bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of the API 20E System To Identify Non-Enterobacteriaceae from Veterinary Medical Sources
Authors: Collins Michael T. , Swanson Evryll C.
Published: February 2025

The capability of the API 20E system to identify gram-negative nonfermenters and nonenteric fermenters was evaluated for 272 isolates from veterinary sources. Two different methods were used for interpreting the carbohydrate fermentation reactions on the strip. In method I, weakly fermented (yellow-green) carbohydrates were considered positive for all oxidase-positive organisms, and in method II, yellow-green carbohydrates were considered positive for all organisms requiring incubation for 48 hours. By both methods, the API system correctly identified 62% of the isolates. With method I, 31% of the isolates were misidentified and 6% were not identified. With method II, 21% of the isolates were misidentified and 17% received no identification. Organisms most affected by these 2 methods of interpretation were Pasteurella and Actinobacillus.

Identifications reached by the API system were also compared with identifications made by veterinary diagnostic laboratories. The frequency of identifications agreements was not significantly affected by the method of API carbohydrate fermentation reaction interpretation. Generally, 30% of the identifications agreed (diagnostic laboratories vs API) when using only the API Index, whereas 51% agreed when the entire API computer data base identifications were included.

The type of identification disagreements between diagnostic laboratories and the API system, however, was significantly affected by the method of API strip interpretation. With method I, 42% of the identifications were different and 6% were not in the API data base. With method II, 33% of the identifications were different and 17% were not in the API data base.

Biotype differences between human and veterinary isolates were also compared. Significant differences between the predicted and actual reactions were noted for Pseudomonas aeruginosa and Bordetella bronchiseptica; however, these differences did not affect their correct identification to the API Index. For Pasteurella multocida, most profile numbers were not listed in the API Index because of differences in the actual vs predicted oxidase and nitrate reduction reactions; however, they were correctly identified with the total computer data base.
Light Microscopic, Scanning Electron Microscopic, and Histomorphometric Evaluation of Mycoplasma gallisepticum-Induced Airsacculitis in Chickens
Authors: Trampel D. W. , Fletcher O. J.
Published: February 2025

Significant increases in air-sac volume and in numbers of epithelial cells, heterophils, mononuclear cells, fibrin, blood vessels, and connective tissue components occurred in chickens during the 21-day period after they were inoculated with live Mycoplasma gallisepticum (mg) organisms. Neither filtered mg growth medium nor Frey's medium was capable of inducing lesions comparable with those produced by live mg.

Scanning electron microscopic and light microscopic observations identified multiple focal accumulations of exudate associated with luminal epithelial cell damage. An increase in number of type II sacculocytes after mg infection was shown by scanning electron microscopy.
Introduction and Reisolation of Selected Gram-Positive Bacteria from Fermented Edible Wastes
Authors: Talkington F. D. , Shotts E. B. , Wooley R. E. , Whitehead W. K. , Dobbins C. N.
Published: February 2025

A fermentation process using Lactobacillus acidophilus added to edible food wastes was evaluated for its bactericidal action on selected gram-positive organisms. The Lactobacillus fermentation converts food wastes into an animal feed ingredient. In this study, 5 gram-positive bacteria of zoonotic importance were individually tested. These organisms were: Group E Streptococcus, Erysipelothrix rhusiopathiae, Clostridium perfringens, Corynebacterium pseudotuberculosis, and Listeria monocytogenes.

For each experiment, Lactobacillus was first mixed into ground waste; one of the test organisms was then inoculated and mixed. This mixture was divided among eight 5.5-L containers and incubated (duplicates) at 5 C, 10 C, 20 C, and 30 C for 96 hours. Internal waste temperature, reduction-oxidation, and pH were monitored. Waste samples were taken initially and at subsequent 24-hour periods.

Qualitative and quantitative recoveries of the test bacteria were attempted for each sample. Group E Streptococcus was reisolated in increasing numbers at all temperatures throughout the fermentation period. Erysipelothrix rhusiopathiae was recovered throughout the 96-hour period at 5 C; at 10 C it was recovered at 24 hours but not at 48 hours. Erysipelothrix rhusiopathiae was killed by 24 hours at 20 C and 30 C fermentation temperatures. Clostridium perfringens survived the entire test period at 5 C, 10 C, and 20 C; it was killed by 72 hours at 30 C. Neither Corynebacterium pseudotuberculosis nor Listeria monocytogenes was reisolated at any temperature at any time.
Serum Lysozyme (Muramidase) Activity in Dogs with Neoplastic Disease
Authors: Feldman Bernard F. , Madewell Bruce R. , Miller Robert B.
Published: February 2025

The lysozyme (muramidase) activity was measured in the sera of 84 dogs with neoplastic disease. Neoplasms included 32 lymphomas, 13 primary bone neoplasms, 5 melanomas, 5 thyroid neoplasms, 9 soft tissue sarcomas, 5 mast cell sarcomas, and 15 carcinomas. The sera from 21 healthy dogs served as controls.

Dogs with neoplastic disease had significantly (P < 0.005) higher serum lysozyme activity than did the healthy controls. For lymphosarcoma, dogs with clinical signs of systemic disease had significantly higher serum lysozyme activity than did dogs without clinical signs. For bone neoplasms, dogs with metastatic disease had higher serum lysozyme activity than did dogs without metastasis. Increased lysozyme activity may be a useful marker of macrophage-mediated host responses to neoplasms in dogs.
Effect of Streptococcus pneumoniae Infection in Rats on Hepatic Water Content, Electrolyte Concentration, and Chemical Composition
Authors: Little J. S. , Rill W. L. , Hawley H. P. , Liu C. T.
Published: February 2025

Total hepatic water content, dry weight, protein, lipid, carbohydrate, RNA, DNA, and electrolyte concentrations were determined in control and Streptococcus pneumoniae-infected rats. During infection, there was a significant (P = 0.001) increase in total liver weight. This increase was the result of increased total liver water content and increased total liver dry weight. Intracellular water content, diameter of hepatocytes, and all measured constituents of hepatic dry weight, excluding DNA, increased significantly (P varied from 0.05-0.001) during infection. Concentrations of liver Na+ and Cl- increased significantly (P varied from 0.05-0.005), whereas the concentration of liver K+ decreased significantly (P = 0.01). Seemingly, there is an enlargement of hepatocytes due to increased intracellular water and increased dry weight during pneumococcal infection in the rat. The mechanism of these liver changes may be due, in part, to a shift of Na+ and K+ across liver cell plasma membranes.
Lymphocyte Function and Cell-Mediated Immunity in Pigs with Experimentally Induced African Swine Fever
Authors: Sanchez-Vizcaino J. M. , Slauson D. O. , Ruiz-Gonzalvo F. , Valero F.
Published: February 2025

Twenty-five pigs inoculated with African swine fever virus were studied for the development of changes in lymphocyte numbers and function. The results indicated that lymphopenia and decreased percentage of circulating T-lymphocytes occurred as early as 7 days after the pigs were inoculated. These were accompanied by depressed lymphocyte function, as measured by mitogen- or antigen-induced blastogenesis.

There were proportionately greater decreases in T-lymphocyte numbers and function than were found for B-lymphocytes. Studies of phagocytic cell function revealed decreased phagocytic function for peripheral blood monocytes and unchanged (norma) neutrophil function. Depressed T-lymphocyte function occurred in pigs with acute and subacute infections, indicating depression of cellular immune function.
Histopathologic Response of the Bovine Mammary Gland to Experimentally Induced Staphylococcus aureus Infection
Authors: Nickerson Stephen C. , Heald C. W.
Published: February 2025

At 2 and 10 days after Staphylococcus aureus mastitis was induced in dairy cattle, mammary tissue from 2 zones in infected quarters was morphometrically compared with similar zones in contralateral control quarters. In comparison with control tissue, infected tissue exhibited more interalveolar stromal area, reduced alveolar luminal area, and more damaged and involuted alveolar epithelial area. These changes appeared more advanced at 10 days than at 2 days after infection was induced, indicating that by day 10, glandular parenchyma was losing secretory potential. Quarter zones differed greatly in the responses to infection. Parenchyma taken from a zone of an infected quarter close to the glandular part of the lactiferous sinus appeared to undergo involution more rapidly than a zone further from the sinus. Involuted parenchyma displayed reduced secretory activity, diminished luminal areas, and abundant connective tissue. A portion of nonsecretory epithelia taken from involuted areas of a zone close to the glandular part of the sinus stained for presence of immunoglobulin A.
Adverse Cardiovascular Effects of Oxytetracycline Preparations and Vehicles in Intact Awake Calves
Authors: Gross D. R. , Dodd K. T. , Williams J. D. , Adams H. R.
Published: February 2025

SUMMARY AND CONCLUSIONS

Comparisons were made of cardiovascular effects in intact, awake, previously instrumented calves given the following oxytetracycline (oxy) preparations and components: polyvinylpyrrolidine vehicle (pvp), oxy HCl in pvp (oxy-pvp), oxy HCl (USP) in saline solution, propylene glycol, 77.8% (pg), propylene glycol vehicle (pgv), and oxy HCl in pgv (oxy-pgv). The 3 preparations containing pg caused significant increases in pulmonary arterial pressures and significant decreases in cardiac output and stroke volume. Aortic pressures were significantly decreased, as were heart rates. Both pulmonic and systemic resistances were significantly increased. There were no direct effects measured on left ventricular contractility. The aqueous oxy caused no significant changes. The pvp preparation and vehicle caused no changes in pulmonary pressures, pulmonary resistance, cardiac output, or stroke volume. Significant increases were observed in aortic pressure, heart rate, and systemic resistance. Left ventricular contractility was not changed. Seemingly, the pg-induced changes were a result of histamine release which did not appear to be dependent on prior sensitization of the calves.
Cytotoxic Effects of Pasteurella haemolytica on Bovine Neutrophils
Authors: Berggren K. A. , Baluyut C. S. , Simonson R. R. , Bemrick W. J. , Maheswaran S. K.
Published: February 2025

The interaction of logarithmic- and stationary-phase organisms of Pasteurella haemolytica with bovine neutrophils was evaluated by an opsonocytophagic assay. Only 5% to 8% of the logarithmic-phase P haemolytica 12296 organisms opsonized with normal bovine serum or antiserum were phagocytized. Results from cytotoxicity assays, using the 51Cr release technique and the trypan blue exclusion test, indicated that the logarithmic-phase organisms liberated a soluble material that was cytotoxic to neutrophils and destroyed their phagocytic capabilities. This hypothesis was verified by transmission electron microscopy studies. Opsonized stationary-phase organisms were completely phagocytized and degraded when exposed to neutrophils at a bacteria/neutrophil ratio of 10:1. However, at a high bacteria/neutrophil ratio of 100:1, only 31% of the bacteria were phagocytized. Prolonged incubation of this mixture resulted in cytotoxic changes in the neutrophils. Seemingly, excess unphagocytized bacteria liberated a soluble substance that was toxic to neutrophils. These findings were confirmed by cytotoxicity assays and transmission electron microscopy studies.
Diarrhea in Lambs Experimentally Infected with Cryptosporidium Isolated from Calves
Authors: Tzipori S. , Angus K. W. , Gray E. W. , Campbell Iris , Allan Francis
Published: February 2025

Two to 5 days after oral inoculation with Cryptosporidium obtained from infected calves, 7 newborn specific-pathogen-free lambs became depressed and anorectic and developed diarrhea. Four moribund lambs were killed within 3 days after onset of illness, and the 3 other lambs died after protracted intermittent diarrhea and reduced milk intake, which lasted up to 14 days. The small and large intestines were heavily infected with Cryptosporidium, with the terminal portion of the ileum being the most severely affected. Histologic examination revealed villous atrophy, with considerable fusion and epithelial cross-bridging between villi. Lambs infected at 5 to 20 days of age had less severe clinical signs of disease, with intermittent diarrhea, reduced milk intake, and growth retardation. Lambs infected at 30 days of age became infected with the organism, but did not develop clinical signs of disease or growth retardation.
Pharmacokinetics of a Single, Orally Administered Dose of Digoxin in Horses
Authors: Pedersoli W. M. , Ravis W. R. , Belmonte A. A. , McCullers R. M.
Published: February 2025

Digoxin (elixir, 0.022 mg/kg) was administered via stomach tube to healthy horses of mixed breeding and sexes. Serum digoxin concentrations reached a peak (2.21 ± 0.6 ng/ml) at approximately 1 hour after dosing and had a half-life of 28.8 ± 10.7 hours. Digoxin kinetics followed a triexponential curve, indicating that at least a 2 compartmental model is required to characterize the serum concentration-time curve after this route of administration.

It was calculated that to achieve average serum concentrations of 1.1 ng/ml, an oral dose of 17.4 μg of digoxin elixir/kg/day and an iv dose of 6.1 μg of parenteral preparation/kg/day would be required.

There was no significant (P > 0.05) alteration in base-line serum calcium, potassium, and sodium concentrations and heart rate, P-R interval, and mean arterial blood pressure.
Serum Thyroxine and Triiodothyronine Concentrations in Neonatal Foals and Mature Horses
Authors: Chen C. L. , Riley A. M.
Published: February 2025

Serum thyroxine (T-4) and triiodothyronine (T-3) concentrations were assayed in neonatal foals (1.5 to 4 months) and mature horses (2 to 25 years old) by a modified radioimmunoassay procedure. Blood was collected from 52 clinically healthy foals and horses of various breeds (Thoroughbreds, Quarter Horses, American Saddle Horses, and a single cross-bred horse). Neonatal foals had high serum concentrations of T-4 (mean, 4.02 μg/dl) and T-3 (192.9 ng/dl) as compared with the values in mature horses (T-4, mean of 1.76 μg/dl; T-3, mean of 98.69 ng/dl). Stallions had slightly higher T-3; there were no differences between breeds and sexes for serum concentrations of T-4. High serum T-4 and T-3 concentrations in neonatal foals appear to have significant roles in the normal nervous and muscular function and growth in neonatal foals, since hypothyroidism in equine neonates has been reported to show signs similar to those of prematurity in persons, such as neuromuscular incompetence and musculoskeletal dystrophy. Determination of T-4 and T-3 in neonatal foals can be a meaningful screen test for hypothyroidism.
Efficacy of Ivermectin Against Five Genera of Swine Nematodes and the Hog Louse, Haematopinus suis
Authors: Stewart T. B. , Marti O. G. , Hale O. M.
Published: February 2025

Twenty pigs sequentially infected with Oesophagostomum spp, Metastrongylus spp, and Trichuris suis, and maintained on lots contaminated with Ascaris suum and Strongyloides ransomi, were assigned to 1 of 4 groups on the basis of weight, sex, and litter. Each group of pigs was given ivermectin subcutaneously at the rate of 0, 20, 100, or 500 μg/kg of body weight. Lice on pigs were counted before treatment, on posttreatment day 1, and just before necropsy. Pigs were necropsied on posttreatment day 6 or 7, and worms were recovered and counted. Efficacies were: 0% to 100% against A suum; 66% to 100% against S ransomi; 99.4% to 99.9% against Metastrongylus spp; 0% against T suis; 3.2% to 63% against adult Oesophagostomum spp; 61.7% to 87.9% against immature Oesophagostomum spp; and 99% to 100% against Haematopinus suis.
Efficacy of Ivermectin Against the Swine Kidney Worm, Stephanurus dentatus
Authors: Stewart T. B. , Marti O. G. , McCormick W. C.
Published: February 2025

Ivermectin in solution was given subcutaneously (in the neck) at the rate of 0.5 mg/kg of body weight to 5 sows naturally infected with kidney worm (Stephanurus dentatus). Six similar sows were used as nontreated controls. A total of 114 kidney worms were recovered from daily urine samples of 4 of the 5 treated sows (the 5th sow's samples were negative) during the first 4 days after treatment. Ten kidney worms were recovered from daily urine samples of 1 control sow on the 2nd and 3rd days of the posttreatment period. Examination of urine samples from treated sows for kidney worm eggs showed a precipitous numerical decrease. Treated animals became negative between the 5th and 12th days after treatment, and remained negative until necropsy on the 61st day. Compared with control sows, hatchability of eggs and survival of larvae from treated sows was reduced by 9% and 7%, respectively. Kidney worms were not recovered at necropsy from the treated sows, and a total of 392 kidney worms were recovered from the control sows (av 65).
Possible Factors Influencing the Immunoglobulin M Concentration in Swine Colostrum
Authors: Inoue Takeshi
Published: February 2025

The immunoglobulin (Ig) M concentration in swine colostrum was determined by the single radial immunodiffusion method, using 157 samples collected from the same number of farm-raised sows in Yamaguchi Prefecture of Japan during 1976 and 1977. The mean IgM value was 4.16 ± 1.11 mg/ml, and the maximum and minimum values were 7.74 mg/ml and 1.50 mg/ml, respectively.

To elucidate the possible factors influencing the IgM concentration in swine colostrum, the following 12 items were surveyed in the present study: season, district, breed, age, udder section (mamma) from which colostral samples were collected, kind of feed, 4 vaccinations (swine erysipelas live-organism vaccine, hog cholera live-virus vaccine, Japanese encephalitis live-virus vaccine, and transmissible gastroenteritis live-virus vaccine), type of farming, and number of sows raised on a farm. Relationships between the IgM concentration in swine colostrum and each item were analyzed.

Of the 12 items, 3 items—season, breed, and vaccination of swine erysipelas live-organism vaccine—were the most influential on the IgM concentration in colostra of farm-raised sows. Five items—district, age, kind of feed, vaccination with transmissible gastroenteritis live-virus vaccine, and number of sows raised on a farm—were moderately influential. The remaining items—udder section, vaccinations with hog cholera live-virus vaccine and Japanese encephalitis live-virus vaccine, and type of farming—were poorly influential. The multiple correlation coefficient obtained here was 0.5605 (P > 0.05).
Field Evaluation of Enzyme-Linked Immunosorbent Assay for Detection of Antibody to African Swine Fever Virus
Authors: Hamdy F. M. , Colgrove G. S. , de Rodriguez Eva Maria , Snyder M. L. , Stewart W. C.
Published: February 2025

The enzyme-linked immunosorbent assay (elisa) for detection of antibodies to African swine fever virus was evaluated under field conditions in the Dominican Republic. A total of 3,402 swine serums were tested by elisa. All elisa-positive serums (n = 224) and 426 of 2,760 elisa-negative serums were retested by indirect immunofluorescence (iif). There were no antibodies to asf virus detected by iif in elisa-negative serums. By iif, antibodies were detected in only a small portion of the elisa-positive serums. The specificity and sensitivity of elisa and iif were investigated and discussed. It appears that poor quality serums had an effect in elisa results. Detection of immunoglobulin (Ig) G and IgM classes of antibodies in the elisa and iif-positive serums were also performed and related to longevity of African swine fever virus infection. The elisa is recommended as an efficient method in testing large numbers of serums; positive results are to be retested by iif.
Analysis of Postmortem Canine Blood, Cerebrospinal Fluid, and Vitreous Humor
Authors: Schoning Polly , Strafuss A. C.
Published: February 2025

Vitreous humor, blood, and csf collected at antemortem and postmortem examination from 60 dogs were analyzed and compared. Euthanatized dogs were maintained at temperatures of 4 C, 20 C, or 37 C for 3, 6, 12, 24, or 48 hours.

Several postmortem body fluid chemical values remained stable or changed in a consistent matter. They were urea nitrogen (un), glucose, and sodium in vitreous humor; un, carbon dioxide, and sodium in csf; and un, calcium, amylase, total protein, and glucose in blood.
Gastrointestinal Microflora of Calves Fed Fermented Colostrum
Authors: Ward G. E.
Published: February 2025

Viable counts of Escherichia coli, lactobacilli, total anaerobes, total aerobes, and streptococci in the gastrointestinal tract of calves fed fermented colostrum were compared with counts in calves fed whole milk. Counts of all classes of bacteria studied were significantly (P < 0.001) decreased in calves fed fermented colostrum, as compared with counts in calves fed whole milk. Counts of total aerobes, streptococci, and E coli in chyme were similar to those in tissue homogenates, whereas counts of total anaerobes and lactobacilli in chyme were significantly increased (P < 0.001), compared with those in tissue homogenates.
Stability of Viability and Immunizing Potency of Lyophilized, Modified Equine Arteritis Live-Virus Vaccine
Authors: Harry T. O. , McCollum W. H.
Published: February 2025

The Bucyrus strain of equine arteritis virus, previously modified to avirulence and vaccinal virus by 131 serial passages in primary cell cultures of horse kidney followed by 111 passages in primary cell cultures of rabbit kidney, was further passaged in cultures of the E. Derm (NBL-6) cell line, a continuous diploid cell line. Pools of the 16th and 25th passages of the virus in this last equine dermal cell line were lyophilized and stored in lots at 37 C, 23 to 28 C, 4 C, and −20 C. The viability of the vaccinal virus deteriorated rapidly during storage at 37 C and at 23 to 28 C, but was relatively stable at 4 C and at −20 C for at least 1 year.

The vaccine stored at 4 C for 9 months protected 2 horses, subsequently inoculated with avirulent virus, from arteritis, whereas the 2 nonvaccinated control horses inoculated simultaneously developed severe signs of the disease and died of acute arteritis.
Esophageal Healing in the Pony: Comparison of Sutured vs Nonsutured Esophagotomy
Authors: Stick John A. , Krehbiel Janver D. , Kunze Dolores J. , Wortman Jeffrey A.
Published: February 2025

Esophageal healing was evaluated in 10 ponies after sutured and nonsutured cervical esophagotomy techniques.

Mucosal healing occurred significantly (P < 0.005) faster after sutured esophagotomies (x = 7.5 days after surgery) than after nonsutured esophagotomies (x = 25.6 days after surgery), based on endoscopic and clinical evaluations. Although endoscopy was an accurate assessment of the return of normal passage of a food bolus through the esophagus, 4 of 10 ponies had radiographic evidence of a sinus tract after the mucosa was considered healed, based on endoscopic and clinical examinations. The surgical skin wound also healed significantly sooner after sutured esophagotomies (x = 10 days) than after nonsutured esophagotomies (x = 33.4 days).

A traction diverticulum developed in all ponies with nonsutured esophagotomies, but occurred in only 1 pony with sutured esophagotomy. Minor complications were seen more frequently with sutured esophagotomy than with a nonsutured esophagotomy, but were resolved with local therapy. Saliva appeared to inhibit wound healing.

All ponies were fed through esophagostomy tubes until the mucosa at the esophagotomy site was considered healed. Except for 1 sutured esophagotomy that dehisced, sutured esophagotomy was superior to nonsutured esophagotomy, because earlier establishment of a mucosal seal resulted in more rapid healing and reduced nursing care.
Effects of in Vitro Hemolysis on Equine Serum Chemical Values
Authors: Dorner J. L. , Hoffmann W. E. , Lock T. F.
Published: February 2025

Quantitative, as well as qualitative, serum chemical values were determined in 13 healthy horses after the addition of 22 mg, 54 mg, 92 mg, and 194 mg of hemoglobin/dl to each animal’s unadulterated serum. Sixteen chemical procedures were considered and significant changes (P < 0.001) in serum creatinine, alanine aminotransferase, sodium, and total bilirubin were observed after the addition of 194 mg of hemoglobin/dl. Quantitative changes most markedly affected the aforementioned chemical values, with lesser effects on phosphorus and potassium.
Effects of Ergocryptine on Plasma Prolactin, Luteinizing Hormone, and Progesterone in the Periparturient Sow
Authors: Whitacre M. D. , Threlfall W. R.
Published: February 2025

Effects of ergocryptine (erg) on the periparturient sow were assessed by measuring changes in prolactin, luteinizing hormone, and progesterone in plasma. Hormones in plasma were determined on samples collected daily from 21 days before parturition until postpartum day (ppd) 21. Administration of erg completely blocked the initiation of lactation and prevented the surge in prolactin that occurred just before parturition, as compared with effects in control sows. The gestation period was shorter (P < 0.01) in erg-treated sows compared with the gestation period in controls. Although the number of pigs farrowed was not different between treated and control sows, the erg-treated sows did not raise any pigs to ppd 21. Luteinizing hormone concentrations were higher (P < 0.01) from 10 days before parturition until ppd 21, but plasma progesterone concentrations were not different in treated sows when compared with concentrations in control sows.
Long-Term Study of the Ocular Effects of Orthovoltage Irradiation in Rats
Authors: Peiffer Robert L. , Wright Walter , Steinbok Paul , Mahaley M. Stephen
Published: February 2025

In groups of young rats subjected to 2,000, 3,000, 4,000, and 6,000 rads of orthoradiation, associated ocular pathologic changes were assessed by clinical examination at 30 and 120 days and by light microscopy at 96 to 240 days after irradiation. Significant observations were limited to the lens. Dose and temporal related alterations included a spectrum of cataractous changes from vacuolation to mature cataracts.
Displacement of Protein-Bound Thiopental by Sodium Methiodal May Contribute to Anesthetic Complications During Canine Myelography
Authors: Bonhaus Douglas W. , Sawyer Donald C. , Hook Jerry B.
Published: February 2025

Sodium methiodal is a contrast medium commonly used during subarachnoid myelography. Clinically occurring concentrations of sodium methiodal displaced bound thiopental from brain homogenate and serum in vitro. These results indicate that some anesthetic complications during canine myelography may be due to displacement of bound thiopental.
Pharmacokinetics of Naproxen in the Dog
Authors: Frey H. H. , Rieh Bettina
Published: February 2025

The pharmacokinetics of naproxen was studied in mongrel dogs. After iv injection of a 5 mg/kg dose, plasma concentrations decreased biexponentially, with an average elimination half-life of 74 hours. The drug was highly protein-bound (> 99%) and had a correspondingly low apparent volume of distribution (0.13 L/kg). After naproxen was given orally, absorption was rapid, and the bioavailability ranged between 68% and 100%. With an initial dose of 5 mg/kg given orally, therapeutic plasma concentrations could be maintained by giving 1 daily dose of 1.2 to 2.8 mg/kg.
Effects of Storage on Concentration of Hydrocortisone (Cortisol) in Canine Serum and Plasma
Authors: Olson Patricia N. , Bowen Richard A. , Husted Paul W. , Nett Terry M.
Published: February 2025

A specific radioimmunoassay was used to measure concentrations of hydrocortisone (cortisol) in the serum and plasma of 4 dogs. Differences (P > 0.05) in concentrations of cortisol were not found between serum and plasma (from EDTA-treated and heparinized blood samples). Differences (P > 0.05) in serum or plasma concentrations of cortisol were not found between samples stored at 4 C for various times (10 minutes, 10 hours, 40 hours) after collection, but before removal of rbc.

In a study designed to determine the stability of cortisol in serum samples stored at room temperature, degradation was dependent on the initial serum concentrations of cortisol. Decreases (P > 0.05) did not occur in concentrations of cortisol in serum samples stored up to 15 days when initial concentrations of cortisol were less than 15 ng/ml. However, when initial concentrations of cortisol were approximately 55 ng/ml and 80 ng/ml, significant (P > 0.05) degradation occurred after 9 and 5 days of storage, respectively.

Results of this investigation indicate that either serum or plasma of dogs is suitable for radioimmunoassay of cortisol and that samples (with and without added coagulants) incubated at 4 C may be left uncentrifuged for up to 40 hours without cortisol degradation. However, prolonged storage of serum at room temperature is detrimental, particularly for samples having large concentrations of cortisol.
Pharmacokinetics of Gentamicin in the Juvenile Dog
Authors: Riviere J. Edmond , Coppoc Gordon L.
Published: February 2025

The pharmacokinetics of gentamicin and/or creatinine clearances were investigated in eleven 5-month-old Beagles. A 2-compartment open model was used to describe the drug’s disposition, as judged by error sums of squares and residual plot analyses. Half-life (elimination phase) was 60.9 ± 7.8 minutes (mean ± sd), the volume of distribution calculated from the area under the curve was 35.4 ± 3.6 L/100 kg of body weight, and the clearance of the drug from the body was 4.08 ± 0.62 ml/min/kg of body weight. The 24-hour creatinine renal clearance in these dogs was 3.82 ± 0.92 ml/min/kg, consistent with gentamicin being eliminated mainly by glomerular filtration. Other pharmacokinetic values were also determined.
Erythrocyte Protoporphyrin in Experimental Chronic Lead Poisoning in Calves
Authors: George Jeanne Wright , Duncan J. Robert
Published: February 2025

Erythrocyte protoporphyrin was measured in calves by the free erythrocyte porphyrin (fep) test. The fep of 15 healthy calves was 142.8 ± 32.4 μg/dl (mean ± sd) of packed erythrocytes or 45.6 ± 10.3 μg/dl of whole blood. Biweekly oral lead administration to 3 calves produced a continuous increase of fep to between 2,800 and 6,033 μg/dl of packed erythrocytes after 20 weeks. Fluorescence scans of diluted blood were used to demonstrate that erythrocyte protoporphyrin from lead-poisoned calves was present as an approximately 2:1 mixture of zinc protoporphyrin and free protoporphyrin. Blood lead concentration increased in calves after lead was given (orally), but had greater weekly fluctuations than fep. Mild anemia developed in 2 of 3 animals late in the experiment. Basophilic stippling of erythrocytes occurred in 1 calf.
Behavioral and Cardiorespiratory Responses to 4-Aminopyridine in Healthy Awake Horses
Authors: Klein Lin , Hopkins Judy
Published: February 2025

4-Aminopyridine was administered in incremental iv doses to healthy horses to evaluate cardiorespiratory and behavioral effects. Doses of 100 μg/kg produced apparent sensory discomfort, manifested by wiggling or curling of the lips and tongue, arching or stretching the neck, snorting, squealing, and coughing. At cumulative dosages of 300 to 500 μg/kg, muscle tremors, a stilted gait, and signs of excitement occurred. Once signs of excitement occurred, additional administration of 4-aminopyridine resulted in prolonged excitement consisting of severe muscle tremors and exaggerated responses to external stimuli. Heavy sedation with xylazine provided nearly complete relief from these effects. 4-Aminopyridine could be a useful adjunct to treatment of botulism in horses; however, administration of doses in excess of 300 to 500 μg/kg may cause severe cns excitatory effects.
Viral Antibody Studies of Laboratory Dogs with Diarrheal Disease
Authors: Binn L. N. , Marchwicki Ruth H. , Eckermann E. H. , Fritz T. E.
Published: February 2025

Viral antibody studies were done on laboratory dogs in an epizootic of gastrointestinal disease. Increased hemagglutination-inhibition antibody titers to a parvovirus (pv) antigenically related to feline panleukopenia virus were found in convalescent serum specimens of 78% (20/26) of the affected dogs and in 83% (5/6) of apparently healthy dogs. With one exception, all dogs tested had significant levels of hemagglutination-inhibition antibody to this pv. Similar increased antibody titers were found to feline panleukopenia virus. Also, neutralizing antibody responses were detected to the canine coronavirus in 24% (6/25) and canine herpesvirus in 45% (10/22) of the affected dogs. However, antibody titers did not increase to canine distemper virus, infectious canine hepatitis virus, canine parainfluenza virus, or minute virus of canines.

Subsequent serotesting of the colony provided evidence that additional pv infections occurred in pups from each of 8 litters born 3 to 8 months after the epizootic. These findings indicated the continued presence of the pv for more than 1 year in the infected colony.

Of 19 laboratory personnel who worked with the affected dogs, none, including 4 with a concurrent diarrheal disease, developed or had antibodies to the pv or canine coronavirus.
Effects of an Anticholinergic and a Corticosteroid on Acute Pancreatitis in Experimental Dogs
Authors: Attix Edward , Strombeck Donald R. , Wheeldon Eric B. , Stern Judith S.
Published: February 2025

In a model developed to study acute pancreatitis in the dog, the disease process was comparable with the spontaneously occurring disease. Infusion of oleic acid into the accessory pancreatic duct induced, grossly and microscopically, acute hemorrhagic pancreatitis with pancreatic atrophy, fibrosis, fat necrosis, and edema. Clinical changes included persistent fever and tachycardia in all dogs and abdominal pain, vomiting, and diarrhea in most. Serum amylase and lipase activities increased markedly as did activities of alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase. Hematologic alterations included hemoconcentration (despite intensive fluid therapy) and leukocytosis due primarily to neutrophilia and monocytosis. Neither corticosteroid nor anticholinergic therapy begun 24 to 32 hours after oleic acid infusion altered the course of the disease. Dogs survived 8 days and appeared clinically normal when the study was terminated.
Inheritance of Primary Glaucoma in the Beagle
Authors: Gelatt Kirk N. , Gum Glenwood G.
Published: February 2025

Primary glaucoma in the Beagle is inherited as an autosomal recessive trait. Twenty-six matings of affected × affected Beagles resulted in 77 offspring with glaucoma (38 males/39 females). Four matings of glaucomatous Beagles (1 male/3 females) × normal laboratory-quality Beagles (3 males/1 female) yielded 15 ocular normotensive Beagles (6 males/9 females). Three matings of glaucomatous Beagles (3 males/1 female) × carrier Beagles (1 male/2 females) produced 19 offspring; 8 exhibited glaucoma (2 males/6 females) and 11 were ocular normotensive (6 males/5 females).
Canine Infectious Tracheobronchitis: Effects of an Intranasal Live Canine Parainfluenza-Bordetella bronchiseptica Vaccine on Viral Shedding and Clinical Tracheobronchitis (Kennel Cough)
Authors: Kontor E. J. , Wegrzyn R. J. , Goodnow R. A.
Published: February 2025

A modified-live intranasal (in) canine parainfluenza (cpi)-virus Bordetella bronchiseptica vaccine was evaluated in dogs for efficacy against laboratory-induced canine infectious tracheobronchitis. The comparative efficacies of in and parenteral administrations of the cpi virus fraction were also evaluated. The frequency and duration of clinical tracheobronchitis, blood serum agglutination titer, humoral antibody response, and duration of cpi virus and B bronchiseptica shedding were measured.

Group A dogs were vaccinated subcutaneously or im with an experimental cpi vaccine and challenge exposed with cpi virus. Group B dogs were vaccinated in with avirulent cpi virus-B bronchiseptica live antigens and challenge exposed with virulent cpi virus and virulent B bronchiseptica. The in vaccination (group B) significantly reduced (P ≤ 0.001) the occurrence of clinical tracheobronchitis by 96%. The combined challenge exposure of virulent cpi and virulent B bronchiseptica produced a synergistic enhancement of the clinical signs of kennel cough.

The percentage of days after challenge exposure that virus shedding was detected for controls equaled 70% as compared with 50% and only 1% for parenterally and in vaccinated dogs, respectively. Isolation of virulent B bronchiseptica microorganisms was reduced 89% in dogs vaccinated in compared with controls. The geometric mean humoral antibody titers to cpi virus after 2 parenteral vaccinations and 1 in vaccination were 1:43 and 1:34, respectively.
Relationship of Selected Clinical Renal Function Tests to Glomerular Filtration Rate and Renal Blood Flow in Cats
Authors: Ross Linda Anne , Finco Delmar R.
Published: February 2025

SUMMARY AND CONCLUSIONS

Results of 3 clinical tests of renal function—urine concentrating ability and disappearance of plasma phenosulfonphthalein (psp) and sodium sulfanilate (ss) were compared with those of 2 classic tests, glomerular filtration rate (gfr) and renal blood flow (rbf), in 11 cats before and after reduction of renal mass. Values (mean ± sd) obtained from normal cats were maximum urine concentration of 2,270 ± 407 mOsm/kg (specific gravity values of 1.067 ± 0.015); T½ for plasma disappearance of psp of 24.27 ± 3.5 minutes; Tν for plasma disappearance of ss of 44.42 ± 5.67 minutes; gfr of 2.94 ± 0.32 ml/min/kg; and rbf of 10.61 ± 1.71 ml/min/kg. After reduction of renal mass by vascular ligation and nephrectomy, the cats became azotemic and had significant decreases in gfr and rbf (P < 0.005), but still were able to concentrate urine to a considerable extent. Both maximum urine concentration and psp plasma decay were poorly correlated with gfr (r = 0.4060 and 0.3694, respectively) and rbf (r = -0.3439 and -0.3427). Sulfanilate half-life had better correlation with gfr (r = –0.7004) than with rbf (r = –0.5716). Both gfr and rbf increased significantly (P < 0.005) between postsurgical weeks 1 and 9.

It was concluded that experimental cats with azotemia retain considerable ability to concentrate urine and that the ss test is superior to both the psp test and urine concentretion test for clinical estimation of renal function.
Effects of Clinical and Subclinical Gastrointestinal Helminthiasis on Digestion and Energy Metabolism in Calves
Authors: Randall R. W. , Gibbs H. C.
Published: February 2025

Digestion and energy metabolism trials were conducted in 2 groups of 4 steer calves each, experimentally infected with Codperia and Ostertagia larvae. In group 1 calves given an amount expected to cause clinical parasitism (8,000 larvae/kg0.75), feed intake and nutrient digestibility were significantly (P < 0.05) depressed at postinfection week (piw) 3 (the time that infections became patent); nitrogen balance in these calves was also low. The apparent absorbed nitrogen fraction was significantly (P < 0.05) depressed because of a significant (P < 0.05) decrease in digestion. Protein catabolism was also increased. Although energy balance was significantly depressed at piw 3, the calves seemed to recover from the effects of parasitism by piw 5. In group 1 calves, weight gains were significantly (P < 0.05) depressed, with mean weight gains of 10.68 kg of body weight as compared with gains of 41.44 kg for group 3 calves (noninfected controls).

In group 2 calves given an amount expected to cause a subclinical infection (800 larvae/kg0.75), nitrogen absorption was significantly (P < 0.05) depressed at piw 2 and 3 and energy balance was significantly (P < 0.05) depressed at piw 3. In group 2 calves, mean weight gains (34.76 kg) were less than were those for group 3 calves (41.44 kg).

The degree of parasitism seen in group 2 calves was comparable with that observed in field examinations of naturally infected calves of approximately the same age. Seemingly, under grazing conditions in Maine, these low levels of parasitism could result in appreciable production losses in young animals.
Enzyme-Linked Immunosorbent Assay for the Quantitation of Immunoglobulin G Bound to Escherichia coli
Authors: Mueller R. , Carroll E. J.
Published: February 2025

Two strains of Escherichia coli were opsonized by incubation in heat-inactivated bovine blood serum and in whey. The opsonized bacteria were then immobilized by complexing with anti-bovine antibodies previously coated to walls of polystyrene tubes. The amount of bovine immunoglobulin (Ig) G in the immobilized complex was then determined by a direct enzyme-linked immunosorbent assay, using peroxidase as enzyme. Thus, a direct measurement of one class of opsonic substances on the surface of the organisms was determined. The sensitivity for measurement of IgG ranged from nanograms to micrograms. After incubation in blood serum, 500-fold more IgG was found on the surface of the serum-sensitive E coli strain than on the surface of the serum-resistant strain. The amount of IgG absorbed from whey in each instance was much less than that absorbed from serum. The number of bound molecules per bacterium ranged between 2,000 and 2,000,000, depending on both the strain and the serum.
Phenylbutazone Toxicosis in Equidae: A Biochemical and Pathophysiologic Study
Authors: Snow D. H. , Douglas T. A. , Thompson H. , Parkins J. J. , Holmes P. H.
Published: February 2025

Toxic effects of phenylbutazone (pbz) in ponies and horses were studied, using a variety of biochemical, pathophysiologic, and pathologic methods. At dosage levels of 10 to 12 mg/kg of body weight/day for 8 to 10 days, ponies frequently developed clinical signs of toxicosis characterized by hypoproteinemia. Studies using 51CrCl3 demonstrated that pbz caused a protein-losing gastroenteropathy. The plasma loss was usually associated with gastrointestinal ulceration, but sometimes occurred without obvious lesions in mildly affected animals. Similar studies (8.2 mg/kg/day for 13 days) in Thoroughbreds indicated that they were less susceptible to pbz toxicity; however, a degree of hypoproteinemia occurred in 4 of 6 treated Thoroughbreds.
Resistance of Pasteurella multocida to Rabbit Neutrophil Phagocytosis and Killing
Authors: Rush Howard G. , Glorioso Joseph C. , DaRif Craig A. , Olson Leonard C.
Published: February 2025

The susceptibilities of several Pasteurella multocida strains to serum bactericidins and to killing by rabbit polymorphonuclear neutrophils (pmn) were investigated, using in vitro assays. Strain Bunia II (serotype 5,12:E) was killed by both immune and normal rabbit sera containing active complement, and strains R1 (serotype 3,12:A) and 656 (serotype 12:B) were serum resistant. Strain R1 opsonized with immune or normal rabbit serum with complement or with immune antibody alone was phagocytized by neutrophils, and strain 656 was ingested only after opsonization with immune antibody in the presence or absence of complement. Complement alone was ineffective as an opsonin for the last 2 serotypes. Neither isolate was resistant to pmn killing. Growth of strain R1 in subcutaneously implanted chambers in rabbits did not increase the resistance of this organism to pmn. Comparison of phagocytosis and killing of this isolate with 2 virulent rabbit strains of P multocida—strains L-A (serotype 12:A) and 7228 (serotype 14:D)— demonstrated that strain L-A was resistant to destruction by neutrophils, whereas strains 7228 and R1 were killed. Resistance of strain L-A was not associated with the hyaluronic acid capsule.
Evaluation of Electronic Tonometers in the Rabbit Eye
Authors: Gelatt Kirk N. , Gum Glenwood G.
Published: February 2025

The MacKay-Marg, pneumatonograph, and EMT-20 tonometers were evaluated in the normal rabbit eye. Tonometric scale readings were compared with the manometric recordings from the anterior chamber. Tonometry was performed with the manometric system closed and open to the reservoir column. The MacKay-Marg tonometer evaluated in the closed and the open manometric systems was highly reliable (goodness of fit (r2) = 0.958 and 0.961, respectively) with intraocular pressures (iop) up to 50 mm of Hg and similarly (r2 = 0.949 and 0.967, respectively) with iop up to 100 mm of Hg. The pneumtiatongraph also exhibited high reliability, r2 = 0.936 (closed) and 0.898 (open), at pressures up to 50 mm of Hg and r2 = 0.932 (closed) and 0.948 (open) at iop up to 100 mm of Hg. The EMT-20 tonometer was least satisfactory for the normal rabbit eye, with r2 ranging from 0.069 to 0.171.
Infestivity of Psoroptes cuniculi in Rabbits
Authors: Arlian Larry G. , Kaiser Steven , Estes Stephen A. , Kummel Barbara
Published: February 2025

Starving Psoroptes cuniculi were found to survive off the host for 4 to 21 days at relative humidities between 20% and 99% and temperatures between 5 and 30 C. Within these extremes, survival was greatest at low temperature and high relative humidity (rh). Mites were infestive for at least 50% of their survival times and may have infested new hosts in contaminated facilities. A temperature of 40 C and 20% rh maintained for 24 hours caused 100% mortality in test mites. Other selected combinations of temperature above 40 C and rh ≤ 75% also caused 100% mortality in 2 days or less. These conditions could be used to control these mites in vacated contaminated premises.
Retinal Atrophy in a Swiss Hound
Authors: Bergsjø T. , Olsen E. , Goebel H. , Koppang N. , Nilsson S. E. G. , Armstrong D.
Published: February 2025

A new retinal dystrophy is reported in an 8-year-old Swiss hound. This abiotrophy demonstrated a profuse leakage of fluorescein dye, extinguished electroretinogram (a, b, c-wave), and standing potential of the eye.

Photoreceptor outer segments were destroyed; retinal pigment epithelial cells showed regional defects, while the remaining cells were frequently devoid of apical villi and basal infoldings. Migrating pigment-bearing cells were present in the markedly thin, gliotic retina, but synaptic contacts were still apparent.
Urine Concentrations of Gentamicin, Tobramycin, Amikacin, and Kanamycin After Subcutaneous Administration to Healthy Adult Dogs
Authors: Ling Gerald V. , Conzelman Gaylord M. , Franti Charles E. , Ruby Annette L.
Published: February 2025

Gentamicin, tobramycin, amikacin, and kanamycin were given subcutaneously in separate trials to healthy adult dogs of both sexes. Daily dosage levels were as follows: gentamicin, 6.6 mg/kg of body weight; tobramycin, 3 mg/kg; amikacin, 15 mg/kg; and kanamycin, 11 mg/kg. Gentamicin, tobramycin, and amikacin were given in divided doses at 8-hour intervals for 5 consecutive 8-hour periods, whereas kanamycin was given in divided doses at 12-hour intervals for 4 consecutive 12-hour periods.

Mean 8-hour urine concentrations ± 1 sd were gentamicin, 107 ± 33 μg/ml; tobramycin, 66 ± 39 μg/ml; and amikacin, 342 ± 153 μg/ml. Mean urine concentrations (± 1 sd) for kanamycin were 473 ± 306 μg/ml in urine collected between 0 and 6 hours after dosing and 63 ± 47 μg/ml in urine collected 6 to 12 hours after dosing.