during anesthesia
induced by administration of sevoflurane than
during anesthesia induced by administration of isoflurance
at equivalent MACs. (Am J Vet Res 2003;64:866–873)
Effect of an adenoviral vector that expresses the canine p53 gene on cell growth of canine osteosarcoma and mammary adenocarcinoma cell lines
Authors: Yazawa Mitsuhiro , Setoguchi Asuka , Hong Sung-Hyeok , Uyama Rina , Nakagawa Takayuki , Kanaya Noriko , Nishimura Ryohei , Sasaki Nobuo , Masuda Kenichi , Ohno Koichi , Tsujimoto Hajime
Published: January 2006

Objective—To generate an adenoviral vector that expressed the caninep53gene and investigate its growth-inhibiting effect on canine osteosarcoma and mammary adenocarcinoma cell lines.

Sample Population—2 canine osteosarcoma cell lines (HOS, OOS) and 3 canine mammary adenocarcinoma cell lines (CHMp, CIPm, and CNMm).

Procedure—An adenoviral vector that expressed the caninep53gene (AxCA-cp53) was generated.p53gene expression was examined by use of reverse transcription (RT)-polymerase chain reaction (PCR) assay and immunohistochemistry. Susceptibility of cell lines to the adenoviral vector was determined by infection with an adenoviral vector that expresses β-galactosidase (AxCA-LacZ) and 3-indolyl-β-D-galactopyranoside staining. Growth inhibitory effects were examined by monitoring the numbers of cells after infection with mock (PBS) solution, AxCA-LacZ, or AxCA-cp53. The DNA contents per cell were measured by flow cytometry analysis. Apoptotic DNA fragmentation was detected by use of a terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay.

Results—AxCA-cp53-derivedp53gene mRNA and P53 protein were detected by RT-PCR analysis and immunohistochemistry, respectively. Multiplicity of infection at which 50% of cells had positive 3-indolyl- β-D-galactopyranoside staining results ranged from 10 to 50. AxCA-cp53 induced growth inhibition in a dosedependent manner. Arrest of the G1-phase population and apoptotic DNA fragmentation were observed in cells infected with AxCA-cp53.

Conclusions and Clinical Relevance—AxCA-cp53 inhibits cell growth via induction of cell cycle arrest and apoptosis in canine osteosarcoma and mammary adenocarcinoma cell lines that lack a functionalp53gene. AxCA-cp53 may be useful to target thep53gene in the treatment of dogs with tumors. (Am J Vet Res2003;64:880–888)
Population pharmacokinetics of marbofloxacin in aqueous humor after intravenous administration in dogs
Authors: Regnier Alain , Concordet Didier , Schneider Marc , Boisramé Bernard , Toutain Pierre-Louis
Published: January 2006

Objective—To evaluate, by use of population pharmacokinetics,
the disposition of marbofloxacin in the
aqueous humor after IV administration in dogs and
identify its potential usefulness in the prophylaxis and
treatment of intraocular infection.

Animals—63 dogs.

Methods—Dogs received a single dose of marbofloxacin
(2 mg · kg–1, IV) at various time intervals
before cataract surgery. Aqueous humor and blood
samples were collected at the beginning of surgery.
Marbofloxacin concentrations were measured by
high-pressure liquid chromatography. Data were analyzed
with a nonlinear mixed-effect model and, by use
of population pharmacokinetic parameters, the time
course of aqueous humor concentration was simulated
for single doses of 3, 4, and 5.5 mg · kg–1IV.
Pharmacodynamic surrogate markers and measured
aqueous humor concentrations were used to predict
in vivo antimicrobial activity.

Results—A maximum marbofloxacin concentration
of 0.41 ± 0.17 µg·mL–1 was reached in the aqueous
humor 3.5 hours after IV administration. In the postdistributive
phase, marbofloxacin disappeared from
aqueous humor with a half-life of 780 minutes. The
percentage penetration into the aqueous humor was
38%. Predictors of antimicrobial effects of marbofloxacin
(2 mg · kg–1, IV) indicated that growth of the
enterobacteriaceae and certain staphylococcal
species would be inhibited in the aqueous humor.
Marbofloxacin administered IV at a dose of
5.5 mg · kg–1 would be predicted to inhibit growth of
Pseudomonas aeruginosa and all strains of staphylococci
but would not eradicate streptococcal infections.

Conclusions and Clinical Relevance—Marbofloxacin
administered IV can penetrate the aqueous
humor of canine eyes and may be suitable for prophylaxis
or treatment of certain anterior chamber
infections. (Am J Vet Res 2003;64:889–893)
Effect of variable-dose propofol alone and in combination with two fixed doses of ketamine for total intravenous anesthesia in cats
Authors: Ilkiw Jan E. , Pascoe Peter J. , Tripp Linda D.
Published: January 2006

Objective—To determine the minimum infusion rate (MIR50) for propofol alone and in combination with ketamine required to attenuate reflexes commonly used in the assessment of anesthetic depth in cats.

Animals—6 cats.

Procedure—Propofol infusion started at 0.05 to 0.1 mg/kg/min for propofol alone or 0.025 mg/kg/min for propofol and ketamine (low-dose [LD] constant rate infusion [CRI] of 23 µg/kg/min or high-dose [HD] CRI of 46 µg/kg/min), and after 15 minutes, responses of different reflexes were tested. Following a response, the propofol dose was increased by 0.05 mg/kg/min for propofol alone or 0.025 mg/kg/min for propofol and ketamine, and after 15 minutes, reflexes were retested.

Results—The MIR50for propofol alone required to attenuate blinking in response to touching the medial canthus or eyelashes; swallowing in response to placement of a finger or laryngoscope in the pharynx; and to toe pinch, tetanus, and tail-clamp stimuli were determined. Addition of LD ketamine to propofol significantly decreased MIR50, compared with propofol alone, for medial canthus, eyelash, finger, toe pinch, and tetanus stimuli but did not change those for laryngoscope or tail-clamp stimuli. Addition of HD ketamine to propofol significantly decreased MIR50, compared with propofol alone, for medial canthus, eyelash, toe pinch, tetanus, and tail-clamp stimuli but did not change finger or laryngoscope responses.

Conclusions and Clinical Relevance—Propofol alone or combined with ketamine may be used for total IV anesthesia in healthy cats at the infusion rates determined in this study for attenuation of specific reflex activity. (Am J Vet Res2003;64:907–912)
Correlation of helical and incremental high-resolution thin-section computed tomographic imaging with histomorphometric quantitative evaluation of lungs in dogs
Authors: Morandi Federica , Mattoon John S. , Lakritz Jeffrey , Turk James R. , Wisner Erik R.
Published: January 2006

Objective—To develop protocols for helical computed tomography (CT) and axial high-resolution CT (HRCT) of lungs and correlate densitometric CT values with morphometric and histologic data for normal pulmonary tissue in dogs.

Animals—8 healthy adult dogs.

Procedure—2 dogs were used to establish a protocol for helical CT and HRCT of lungs. Six dogs were used to acquire densitometric CT data regarding normal lungs. After the dogs were euthanatized, their lungs were fixed and sampled for morphometric and histologic evaluation. Four CT acquisitions were compared by means of pairedttests.

Results—For normal lung tissue of dogs, mean densitometric CT value obtained during helical CT scans reconstructed in a sharp algorithm was -846 Hounsfield units. Values obtained via helical CT or HRCT acquisitions and reconstructed with sharp or standard algorithms did not differ significantly. Morphometric analysis was used to determine the proportion of lung parenchymal (82%) and nonparenchymal tissue (18%). Alveolar size, estimated by mean linear intercept, was approximately 172 µm, and alveolar surface area-to-volume ratio was 0.024 to 0.026 µm–1. Histologic evaluation confirmed the presence of normal lung tissue.

Conclusions and Clinical Relevance—Correlation of densitometric CT data with morphometric and histologic findings and the establishment of helical CT and HRCT protocols were attained; clinical use of this information may facilitate investigation of pulmonary disease in dogs. Sharp helical CT acquisitions were preferred because of better lung parenchyma detail and rapid image acquisitions, compared with HRCT. (Am J Vet Res2003;64:935–944)
Distribution of Escherichia coli O157:H7 within and among cattle operations in pasture-based agricultural areas
Authors: Renter David G. , Sargeant Jan M. , Hungerford Laura L.
Published: January 2006

Objective—To determine the distribution ofEscherichia coliO157:H7 in pasture-based cattle production areas.

Sample Population—Two 100-km2agricultural areas consisting of 207 pasture, 14 beef-confinement, and 3 dairy locations within 24 cattle operations.

Procedure—13,726 samples from cattle, wildlife, and water sources were obtained during an 11-month period.Escherichia coliO157:H7 was identified by use of culture and polymerase chain reaction assays and characterized by pulsed-field gel electrophoresis (PFGE).

Results—Odds of recoveringE coliO157:H7 from feeder-aged cattle were > 4 times the odds for cowcalf or dairy cattle. There was no difference in prevalence for pastured versus confined cattle after controlling for production age group. Number of samples collected (37 to 4,829), samples that yieldedE coliO157:H7 (0 to 53), and PFGE subtypes (0 to 48) for each operation varied and were highly correlated. Although most PFGE subtypes were only detected once, 17 subtypes were detected on more than 1 operation. Ten of 12 operations at whichE coliO157:H7 was detected had at least 1 subtype that also was detected on another operation. We did not detect differences in the probability of having the same subtype for adjacent operations, nonadjacent operations in the same study area, or operations in the other study area.

Conclusions and Clinical Relevance—Strategies aimed at controllingE coliO157:H7 and specific subtypes should account for the widespread distribution and higher prevalence in feeder-aged cattle regardless of production environment and the fact that adjacent and distant cattle operations can have similar subtypes. (Am J Vet Res2004;65:1367–1376)
Effects of ischemia and the cyclooxygenase inhibitor flunixin on in vitro passage of lipopolysaccharide across equine jejunum
Authors: Tomlinson Julia E. , Blikslager Anthony T.
Published: January 2006

Objective—To determine whether ischemia and flunixin affect in vitro lipopolysaccharide (LPS) absorption in samples of the jejunum of horses.

Animals—12 horses.

Procedure—Horses were anesthetized, a midline celiotomy was performed, and the jejunum was located. Two 30-cm sections of jejunum (60 cm apart) were selected. One segment was designated as control tissue; ischemia was induced in the other segment for 120 minutes. Horses were then euthanatized. Mucosa from each jejunal segment was mounted on Ussing chambers and treated with or without flunixin. Tissues from 6 horses were used to assess permeability to radiolabeled LPS; mucosal samples from the remaining 6 horses were incubated with fluorescent-labeled LPS (FITC-LPS) and examined histologically. Production of tumor necrosis factor-α (TNF-α) and production of LPS-binding protein (LBP) were assessed as indicators of mucosal response to LPS.

Results—Ischemia significantly increased mucosal permeability to LPS, but by 180 minutes, the mucosa was not more permeable than control tissue. Flunixin treatment adversely affected intestinal barrier function throughout the experiment but did not result in increased mucosal permeability to LPS. Compared with control tissues, LBP production was increased by ischemia and reduced by exposure to LPS. In ischemic tissue, FITC-LPS entered the lamina propria but TNF-α was produced on the mucosal side only, indicating little response to the absorbed LPS.

Conclusions and Clinical Relevance—Ischemia increased LPS passage across equine jejunal mucosa. Flunixin delayed mucosal recovery but did not exacerbate LPS absorption. Evaluation of the clinical importance of flunixin-associated delayed mucosal recovery requires further in vivo investigation. (Am J Vet Res2004;65:1377–1383)
Effect of meloxicam and carprofen on renal function when administered to healthy dogs prior to anesthesia and painful stimulation
Authors: Crandell Dawn E. , Mathews Karol A. , Dyson Doris H.
Published: January 2006

Objective—To determine whether administration of the nonsteroidal anti-inflammatory drugs meloxicam or carprofen to healthy dogs that were subsequently anesthetized and subjected to painful electrical stimulation has adverse effects on renal function as measured by glomerular filtration rate (GFR) and evaluation of serum concentrations of urea and creatinine.

Animals—6 male and 6 female healthy young-adult Beagles.

Procedure—A study was conducted in accordance with a randomized crossover Latin-square design. One of 3 treatments (saline [0.9% NaCl] solution, 0.2 mg of meloxicam/kg, or 4.0 mg of carprofen/kg) was administered IV 1 hour before anesthesia was induced by use of drugs in accordance with a standard anesthetic protocol (butorphanol tartrate and acepromazine maleate as preanesthetic medications, ketamine hydrochloride and diazepam for induction, and maintenance with isoflurane). Anesthetized dogs were subjected to intermittent electrical stimulation for 30 minutes. Direct, mean arterial blood pressure; heart rate; and respiratory rate were monitored. End-tidal isoflurane concentration was maintained at 1.5 times the minimum alveolar concentration. The GFR, as measured by plasma clearance of 99mTc-diethylenetriaminepentaacetic acid, and serum concentrations of serum and creatinine were determined 24 hours after induction of anesthesia.

Results—Neither meloxicam nor carprofen significantly affected GFR or serum concentrations of urea and creatinine, compared with values for the saline treatment.

Conclusions and Clinical Relevance—When administered 1 hour before onset of anesthesia and painful electrical stimulation, meloxicam or carprofen did not cause clinically important alterations of renal function in young healthy dogs. (Am J Vet Res2004;65:1384–1390)
Effect of a commercial anion dietary supplement on acid-base balance, urine volume, and urinary ion excretion in male goats fed oat or grass hay diets
Authors: Stratton-Phelps Meri , House John K.
Published: January 2006

Objective—To determine whether feeding a commercial anionic dietary supplement as a urinary acidifier to male goats may be useful for management of urolithiasis.

Animals—8 adult sexually intact male Toggenburg, Saanen, and Nubian goats.

Procedure—Goats were randomly assigned by age-, breed-, and weight-matched pairs to an oat or grass hay diet that was fed for 12 days. On days 13 to 14 (early sample collection time before supplementation), measurements were made of blood and urine sodium, potassium, calcium, magnesium, chloride, phosphorus, and sulfur concentrations; blood and urine pH; urine production; and water consumption. During the next 28 days, the anionic dietary supplement was added to the oat and grass hay diets to achieve a dietary cation-anion difference of 0 mEq/100g of dry matter. Blood and urine samples were analyzed during dietary supplementation on days 12 to 13 (middle sample collection time) and 27 to 28 (late sample collection time).

Results—Blood bicarbonate, pH, and urine pH of goats fed grass hay and goats fed oat hay were significantly decreased during the middle and late sample collection times, compared with the early sample collection time. Water consumption and urine production in all goats increased significantly during the late sample collection time, compared with the early sample collection time.

Conclusions and Clinical Relevance—The anionic dietary supplement used in our study increases urine volume, alters urine ion concentrations, and is an efficacious urinary acidifier in goats. Goats treated with prolonged anionic dietary supplementation should be monitored for secondary osteoporosis from chronic urinary calcium loss. (Am J Vet Res2004;65:1391–1397)
Evaluation of environmental and management-related risk factors associated with chronic mastitis in sows
Authors: Hultén Fredrik , Persson Arne , Eliasson-Selling Lena , Heldmer Eva , Lindberg Maria , Sjögren Urban , Kugelberg Christina , Ehlorsson Carl-Johan
Published: January 2006

Objective—To evaluate environmental and management-related risk factors associated with chronic
mastitis in sows.

Animals—1,254 sows from 76 herds.

Procedure—Prevalence of chronic mastitis was
determined by a veterinarian who performed clinical
examinations at the time of weaning and approximately
1 week later in a sample of the sow population
on each farm. Information concerning environmental
factors and management practices was collected. In
addition, the herd veterinarian made an assessment
of the farmer's skills in swine production.

Results—Use of partly slatted floors in the farrowing
pens, use of disinfectants between batches in the farrowing
and breeding areas, feeding lactating sows
whey, and avoiding cutting or grinding of the piglets'
teeth were significantly associated with a decreased
risk of chronic mastitis. A high hygienic standard on
the farm, as determined by the herd veterinarian, was
associated with a significant reduction in the prevalence
of mastitis.

Conclusions and Clinical Relevance—Chronic mastitis
in sows is a common disease that has a negative
influence on productivity. Results indicate that certain
management practices and environmental factors
influenced the development of mastitis, which may
contribute to the development of methods useful for
controlling the disease. (Am J Vet Res
2004;65:1398–1403)
Comparison of inhibitory effects of glucosamine and mannosamine on bovine articular cartilage degradation in vitro
Authors: Mello David M. , Nielsen Brian D. , Peters Tonia L. , Caron John P. , Orth Michael W.
Published: January 2006

Objective—To compare the inhibitory effects of glucosamine and mannosamine on articular cartilage degradation and the effects on chondrocyte viability in vitro.

Sample Population—Bovine articular cartilage explants.

Procedures—Explants were cultured in commercial medium for 48 hours. Cartilage was exposed to medium containing 10% fetal bovine serum, 10 µg of lipopolysaccharide/mL, and 0.5, 1.0, 2.5, 5.0, and 10.0 mg of glucosamine or mannosamine/mL for 24 hours. Nitric oxide (NO) production (nitrite concentration) and proteoglycan (PG) release (PG concentration) in media were measured . Cartilage extracts were analyzed via zymography to detect gelatinolytic activity. At the end of the experiment, explants were assessed for chondrocyte viability.

Results—Addition of lipopolysaccharide resulted in increased NO production and PG release, but no increase in gelatinolytic activity, compared with controls. Glucosamine and mannosamine at concentrations as low as 0.5 mg/mL inhibited NO production. Glucosamine inhibited PG release at a minimum concentration of 1.0 mg/mL, whereas mannosamine inhibited PG release at a concentration of 0.5 mg/mL. Concentrations of glucosamine ≤ 5.0 mg/mL did not adversely affect chondrocyte viability; however, at a concentration of 10.0 mg/mL, cell death was evident. Mannosamine had a toxic effect at a concentration of 5.0 mg/mL and was associated with pronounced chondrocyte death at a concentration of 10.0 mg/mL.

Conclusions and Clinical Relevance—Glucosamine and mannosamine inhibit selected indices of bovine articular cartilage degradation at concentrations that do not affect chondrocyte viability. The potential for cytotoxic effects at higher concentrations underscores the importance of establishing appropriate dosage regimens for these aminomonosaccharides. (Am J Vet Res2004;65:1440–1445)
Assessment of the ability of Malassezia pachydermatis to stimulate proliferation of canine keratinocytes in vitro
Authors: Chen Tai-An , Halliwell Richard E. W. , Shaw Darren J. , Hill Peter B.
Published: January 2006

Objective—To investigate the direct interaction between canine keratinocytes and liveMalassezia pachydermatisand thereby determine the role of these organisms in the pathogenesis of epidermal hyperplasia associated withMalasseziadermatitis in dogs.

Sample population—Primary canine keratinocyte cultures established from skin samples obtained from clinically normal dogs.

Procedure—The proliferative response of keratinocytes co-cultured withMalasseziaorganisms for 1, 2, or 3 days was assessed by use of direct manual counting (to determine the number of keratinocytes in both the monolayer and the medium) and immunohistochemical staining techniques involving antibodies against proliferating cell nuclear antigen (PCNA) and another cellular proliferation marker, Ki-67. The potential cytotoxic effect ofMalasseziaorganisms was investigated by use of an apoptosis detection kit to label keratinocytes co-cultured withM pachydermatisthat underwent apoptosis.

Results—No stimulatory effect ofMalasseziaorganisms on canine keratinocyte proliferation was detected via cell counting and immunohistochemical techniques. However, there was a significant increase in dead keratinocytes in the medium with increasing numbers ofMalasseziaorganisms in the co-culture. More apoptotic cells were observed in keratinocyte monolayers co-cultured with high numbers ofM pachydermatisthan there were in monolayers cultured withoutMalasseziaorganisms, and the number increased after prolonged incubation.

Conclusions and Clinical Relevance—M pachydermatisdid not stimulate canine keratinocyte proliferation in vitro. The results suggested that the epidermal hyperplasia observed in dogs withMalasseziadermatitis is unlikely to be caused by a direct effect of the organism on the keratinocyte cell cycle, but is likely to involve other mechanisms.Am J Vet Res(2004;65:787–796)
Myoelectric activity in the intestines of healthy dairy cows during the recovery period after implantation of permanent electrodes
Authors: Meylan Mireille , Eicher Richard , Zulauf Marc , Steiner Adrian
Published: January 2006

Objective—To describe myoelectric patterns in the intestines of cows after electrode implantation.

Animals—7 lactating Simmental-Red Holstein cows.

Procedure—Cows were implanted with 7 pairs of bipolar silver electrodes (1 each in the ileum, cecum, and proximal loop of the ascending colon (PLAC) and 4 in the spiral colon). Myoelectric activity was monitored during 10 periods within the first 3 weeks after surgery. Recordings from the first 2 weeks were compared with recordings from the third week, which was considered a steady-state condition.

Results—Significant changes over time were detected for 18 of 57 variables, including 3 variables describing myoelectric activity of the ileum, 6 variables of the cecum, 6 variables of the PLAC, and 3 variables of the spiral colon. Compared with values for the steadystate condition, 16 variables differed significantly for the 14-day period after surgery (7 variables until day 11, 2 variables until day 8, 4 variables until day 5, 1 variable until day 3, and 2 variables until day 2 after electrode implantation). None of the variables had significant changes that lasted only 1 day after surgery.

Conclusions and Clinical Relevance—Significant changes were observed for several variables of myoelectric activity in all intestinal segments until as late as 11 days after electrode implantation, whereas a steady-state condition was reached 14 days after surgery. Effects of drugs, manipulations, or nutrition regimens on myoelectric activity of the bovine digestive tract should be evaluated no sooner than 2 weeks after electrode implantation. (Am J Vet Res2004;65:797–805)
Pharmacokinetics of lamivudine in cats
Authors: Zhang Weijiang , Mauldin Jeffrey K. , Schmiedt Chad W. , Brockus Charles W. , Boudinot F. Douglas , Stevenson M. A. McCrackin
Published: January 2006

Objective—To characterize the pharmacokinetics of lamivudine (3TC) in cats.

Animals—6 sexually intact 9-month-old barrier-reared domestic shorthair cats.

Procedure—Cats were randomly alloted into 3 groups, and lamivudine (25 mg/kg) was administered IV, intragastrically (IG), and PO in a 3-way crossover study design with 2-week washout periods between experiments. Plasma samples were collected for 12 hours after drug administration, and lamivudine concentrations were determined by high-performance liquid chromatography. Maximum plasma concentrations (Cmax), time to reach Cmax(Tmax), and bioavailability were compared between IG and PO routes. Area under the curve (AUC) and terminal phase halflife (t½) among the 3 administration routes were also compared.

Results—Plasma concentrations of lamivudine declined rapidly with a t½of 1.9 ± 0.21 hours, 2.6 ± 0.66 hours, and 2.7 ± 1.50 hours after IV, IG, and PO administration, respectively. Total body clearance and steady-state volume of distribution were 0.22 ± 0.09 L/h/kg and 0.60 ± 0.22 L/kg, respectively. Mean Tmaxfor IG administration (0.5 hours) was significantly shorter than Tmaxfor PO administration (1.1 hours). The AUC after IV, IG, and PO administration was 130 ± 55.2 mg·h/L, 115 ± 97.5 mg·h/L, and 106 ± 94.9 mg·h/L, respectively. Lamivudine was well absorbed after IG and PO administration with bioavailability values of 88 ± 45% and 80 ± 52%, respectively.

Conclusions and Clinical Relevance—Cats had a shorter t½but slower total clearance of lamivudine, compared with humans. Plasma concentrations of lamivudine were maintained above the minimum effective concentration for inhibiting FIV replication by 50% (0.14µM [0.032 µg/mL] for wild-type FIV clinical isolate) for at least 12 hours after IV, IG, or PO administration. (Am J Vet Res2004;65:841–846)
Evaluation of cytotoxicity and antiviral activity of recombinant human interferon alfa-2a and recombinant human interferon alfa-B/D hybrid against bovine viral diarrhea virus, infectious bovine rhinotracheitis virus, and vesicular stomatitis virus in vitro
Authors: Peek Simon F. , Bonds Michael D. , Gangemi David G. , Thomas Chester B. , Schultz Ronald D.
Published: January 2006

Objective—To evaluate cytotoxicity and antiviral activity of recombinant human interferon alfa-2a and recombinant human interferon alfa-B/D hybrid against cytopathic and noncytopathic bovine viral diarrhea virus (BVDV), infectious bovine rhinotracheitis virus (IBRV), and vesicular stomatitis virus (VSV) in vitro.

Sample population—Primary bovine testicular cells and Mardin Darby bovine kidney cells.

Procedures—To evaluate cytotoxicity, cells were added to serial dilutions of each interferon. To evaluate antiviral activity of each interferon, interferons were serially diluted 1:10, and tissue culture cells were added; virus was then added at 3 time points. Prevention of viral infection by interferon was defined as failure to induce cytopathologic effect for VSV, IBRV, and cytopathic BVDV and failure to detect virus immunohistochemically for cytopathic and noncytopathic BVDV.

Results—No evidence of cytotoxicity in either cell line was detected after incubation with interferon alfa- 2a or interferon alfa-B/D. However, reduced growth rates of tissue culture cells were detected for each interferon when undiluted interferon was tested. Comparable and profound antiviral activities against cytopathic and noncytopathic BVDV were evident for each interferon. Interferon alfa-2a and interferon a-B/D had comparable antiviral activities against VSV. Neither interferon had antiviral activity against IBRV.

Conclusions and Clinical Relevance—The safety and marked in vitro antiviral activity against noncytopathic BVDV, cytopathic BVDV, and VSV suggest that interferons alfa-2a and alfa-B/D may be useful for treatment of natural disease after infection with these viruses. (Am J Vet Res2004;65:871–874)
Pathologic changes in grossly normal menisci in dogs with rupture of the cranial cruciate ligament
Authors: Jackson Joshua , Vasseur Philip B. , Griffey Stephen , Walls Charles M. , Kass Philip H.
Published: January 2006

Objective—To determine whether histopathologic changes are detectable in grossly normal medial menisci from dogs with rupture of the cranial cruciate ligament (CCL).

Design—Case series.

Sample Population—40 medial menisci from dogs with rupture of the CCL and 20 medial menisci from control dogs without stifle joint disease.

Procedure—Data evaluated included age, duration of clinical signs, and whether rupture of the CCL was complete or incomplete. Three groups (n = 20/group) were also compared on the basis of 5 histologic criteria; group-1 menisci appeared grossly normal and were obtained from dogs with naturally occurring rupture of the CCL, group-2 menisci were grossly abnormal and were also obtained from dogs with naturally occurring CCL ruptures, and group-3 menisci were collected at postmortem from dogs without stifle joint disease that were of similar age and weight as dogs in groups 1 and 2.

Results—Group-2 menisci were significantly different from group-1 and -3 menisci in all histologic criteria. Group-1 menisci were significantly different from control menisci in only 1 of the 5 histologic criteria (cartilage differentiation). Dogs that were ≥ 3 years old had significantly more surface cellularity than did dogs that were < 3 years old. A significant difference was not detected between groups 1 and 2 with regard to completeness of rupture.

Conclusions and Clinical Relevance—Histologic changes in meniscal cartilage correlate with gross appearance of the cartilage at time of surgery for rupture of the CCL. On the basis of minimal histologic changes, routine removal of grossly normal menisci does not appear to be warranted. (J Am Vet Med Assoc2001;218:1281–1284)
Mammary duct ectasia in dogs: 51 cases (1992–1999)
Authors: Miller Margaret A. , Kottler Stephanie J. , Cohn Leah A. , Johnson Gayle C. , Kreeger John M. , Pace Lanny W. , Ramos-Vara José A. , Turk James R. , Turnquist Susan E.
Published: January 2006

Objective—To evaluate the clinical and pathologic characteristics of mammary duct ectasia in dogs.

Design—Retrospective study.

Animals—51 dogs with mammary duct ectasia.

Procedure—Information regarding body condition, history, number and location of affected mammary glands, appearance of lesions, surgical treatment, nonsurgical treatment, and evidence of recurrence or development of mammary neoplasia was obtained from surveys sent to referring veterinarians. Results of information from examination of histologic sections and referring veterinarians were evaluated for all mammary duct ectasia biopsies performed between 1992 and 1999.

Results—Duct ectasia was the primary diagnosis in 51 of 1,825 (2.8%) mammary biopsy specimens and comprised 48% of nonneoplastic mammary diseases. Affected dogs were evenly distributed over a range of 1 to 13 years of age, with a mean age at the time of diagnosis of 6.1 ± 3.1 years. All dogs were female (31 sexually intact, 20 spayed); 10 of 26 had whelped. Duct ectasia was described as nodular (26 dogs), cystic (13), and multiglandular (11) and located in caudal (31) more often than cranial (14) or middle glands (10). Ectasia recurred in 3 dogs. One dog had a history of previously excised mammary adenocarcinoma; another subsequently developed mammary carcinoma.

Conclusions and Clinical Relevance—Duct ectasia affected mature, sexually intact and spayed female dogs over a wide age range. Certain breeds were affected more commonly than expected. Increased risk for mammary neoplasia was not evident. Duct ectasia should be considered as a cause for mammary enlargement, especially in young dogs or when its cystic nature is evident. Mastectomy is usually curative, and neoplasia should be ruled out in dogs with ectasia. (J Am Vet Med Assoc2001;218:1303–1307)
Association of herd productivity and bulk-tank somatic cell counts in US dairy herds in 1996
Authors: Ott Stephen L. , Novak P. Raven
Published: January 2006

Objective—To assess the association of bulk-tank somatic cell counts (BTSCC) and the value of herd productivity (milk produced, calves born, and net costs for cow replacements) in US dairy herds in 1996.

Design—Randomized stratified national survey of dairy producers.

Sample Population—Records from 1,219 dairy herds in the top 20 dairy states.

Procedure—Responses for 1,178 herds had complete information for economic analysis. Per-cow value of production was determined for each herd. Data for herds with high (≥ 400,000 cells/ml) and medium (200,000 to 399,999 cells/ml) BTSCC were compared with values for herds with low BTSCC (< 200,000 cells/ml), using a multivariable regression model.

Results—In 1996, milk was priced at $0.287/kg ($13/cwt). Herds with low BTSCC annually generated $103.90/cow more in herd productivity than herds with medium BTSCC and $292.39/cow more than herds with high BTSCC.

Conclusions and Clinical Relevance—Increased BTSCC (> 200,000 cells/ml) were associated with a reduced value of productivity per cow. Thus, dairy producers have a financial incentive to seek out and implement cost-effective management practices that will enable them to decrease their BTSCC to < 200,000 cells/ml and maximize herd productivity. (J Am Vet Med Assoc2001;218:1325–1330)
Use of carboplatin for treatment of dogs with malignant melanoma: 27 cases (1989–2000)
Authors: Rassnick Kenneth M. , Ruslander David M. , Cotter Susan M. , Al-Sarraf Renee , Bruyette David S. , Gamblin Rance M. , Meleo Karelle A. , Moore Antony S.
Published: January 2006

Objective—To evaluate response rate and duration of malignant melanomas in dogs treated with carboplatin.

Design—Retrospective study.

Animals—27 client-owned dogs with spontaneously occurring measurable malignant melanomas.

Procedure—Records of dogs with melanomas treated with carboplatin from October 1989 to June 2000 were reviewed. Carboplatin was administered IV at doses of 300 or 350 mg/m2of body surface area. Response to treatment and evidence of drug toxicity were determined.

Result—Response to treatment could be evaluated in 25 dogs. Of those, overall response rate was 28%. One dog had a complete response, 6 (24%) dogs had a partial response (> 50% reduction in tumor burden). Median duration of partial response was 165 days. Eighteen dogs had stable disease (n = 9; 36%) or progressive disease (9; 36%). Response to treatment was significantly associated with carboplatin dose on a milligram per kilogram basis (15.1 mg/kg [6.9 mg/lb] of body weight vs 12.6 mg/kg [5.7 mg/lb]). Evidence of gastrointestinal toxicosis could be assessed in 27 dogs. Mean body weight of 5 dogs that developed gastrointestinal toxicosis was significantly less than that of 22 dogs without gastrointestinal toxicosis (9.9 kg [21.8 lb] vs 19.3 kg [42.5 lb]).

Conclusions and Clinical Relevance—Carboplatin had activity against macroscopic spontaneously occurring malignant melanomas in dogs and should be considered as an adjunctive treatment for microscopic local or metastatic tumors. Gastrointestinal toxicosis was associated with body weight. Because small dogs are more likely to have adverse gastrointestinal effects, gastrointestinal protectants should be considered for these patients. (J Am Vet Med Assoc2001;218:1444–1448)
Comparison of results of thoracic radiography, cytologic evaluation of bronchoalveolar lavage fluid, and histologic evaluation of lung specimens in dogs with respiratory tract disease: 16 cases (1996–2000)
Authors: Norris Carol R. , Griffey Stephen M. , Samii Valerie F. , Christopher Mary M. , Mellema Matthew S.
Published: January 2006

Objective—To compare results of thoracic radiography, cytologic evaluation of bronchoalveolar lavage (BAL) fluid, and histologic evaluation of biopsy and necropsy specimens in dogs with respiratory tract disease and to determine whether histologic evaluation provides important diagnostic information not attainable by the other methods.

Design—Retrospective study.

Animals—16 dogs.

Procedure—BAL fluid was classified as normal, neutrophilic, eosinophilic, mononuclear, mixed, neoplastic, or nondiagnostic. Radiographic abnormalities were classified as interstitial, bronchial, bronchointerstitial, or alveolar. Histologic lesions were classified as inflammatory, fibrotic, or neoplastic, and the predominant site of histologic lesions was classified as the alveoli, interstitium, or airway.

Results—The predominant radiographic location of lesions correlated with the histologic location in 8 dogs. Of 11 dogs with histologic evidence of inflammatory disease, 8 had inflammatory BAL fluid. Of the 2 dogs with histologic evidence of neoplasia, 1 had BAL fluid suggestive of neoplasia, and the other had BAL fluid consistent with septic purulent inflammation. Two dogs without any histologic abnormalities had mononuclear or nondiagnostic BAL fluid. Two dogs with histologic evidence of fibrosis had mononuclear or mixed inflammatory BAL fluid.

Conclusions and Clinical Relevance—Results suggest that although thoracic radiography, cytologic evaluation of BAL fluid, and histologic evaluation of lung specimens are complementary, each method has limitations in regard to how well results reflect the underlying disease process in dogs with respiratory tract disease. Lung biopsy should be considered in cases where results of radiography and cytology are nondiagnostic. (J Am Vet Med Assoc2001;218: 1456–1461)
Effects of parenteral administration of doramectin or a combination of ivermectin and clorsulon on control of gastrointestinal nematode and liver fluke infections and on growth performance in cattle
Authors: Loyacano Alvin F. , Skogerboe Terry L. , Williams James C. , DeRosa Andy A. , Gurie Jeffery A. , Shostrom Valerie K.
Published: January 2006

Objective—To compare effects of an injectable doramectin preparation with those of an injectable ivermectin-clorsulon preparation on control of gastrointestinal nematodes and liver flukes and on growth performance in cattle.

Design—Randomized complete block design.

Animals—60 crossbred calves.

Procedures—Calves (20/treatment group) were treated with doramectin or ivermectin-clorsulon or were not treated. Fecal samples were collected for nematode andFasciola hepaticaegg counts on day 0 and for up to 140 days after treatment. Cattle were weighed before treatment and at 28-day intervals until day 140.

Results—From day 7 through day 49, nematode egg counts for calves treated with doramectin or with ivermectin- clorsulon were significantly lower than those for untreated control calves. As the study progressed beyond day 56, the percentages of cattle with fluke eggs in their feces increased, but differences in regard to these percentages were not detected among the 3 groups. Average daily gain for the doramectin-treated cattle (0.79 kg/d [1.74 lb/d]) was significantly greater than that for the cattle treated with ivermectin-clorsulon (0.71 kg/d [1.56 lb/d]); values for both groups were significantly greater than that for the control cattle (0.62 kg/d [1.37 lb/d]).

Conclusions and Clinical Relevance—Results suggest that doramectin had a greater impact on subclinical gastrointestinal tract parasitism in calves, as demonstrated by growth performance, than did ivermectin- clorsulon. In the Gulf Coast region of the United States, spring-born nursing beef calves may have minimal grazing exposure toF hepaticaduring the peak fluke transmission period; therefore, mature fluke burdens may be negligible at the beginning of the fall season. (J Am Vet Med Assoc2001;218: 1465–1468)
Predicting behavioral changes associated with age-related cognitive impairment in dogs
Authors: Bain Melissa J. , Hart Benjamin L. , Cliff Kelly D. , Ruehl William W.
Published: January 2006

Objective—To monitor the progression of age-related
behavioral changes in dogs during a period of 6 to 18
months and to determine whether signs of dysfunction
in any of 4 behavioral categories can be used to
predict further impairment.

Design—Age-stratified cohort study.

Animals—63 spayed female and 47 castrated male
dogs 11 to 14 years of age.

Procedure—Data were collected from randomly
selected dog owners who were interviewed by telephone
twice at a 12- to 18-month interval; data were
included if the dog had lived ≥ 6 months between interviews.
The interview focused on signs of impairment
in the following behavioral categories: orientation in the
home and yard, social interactions with human family
members, house training, and the sleep-wake cycle.
Dogs were determined to have impairment in 0 behavioral
categories (on the basis of ≤ 1 sign for each category),
impairment in 1 category (≥ 2 signs of dysfunction
in that category), or impairment in ≥ 2 categories.

Results—Between interviews, 22% (16/73) of dogs
that did not have impairment in a category at the time of
the first interview developed impairment in that category
by the time of the second interview. Forty-eight percent
(13/27) of dogs that had impairment in 1 category
at the time of the first interview developed impairment
in ≥ 2categories by the time of the second interview and
were significantly more likely to develop impairment in ≥
2 categories, compared with dogs that initially had
impairment in 0 categories. Dogs with 1 sign of dysfunction
in orientation were significantly more likely to
develop impairment in that category, compared with
dogs that had 0 signs of dysfunction in orientation.

Conclusions and Clinical Relevance—Age-related
behavioral changes in dogs are progressive. Clinicians
should consider trying to predict which dogs are most
likely to become progressively impaired during the
subsequent 6 to 18 months. (J Am Vet Med Assoc
2001;218:1792–1795)
Epidemiologic features of pet evacuation failure in a rapid-onset disaster
Authors: Heath Sebastian E. , Voeks Susan K. , Glickman Larry T.
Published: January 2006

Objective—To describe epidemiologic features of pet evacuation failure after a hazardous chemical spill in which residents had no warning and only a few hours notice to evacuate.

Design—Cross-sectional study.

Sample Population—Pet-owning households that evacuated from a hazardous chemical spill with (n = 119) or without (122) their pets.

Procedures—Evacuees were surveyed by mail.

Results—261 of 433 (60.3%) dogs and cats in 241 households were not evacuated. Of the 241 households, 119 (49.4%) evacuated with their pets, 98 (40.7%) evacuated without them but later attempted to rescue them, and 24 (10.0%) neither evacuated their pets nor attempted to rescue them. Pet evacuation failure was most common in households that thought the evacuated area was safe for pets. Risk of pet evacuation failure increased in households with many animals, low pet attachment and commitment scores, and low levels of preparedness. Cat evacuation failure was associated with not having cat carriers. Nearly 80% of households that evacuated with their pets found accommodation with friends and family.

Conclusions and Clinical Relevance—Pet evacuation failure was common and jeopardized pets' health and well-being. Logistical challenges to transporting pets were substantial contributors to pet evacuation failure, whereas not knowing where to house a pet was only a minor concern. Most pet owners seemed self-reliant and acted appropriately towards their pets. Such self-reliant behavior by pet owners should be encouraged prior to disasters as part of an evacuation plan for households. (J Am Vet Med Assoc2001; 218:1898–1904)
Comparison of in-hospital versus 24-hour ambulatory electrocardiography for detection of ventricular premature complexes in mature Boxers
Authors: Meurs Kathryn M. , Spier Alan W. , Wright Nicola A. , Hamlin Robert L.
Published: January 2006

Objective—To evaluate the use of in-hospital electrocardiography (ECG) for detection of ventricular premature complexes (VPC), compared with 24-hour ambulatory ECG.

Design—Original study.

Animals—188 Boxers > 9 months old; 31 had a history of syncope, and 157 were healthy (no history of syncope).

Procedure—In-hospital ECG was performed on all Boxers for at least 2 minutes. Within 7 days after the in-hospital ECG was completed, 24-hour ambulatory ECG was performed.

Results—The specificity of in-hospital ECG was 100% for the detection of at least 50 VPC in a 24-hour period in dogs with syncope and 93% in healthy dogs. In-hospital ECG had poor sensitivity, although sensitivity increased as the number of VPC per 24 hours increased.

Conclusions and Clinical Relevance—Use of in-hospital ECG is highly specific for detection of at least 50 VPC during a 24-hour period. However, in-hospital ECG is insensitive, and a lack of VPC does not suggest that the dog does not have a substantial number of VPC during that same period. The use of in-hospital ECG appears to be inadequate for screening purposes and therapeutic evaluations in mature Boxers with ventricular arrhythmic disease. (J Am Vet Med Assoc2001;218:222–224)
Clinical features of dilated cardiomyopathy in Great Danes and results of a pedigree analysis: 17 cases (1990–2000)
Authors: Meurs Kathryn M. , Miller Matthew W. , Wright Nicola A.
Published: January 2006

Objective—To determine clinical features of dilated cardiomyopathy (DCM) in Great Danes and to determine whether DCM is familial in this breed.

Design—Retrospective study.

Animals—17 Great Danes with DCM.

Procedure—Medical records of Great Danes in which DCM was diagnosed on the basis of results of echocardiography (fractional shortening < 25%, endsystolic volume index > 30 ml/m2of body surface area) were reviewed. Pedigrees were obtained for affected animals, as well as for other Great Danes in which DCM had been diagnosed.

Results—Dilated cardiomyopathy appeared to be familial and was characterized by ventricular dilatation, congestive heart failure (left-sided or biventricular), and atrial fibrillation. Pedigree analysis suggested that DCM was inherited as an X-linked recessive trait, but the mode of inheritance could not be definitively identified.

Conclusions and Clinical Relevance—Results suggest that DCM may be an X-linked recessive trait in Great Danes. Thus, dogs with DCM probably should not be used for breeding, and female offspring of affected dogs should be used cautiously. Male offspring of affected females are at an increased risk of developing DCM and should be evaluated periodically for early signs of disease. Results of pedigree analysis were preliminary and should be used only as a guide for counseling breeders, rather than as a basis for making breeding decisions. (J Am Vet Med Assoc2001;218:729–732)