bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of affinity of Pasteurella multocida isolates for porcine respiratory tract mucus, and partial characterization of the receptors
Authors: Letellier A. , Dubreuil D. , Roy G. , Fairbrother J. M. , Jacques M.
Published: January 2024

The ability of 25 Pasteurella multocida isolates to adhere in vitro to porcine respiratory tract mucus was examined. Microplate wells were coated with crude mucus preparation, then bacteria were added. After incubation, unbound bacteria were removed by washing, and the number of mucus-bound bacteria was estimated by quantitation of the adherent colony-forming units and by use of an elisa. Pasteurella multocida had affinity to respiratory tract mucus, although significant differences were not observed in affinity of capsular type-A and type-D isolates. Preliminary characterization, using ultrafiltration, gel filtration chromatography, electrophoresis, and enzymatic treatments, indicated that the receptors may be a class of protein molecules of low molecular weight (< 25,000). The origin of these receptors, however, is not known at this time.
Renal clearance and fractional excretion of electrolytes over four 6-hour periods in cattle
Authors: Fleming S. A. , Hunt E. L. , Riviere J. E. , Anderson K. L.
Published: January 2024

Four consecutive 6-hour urine sample collections were performed on 7 healthy adult Holstein cows fed a diet of coastal Bermuda hay with ad libitum water consumption. Urine (via indwelling urinary catheter) and venous blood samples were collected at 6, 12, 18, and 24 hours.

Total 24-hour urine production for the 7 cows ranged from 4,515 to 7,130 ml/d (mean ± sd, 5,633 ± 946 ml/d) or 0.02 to 0.04 ml/kg of body weight/d (mean ± sd, 0.03 ± 0.007 ml/kg/d). Renal clearance (C) of creatinine (Cr), sodium (Na), calcium (Ca), and magnesium (Mg) varied significantly (P < 0.05) among individuals, but did not vary significantly among the four 6-hour collection periods. Clearance of chloride (CI) and phosphorous (P) did not vary significantly either among individuals or among the four 6-hour periods. Clearance of potassium (K) varied significantly (P < 0.05) among individuals and among the four 6-hour periods.

Creatinine clearance was significantly (P < 0.01) correlated with CCI, CCa, CP, and CMg when all data were considered. Significant (P < 0.05) correlations were also found between CCI, and CK, CCa, CP, and CMg; between CCa and CP and CMg; and between CP and CMg.

Fractional excretion (fe) of Na, K, CI, Ca, P, and Mg did not vary significantly among the four 6-hour periods. Fractional excretion of Na, Ca, and Mg (P < 0.01) and K and P (P < 0.05) varied significantly within individuals among the 6-hour periods. Mean fe values, calculated by averaging values for each of the 4 collection periods for all 7 cows, ranged from 0.05 to 0.78% for fena; 129.33 to 670.40% for fek; 1.23 to 6.23% for feci; 0.17 to 4.44% for feca; 0.36 to 1.14 for fep; and 4.96 to 11.73% for femg.

Linear relationships between the clearance and fractional excretion of electrolytes were observed on base-10 logarithmically transformed data for Na, Ca, P, and Mg. Linear relationship was not found between CK and fek or between CCI and feci.
Development of surgical techniques for preparation of in vitro-isolated perfused porcine skin flaps for percutaneous absorption studies
Authors: Bowman K. F. , Monteiro-Riviere Nancy A. , Riviere J. E.
Published: January 2024

We developed a single-pedicle, axial pattern tubed skin flap that could be transferred to an in vitro perfusion apparatus. On the basis of results of prosections, angiography, contact radiography, and surviving-length studies, it was concluded that a single-pedicle, axial pattern skin flap measuring 4 cm × 12 cm incorporating the caudal superficial epigastric artery would survive to its entire length. Subsequently, a surgical (stage 1) procedure was developed for the routine preparation of single-pedicle, axial pattern tubed skin flaps. Healing after the stage-1 procedure was evaluated by visual inspection and fluorescein angiography. Stage-1 procedures were performed successfully 149 of 160 (93%) times. A second surgical (stage 2) procedure was developed for routine cannulation of the caudal superficial epigastric artery and harvest of the tubed skin flap. Stage-2 procedures were performed successfully 136 of 144 (94%) times.
Evaluation of sodium carboxymethylcellulose for prevention of experimentally induced abdominal adhesions in ponies
Authors: Moll H. David , Schumacher John , Wright James C. , Spano Joseph S.
Published: January 2024

Twelve ponies were used to evaluate the reliability of an abdominal adhesion model and the efficacy of intraperitoneal infusion of sodium carboxymethylcellulose in preventing abdominal adhesions. A celiotomy was performed on each of the 12 ponies and the serosa of the distal portion of the jejunum was abraded with a dry gauze sponge at 5 locations. In addition to the serosal damage, a single 2-0 chromic gut suture was placed through the seromuscular layer of the jejunum in the center of the abraded area. After closure of the celiotomy, a 1% solution of sodium carboxymethylcellulose (7 ml/kg of body weight) was infused into the peritoneal cavity of 6 ponies. The other ponies served as untreated controls. All ponies were euthanatized 14 days after surgery.

All ponies in the control group had abdominal adhesions at the time of necropsy. Four of the 6 ponies in the treatment group were free of adhesions. There was a significant (P < 0.0001) difference in the total number of adhesions between the 2 groups.
Characterization by restriction endonuclease analysis and seroagglutination of strains of Mycobacterium avium and Mycobacterium intracellular obtained from farmed deer
Authors: Wards Barry J. , de Lisle Geoffrey W. , Yates Gary F. , Dawson David J.
Published: January 2024

Restriction endonuclease analysis and seroagglutination were used to characterize strains of Mycobacterium avium and Mycobacterium intracellular (collectively, mai) recovered from 1 local herd and 2 imported shipments of red deer (Cervus elaphus) that developed sensitization to bovine tuberculin during skin testing. A total of 31 mai strains were isolated from lymph node pools (head, thorax, abdomen, and peripheral regions) of 21 of 29 local deer. Similarly, 15 mai strains were isolated from the lymph node pools of 12 deer from the 2 imported shipments. Mycobacterial strains were isolated from more than 1 of the lymph node pools of 9 local and 2 imported deer. Most of the strains (59% from local deer, 46% from imported deer) were recovered from the lymph nodes of the head region. After restriction endonuclease analysis of these isolates using the enzymes Bcl I, BstEII, and Pvu II, 26 of the strains from the local herd were separated into 3 groups, each consisting of strains with indistinguishable or closely related patterns. Seroagglutination results indicated that the first of these groups contained strains belonging to serotype 1, the second group contained strains belonging to serotype 8; and the third group of strains belonged to serotypes 3 and 9. The 5 remaining strains from the local herd had unrelated restriction patterns. One of these belonged to serotype 3, whereas the remaining 4 could not be serotyped. Restriction analysis of the 15 strains from the imported deer identified 2 groups. Seroagglutination results indicated that 1 group contained strains belonging to serotype 2 and the other group contained strains belonging to serotype 8. Some deer were infected with 2 or more strains that differed in serotype and/or restriction pattern. Results indicate that a single source of infection was not apparent for either herd and that a number of mai strains may possibly have contributed to tuberculin sensitization.
Quantitation of bovine immunoglobulins in culture fluids by use of sandwich radioimmunoassay with monoclonal antibodies
Authors: Srikumaran S. , Kluever E. A. , Onisk D. V. , Hariharan K.
Published: January 2024

Bovine immunoglobulin isotype-specific murine monoclonal antibodies were used in sandwich radioimmunoassays to detect and quantitate bovine IgG1, IgG2, IgM, and IgA in culture fluids. The concentrations of bovine immunoglobulins in unknown samples were extrapolated from standard curves generated with bovine monoclonal immunoglobulins. The lowest detection limits for the bovine immunoglobulin isotypes ranged from 65 to 270 ng/ml.
Electrophysiologic studies of the cutaneous innervation of the pelvic limb of male dogs
Authors: Haghighi S. S. , Kitchell R. L. , Johnson R. D. , Bailey C. S. , Spurgeon T. L.
Published: January 2024

The area of skin supplied by the afferent fibers in one cutaneous nerve is called the cutaneous area (ca) for that nerve. The ca of peripheral branches of lumbar and sacral spinal nerves responsive to the stimulation of hair follicle mechanoreceptors were mapped in 27 dogs.

The amount of overlap among the ca was similar to that found for other ca of the body. The ca of peripheral branches of the sciatic nerve were restricted to the lateral, cranial, and caudal aspects of the pelvic limb distal to the stifle. The ca of the saphenous nerve was located on the medial side of the limb, except for a small area located on the lateral side of the crus. The distal part of the ca of the saphenous nerve was completely overlapped in the hind paw by branches of the superficial peroneal nerve laterally and the medial plantar branch of the tibial nerve medially. The ca for the deep peroneal nerve was located on the dorsal surface of the webbing between digits 2 and 3 and the adjacent skin of these digits.

The ca of the plantar branches of the tibial nerve were small in comparison with the diameter of the nerve, suggesting that these branches contained nerve fibers supplying other, deeper structures in the hindpaw and that damage to these nerves would interfere with cutaneous sensation in only a small region on the plantar surface of the hindpaw.

Knowledge of the ca of the various branches of the sciatic nerve allows more accurate localization of injury to the sciatic nerve or its branches by using areas of anesthesia.
Decreased respiratory burst activity in neonatal bovine neutrophils stimulated by protein kinase C agonists
Authors: Doré Monique , Slauson David O. , Neilsen Nancy R.
Published: January 2024

Newborn calves have a high susceptibility to bacterial infections, which may be related to the impaired neutrophil defense functions in newborns. The oxygen-dependent production of the free radical superoxide anion (O2-) represents an important part of the leukocyte respiratory burst central to neutrophil-directed defenses against bacterial infection. Because protein kinase C (pkc) activation is considered to be an important step in the signal transduction pathway for the O2- generating system, we compared O2- production by newborn and adult bovine neutrophils stimulated with 3 different pkc agonists. When the phorbol ester phorbol 12-myristate 13-acetate (pma) was used, pkc-dependent O2- generation from newborn neutrophils was significantly reduced (P < 0.01) for all concentrations of pma tested (10, 100, and 500 ng/ml). In addition, newborn neutrophils had a significantly (P < 0.01) reduced lag time for O2- generation. Similar significantly (P < 0.01) reduced O2- generation from newborn neutrophils was observed with an additional phorbol ester (phorbol 12, 13-dibutyrate); lag times were not calculated for phorbol 12, 13-dibutyrate. When O2- generation was stimulated with a synthetic diacylglycerol analogue (1,2-dioctanoyl-sn-glycerol), less O2- was generated from both adult and newborn neutrophils than was obtained with the phorbol esters, and newborn neutrophils produced significantly (P < 0.01) less O2- only at 50 μM 1,2-dioctanoyl-sn-glycerol. To assess the importance of pkc and cyclic nucleotide-dependent protein kinases in the O2--related signal-transduction pathways of bovine neutrophils, we determined the influence of a pkc inhibitor, H-7, and a cyclic nucleotide-dependent protein kinase inhibitor, HA-1004, on the respiratory burst of adult and newborn bovine neutrophils. Preincubation of neutrophils (15 minutes) with 100 or 500 μM H-7 inhibited subsequent pma-induced O2- generation from newborn and adult neutrophils in a dose-dependent fashion, but preincubation with HA-1004 did not affect subsequent pma-induced O2- generation from either newborn or adult neutrophils. The pkc inhibitor, H-7 (100 and 500 μM), induced a significantly (P < 0.01) prolonged lag time in adult, but not newborn, neutrophils; HA-1004 had no effect on lag time. These results indicate that pkc, but not cyclic nucleotide-dependent protein kinase, is important in the signal-transduction pathway leading to O2- generation in appropriately stimulated adult and newborn bovine neutrophils, and that deficient respiratory burst activity in newborn neutrophils may be explained by altered activation of pkc.
Effects of topical administration of timolol maleate on intraocular pressure and pupil size in dogs
Authors: Wilkie David A. , Latimer Claire A.
Published: January 2024

Effects of topical administration of a single dose of timolol maleate on intraocular pressure (iop) and pupil diameter were evaluated in normotensive eyes of 11 clinically normal dogs over 12 hours (7:00 am to 7:00 pm). Mean (± sem) normal iop was 15.5 (± 1.1) mm of Hg and diurnal fluctuation was observed, with the highest iop seen in the morning. Mean normal pupil diameter was 8.5 (± 0.3) mm. Topical treatment with 0.5% timolol resulted in reduction of iop in the treated and nontreated eyes. Mean reduction of iop in the treated eye was 2.5 mm of Hg, a reduction of 16.1%, with maximal reduction of 3.7 mm of Hg. Mean reduction of iop in the nontreated eye was 1.4 mm of Hg, a reduction of 9.0%. The treated eye had reduced pupil diameter at 30 minutes after treatment, which persisted throughout the 12 hours of the study. Mean reduction of pupil diameter in the treated eye was 2.9 mm, a reduction of 34.1%. In addition, a contralateral effect on pupil diameter was seen in the nontreated eye, with mean reduction of 1.2 mm, a reduction of 14.1%.

Topical administration of timolol maleate resulted in reduction of iop and pupil diameter in treated and contralateral eyes, thus supporting the use of timolol for treatment of glaucoma in dogs. Miosis indicates possible β-adrenergic inhibition or β-adrenergic activation of the sphincter muscle. β-Adrenergic blockade would then result in miosis.
Effects of topical administration of timolol maleate on intraocular pressure and pupil size in cats
Authors: Wilkie David A. , Latimer Claire A.
Published: January 2024

Effects of topical administration of a single dose of timolol maleate, a nonselective β-adrenergic blocking agent, on intraocular pressure (iop) and pupil diameter were evaluated in the normotensive eyes of 10 clinically normal cats over 12 hours. Mean (± sem) normal iop was 17.1 (± 1.1) mm of Hg and diurnal fluctuation was observed, with the highest iop seen in the evening. Mean (± sem) normal pupil diameter was 10.1 (± 0.5) mm. Topical treatment with 0.5% timolol resulted in reduction of iop in treated and nontreated eyes. This effect was time-dependent and was first observed at 6 hours after treatment. Mean reduction of iop was 22.3% in the treated eye and 16.3% in the nontreated eye. The treated eye had reduced pupil diameter at 30 minutes after treatment, and miosis persisted throughout the 12 hours of the study. Mean reduction of pupil diameter was 38.7%. A contralateral effect on pupil diameter was not seen in the non-treated eye.

Topical administration of timolol maleate results in a reduction of iop in treated and contralateral eyes, which supports the use of timolol for treatment of glaucoma in cats. In addition, the treated eye becomes miotic. This effect may indicate β-adrenergic inhibition or α-adrenergic activation of the iris sphincter muscle. β-Adrenergic blockade would then result in miosis.
Abortifacient property of bovine herpesvirus type 1 isolates that represent three subtypes determined by restriction endonuclease analysis of viral DNA
Authors: Miller J. M. , Whetstone C. A. , Van Der Maaten M. J.
Published: January 2024

Bovine herpesvirus type 1 (bhv-1) isolates are classified into 3 subtypes by use of restriction endonuclease analysis. Isolates from aborted fetuses have been either subtype 1 or 2a, whereas subtype 2b viruses have not been associated with abortion. We assessed the abortifacient property of isolates representing each of the 3 bhv-1 subtypes by iv inoculation of heifers with the virus 25 to 27 weeks after breeding. Three heifers were given Cooper (subtype 1) isolate, 3 heifers were given FI (subtype 2a) isolate, and 5 heifers were given K22 (subtype 2b) isolate. All heifers developed fever and viremia 2 to 5 days after inoculation. Heifers given Cooper or FI isolate aborted between 17 and 85 days after inoculation. The 5 heifers given K22 isolate delivered full-term calves. Placenta was obtained from 4 of the 5 heifers, and K22 virus was isolated from each placenta. Four calves had bhv-1 neutralizing antibody in precolostral serum, with titer ranging from 1:4 to 1:512.
Effect of colostrum ingestion on gamma-glutamyltransferase and alkaline phosphatase activities in neonatal pups
Authors: Center Sharon A. , Randolph John F. , ManWarren Trenna , Slater Margaret
Published: January 2024

Analysis of hepatic enzyme activities in serum samples from 1- to 3-day-old pups revealed alkaline phosphatase (alp) activities that were 30 times higher and γ-glutamyltransferase (ggt) activities that were 100 times higher than activities in clinically normal adult dogs. A study was conducted to investigate high enzyme activity in pups and to determine whether there is any association between serum enzyme activity and colostrum ingestion, passive transfer of maternal serum enzyme (in colostrum or in utero), or excessive renal or hepatic tissue enzymes. Serum enzyme activity was quantified in 15 neonatal pups before and after ingestion of colostrum and in 3 colostrum-deprived neonates fed a milk substitute. Serum samples were collected on postpartum days 0, 1, 10, 15, and 30. Enzyme activity was also quantified in serum from pregnant and lactating bitches (collected on days -2, 0, 1, 10, 30), hepatic and renal tissue from clinically normal adult dogs and 1-day-old pups, colostrum, milk (collected on days 10 and 30), and milk replacer.

Significant (P < 0.01) differences in serum ggt and alp activities between colostrum-deprived and suckling pups did not exist before initial feeding. Significant (P < 0.001) increases in serum ggt and alp activities developed within 24 hours in suckling pups, but not in the colostrum-deprived pups. At 10 and 30 days after birth, serum ggt and alp activities were less than values before suckling in all pups.

Enzyme activities in bitches’ serum remained within the normal range for adult dogs throughout whelping and lactation. Renal ggt and alp activities were substantially greater than hepatic enzyme activities in neonates and adults. Renal tissue from adults contained 3 times greater ggt and 2 times greater alp activities than that from neonates. Hepatic tissue from neonates contained 5 times more ggt activity than did hepatic tissues from clinically normal adults; however, hepatic alp activity was similar in adults and neonates.

Colostrum and milk had substantially higher enzyme activities than did bitches’ serum. Activities of ggt and alp in milk were 100 times and 10 times greater, respectively, than activities in serum through day 10. By day 30, ggt and alp activities in milk were less than before suckling. Enzyme activity was not detected in the milk substitute.

These studies reveal an association between colostrum ingestion by suckling and acute, profound increases in serum ggt and alp in 1- to 3-day-old pups. Although this phenomenon might be useful as an indicator of colostrum ingestion, it precludes the diagnostic use of either enzyme as an indicator of hepatobiliary disease in 3-day-old pups.
Comparison of the hemodynamic effects of halothane alone and halothane combined with epidurally administered morphine for anesthesia in ventilated dogs
Authors: Valverde Alexander , Dyson Doris H. , Cockshutt Joanne R. , McDonell Wayne N. , Valliant Anne E.
Published: January 2024

The hemodynamic effects of 1.5 minimal alveolar concentration of halothane alone (1.6% end-tidal) and 1.5 minimal alveolar concentration of halothane (1.1% end-tidal concentration) combined with epidurally administered morphine were compared during controlled ventilation in 10 dogs used on 2 occasions and randomly allocated to 2 groups. Arterial blood pressure, cardiac index, stroke volume, left ventricular work, and pulmonary arterial pressure were significantly (P < 0.05) higher in dogs of the morphine-treated group before administration of morphine. After epidural administration of morphine (0.1 mg/kg of body weight diluted in 0.26 ml of saline solution/kg), hemodynamic changes were not observed, and the aforementioned variables remained significantly (P < 0.05) higher than values in dogs of the halothane only group. Compared with halothane (1.6%) alone, the reduction in halothane end-tidal concentration (1.1%) associated with epidurally administered morphine is beneficial in maintaining hemodynamic function.
Cardiovascular and respiratory effects of thiopental administration in hypovolemic dogs
Authors: Ilkiw Jan E. , Haskins Steve C. , Patz John D.
Published: January 2024

The cardiopulmonary effects of thiopental sodium were studied in hypovolemic dogs from completion of until 1 hour after administration of the drug. Hypovolemia was induced by withdrawal of blood from dogs until mean arterial pressure of 60 mm of Hg was achieved. After stabilization at this pressure for 1 hour, 8 mg of thiopental/kg of body weight was administered iv to 7 dogs, and cardiopulmonary effects were measured. After blood withdrawal and prior to thiopental administration, heart rate and oxygen utilization ratio increased, whereas mean arterial pressure, mean pulmonary arterial pressure, central venous pressure, pulmonary wedge pressure, cardiac index, oxygen delivery, mixed venous oxygen tension, and mixed venous oxygen content decreased from baseline. Three minutes after thiopental administration, heart rate, mean arterial pressure, mean pulmonary arterial pressure, pulmonary vascular resistance, and mixed venous oxygen tension increased, whereas oxygen utilization ratio and arterial and mixed venous pH decreased from values measured prior to thiopental administration. Fifteen minutes after thiopental administration, heart rate was still increased; however by 60 minutes after thiopental administration, all measurements had returned to values similar to those obtained prior to thiopental administration.
Comparative study of the pharmacokinetics of alfentanil in rabbits, sheep, and dogs
Authors: Ilkiw Jan E. , Benthuysen James A. , McNeal D.
Published: January 2024

The central arterial pharmacokinetics of alfentanil, a short-acting opioid agonist, were studied in rabbits, sheep, and dogs after short-duration infusion of the drug. Alfentanil was infused until a set end point (high-amplitude, slow-wave activity on the eeg) was reached. This required a larger alfentanil dose and a higher alfentanil arterial concentration in sheep, compared with rabbits and dogs. The plasma concentration-time data for each animal were fitted, using nonlinear regression, and in all animals, were best described by use of a triexponential function. In this study, differences in the disposition kinetics of alfentanil among the 3 species were found for only distribution clearance and initial distribution halflife. In dogs, compared with rabbits and sheep, the first distribution half-life was longer, probably because of pronounced drug-induced bradycardia (mean ± SD, 48 ± 21 beats/min). Distribution clearance was faster in sheep, compared with dogs, also probably because of better blood flow in sheep. Elimination half-life was similar in all species (rabbits, 62.4 ± 11.3 minutes; sheep, 65.1 ± 27.1 minutes; dogs, 58.3 ± 10.3 minutes). This rapid half-life resulted from a small steady-state volume of distribution (rabbits, 908.3 ± 269.0 ml/kg; sheep, 720.0 ± 306.7 ml/ kg; dogs, 597.7 ± 290.2 ml/kg) and rapid systemic clearance (rabbits, 19.4 ± 5.3 ml/min/kg; sheep, 13.3 ± 3.0 ml/min/kg; dogs, 18.7 ± 7.5 ml/min/kg). On the basis of these pharmacokinetic variables, alfentanil should have short duration of action in rabbits, sheep, and dogs. This may be beneficial in veterinary practice where rapid recovery would be expected after bolus administration for short procedures or after infusion for longer procedures.
Immunocytochemical study of tissues from clinically normal dogs and of neoplasms, using keratin monoclonal antibodies
Authors: Sandusky G. E. , Wightman K. A. , Carlton W.W.
Published: January 2024

Three commonly used keratin monoclonal antibodies (mab)-AE1:AE3, CAM 5.2, and MAK-6—were compared with routinely used cytokeratin antibody. The expression of these antibodies was analyzed in several tissues obtained from clinically normal dogs and in a variety of neoplasms from dogs. Using appropriate enzymatic digestion, paraffin-embedded tissues processed in routine manner retained their typical keratin expression. Differentiated and poorly differentiated epithelial neoplasms, lymphomas, and melanomas were studied by use of the avidin- biotin-peroxidase technique. All 4 of the aforementioned antibodies had similar staining profiles. Of 3 anaplastic carcinomas, 2 had positive reaction to all 4 antibodies. All lymphomas, plasma cell tumors, and amelanotic melanomas had negative reaction to MAK-6, CAM 5.2, AE1:AE3, and cytokeratin mab. Three basal cell epitheliomas had positive reaction to all 4 antibodies, whereas 1 basal cell tumor with a solid pattern had negative staining reaction. Two carcinoids had negative reaction to all markers and 1 of 2 malignant chemodectomas and 1 transitional cell carcinoma had staining reaction to only AE1:AE3 mab. Comparing the 4 antibodies, use of AE1:AE3 mab produced the strongest staining intensity followed by cytokeratin, MAK-6, and CAM 5.2 mab. All 4 antibodies had low background staining. In conclusion, AE1:AE3 and MAK-6 mab are as useful as cytokeratin mab for identification of poorly differentiated epithelial neoplasms in dogs and cats.
Effect of midazolam preanesthetic administration on thiamylal induction requirement in dogs
Authors: Tranquilli Wm. J. , Graning L. M. , Thurmon J. C. , Benson G. J. , Mourn S. G. , Lentz E. L.
Published: January 2024

The thiamylal sparing effect of midazolam was studied in 30 healthy Beagle and mixed-breed dogs. Using a replicated Latin square design, all dogs were given placebo (saline solution) and 0.025, 0.05, 0.1, and 0.2 mg of midazolam/ kg of body weight prior to iv administration of thiamylal sodium. The 0.1 and 0.2 mg/kg dosages significantly decreased the amount of thiamylal required to obtund swallowing reflex and easily achieve endotracheal intubation. Midazolam at 0.1 and 0.2 mg/kg reduced thiamylal requirement by 16.4% and 18.9%, respectively, whereas the 0.05 mg/kg dosage decreased thiamylal requirement by only 6.8%. The 0.2 mg/kg dosage did not further decrease thiamylal requirement beyond that achieved with the 0.1 mg/kg dosage of midazolam. This study demonstrates that the preanesthetic iv administration of midazolam reduces the thiamylal dose necessary to accomplish intubation. The optimal preanesthetic dosage (lowest dosage with significant effect) was 0.1 mg/kg.
Effects of sodium hyaluronate on tendon healing and adhesion formation in horses
Authors: Gaughan Earl M. , Nixon Alan J. , Krook Lennart P. , Yeager Amy E. , Mann Kenneth A. , Mohammed Hussni , Bartel Donald L.
Published: January 2024

Sodium hyaluronate reduces adhesions after tendon repair in rodents and dogs, and has been used in limited clinical trials in people. To evaluate its effect on tendon healing and adhesion formation in horses and to compare these effects with those of a compound of similar viscoelastic properties, a study was performed in horses, using a model of collagenase injection in the flexor tendons within the digital sheath.

Eight clinically normal horses were randomly allotted to 2 groups. Adhesion formation between the deep digital flexor tendon and the tendon sheath at the pastern region was induced in the forelimbs of all horses. Using tenoscopic control, a 20-gauge needle was inserted into the deep digital flexor tendon of horses under general anesthesia and 0.2 ml of collagenase (2.5 mg/ml) was injected. The procedure was repeated proximally at 2 other sites, spaced 1.5 cm apart. A biopsy forceps was introduced, and a 5-mm tendon defect was created at each injection site. Group-A horses had 120 mg of sodium hyaluronate (NaHA) gel injected into the tendon sheath of one limb. Group-B horses had methylcellulose gel injected at the same sites. The contralateral limbs of horses in both groups served as surgical, but noninjected, controls. Horses were euthanatized after 8 weeks of stall rest.

Ultrasonographic evaluation revealed improved tendon healing after NaHa injection, but no difference in peritendinous adhesion formation. Tendon sheath fluid volume and hyaluronic acid (ha) content were greater in NaHA-treated limbs. Gross pathologic examination revealed considerably fewer and smaller adhesions when limbs were treated with NaHA. However, significant difference in pull-out strengths was not evident between NaHA-treated and control limbs. Histologically, the deep digital flexor tendon from the NaHA-treated limbs had reduced inflammatory cell infiltration, improved tendon structure, and less intratendinous hemorrhage. Treatmerit with methylcullulose had no significant effect on tendon healing, adhesion size, quantity, or strength or on the volume and composition of the tendon sheath fluid. Sodium hyaluronate, administered intrathecally, appears to have a pharmaceutically beneficial action in this collagenase-induced tendinitis and adhesion model in horses.
Effect of left hepatic vein ligation on hepatic circulation, function, and microanatomy in dogs
Authors: Payne John T. , Martin Robert A. , Moon Martha L. , Saunders Geoffrey K. , Donaldson Lydia , Richey Megan , Clutton Richard E. , Shires Peter K.
Published: January 2024

Eighteen healthy dogs were allotted to 3 groups (n = 6 dogs each). All dogs were evaluated at the beginning of the study by complete physical examination; total and differential WBC counts; serum biochemical analysis (alanine transaminase and alkaline phosphatase activities and bilirubin and albumin concentrations); sulfobromophthalein excretion, ammonia tolerance, and glucagon response testing; portal and intraparenchymal pressure determinations; operative mesenteric portography; and histologic assessment of hepatic biopsy specimens.

The left hepatic vein was ligated completely in dogs of groups 1 and 2. Group-3 (control) dogs had a ligature placed loosely around the left hepatic vein. Dogs of groups 1 and 3 were reevaluated 24 hours after surgery by use of the aforementioned hematologic and biochemical tests. Group-1 dogs were reevaluated by use of portal and intraparenchymal pressure determinations, jejunal vein portography, and complete necropsy at 48 hours after surgery. At 4 weeks after surgery, dogs of groups 2 and 3 were reevaluated by use of all aforementioned tests.

Results indicated transient hepatic congestion, which resolved by the fourth postoperative week. Longstanding effect on hepatic structure, circulation, or function was not found. We concluded that left hepatic vein ligation in clinically normal dogs does not cause severe or permanent liver damage.
Association between solar radiation and ocular squamous cell carcinoma in cattle
Authors: Anderson David E. , Badzioch Michael
Published: January 2024

The association between ocular squamous cell tumors and various measures of solar radiation was evaluated for 2,775 contemporaneous Hereford cattle. The animals were from 34 herds located in 21 states in the United States and in one Canadian province. Examinations and photographs were made of the eyes of all cows and heifers in a herd; 33 herds were examined between June and August 1957 and 1 herd was examined in 1958. Solar radiation was measured by altitude and mean annual hours of sunshine applying to an individual herd, and global radiation, a cloudiness index, and elevation of nearby National Weather Service stations. All measures of solar radiation provided evidence of a significant association between increasing risks of developing cancer eye and increasing levels of radiation; adjustments were made for possible confounding effects of age and corneoscleral pigmentation. Associations were evident whether affliction was defined as the occurrence of any type of tumor (ie, plaque, papilloma, or carcinoma), or as the occurrence of only papilloma or carcinoma. Average ages of affected cattle also tended to be lower at high radiation levels than at low levels, further supporting the hypothesis that solar radiation has an important role in the development of this disease. In view of the heritability of eye pigmentation and its inhibitory effect on lesions, cancer eye may be controlled by selective breeding for increased pigmentation in and around the eye to afford protection against the harmful effects of incident uv radiation.
Evaluation of Campylobacter jejuni colonization of the domestic ferret intestine as a model of proliferative colitis
Authors: Bell Judith A. , Manning Dean D.
Published: January 2024

Forty 3- to 17-week old domestic ferrets, including 2 gnotobiotes, were inoculated orally and/or rectally with 106 to 109 colony-forming units of 1 or more of 4 strains of Campylobacter jejuni, 3 of mink and 1 of human origin. Feeding or gavage of any of the 4 strains, in milk or broth, with or without preinoculation sodium bicarbonate treatment to neutralize stomach acid, induced colonization in 38/40 ferrets; diarrhea lasted 2 to 4 days in conventional kits, 6 days in gnotobiotes. Bacteremia was detected in 4 of 18 tested, 2 to 5 days after inoculation. Two strains caused no more severe disease or prolonged colonization after 3 serial iv passages in kits than they did before passage. Multiple inoculations with a given strain resulted in progressively briefer colonization and milder disease, but subsequent inoculation with a different strain induced colonization and gastrointestinal disease similar to a primary infection. Five kits inoculated rectally after 4 previous homologous inoculations were resistant to colonization as well as to disease. Agglutinin titers of ferrets inoculated orally or rectally once were low or undetectable, but increased in response to repeated inoculation. Pretreatment with a 1% formalin enema caused mild colon irritation without clinical or histologic evidence of proliferative colitis in ferrets concurrently inoculated orally and/or rectally, whether or not they had preexisting antibodies to any strain of C jejuni. Histologic examination of tissues revealed leukocytic infiltration of intestinal lamina propria in 29 of 35 infected kits and 5 of 8 noninfected controls, and cryptosporidiosis in 5 infected kits plus 1 control. Examination of silver-stained sections of intestine from 15 infected ferrets revealed Campylobacter like organisms on the surface of, but never inside, epithelial cells. The lack of characteristic gross or histologic lesions suggested that C jejuni is not, by itself, responsible for proliferative colitis in ferrets.
Epidemiologic factors and isotype-specific antibody responses in serum and mucosal secretions of dairy calves with bovine coronavirus respiratory tract and enteric tract infections
Authors: Heckert Robert A. , Saif Linda J. , Myers Greg W. , Agnes Arden G.
Published: January 2024

Blood, feces, and nasal swabs specimens were collected 12 to 24 hours after birth and then 3 times/week (blood only once per week) from one group of 10 calves until they were 10 weeks old and from a second group of 10 calves until they were 10 to 20 weeks old. Colostrum was collected from all calves’ dams and tears from 5 randomly selected calves in the first group. All fecal and nasal specimens were assayed for bovine coronavirus (bcv) antigens by elisa. Nasal epithelial cells were examined for bcv antigens by direct immunofluorescence. Isotype antibody titers to bcv in all samples from 5 calves in group 1 were evaluated by elisa. Zinc sulfate turbidity (zst) values were determined on the first serum samples taken from all calves in group 1. To determine whether any correlation existed between zst values, isotype antibody titers to bcv (12 to 24 hours after birth), number of respiratory sick days, number of enteric sick days, or days to first shedding of virus, a Spearman rank order correlation coefficient was done.

Bovine coronavirus respiratory tract and enteric tract infections were common on this farm. Most initial infections developed when calves were 1 to 3 weeks old; however, there were also multiple incidences of shedding of viral antigens or seroconversions at later times during the study. Persistence of infection or reinfection of the upper respiratory tract with bcv was common.

Colostral antibody titers to bcv (IgG1) were in all cows at moderate amounts; however, calf serum antibody titers and zst values (12 to 24 hours after birth) were highly variable. Significant correlations were found between zst values and bcv IgG1, IgG2, and IgA serum antibody titers (12 to 24 hours after birth); and number of respiratory sick days and zst values, IgG1, IgG2, and IgA serum antibody titers (12 to 24 hours after birth). All calves in group 1 had serum antibody IgM titer increases to bcv when they were 1 to 2 weeks old and many had subsequent IgA, IgG2, and IgG1 serum antibody titer increases in the first 4 weeks. Six calves had a second serum antibody titer increase with IgM or IgA isotypes when they were 5 to 9 weeks old. In the second group, IgM, IgA, and IgG serum antibody titers were increased > fourfold in 6 of 9, 8 of 9, and 5 of 9 calves, respectively. Most calves had passive IgG1 bcv antibodies in their nasal secretions or tears when they were 1 week old and all calves had at least one transient increase in active IgM antibody titers followed by a sharp and persistent increase in IgA titers. All calves had bcv antibodies (IgG1, IgA, or IgM) in their feces when they were 1 week old and at least one transient increase in fecal IgM (4 of 5 calves) or IgA (3 of 5 calves) antibody titers in the 9-week period.
Comparison of four methods of estimating glomerular filtration rate in cats
Authors: Rogers Kenita S. , Komkov Andrea , Brown Scott Anthony , Lees George E. , Hightower Dan , Russo Elizabeth A.
Published: January 2024

Four methods of evaluating renal function were performed in 6 cats anesthetized with halothane in oxygen. Glomerular filtration rate (gfr) was measured simultaneously in each cat by exogenous creatinine clearance (ecc), bolus inulin clearance, and 99mTc(Sn)-diethylenetriaminepentaacetic acid (dtpa) clearance determined by 2 different methods. In the first dtpa clearance method (dtpa-1), we measured radioactivity in serial blood specimens to construct plasma disappearance curves for calculation of gfr. In the second dtpa clearance method (dtpa-2), we used serial external head counts of radioactivity and a single blood specimen to construct plasma disappearance curves for calculation of gfr. Bolus inulin clearance was calculated from plasma disappearance curves using a 1-compartment open pharmacokinetic model (IN- 1) and a 2-compartment open pharmacokinetic model (IN- 2). Glomerular filtration rates were measured over 3 hours, for creatinine and dtpa methods, and over 4 hours for the inulin methods.

The gfr obtained with the reference method (ecc) was 2.56 ± 0.61 ml/min/kg of body weight (mean ± SD). Values for gfr determined by ecc and dtpa-1 were significantly correlated (r = 0.852; P ≤ 0.05). Correlation between ecc and dtpa 2 was not as good (r = 0.783; P ≤ 0.10), but the 2 dtpa methods significantly correlated with one another (r = 0.897; P ≤ 0.05). Regardless of the method of calculation, bolus inulin clearance was poorly correlated with ecc (IN-1: r = 0.538, P ≥ 0.10; in-2: r = 0.430, P ≥ 0.10) and dtpa-1 in-1: r = 0.601, P ≥ 0.10; in-2: r = 0.625, P ≥ 0.10). The 2 methods of calculating inulin clearance were highly correlated (r = 0.927; P ≤ 0.01). The dtpa clearance calculated from directly measured plasma disappearance curves (dtpa-1) compared favorably with ecc as an estimate of gfr and appears to be a safe, reliable, and less invasive method of determining gfr in cats.
Use of two enzyme-linked immunosorbent assays to monitor antibody responses in swine with experimentally induced infection with porcine epidemic diarrhea virus
Authors: van Nieuwstadt A. P. , Zetstra T.
Published: January 2024

A blocking elisa was developed to detect antibodies directed against porcine epidemic diarrhea virus (pedv). The pedv antigen was first incubated with dilutions of test sera. Any antigen that was not blocked by antibodies in the serum was assayed in a double-antibody sandwich elisa, using 2 monoclonal antibodies directed against different antigenic sites on pedv as capture and detecting antibodies, respectively. The blocking elisa was compared with a fixed-cell elisa that used monolayers of Vero cells infected with pedv prototype strain CV777 as a solid phase and a conjugate of an IgG-specific monoclonal antibody for antibody detection. Pigs were inoculated with pedv strain CV777 or 1 of 2 field isolates, and antibody responses were measured by use of the 2 tests. Antibodies were detected by the blocking elisa as early as postinoculation day 7 and, by the fixed-cell elisa, as early as postinoculation day 14. From day 14 on, antibody titers for both tests correlated highly. Titers for the fixed-cell elisa were 5.4 times higher than those for the blocking elisa. The latter technique is easier to perform and discriminates well between infected and noninfected pigs, which makes this test useful for routine diagnosis and serologic surveys of porcine epidemic diarrhea.
N-acetyl-β-d-glucosaminidase as a predictor of milk loss and recovery after clinical mastitis
Authors: Wilson David J. , Bartlett Paul C. , Kirk J. H. , Mellenberger R. W. , Mather E. C.
Published: January 2024

Milk samples were collected at onset of 508 episodes of clinical mastitis on a 1,700-cow dairy farm in Michigan. Daily milk production and disease events were recorded for all cows in the herd. Despite statistical association with severity of mastitis, this association was too weak for Nacetyl-(β-d-glucosamimdase (NAGase) activity to be of great value as a prognostic test for clinical mastitis. High milk NAGase activity was significantly (P < 0.0001) associated with: increased duration of treatment; increased duration of clinical signs of mastitis; decreased daily milk production; and increased risk of the cow being culled because of mastitis. The NAGase value was combined with days in milk production, baseline milk production before mastitis onset, parity, and season of onset to predict the outcome of clinical cases as measured by the first 3 aforementioned variables. Statistical models explained little of the variability among cows in duration of treatment (R2 = 0.11), duration of clinical signs of infection (R2 = 0.11), and milk production change (R2 = 0.09).
Effects of a proprietary topical medication on wound healing and collagen deposition in horses
Authors: Madison John B. , Hamir Amirali N. , Ehrlich H. Paul , Habennan Jules , Topkis Virginia , Villasin Jose V.
Published: January 2024

Full-thickness skin wounds were created on the dorsum of both metacarpi in 8 horses. Three topical treatment regimens were studied. All wounds were bandaged with a nonadherent dressing, which was held in place with a snug elastic wrap. Group-A wounds were treated with a proprietary topical wound medication that consisted of a spray and an ointment. Group-B wounds were treated with the same regimen, except the putative active ingredients in the ointment were omitted. Group-C wounds were treated with a dry nonadherent bandage only. Wound dressings were changed every day and the limbs were photographed every other day until the wounds were healed. Specimens of normal skin and biopsy specimens of healed wounds were examined histologically and were assayed for hydroxyproline content. Wound healing measurements quantitated for each wound were number of days to healing, maximal wound size attained, day wound contraction commenced, day epithelium first noticed, rate of wound contraction, final wound size, and fraction of the wound that healed by contraction. The cosmetic appearance of the healed wounds was also graded.

Significant differences were not noticed in hydroxyproline content, histologic appearance, or any of the wound healing measurements between treatment groups. The cosmetic appearance of healed group-A and -B wounds was significantly better than the appearance of group-C wounds. The topical treatment regimens studied neither enhanced nor inhibited wound healing in this study.
Culture and morphologic features of small intestinal mucosal explants from weaned pigs
Authors: Nietfeld Jerome C. , Tyler David E. , Harrison Lenn R. , Cole John R. , Latimer Kenneth S. , Crowell Wayne A.
Published: January 2024

Small intestinal explants from weaned pigs were cultured under a variety of conditions. Explants maintained villus-to-crypt ratio between 1:1 and 1.5:1 for 48 hours. The mucosal epithelium remained well preserved and retained good cellular morphologic features, as determined by light and electron microscopy. Between 48 and 72 hours, considerable mucosal degeneration was evident. Best results were obtained when the explants were cultured on a rocking platform placed in an atmosphere of 95% O2 and 5% CO2, using supplemented rpmi 1640 cell culture medium.
Detection of bovine viral diarrhea virus, using degenerate oligonucleotide primers and the polymerase chain reaction
Authors: Ward Pearse , Misra Vikram
Published: January 2024

A technique for detection of bovine viral diarrhea virus (bvdv) from circulating blood leukocytes, using the polymerase chain reaction, is described. The published nucleotide sequences of 2 strains of bvdv and that of hog cholera virus were aligned and the information was used to design oligonucleotides coding for 2 regions of amino acid homology. The oligonucleotides were a mixed population including all possible codons for the conserved amino acids. These degenerate oligonucleotides were used in the polymerase chain reaction to detect viral rna in cells infected in vitro, or in circulating blood leukocytes from infected animals. Virus was detected in over 60 samples from diverse isolates. The detection of bvdv by the polymerase chain reaction is a rapid, sensitive, and specific technique, which represents an improvement over existing technology.