bluuebunny/crossref_metadata_2025 huggingface dataset:
Polymerase chain reaction-restriction fragment length polymorphism analysis of the SzP gene of Streptococcus zooepidemicus isolated from the respiratory tract of horses
Authors: Anzai Toru , Timoney John F. , Kuwamoto Yasushi , Wada Ryuichi , Oikawa Msaaki , Higuchi Tohru
Published: January 2006

Objective—To develop polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis for molecular typing of strains ofStreptococcus zooepidemicusand to use the new typing method to analyze a collection of isolates from the respiratory tract of Thoroughbreds.

Sample Population—10 strains ofS zooepidemicus, 65 isolates from the respiratory tract of 9 yearlings following long distance transportation, and 89 isolates from tracheal aspirates of 20 foals with pneumonia.

Procedure—Phenotypic variations in theSzPprotein were detected by western immunoblot analysis. Using PCR-RFLP analysis, genotypes were obtained with primer sets from theSzPgene, followed by restriction endonuclease digestion of the amplicons.

Results—Unique genotypic patterns were obtained with a primer set designed from both ends of the structural gene and the restriction endonucleaseDdeI. Forty-five isolates from the lymphoid tissue within the pharyngeal recess (ie, pharyngeal tonsil) of yearlings included 10SzPgenotypes andSzPphenotypes. Isolates from the trachea of each yearling were of a single genotype that was also present among isolates from the pharyngeal tonsil of the same horses. Isolates from tracheal aspirates of foals belonged to 14 genotypes.

Conclusion and Clinical Relevance—Analysis of theSzPgene by use of PCR-RFLP was effective for molecular typing of strains ofS zooepidemicusin the study of respiratory tract disease in horses. Results of PCR-RFLP analysis indicate that a single strain ofS zooepidemicuscan migrate from the pharyngeal tonsil to the trachea at a high rate in horses undergoing long distance transportation. (Am J Vet Res2002;63:1298–1301)
Plasma pharmacokinetics and tissue fluid concentrations of meropenem after intravenous and subcutaneous administration in dogs
Authors: Bidgood Tara , Papich Mark G.
Published: January 2006

Objective—To estimate pharmacokinetic variables
and measure tissue fluid concentrations of meropenem
after IV and SC administration in dogs.

Animals—6 healthy adult dogs.

Procedure—Dogs were administered a single dose
of meropenem (20 mg/kg) IV and SC in a crossover
design. To characterize the distribution of meropenem
in dogs and to evaluate a unique tissue fluid collection
method, an in vivo ultrafiltration device was used to
collect interstitial fluid. Plasma, tissue fluid, and urine
samples were analyzed by use of high-performance
liquid chromatography. Protein binding was determined
by use of an ultrafiltration device.

Results—Plasma data were analyzed by compartmental
and noncompartmental pharmacokinetic
methods. Mean ± SD values for half-life, volume of
distribution, and clearance after IV administration for
plasma samples were 0.67 ± 0.07 hours, 0.372 ±
0.053 L/kg, and 6.53 ± 1.51 mL/min/kg, respectively,
and half-life for tissue fluid samples was 1.15 ± 0.57
hours. Half-life after SC administration was 0.98 ±
0.21 and 1.31 ± 0.54 hours for plasma and tissue fluid,
respectively. Protein binding was 11.87%, and
bioavailability after SC administration was 84%.

Conclusions and Clinical Relevance—Analysis of
our data revealed that tissue fluid and plasma
(unbound fraction) concentrations were similar.
Because of the kinetic similarity of meropenem in the
extravascular and vascular spaces, tissue fluid concentrations
can be predicted from plasma concentrations.
We concluded that a dosage of 8 mg/kg, SC,
every 12 hours would achieve adequate tissue fluid
and urine concentrations for susceptible bacteria with
a minimum inhibitory concentration of 0.12 µg/mL.
(Am J Vet Res 2002;63:1622–1628)
Cardiopulmonary effects of xylazine and acepromazine in pregnant cows in late gestation
Authors: Hodgson David S. , Dunlop Colin I. , Chapman Phillip L. , Smith John A.
Published: January 2006

Objective—To determine effects of sedation achieved by xylazine (XYL) or acepromazine (ACE) on cardiopulmonary function and uterine blood flow in cows in late gestation.

Animals—8 cows between 219 and 241 days of gestation.

Procedure—Doses of ACE (0.02 mg/kg) or XYL (0.04 mg/kg) were administered IV. Measurements were obtained to determine cardiopulmonary effects and oxygen delivery to the uterus.

Results—Heart rate was not significantly affected by administration of ACE, but it decreased markedly after administration of XYL. Uterine artery flow was decreased at all times by XYL and was always less than for ACE. Xylazine increased uterine vascular resistance through 30 minutes and caused reduced PaO2and increased PaCO2at all time periods. Acepromazine caused a 5% decrease in PaO2only at 5 minutes. Xylazine reduced oxygen delivery by 59% at 5 minutes and 32% at 45 minutes. In contrast, ACE caused a nonsignificant reduction of oxygen delivery by 16% at 15 minutes and a return to baseline values by 45 minutes

Conclusions and Clinical Relevance—Xylazine markedly reduces flow and availability of oxygenated blood to the uterus, which may critically impair delivery of oxygen to the fetus at a stressful and important time of development or delivery. Acepromazine was associated with slight reductions of much shorter duration. When XYL is used to sedate pregnant cows, it could impose physiologic distress on the fetus and potentially increase fetal morbidity and mortality. When sedation of the dam is desirable, ACE could be an alternative to XYL. (Am J Vet Res2002;63:1695–1699)
Epidemiologic investigation of seroprevalence of antibodies to Toxoplasma gondii in cats and rodents
Authors: DeFeo Monica L. , Dubey J. P. , Mather Thomas N. , Rhodes III Richard C.
Published: January 2006

Objective—To provide an epidemiologic investigation of the seroprevalence of antibodies toToxoplasma gondiiin populations of cats and wild rodents in Rhode Island and to address the possible epidemiologic role of wild rodents in the spread of toxoplasmosis.

Animals—200 cats and 756 small wild rodents.

Procedure—Serum samples were obtained from 84 cats in animal shelters and 116 cats in veterinary hospitals. Serum samples were also obtained from 756 small wild rodents from multiple sites in Rhode Island. Sera from rodents and cats were assayed for antibodies toT gondiiby use of the modified agglutination test

Results—Overall, 42% (84/200) of cats had serum antibodies toT gondii. Seroprevalence was not significantly different between stray (50%; 42 /84) versus client-owned (36%; 42/116) cats, between male (43%; 40/94) versus female (42%; 39/93) cats, or between indoor (26%; 7/27) versus outdoor (39%; 35/89) cats. Seroprevalence rate of trapped rodents was 0.8% (6/756). Six rodents captured in Washington County accounted for of the seropositive rodents. Four of 6 of the seropositive rodents were trapped at a single site in Washington County (an abandoned barn). Five stray cats, known to have resided at the same site in Washington County as 4 of the seropositive rodents, were also found to be seropositive for antibodies toT gondii.

Conclusions and Clinical Relevance—Seroprevalence rate in rodents was not correlated with the seroprevalence rate in cats. Stray cats, especially those known to be feral, may be more likely to perpetuate the cat-mouse cycle ofT gondiithan clientowned cats. (Am J Vet Res2002;63:1714–1717)
Myoplasmic calcium regulation in myotubes from horses with recurrent exertional rhabdomyolysis
Authors: Lentz Linnea R. , Valberg Stephanie J. , Herold Lee V. , Onan Gary W. , Mickelson James R. , Gallant Esther M.
Published: January 2006

Objective—To determine whether alterations in myoplasmic calcium regulation can be identified in muscle cell cultures (myotubes) and intact muscle fiber bundles derived from Thoroughbreds affected with recurrent exertional rhabdomyolysis (RER).

Animals—6 related Thoroughbreds with RER and 8 clinically normal (control) Thoroughbred or crossbred horses.

Procedures—Myotube cell cultures were grown from satellite cells obtained from muscle biopsy specimens of RER-affected and control horses. Fura-2 fluorescence was used to measure resting myoplasmic calcium concentration as well as caffeine- and 4-chloro-m-cresol (4-CMC)-induced increases in myoplasmic calcium. In addition, intact intercostal muscle fiber bundles were prepared from both types of horses, and their sensitivities to caffeine- and 4-CMC-induced contractures were determined.

Results—Myotubes of RER-affected and control horses had identical resting myoplasmic calcium concentrations. Myotubes from RER-affected horses had significantly higher myoplasmic calcium concentrations than myotubes from control horses following the addition of ≥ 2mM caffeine; however, there was no difference in their response to 4-CMC (≥ 1mM). Caffeine contracture thresholds for RER and control intact muscle cell bundles (2 vs 10mM, respectively) were significantly different, but 4-CMC contracture thresholds of muscle bundles from RER-affected and control horses (500µM) did not differ.

Conclusions and Clinical Relevance—An increase in caffeine sensitivity of muscle cells derived from a family of related RER-affected horses was detected in vitro by use of cell culture with calcium imaging and by use of fiber bundle contractility techniques. An alteration in muscle cell calcium regulation is a primary factor in the cause of this heritable myopathy. (Am J Vet Res2002;63:1724–1731)
Establishment of an immortalized cell line and transplantable xenograft from a bronchioloalveolar lung carcinoma of a cat
Authors: Grossman Deborah A. , McNiel Elizabeth A. , Hackett Timothy B. , Barsky Sanford H.
Published: January 2006

Objective—To establish an immortalized cell line and
transplantable xenograft of feline bronchioloalveolar
lung carcinoma (BAC).

Sample Population—Pleural effusion from a 12-yearold
Persian male cat with BAC.

Procedure—Tumor cells from the pleural effusion
were grown in monolayer cell culture and injected
into severe combined immunodeficient (SCID) mice
to establish an immortalized cell line as well as a
transplantable xenograft.

Results—Both the primary lung carcinoma, the
derived cell line, and the transplantable xenograft had
evidence of a type-II pneumocyte origin expressing
lamellar bodies ultrastructurally and thyroid transcription
factor-1 and surfactant immunocytochemically. All
3 also expressed nuclear p53 immunoreactivity. A
metaphase spread of the cell line (SPARKY) probed
with fluorescein-labeled genomic feline DNA gave evidence
of its feline origin. Flow cytometric studies indicated
aneuploidy with a DNA index of 1.6. An R-banded
karyotype revealed a modal number of 66 including
the feline Y chromosome. The cell line had a doubling
time of 16 hours. The xenograft (SPARKY-X)
reached a diameter of 1 cm in 3 weeks in SCID mice.
Deoxyribonucleic acid fingerprint analysis revealed
that SPARKY and SPARKY-X were novel and strongly
matched each other, except for the murine component
found in SPARKY-X. Interestingly, SPARKY-X
manifested the characteristic lepidic growth pattern of
pulmonic BAC.

Conclusions—Both the cell line and xenograft
retained their autochthonous BAC phenotype, making
them useful for the subsequent dissection of molecular
abnormalities in feline BAC and in vitro screening
of chemotherapeutic agents. (Am J Vet Res 2002;
63:1745–1753)
Multivariate regression analysis of epidural pressure in cattle
Authors: Lee Inhyung , Yamagishi Norio , Oboshi Kenji , Yamada Haruo , Ohtani Masayuki
Published: January 2006

Objective—To evaluate the effects of growth, maturity,
and pregnancy on epidural pressure in cattle.

Animals—50 healthy Holstein cattle (18 heifers, 23
lactating cows, and 9 pregnant nonlactating cows).

Procedure—Each of the cattle was restrained in a
standing position. Height of the second lumbar vertebra's
transverse process (2LTP) and humeral tuberosity
(HT) on the right side as well as abdominal girth
(AG) were measured in each animal, and body condition
score (BCS) was ascertained. Skin caudal to the
first lumbar spinous process was aseptically prepared,
and anesthetic was injected. After inserting a
16-gauge 120-mm Tuohy needle in the ligamentum
flavum, a calibrated pressure transducer was connected
to the needle. Then, the needle was introduced
into the epidural space, and epidural pressure
was recorded.

Results—Mean ± SD residual epidural pressure of
heifers (–9.3 ± 3.3 mm Hg) was significantly higher than
that of lactating (–17.4 ± 5.5 mm Hg) or nonlactating
(–14.5 ± 2.4 mm Hg) cows. Stepwise regression of 5
variables revealed that only the difference in height
between 2LTP and HT (2LTP – HT) in heifers and only
BCS in lactating cows were significantly correlated with
residual epidural pressure. For all cattle, the optimal
equation (R2 = 0.47) describing the relationship was
y = –12.7 + 6.3x1 – 0.4x2 – 0.1x3, where y is epidural
pressure, x1 is BCS, x2 is 2LTP – HT, and x3 is age.

Conclusions and Clinical Relevance—Negative
epidural pressure was detected in standing cattle.
Growth, maturity, and pregnancy affect epidural pressure
in cattle. (Am J Vet Res 2002;63:954–957)
Validation of a cell culture bioassay for detection of petroleum exposure in mink (Mustela vison) as a model for detection in sea otters (Enhydra lutris)
Authors: Ziccardi Michael H. , Mazet Jonna A. K. , Gardner Ian A. , Boyce Walter M. , Denison Michael S.
Published: January 2006

Objective—To validate a luciferase bioassay, which is
based on a recombinant mouse hepatoma cell line, for
the detection of exposure to petroleum in mustelid
species.

Animals—122 American mink (Mustela vison) and 15
sea otters (Enhydra lutris).

Procedures—Mink were exposed to Bunker C fuel oil or
Alaska North Slope crude oil externally as a single exposure
or internally via low dose concentrations in their
ration for 6 months. Serum samples were analyzed for
cytochrome P450 1A1 induction by quantification of
luciferase activity in the bioassay. Mink liver specimens
were also evaluated for cytochrome P450 1A1 induction
by quantification of ethoxyresorufin-o-deethylase activity.
Serum collected from exposed and unexposed sea
otters was also analyzed using the luciferase bioassay.

Results—Serum samples from mink externally
exposed to petroleum had significantly increased
luciferase activities at 1 week after exposure. Serum
samples taken at later time points or from mink
exposed to either product in the ration did not cause
significant luciferase induction. Samples from otters
exposed to petroleum had significantly higher
luciferase induction as compared with samples from
otters not exposed to petroleum at 2 and 8 years after
the spill. Cytochrome P450 1A1 activity in liver specimens
collected from mink that were internally
exposed through diet was significantly increased at
the conclusion of our study.

Conclusion and Clinical Relevance—The luciferase
bioassay is a sensitive and specific method for determining
recent exposure to petroleum in mink. The
lack of luciferase activity in serum samples collected
from mink greater than 1 week after experimental
exposure was likely attributable to lower overall petroleum
exposure in our trial, compared with natural
exposures. (Am J Vet Res 2002;63:963–968)
Evaluation of the influence of prostaglandin E2 on recombinant equine interleukin-1β-stimulated matrix metalloproteinases 1, 3, and 13 and tissue inhibitor of matrix metalloproteinase 1 expression in equine chondrocyte cultures
Authors: Tung Jayne T. , Arnold Carolyn E. , Alexander Lee H. , Yuzbasiyan-Gurkan Vilma , Venta Patrick J. , Richardson Dean W. , Caron John P.
Published: January 2006

Objective—To determine the effects of prostaglandin E2(PGE2) on recombinant equine interleukin (IL)-1β-stimulated expression of matrix metalloproteinases (MMP 1, MMP 3, MMP 13) and tissue inhibitor of matrix metalloproteinase 1 (TIMP 1) in vitro.

Sample Population—Cultured equine chondrocytes.

Procedure—Stationary monolayers of first-passage chondrocytes were exposed to graduated concentrations of PGE2with or without a subsaturating dose (50 pg/ml) of recombinant equine IL-1β (reIL-1β) to induce expression of MMP 1, MMP 3, MMP 13, and TIMP 1, followed by RNA isolation and northern blotting. In subsequent experiments, gene expression was similarly quantified from mRNA isolated from cultures pretreated with phenylbutazone to quench endogenous PGE2synthesis, followed by exposure to reIL-1β and exogenous PGE2(5 mg/ml) with appropriate controls.

Results—Exogenous PGE2(10 mg/ml) significantly reduced reIL-1β-induced expression of MMP 1, MMP 3, MMP 13, and TIMP 1. Abrogation of cytokine induction with this dose of PGE2was comparable to that for dexamethasone (10–5M) control. Similarly, pretreatment with phenylbutazone, followed by exposure to reIL-1β and PGE2(5 mg/ml), was associated with a reduced expression of the genes of interest, an effect that was significant for MMP 1, MMP 13, and TIMP 1.

Conclusions and Clinical Relevance—The MMP and TIMP 1 are important mediators in the pathophysiologic events in osteoarthritis. The potential for physiologically relevant regulation of expression of these genes by PGE2is a consideration in the use of drugs that inhibit prostanoid synthesis in the treatment of equine arthropathies. (Am J Vet Res2002;63:987–993)
Evaluation of lysozyme and lactoferrin in lacrimal and other ocular glands of bison and cattle and in tears of bison
Authors: Pinard Chantale L. , Weiss Mark L. , Brightman Alan H. , Fenwick Bradley W. , Davidson Harriet J.
Published: January 2006

Objective—To evaluate lactoferrin and lysozyme content in various ocular glands of bison and cattle and in tears of bison.

Sample Population—Tissues of ocular glands obtained from 15 bison and 15 cattle and tears collected from 38 bison.

Procedure—Immunohistochemical analysis was used to detect lysozyme and lactoferrin in formalin-fixed, paraffin-embedded sections of the ocular glands. Protein gel electrophoresis was used to analyze ocular glands and pooled bison tears by use of a tris-glycine gel and SDS-PAGE. Western blotting was used to detect lactoferrin and lysozyme.

Results—Immunohistochemical staining for lactoferrin was evident in the lacrimal gland and gland of the third eyelid in cattle and bison and the deep gland of the third eyelid (Harder's gland) in cattle. Equivocal staining for lactoferrin was seen for the Harder's gland in bison. An 80-kd band (lactoferrin) was detected via electrophoresis and western blots in the lacrimal gland and gland of the third eyelid in cattle and bison, Harder's glands of cattle, and bison tears. An inconsistent band was seen in Harder's glands of bison. Lysozyme was not detected in the lacrimal gland of cattle or bison with the use of immunohistochemical analysis or western blots. Western blots of bison tears did not reveal lysozyme.

Conclusion and Clinical Relevance—Distribution of lactoferrin and a lack of lysozyme are similar in the lacrimal gland of cattle and bison. Differences in other tear components may be responsible for variability in the susceptibility to infectious corneal diseases that exists between bison and cattle. (Am J Vet Res2003;64:104–108)
Radiographic findings before and after oral administration of a magnet in cows with traumatic reticuloperitonitis
Authors: Braun Ueli , Gansohr Barbara , Flückiger Mark
Published: January 2006

Objective—To evaluate by use of radiography the efficacy
of oral administration of magnets in the treatment
of traumatic reticuloperitonitis in cows.

Animals—90 cows referred because of indigestion.

Procedure—Radiography of the reticulum was performed.
In all cows, radiographic findings revealed a
metal foreign body in the reticulum. A magnet was
administered orally, and the reticulum was again radiographed
to assess the position of the magnet and to
determine whether the foreign body was attached to
the magnet.

Results—The magnet was observed in the reticulum
in 75 cows and in the cranial aspect of the dorsal sac
of the rumen in 9 cows; in 6 cows, the magnet was
not observed. The foreign body was fully attached to
the magnet in 49 cows. In 6 cows, the foreign body
was in contact with the magnet but still penetrated
the reticulum. In 24 cows, the foreign body did not
contact the magnet, and in 11 cows, it was not clear
whether the foreign body was attached to the magnet.
A foreign body at an angle to the ventral aspect
of the reticulum of > 30° was less likely to become
attached to a magnet, compared with a foreign body
situated horizontally on the ventral aspect of the reticulum.
A foreign body with no contact to the ventral
aspect of the reticulum or a perforating foreign body
was also less likely to become attached to a magnet.

Conclusion and Clinical Relevance—Position of
the foreign body within the reticulum greatly influences
the efficacy of treatment with a magnet.
(Am J Vet Res 2003;64:115–120)
Anti-inflammatory effects of intramammary infusions of glycyrrhizin in lactating cows with mastitis caused by coagulase-negative staphylococci
Authors: Kai Kenzo , Komine Ken-ichi , Asai Ken-ichi , Kuroishi Toshinobu , Komine Yumiko , Kozutsumi Tomoyuki , Itagaki Masashi , Ohta Minoru , Endo Yasuo , Kumagai Katsuo
Published: January 2006

Objective—To determine the anti-inflammatory
effects of glycyrrhizin (GL) in lactating cows with mastitis
attributable to naturally occurring infection with
coagulase-negative staphylococci (CNS).

Animals—12 lactating Holstein cows with mastitis
attributable to infection with CNS and 2 healthy cows
without mastitis.

Procedure—Clinical signs, number of bacteria in milk,
somatic cell count (SCC) in milk, concentrations of
α-lactalbumin and lactoferrin in milk, and concentration
of histamine in milk were investigated before and
after intramammary infusion of GL (6 cows) or antimicrobials
(6 cows). Glands of 2 healthy cows were
infused with staphylococcal enterotoxin; milk leukocytes
were then harvested and incubated with various
doses of GL.

Results—In cows infected with CNS that had a low
bacterial concentration in milk, infusion of GL alone
resulted in significant improvements in swelling, firmness
of glands, and number of clots in milk, and it
decreased the SCC, but not significantly. Percentage
of neutrophils decreased significantly (to < 30%) by 2
days after infusion. Use of lactoferrin as a marker of
inflammation in mammary glands revealed a
decrease in concentrations, whereas use of α-lactalbumin
as a marker of recovery for mammary glands
revealed significant increases in concentrations in the
GL-infused group. Accompanying these anti-inflammatory
effects, a decrease in the concentration of histamine
in milk was observed in the GL-infused group.
Glycyrrhizin decreased histamine production by milk
leukocytes in a concentration-dependent manner.

Conclusions and Clinical Relevance—Infusion of
GL may regulate intramammary inflammation through
modulation of inflammatory mediators such as histamine.
(Am J Vet Res 2003;64:1213–1220)
Evaluation of the safety of ivermectin-praziquantel administered orally to pregnant mares
Authors: Mercier Patrick , Alves-Branco Francisco , Sapper Maria de Fatima , White Christopher Roger
Published: January 2006

Objective—To evaluate the safety of an orally administered
ivermectin and praziquantel paste with regard
to variables associated with clinical findings, parturition,
lactation, maternal care, and neonate viability in
pregnant mares.

Animals—40 pregnant mares.

Procedure—Mares were randomly allocated into
treatment (n = 20) and control (20) groups and administered
a placebo or 3 times the therapeutic dosage of
ivermectin (0.6 mg/kg) and praziquantel (4.5 mg/kg) at
14-day intervals until parturition. Physical examinations
were performed on mares and their foals after
parturition (on postpartum days 30, 60, and 90) to
identify any drug-related effects. As an aid in assessing
general health, hematologic and serum biochemical
analyses were performed monthly on the mares.

Results—In blood constituents, minor alterations that
were not biologically important were observed.
Reproductive performance was not affected by the
unusual treatment duration or high dosage, although
the drugs were administered during a crucial period of
equine embryonic development (30 to 60 days).
Neither adverse effects on mares nor abortions
occurred. Follow-up evaluations of the foals for a 3-
month period did not detect any abnormalities.

Conclusions and Clinical Relevance—Administration
of the ivermectin-praziquantel paste appears
to be safe in pregnant mares and their foals.
(Am J Vet Res 2003;64:1221–1224)
Gelatinase activity in synovial fluid and synovium obtained from healthy and osteoarthritic joints of dogs
Authors: Volk Susan W. , Kapatkin Amy S. , Haskins Mark E. , Walton Raquel M. , D'Angelo Marina
Published: January 2006

Objective—To determine matrix metalloproteinase
(MMP) activity in synovial fluid (SF) obtained from the
joints of dogs with degenerative joint disease (DJD)
secondary to various underlying conditions.

Sample Population—35 samples of SF obtained
from 18 clinically normal (control) dogs and 34 samples
of SF obtained from 17 dogs with DJD; dogs
with DJD were from 2 populations (client-owned
dogs and research dogs that had DJD secondary to
the lysosomal storage disease mucopolysaccharidosis
VII).

Procedure—MMP activity in samples of SF was
semiquantitatively examined by use of gelatin or
casein zymography. Western blot analysis was performed
by use of antibodies for MMP-2 and MMP-9.
In addition, in situ MMP activity was observed in sections
of synovial membrane obtained from healthy
and osteoarthritic joints.

Results—Samples of SF from osteoarthritic joints
had higher MMP-2 activity and dramatically increased
MMP-9 activity, compared with values for healthy
joints. Substrate-overlay analyses indicated minimal
gelatin-degrading activity in synoviocytes obtained
from control dogs, whereas greater activity was seen
in osteoarthritic synoviocytes, with additional activity
in the underlying tissue.

Conclusions and Clinical Relevance—Higher
MMP-2 activity and dramatic increases in MMP-9
activity were associated with the osteoarthritic
state, even though MMP-2 activity was detected
in healthy joints. This study expands information
on MMP production in SF of osteoarthritic joints in
other species and documents the similarity of
MMP activity patterns regardless of the cause of
DJD. (Am J Vet Res 2003;64:1225–1233)
Development and validation of a radioimmunoassay for the measurement of canine pancreatic lipase immunoreactivity in serum of dogs
Authors: Steiner Jörg M. , Williams David A.
Published: January 2006

Objective—To develop and validate a radioimmunoassay
(RIA) for measuring canine pancreatic
lipase immunoreactivity (cPLI) in serum obtained
from dogs.

Sample Population—Serum samples from 47
healthy dogs.

Procedures—Canine pancreatic lipase (cPL) was purified
from pancreatic specimens of dogs. Antibodies
against cPL were raised in rabbits and purified by use
of affinity chromatography. A tracer was produced by
iodination of cPL with 125I. An RIA was established and
validated by determination of sensitivity, working
range, dilutional parallelism, spiking recovery, and
intra- and interassay variability. A reference range for
cPLI in serum was established by use of the central
95th percentile for samples obtained from 47 healthy
dogs.

Results—Sensitivity and upper limit of the working
range were 0.88 and 863 µg/L, respectively.
Observed-to-expected ratios for serial dilutions
ranged from 84.9 to 116.5% for 4 samples. Observedto-
expected ratios for spiking recovery ranged from
82.8 to 128.6% for 4 samples. Coefficients of variation
for intra-assay variability for 4 serum samples
were 18.3, 4.2, 3.5, and 8.9%, whereas interassay
coefficients of variation were 29.2, 6.2, 3.9, and
4.4%, respectively. The reference range was 4.4 to
276.1 µg/L.

Conclusions and Clinical Relevance—We conclude
that the RIA described is sensitive, linear, accurate,
precise, and reproducible, with limited accuracy in the
high end of the working range and limited precision
and reproducibility in the low end of the working
range. Additional studies are needed to evaluate
whether this degree of accuracy, precision, and reproducibility
will negatively impact clinical use of this
assay. (Am J Vet Res 2003;64:1237–1241)
Effects of carnitine and taurine on fatty acid metabolism and lipid accumulation in the liver of cats during weight gain and weight loss
Authors: Ibrahim Wissam H. , Bailey Nathanael , Sunvold Gregory D. , Bruckner Geza G.
Published: January 2006

Objective—To determine the effects of carnitine (Ca) or taurine (Ta) supplementation on prevention of lipid accumulation in the liver of cats.

Animals—24 adult cats.

Procedure—Cats were fed a weight-gaining diet sufficient in n-6 polyunsaturated fatty acids (PUFAs), low in long-chain n-3 PUFAs (n-3 LPUFA), and containing corn gluten for 20 weeks. Cats gained at least 30% in body weight and were assigned to 4 weight-reduction diets (6 cats/diet) for 7 to 10 weeks (control diet, control plus Ca, control plus Ta, and control plus Ca and Ta).

Results—Hepatic lipids accumulated significantly during weight gain and weight loss but were not altered by Ca or Ta after weight loss. Carnitine significantly increased n-3 and n-6 LPUFAs in hepatic triglycerides, decreased incorporation of 13C palmitate into very-low-density lipoprotein and hepatic triglycerides, and increased plasma ketone bodies. Carnitine also significantly increased weight loss but without altering the fat to lean body mass ratio. Taurine did not significantly affect any variables. Diets low in n-3 LPUFAs predisposed cats to hepatic lipidosis during weight gain, which was further exacerbated during weight loss. Mitochondrial numbers decreased during weight gain and weight loss but were not affected by treatment. Carnitine improved fatty acid oxidation and glucose utilization during weight loss without correcting hepatic lipidosis.

Conclusions and Clinical Relevance—The primary mechanism leading to hepatic lipidosis in cats appears to be decreased fatty acid oxidation. Carnitine may improve fatty acid oxidation but will not ameliorate hepatic lipidosis in cats fed a diet low in n-3 fatty acids. (Am J Vet Res2003;64:1265–1277)
Quantitation of house dust mites and house dust mite allergens in the microenvironment of dogs
Authors: Randall Amy , Hillier Andrew , Cole Lynette K. , Kwochka Kenneth W. , Needham Glen , Wassom Donald L.
Published: January 2006

Objective—To quantitate the density ofDermatophagoides farinaeandD pteronyssinusand concentrations of house dust mite (HDM) allergens (Der f 1, Der p 1, and Group 2 allergens) in the indoor microenvironment of dogs.

Sample Population—50 homes in Columbus, Ohio.

Procedures—In each home, samples of dust were collected from 3 locations in which dogs spent most time. Whenever possible, the species of mites collected was identified. Mite density (mites/g of dust) was assessed, and allergen concentrations were assayed by standardized ELISAs. Relative humidity and temperature in each home were monitored during a 5-day period. Characteristics of homes and sample sources were evaluated.

Results—Dust samples from all 50 homes contained ≥ 1 HDM allergen; Der f 1 and Der p 1 were detected in 100 and 74% of homes, respectively. Fifteen homes had HDMs; compared withD pteronyssinus, D farinaewas found more commonly (14/15 homes) and at a higher density. Basements, homes without central airconditioning, and dog beds that were ≥ 1 year old had high HDM allergen concentrations. Homes with ≥ 2 µg of Der f 1 or Group 2 allergens/g of dust or ≥ 100 mites/g of dust were significantly more likely to have a maximum relative humidity ≥ 75%.

Conclusions and Clinical Relevance—Results indicate the presence of HDMs and HDM allergens in the specific microenvironment of dogs in homes. Factors associated with high levels of exposure were identified, which may be associated with increased risk for sensitization and development of atopic diseases. (Am J Vet Res2003;64:1301–1309)
Comparison of electroacupuncture and butorphanol on respiratory and cardiovascular effects and rectal pain threshold after controlled rectal distention in mares
Authors: Skarda Roman T. , Muir III William W.
Published: January 2006

Objective—To compare effects of electroacupuncture
and butorphanol on hemodynamic and respiratory
variables and rectal analgesia in mares after controlled
rectal distention.

Animals—8 healthy mares.

Procedure—Each horse received saline (0.9% NaCl)
solution (0.01 mL/kg, IV; control treatment), butorphanol
tartrate (0.1 mg/kg, IV), or 2 hours of electroacupuncture
(EA) at acupoints Bladder 21, 25, and
27 on both sides of the vertebral column, Bai hui, and
Stomach 36 (right side only). Order of treatments in
each mare was randomized. At least 7 days elapsed
between treatments. A balloon was inserted in the
rectum of each mare, and controlled distention of the
balloon (pressures of ≤ 220 mm Hg) was used to measure
nociceptive rectal pain threshold. Rectal temperature
and cardiovascular and respiratory variables
were measured before (baseline) and 5, 15, 30, 60, 90,
and 120 minutes after onset of each treatment.

Results—Butorphanol produced greater increases in
rectal pain threshold, compared with EA (mean ± SD,
214 ± 24 vs 174 ± 35 mm Hg of balloon pressure).
Electroacupuncture produced minimal cardiovascular
and respiratory changes. Although clinically not important,
butorphanol produced moderate significant
increases in heart and respiratory rates, arterial blood
pressure, and rectal temperature and decreases in
arterial oxygen tension. Arterial pH, carbon dioxide
tension, bicarbonate concentrations, base excess,
Hct, and concentration of total solids were not significantly
different from baseline values after EA, butorphanol,
and control treatments.

Conclusions and Clinical Relevance—Electroacupuncture
and butorphanol (0.1 mg/kg, IV) may provide
useful rectal analgesia in horses. (Am J Vet Res 2003;64:137–144)
Results of epidemic simulation modeling to evaluate strategies to control an outbreak of foot-and-mouth disease
Authors: Bates Thomas W. , Thurmond Mark C. , Carpenter Tim E.
Published: January 2006

Objective—To assess estimated effectiveness of
control and eradication procedures for foot-andmouth
disease (FMD) in a region of California.

Sample Population—2,238 herds and 5 sale yards in
Fresno, Kings, and Tulare counties of California.

Procedure—A spatial stochastic model was used to
simulate hypothetical epidemics of FMD for specified
control scenarios that included a baseline eradication
strategy mandated by USDA and supplemental control
strategies of slaughter or vaccination of all animals within
a specified distance of infected herds, slaughter of
only high-risk animals identified by use of a model simulation,
and expansion of infected and surveillance zones.

Results—Median number of herds affected varied
from 1 to 385 (17% of all herds), depending on type
of index herd and delay in diagnosis of FMD.
Percentage of herds infected decreased from that of
the baseline eradication strategy by expanding the
designated infected area from 10 to 20 km (48%),
vaccinating within a 50-km radius of an infected herd
(41%), slaughtering the 10 highest-risk herds for each
infected herd (39%), and slaughtering all animals
within 5 km of an infected herd (24%).

Conclusions and Clinical Relevance—Results for the
model provided a means of assessing the relative merits
of potential strategies for control and eradication of
FMD should it enter the US livestock population. For the
study region, preemptive slaughter of highest-risk herds
and vaccination of all animals within a specified distance
of an infected herd consistently decreased size and
duration of an epidemic, compared with the baseline
eradication strategy. (Am J Vet Res 2003;64:205–210)
Effects of ventilation and isoflurane end-tidal concentration on intracranial and cerebral perfusion pressures in horses
Authors: Brosnan Robert J. , Steffey Eugene P. , LeCouteur Richard A. , Imai Ayako , Farver Thomas B. , Kortz Gregg D.
Published: January 2006

Objective—To measure the effects of isoflurane end-tidal concentration and mode of ventilation (spontaneous vs controlled) on intracranial pressure (ICP) and cerebral perfusion pressure (CPP) in horses.

Animals—6 adult horses of various breeds.

Procedure—Anesthesia was induced and maintained with isoflurane in O2in 6 healthy, unmedicated, adult horses. Using a subarachnoid strain gauge transducer, ICP was measured. Blood gas tensions and carotid artery pressures also were measured. Four isoflurane doses were studied, corresponding to the following multiples of the minimum alveolar concentration (MAC): 1.0 MAC, 1.2 MAC, 1.4 MAC, and 1.6 MAC. Data were collected during controlled ventilation and spontaneous ventilation at each dose.

Results—Increasing isoflurane end-tidal concentration induced significant dose-dependent decreases in mean arterial pressure (MAP) and CPP but no change in ICP. Hypercapnic spontaneous ventilation caused significant increases in MAP and ICP, compared with normocapnic controlled ventilation; no change in CPP was observed.

Conclusion and Clinical Relevance—Hypercapnia likely increases cerebral blood flow (CBF) by maintaining CPP in the face of presumed cerebral vasodilation in healthy anesthetized horses. The effect of isoflurane dose on CBF, however, remains unresolved because it depends on the opposinginfluences of a decrease in CCP and cerebral vasodilation. (Am J Vet Res2003;64:21–25)
Antagonism of adenosine receptors by caffeine and caffeine metabolites in equine forebrain tissues
Authors: Chou Chi-Chung , Vickroy Thomas W.
Published: January 2006

Objective—To determine the presence of adenosine receptor subtypes A1and A2ain equine forebrain tissues and to characterize the interactions of caffeine and its metabolites with adenosine receptors in the CNS of horses.

Sample Population—Brain tissue specimens obtained during necropsy from 5 adult male research

Procedures—Membrane-enriched homogenates from cerebral cortex and striatum were evaluated by radioligand binding assays with the A1-selective ligand [3H]DPCPX and the A2a-selective ligand [3H]ZM241385. Functional responses to adenosine receptor agonists and antagonists were determined by a nucleotide exchange assay using [35S]-guanosine 5'-(γ-thio) triphosphate ([35S]GTPγS).

Results—Saturable high affinity [3H]DPCPX binding (A1) sites were detected in cerebral cortex and striatum, whereas high-affinity [3H]ZM241385 binding (A2a) sites were detected only in striatum. Caffeine and related methylxanthines had similar binding affinities at A1 and A2a sites with rank orders of drug binding affinities (theophylline > paraxanthine ≥ caffeine >> theobromine) similar to other species. [35S]GTPγS exchange revealed that caffeine and its metabolites act as pure adenosine receptor antagonists at concentrations that correspond to A1and A2areceptor binding affinities.

Conclusions and Clinical Relevance—Results of our study affirm the presence of guanine nucleotide binding protein linked adenosine receptors (ie, high-affinity A1and A2aadenosine receptors) in equine forebrain tissues and reveal the antagonistic actions by caffeine and several biologically active caffeine metabolites. Antagonism of adenosine actions in the equine CNS by these stimulants may be responsible for some central actions of methylxanthine drugs, including motor stimulation and enhanced racing performance. (Am J Vet Res2003;64:216–224)
Endotoxn-induced nonthyroidal illness in dogs
Authors: Panciera David L. , Ritchey Jerry W. , Ward Daniel L.
Published: January 2006

Objective—To determine the effects of endotoxin administration on thyroid function test results and serum tumor necrosis factor-α (TNF-α) activity in healthy dogs.

Animals—6 healthy adult male dogs.

Procedures—Serum concentrations of thyroxine (T4), 3,5,3'-triiodothyronine (T3), 3,3'5'-triiodothyronine (rT3), free T4(fT4), and endogenous canine thyroid stimulating hormone (TSH), and TNF-α activity were measured before (day–1; baseline), during (days 0 to 3), and after (days 4 to 24) IV administration of endotoxin every 12 hours for 84 hours.

Results—Compared with baseline values, serum T3 concentration decreased significantly, whereas rT3concentration increased significantly 8 hours after initial endotoxin administration. Serum T4concentration decreased significantly at 8 and 12 hours after initiating endotoxin administration. Serum T4concentration returned to reference range limits, then decreased significantly on days 6 to 12 and 16 to 20. Serum fT4concentration increased significantly at 12, 24, and 48 hours after cessation of endotoxin treatment, compared with baseline values. Serum rT3concentration returned to reference range, then decreased significantly days 5 and 7 after stopping endotoxin treatment. Serum TNF-α activity was significantly increased only 4 hours after initial endotoxin treatment, compared with baseline activity.

Conclusions and Clinical Relevance—Endotoxin administration modeled alterations in thyroid function test results found in dogs with spontaneous nonthyroidal illness syndrome. A decrease in serum T4and T3concentrations and increase in serum rT3concentration indicate impaired secretion and metabolism of thyroid hormones. The persistent decrease in serum T4concentration indicates that caution should be used in interpreting serum T4concentrations after resolution of an illness in dogs. (Am J Vet Res2003;64:229–234)
Evaluation of serum obtained from atopic dogs with dermatitis attributable to Malassezia pachydermatis for passive transfer of immediate hypersensitivity to that organism
Authors: Morris Daniel O. , DeBoer Douglas J.
Published: January 2006

Objective—To determine the functionality of canine anti-MalasseziaIgE via the passive transfer of immediate hypersensitivity localized to the skin (ie, cutaneous anaphylaxis) from atopic dogs with dermatitis attributable to overgrowth ofMalassezia pachydermatis(Malasseziadermatitis [MD]) to healthy recipient dogs by use of the Prausnitz-Küstner (P-K) technique.

Animals—7 clinically normal dogs, 32 atopic dogs with MD, serum from 11 atopic dogs with MD, and 3 healthy dogs without prior sensitization toM pachydermatis.

Procedure—Serum from atopic dogs with MD was used for P-K tests in 3 clinically normal recipient dogs. Serial dilutions of untreated, heat-inactivated, IgE-absorbed, and bovine serum albumin (BSA)- absorbed (control) aliquots of serum were injected ID in triplicate for dermal sensitization. Twenty-four, 48, and 72 hours later, a crude extract ofM pachydermatiswas injected ID into the sites used for sensitization injections, and immediate hypersensitivity reactions were graded on a 4-point scale.

Results—Untreated serum caused P-K reactivity beginning 24 hours after passive sensitization and persisting through 72 hours (titers, 1:32 to 1:64). Heat inactivation and IgE-absorption of serum eliminated P-K reactivity, whereas treatment of serum with BSA did not.

Conclusions and Clinical Relevance—Analysis of P-K test results supports the passive transfer of cutaneous anaphylaxis by anti-MalasseziaIgE and indicates it is functional in type-1 hypersensitivity reactions of atopic dogs with MD. Reduction or blockade of anti-MalasseziaIgE in atopic dogs with MD may provide better clinical control of the disease. (Am J Vet Res2003;64:262–266)
Comparison of volumetric urine collection versus single-sample urine collection in horses consuming diets varying in cation-anion balance
Authors: McKenzie Erica C. , Valberg Stephanie J. , Godden Sandra M. , Pagan Joe D. , Carlson Gary P. , MacLeay Jennifer M. , DeLaCorte Flavio D.
Published: January 2006

Objective—To determine daily variation in urinary clearance and fractional excretion (FE) of electrolytes and minerals within and between horses and to compare volumetric and single-sample urine collection for determining FE values of diets with a range of dietary cation-anion balance (DCAB).

Animals—5 Thoroughbred and 6 mixed-breed mares.

Procedure—3 isocaloric diets with low, medium, and high DCAB values (85, 190, and 380 mEq/kg of dry matter, respectively) were each fed for 14 days. Daily blood samples, single urine samples collected by using a urinary catheter (5 mares), and volumetric urine collections (6 mares) were obtained during the last 72 hours of each diet.

Results—Urine and plasma pH values, plasma concentrations, and FE values of sodium, chloride, potassium, magnesium, phosphorus, and calcium were altered by varying the DCAB. Noticeable variation in clearance and FE values was detected within horses from day-to-day on the same diet as well as between horses. Fractional excretion values were not significantly different between single-sample and volumetric methods, except for magnesium in the high DCAB diet. Volumetric and single-sample collections revealed similar patterns of change in urinary FE values with varying DCAB, except for calcium and magnesium.

Conclusions and Clinical Relevance—Substantial variation in clearance and FE of electrolytes and minerals are evident within horses between 24-hour periods as well as between horses fed a specific diet. Three daily urine samples provide similar information regarding dietary-induced changes in clearance and FE values (excluding calcium and magnesium) as that obtained by volumetric urine collection. (Am J Vet Res2003;64:284–291)
Plasma concentrations of praziquantel after oral administration of single and multiple doses in loggerhead sea turtles ( Caretta caretta )
Authors: Jacobson Elliott R. , Harman Glenn R. , Maxwell Lara K. , Laille Eric J.
Published: January 2006

Objective—To determine the pharmacokinetics of
praziquantel following single and multiple oral dosing
in loggerhead sea turtles.

Animals—12 healthy juvenile loggerhead sea turtles.

Procedure—Praziquantel was administered orally as
a single dose (25 and 50 mg/kg) to 2 groups of turtles;
a multiple-dose study was then performed in which 6
turtles received 3 doses of praziquantel (25 mg/kg,
PO) at 3-hour intervals. Blood samples were collected
from all turtles before and at intervals after drug
administration for assessment of plasma praziquantel
concentrations. Pharmacokinetic analyses included
maximum observed plasma concentration (Cmax),
time to maximum concentration (Tmax), area under the
plasma praziquantel concentration-time curve, and
mean residence time (MRTt).

Results—Large interanimal variability in plasma praziquantel
concentrations was observed for all dosages.
One turtle that received 50 mg of praziquantel/kg
developed skin lesions within 48 hours of administration.
After administration of 25 or 50 mg of praziquantel/
kg, mean plasma concentrations were below
the limit of quantification after 24 hours. In the multiple-
dose group of turtles, mean plasma concentration
was 90 ng/mL at the last sampling time-point (48
hours after the first of 3 doses). In the single-dose
study, mean Cmax and Tmax with dose were not significantly
different between doses. After administration
of multiple doses of praziquantel, only MRTt was significantly
increased, compared with values after
administration of a single 25-mg dose.

Conclusions and Clinical Relevance—Oral administration
of 25 mg of praziquantel/kg 3 times at 3-hour
intervals may be appropriate for treatment of loggerhead
sea turtles with spirorchidiasis. (Am J Vet Res 2003;64:304–309)