bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of efrotomycin in feed on the quantity, duration, and prevalence of shedding and antibacterial susceptibility of Salmonella typhimurium in experimentally infected swine
Authors: Jacks Thomas M. , Frazier Easter , Judith Fredric R. , Olson George
Published: February 2025

The influence of efrotomycin administered at the rate of 16 mg/kg of feed in 10 Salmonella typhimurium-inoculated pigs was determined by comparing this group with a group of 10 pigs inoculated with S typhimurium that were given nonmedicated feed. Two control groups of 4 noninoculated pigs each, 1 group medicated with efrotomycin at 16 mg/kg of feed, the other nonmedicated, also were evaluated.

An inoculum of 1.7 × 1010 colony-forming-units/pig induced colonization of S typhimurium in all 20 pigs. Evaluation of the quantity of shedding did not reveal a clear or consistent treatment-related increase in S typhimurium counts; mean differences between the nonmedicated and medicated groups never exceeded 1 log unit. On the last day of the study (day 56 of the medication), 8 nonmedicated and 9 medicated pigs were determined to be infected with S typhimurium via enrichment procedures, so there was no difference in duration of shedding, and there were no significant differences in prevalence of shedding between the nonmedicated and medicated groups at any of the sampling times. Of 1,340 S typhimurium colonies isolated from the nonmedicated and medicated groups, 1,330 were susceptible to all 12 antibacterials tested, indicating no treatment-related effect on susceptibility. At necropsy, S typhimurium was not isolated from any liver or spleen specimens, and was isolated from only 2 of 20 lymph nodes. However, S typhimurium was isolated via enrichment from the cecal contents from all 20 pigs. There were no treatment-related differences in feed consumption, weight gain, or feed efficiency.

Appreciable differences in the measurements were not found between the efrotomycin-medicated and nonmedicated pigs.
Evaluation of a combination of xylazine, ketamine, and halothane for anesthesia in llamas
Authors: Gavier Dolores , Kittleson Mark D. , Fowler Murray E. , Johnson Lynne E. , Hall George , Nearenberg Deborah
Published: February 2025

Anesthesia induced by use of a combination of xylazine, ketamine, and halothane, under conditions of spontaneous and mechanically controlled ventilation, was evaluated in 5 llamas positioned in dorsal recumbency. Using chronically implanted catheters, systemic arterial blood pressure, pulmonary arterial pressure, right atrial pressure, heart rate and rhythm, cardiac output, blood pH and gas tensions, body temperature, and respiratory rate were measured before anesthesia induction (baseline), throughout the anesthetic period, and for 1 hour into the recovery period. During anesthesia, llamas undergoing spontaneous ventilation developed hypercapnia and respiratory acidosis. Cardiovascular function was decreased during both types of ventilation. The combination of xylazine, ketamine, and halothane in various doses and 2 ventilation procedures (spontaneous and controlled) provided a reliable method for general anesthesia in llamas, but marked cardiovascular depression developed during anesthesia maintenance with halothane. Spontaneous ventilation resulted in potentially clinically important respiratory acidosis.
Evaluation of renal gentamicin depletion kinetic properties in sheep, using serial percutaneous biopsies
Authors: Brown S. Anthony , Baird A. N.
Published: February 2025

Tissue drug residue research often involves the killing of an animal every time tissue concentrations are determined. To decrease the number of animals required to perform tissue depletion studies and to circumvent the statistical problems associated with determining tissue depletion kinetic properties, using multiple animals, the renal depletion profile of gentamicin from individual sheep was studied, using a bilateral renal translocation technique. Seven ewes were surgically altered, allowed to stabilize, and then allocated into 2 groups; group-1 sheep (n = 4) were given 3 mg of gentamicin/kg, im, q 12 h for 10 days, and group-2 sheep (n = 3) were not given gentamicin. The kidneys from all ewes were biopsied 9 times over 74 days after the termination of gentamicin treatment. The renal concentrations of gentamicin were measured by use of a validated tissue digestion procedure coupled with a liquid-phase fluorescence polarization immunoassay. On days 75 and 77 after the end of gentamicin treatment, all ewes were euthanatized and necropsied. The concentrations of gentamicin in the biopsy specimens ranged from 71.9 to 183 μg/g on days 1 and 2 after dosing, and decreased to concentrations ranging from 3.99 to 7.35 μg/g on days 73 and 74 after the end of dosing. The decrease in renal gentamicin concentrations was best described by a biexponential equation. The early phase half-life was 2.8 days, whereas the terminal phase half-life was 59 days (harmonic means). There was no difference in the appearance or histologic features of the kidneys from groups 1 and 2. The only lesions noticed were linear fibroses that were attributed to the biopsy procedure.
Peanut agglutinin as a surface marker for canine T lymphocytes
Authors: Turnwald Grant H. , McClure Jill J. , Powell Mary D. , Shao Kung-Ping P.
Published: February 2025

Peanut agglutinin (pna) and surface immunoglobulin (SIg) were investigated as markers for T and B lymphocytes in blood and lymphoid tissues of dogs of various ages. In the blood study, 4 age groups (n = 8 dogs/group) were used. The mean (± sd) percentages of pna-positive (pna+) cells were 68.4 ± 8.6% (group 1, < 1 year old), 70.3 ± 9.2% (group 2, 1 to 2 years old), 72.0 ± 3.7% (group 3, 5 to 6 years old), and 63.8 ± 10.1% (group 4, 10 to 11 years old). The mean percentages of SIg-positive (SIg+) cells in blood were 32.1 ± 10.6% (group 1), 43.2 ± 7.0% (group 2), 34.3 ± 4.8% (group 3), and 35.0 ± 6.8% (group 4). The mean total percentages of pna+ and SIg+ cells were 100 ± 6.0% (group 1), 113.5 ± 4.9% (group 2), 106.3 ± 5.3% (group 3), and 98.9 ± 9.2% (group 4). The proportions of pna+ and SIg+ cells in dogs of group 2 were significantly (P < 0.05) different from those in dogs of the other groups.

Serial changes in pna+ and SIg+ cells were investigated in blood of 6- to 29-week-old pups (n = 8). A significant (P < 0.05) transient decrease in pna+ cells and a corresponding increase in SIg+ cells was observed in pups between 14 and 17 weeks old.

Lymphoid tissue specimens and blood samples were obtained from 2- to 6-month-old dogs (n = 11) and from 6-to 12-month-old dogs (n = 10). Percentages reflected the combined data from both groups because there were no significant differences between the 2 age groups. The mean percentages of pna+ cells were: blood, 68.4 ± 8.6%; thymus, 86.6 ± 16.3%; spleen, 29.5 ± 16.0%; lymph node, 48.5 ± 16.0%; and bone marrow, 30.8 ± 26.4%. The mean percentage of SIg + cells were: blood, 32.1 ± 10.6%; thymus, 3.1 ± 5.5%; spleen, 69.3 ± 10.3%; lymph node, 55.4 ± 15.2%; and bone marrow, 65.4 ± 22.4%.

The procedure to identify T lymphocytes in blood and lymphoid tissue was easy to perform, was reproducible, and could be performed on as few as 106 cells. Percentages of T lymphocytes identified compared favorably with those of other studies.
Susceptibility of cats to infection with Ehrlichia risticii, causative agent of equine monocytic ehrlichiosis
Authors: Dawson Jacqueline E. , Abeygunawardena Indra , Holland Cynthia J. , Buese Margaret M. , Ristic Miodrag
Published: February 2025

Eight adult cats were inoculated iv (n = 6) or sc (n = 2) with Ehrlichia risticii-infected P388D1 (continuous murine macrophage) cells or with E risticii released from P388D1 cells. Three additional cats were inoculated with organism-free P388D1 cultured monocytes, and 1 cat, which served as a medium control, was inoculated with balanced salt solution. Clinical signs of illness were observed in the iv inoculated cats from which E risticii was isolated. One cat developed intermittent diarrhea between postinoculation days (pid) 8 and 18, and the other cat developed lymphadenopathy, acute depression, and anorexia between pid 20 and 24. Ehrlichia risticii was isolated in cultures from 2 of 6 iv inoculated cats on pid 6, 10, and 17. Both cats were inoculated with E risticii released from the P388D1 cells. Ehrlichia risticii was not isolated from sc inoculated cats or from control cats. All 8 cats inoculated with E risticii seroconverted between pid 10 and 23.

A pony inoculated with E risticii isolated from 1 of the inoculated cats developed clinical signs of equine monocytic ehrlichiosis including fever, anorexia, depression, and mild colic. Ehrlichia risticii was isolated from the blood of this pony on pid 7, 9, 11, and 16.
Morphologic and morphometric studies of the vagus and recurrent laryngeal nerves in clinically normal adult dogs
Authors: Braund Kyle G. , Steiss Janet E. , Marshall Arvle E. , Mehta Jagjivan R. , Toivio-Kinnucan Maria , Amling Karen A.
Published: February 2025

Morphologic and morphometric studies were performed on the vagus nerve and its major branch, the recurrent laryngeal nerve (rln): (1) to determine normal histologic data in myelinated fibers of clinically normal young adult dogs, (2) to establish reference values for mean fiber diameter in the vagus nerve and in the proximal and distal portions of the rln, and (3) to delineate relative frequency distribution curves for each nerve. Few degenerative changes were observed in single teased-nerve fiber preparations. There was no statistical difference between left and right sides of the vagus nerve or between the proximal and distal portions of the rln (right and left sides). In contrast to the unimodal distribution of fibers in the vagus nerve and the proximal portion of the rln, the distribution of fibers in the distal portion of the rln was bimodal. Mean (± sd) fiber diameters of the vagus nerve and in the proximal portion of the rln (3.02 ± 1.44 μm and 3.63 ± 1.49 μm, respectively) were not significantly different, despite a shift to large-diameter fibers in the latter. However, mean fiber diameters of distal and proximal portions of the rln (5.56 ± 1.88 μm and 3.63 ± 1.49 μm, respectively) were significantly (P < 0.001) different. Approximately 86% of fibers in the vagus nerve and 76% of fibers in the proximal portion of the rln, had a diameter < 5 μm, and about 70% of fibers in the distal portion of the rln had a diameter > 5 μm. The fiber diameter in the distal portion of the rln ranged from 2 μm to 10 or 11 μm, yielding a computed conduction velocity of 54 to 60 m/s.
Comparison of three techniques to detect Leptospira interrogans serovar hardjo type hardjo-bovis in bovine urine
Authors: Bolin Carole A. , Zuerner Richard L. , Trueba Gabriel
Published: February 2025

Nucleic acid hybridization, bacteriologic culture, and a fluorescent antibody test were compared for detection of Leptospira interrogans serovar hardjo type hardjo-bovis in bovine urine. Seventy-five urine samples were collected from pregnant cows challenge exposed with type hardjo-bovis. Twenty samples were collected from steers not exposed to hardjo-bovis. Sediments from each sample were examined, using fluorescent antibodies and a repetitive sequence element nucleic acid probe, to detect the presence of leptospires. Urine samples were processed for bacteriologic culture, using standard techniques. Under laboratory conditions typically used for these techniques, leptospires were detected in 60 of 75 urine samples from challenge exposed cows by nucleic acid hybridization, in 24 samples by fluorescent antibody test, and in 13 samples by bacteriologic culture. Leptospires were not detected in the urine of steers not exposed to hardjo-bovis.
Hemagglutination and hemagglutination inhibition of turkey red blood cells with Mycoplasma hyopneumoniae
Authors: Young Theresa F. , Erickson Barbara Z. , Ross Richard F. , Wannemuehler Yvonne
Published: February 2025

The ability of Mycoplasma hyopneumoniae to agglutinate rbc was evaluated to develop an in vitro cytadsorption assay. Using swine rbc in a microtitration hemagglutination test, no agglutination or partial agglutination was detected. Comparison of rbc from various other species indicated that improved hemagglutination was obtained with rbc from turkeys. This hemagglutination was detected only when mycoplasma cells used in the assay had been frozen and thawed, heated at 50 C for 30 minutes, or treated with trypsin. Treatment of rbc with trypsin or neuraminidase enhanced hemagglutination. Possible surface lectin activity in M hyopneumoniae was evaluated by use of carbohydrates in a blocking assay; hemagglutination was not inhibited by any of 13 carbohydrates evaluated. Mycoplasma hyopneumoniae convalescent porcine serum and monoclonal antibodies against 2 M hyopneumoniae immunogens of molecular weights of 64,000 and 41,000 inhibited hemagglutination.
Dose titration and confirmation tests for determination of cesticidal efficacy of epsiprantel in dogs
Authors: Corwin R. M. , Green S. P. , Keefe T. J.
Published: February 2025

Fifty-five dogs, naturally infected with Taenia sp or Dipylidium caninum or both, were assigned to the following treatment groups for dose titration studies with epsiprantel: nonmedicated control dogs (n = 14), medicated dogs given a dosage of 2.75 mg/kg of body weight (n = 15), medicated dogs given a dosage of 5.5 mg/kg (n = 16), and medicated dogs given a dosage of 8.25 mg/kg (n = 10). Medication was given orally in a tablet formulation. Feces were examined for cestodes passed and the gastrointestinal tract was examined at necropsy for retained cestodes. Efficacy of epsiprantel was 92.9% against Taenia and 44.8% against Dipylidium for a dosage of 2.75 mg/kg, 100% against Taenia and 99.8% against Dipylidium for a dosage of 5.5 mg/kg, and 94.6% against Taenia and 100% against Dipylidium for a dosage of 8.25 mg/kg.

For dose confirmation, 36 dogs naturally infected with Taenia sp or D caninum or both were allotted to 2 treatment groups: nonmedicated control dogs (n = 16) and dogs medicated with epsiprantel at a dosage of 5.5 mg/kg (n = 20). Efficacy was 100% for both Taenia sp and D caninum.
Atrophic rhinitis in New Zealand White rabbits infected with Pasteurella multocida
Authors: DiGiacomo Ronald F. , Deeb Barbara J. , Giddens W. Ellis , Bernard Bon L. , Chengappa M. M.
Published: February 2025

Atrophic rhinitis was detected in New Zealand White rabbits when upper respiratory tract disease was evaluated during a vaccine field trial for the prevention of pasteurellosis. Of 52 adult rabbits euthanatized and necropsied, 26 (50%) had evidence of turbinate atrophy. Atrophy was detected in 77% of rabbits with Pasteurella multocida infection only, 71% of rabbits with concurrent P multocida and Bordetella bronchiseptica infections, and 6% of rabbits with B bronchiseptica infection only. Grossly, turbinate atrophy was characterized by a mild to severe loss or diminution in the maxilloturbinates. Histologically, turbinate bones were small and irregular in thickness and had numerous osteoclasts and osteoblasts. A neutrophilic exudate filled the nasal passages, and infiltrates of neutrophils and lymphocytes were detected in the mucosa and submucosa of the nasal turbinates. Rhinitis was significantly (P < 0.001) associated with turbinate atrophy. Isolates of P multocida from rabbits with turbinate atrophy were serotype A:12.
Interleukin-2 production by mitogen-stimulated intestinal mucosal leukocytes from cattle
Authors: Nagi Abdelbagi M. , Babiuk Lorne A.
Published: February 2025

Leukocytes isolated from intraepithelium, lamina propria, and aggregated lymphatic follicles of the small intestine of healthy adult cattle were tested for their ability to produce interleukin 2 (il-2) by in vitro stimulation of cells with mitogens. Supernatants from interepithelial leukocytes, lamina propria leukocytes, and cultures stimulated with concanavalin A (conA), phytohemagglutinin, and pokeweed mitogen contained growth factors with the capacity to maintain proliferation of a bovine il-2-dependent lymphoblastoid cell line. Interleukin-2 activity was demonstrated in supernatants of all 3 conA-stimulated leukocytes populations as early as 20 hours after initiation of culture, reached peak values at 30 to 50 hours, and decreased by 72 hours. Although quantitative variations of il-2 production were observed between various cell types and among cattle, conA was the most potent in inducing il-2 activity in all 3 leukocyte populations.

Supplementaion of culture medium with 2-mercapto-ethanol or phorbol myristrate acetate neither induced il-2 production nor enhanced mitogen-induced il-2 production. Addition of indomethacin to conA-stimulated cultures enhanced il-2 production. Although depletion of adherent cells did not affect il-2 production, total eliminaiton of la-positive accessory cells inhibited its production by all 3 cell populations. Lymphocytes responsible for il-2 production in aggregated lymphatic follicle population were presumptive T cells because they were nylon wool-nonadherent, B26A positive (monoclonal antibody directed against pan T cells), pIg45A negative (antibody directed against pan B cells), and considered peanut agglutination-positive.
Thoracic and Abdominal Radiographic Abnormalities in the Multicentric Form of Lymphosarcoma in Dogs
Authors: Ackerman Norman , Madewell Bruce R.
Published: February 2025

Thoracic and abdominal radiographs from 100 dogs with lymphosarcoma were reviewed to determine the type and frequency of radiographic abnormalities associated with the disease. Sternal lymphadenopathy was the most frequent (60%) thoracic radiographic abnormality. Hepatomegaly (47%), splenomegaly (55%), and sublumbar lymphadenopathy (49.5%) were the most frequent abdominal radiographic abnormalities; these were most often seen in combination. A single radiographic abnormality or combination of abnormalities was not observed frequently enough to suggest that a diagnosis could be made only on the basis of radiographic findings.
Tracheal Resection and Anastomosis in Dogs
Authors: Lau Richard E. , Schwartz Anthony , Buergelt Claus D.
Published: February 2025

Resection and end-to-end anastomosis of the trachea is a practical procedure for the correction of various forms of tracheal stenosis. Preplacing retention sutures facilitates manipulation of the trachea and rapid apposition of the tracheal ends. These same sutures then relieve tension on the primary suture line, assuring early epithelialization.

Two dogs with tracheal stenosis were treated by use of this technique. Slight narrowing of the trachea was evident postoperatively in both dogs, but neither dyspnea nor coughing occurred during the follow-up period.
Pet Ownership in Rural Northern California (El Dorado County)
Authors: Franti C. E. , Kraus J. F. , Borhani N. O. , Johnson S. L. , Tucker S. D.
Published: February 2025

Demographic and economic aspects of pet ownership were studied in 488 households in El Dorado County, California, from May to July 1971. About 60% of households owned dogs or cats, and pet ownership was most prevalent (75%) in two small residential communities in the western end of the county. Among dogs, Poodle and German Shepherd Dog were the most popular breeds; about 36% of the females in the sample were spayed, but only 6% of the males were castrated. Approximately one third of all cats had been neutered. Reported use of veterinary services was higher for dogs (79%) than for cats (53%).

The results of the survey indicated pet ownership is most likely to be found in households with children, where the head of household is employed, generally confirming findings from earlier surveys in Yolo, Alameda, and Contra Costa Counties (all in northern California) and later surveys in Champaign County, Illinois, and Garland, Tex.

Some community health findings were included for El Dorado County and nearby Yolo County. In these two counties, cancer was reported more frequently by adults without pets (3.9% of those ≥ 65 years old) than by pet owners (1.8% of those ≥ 65 years old). Among children < 5 years old, “frequent diarrhea” was reported more commonly in homes without pets (9.5% vs 2.6%; P < 0.01). On the other hand, pet-owning adults, 16 to 64 years of age, living in rural areas or areas with generally lower than average incomes reported “frequent headaches” (21%) more frequently than did adults without pets (17%; P < 0.025%) who resided in the same areas.
Salmonellosis in a Group of Ponies: Failure To Identify a Chronic Active Carrier
Authors: Smith Bradford P. , Timm Karen , Jahn Sharon , Reina-Guerra Mario
Published: February 2025

Three of 33 ponies died after the herd had been moved to a new environment 3 months earlier. One mare died without premonitory signs of illness. Shortly thereafter, a 5-day-old foal and a 2-year-old gelding died after brief illness. Although cultures were not performed on the mare, Salmonella typhimurium was isolated from the feces and tissues of the foal and gelding. Lesions in the foal were confined to ecchymotic hemorrhages on the mucosal surface of the colon and petechial hemorrhages in the splenic capsule, with adhesions to the parietal peritoneum. The gelding had evidence of severe typhlitis and colitis.

Subsequent culturing of feces from all ponies for 5 consecutive days revealed five ponies shedding S typhimurium, including the dam of the dead foal, the 6-week-old foal of the dead mare, and three others. Phage typing indicated that all isolants were of the same type. Weekly fecal cultures of all ponies for the next 9 weeks revealed that 1 month after the initial cultures, none of the ponies was shedding Salmonella. Monthly cultures for the next year did not yield any growth of Salnomella, indicating there was no active carrier (shedder) in the herd. The source of Salmonella that initiated the outbreak was not found, in spite of environmental culturing.
Occlusion of Internal Carotid Artery in the Horse by Means of a Balloon-Tipped Catheter: Evaluation of a Method Designed To Prevent Epistaxis Caused by Guttural Pouch Mycosis
Authors: Freeman David E. , Donawick William J.
Published: February 2025

A procedure developed to occlude the internal carotid artery of horses with guttural pouch mycosis was modified and evaluated in nine clinically normal horses. The left internal carotid artery was ligated at its origin and occluded distally with an intraluminal balloon catheter.

In four horses, the balloon-tipped catheters were left in place until these horses were euthanatized at 4 to 244 days after surgery. In the remaining horses, the catheters were removed after 10 to 14 days by a cutdown procedure, and these horses were euthanatized 1 to 60 days after catheter removal. In both groups, gross and histologic examinations revealed that occlusive thrombosis had developed in sections of artery distal to the balloon. Postoperative complications were not encountered.
Pseudoachondroplastic Dysplasia in Miniature Poodles: Clinical, Radiologic, and Pathologic Features
Authors: Riser Wayne H. , Haskins Mark E. , Jezyk Peter F. , Patterson Donald F.
Published: February 2025

The clinical, radiologic, and pathologic features of pseudoachondroplastic dysplasia were studied in 13 affected Miniature Poodles. The disease became evident when pups were about 3 weeks old. Normal-appearing and affected pups were in the same litter, and both sexes were affected. Abnormal locomotion with abducted hindlimbs and flattened rib cages were accompanied by short, bent limbs and enlarged joints. Radiographically, areas of stippling and patchy densities were evident in the epiphyses. Histologically, these densities were identified as areas of bone associated with retarded ossification. After growth is completed, the epiphyses ossify, but the bones are shortened and deformed. General health appears normal, except for restricted locomotion due to secondary arthritis and difficult breathing in dogs with a deformed thorax.
Acquired Peripheral Arteriovenous Fistula in a Dog
Authors: Butterfield Arthur B. , Hix William R. , Pickrel Jerry C. , Johnson Karen E.
Published: February 2025

A pulsating mass with a continuous bruit was discovered in a dog's flank during routine examination. Based on a history of trauma and clinical signs, an acquired arteriovenous (av) fistula and a false aneurysm were included in the differential diagnosis. Arteriography confirmed the presence of an av fistula and outlined the lesion for successful surgical extirpation. Histopathologic characteristics of the av fistula were similar to those in man.
Veterinary Services to the Pennsylvania Sheep Industry
Authors: Donoghue Susan , Kronfeld David S. , Menhennett Annette
Published: February 2025

Questionnaires on ovine management and disease were distributed to sheep producers and large animal veterinarians in Pennsylvania. Returns indicated economic analysis of veterinary services to eastern farm flocks to be of primary importance. Although most producers were reluctant to request veterinary services because of cost, the average expenditure for veterinary services was reasonable ($143 per flock per year). Producers appeared to have little awareness of expected benefits from veterinary services. It was concluded that coordination of veterinary services and producer management should increase production and economic returns. Determination of cost/benefit ratios for individual and flock veterinary care would allow for formulation of sound flock health programs and would demonstrate effectiveness of such programs to producers and veterinarians.
Spontaneous Shedding of Pseudorabies Virus from a Clinically Recovered Postparturient Sow
Authors: Davies E. B. , Beran G. W.
Published: February 2025

Pseudorabies virus was shed by a sow that had been clinically infected 19 months earlier (when 1 month old) and had been in isolation for 3½ months. The shedding was detected from the third to eighth days after farrowing and was confined to the nasal secretion. Two susceptible pigs in Contact with the sow after farrowing were not infected.
Photosensitization of Sheep on Kleingrass Pasture
Authors: Muchiri D. J. , Bridges Charles H. , Ueckert Darrell N. , Bailey E. M.
Published: February 2025

The clinical appearance and serum gammaglutamyl transpeptidase (ggt) activity were studied in 5 groups of sheep (12 per group) on kleingrass (Panicum coloratura) pasture plots and in 1 group of sheep (10 animals) on native buffalograss (Buchloë dactyloides) pasture. Eleven sheep (at least 1 from each group on kleingrass pasture plots) had elevated serum ggtactivity. Seven of 11 sheep with elevated serum ggtactivity developed signs of photosensitization. None of the sheep on buffalograss pasture developed signs of photosensitization or elevated ggtactivity.

The pathologic findings were similar in the sheep that had signs of photosensitization. Grossly, there was icterus and subcutaneous edema. The livers had tapeworms (Thysanosoma actinioides) in the bile ducts, were slightly swollen, and varied in color from yellow to ochre in severe cases of biliary system derangements. Microscopically, there was cholangitis.
Objectionable Urine Spraying and Urine Marking in Cats: Evaluation of Progestin Treatment in Gonadectomized Males and Females
Authors: Hart Benjamin L.
Published: February 2025

The increasing use of long-acting progestins to treat objectionable urine spraying and urine marking in gonadectomized cats prompted a survey of the comparative effectiveness of the injectable medroxyprogesterone acetate (mpa) and the orally administered megestrol acetate (ma). Both drugs were successful, overall, in about 1/3 of the patients. However, the proportion with favorable response was higher for males (48%) than for females (13%) and was higher for cats from single-cat homes (50%) than for cats from multi-cat homes (18%). Because of the reportedly higher frequency of depression and increased appetite following ma treatment, when compared with mpa treatment, it is recommended that mpa be used initially for routine treatment of these behavioral problems. The survey revealed that if mpa proves ineffective, subsequent treatment with ma can be expected to yield favorable results in some of these patients.
Seasonal Influence on the Fertility of Sows and Gilts
Authors: Hurtgen John P. , Leman Allen D.
Published: February 2025

Seasonal fluctuations in the farrowing rates (fr) of sows and gilts were determined by analysis of breeding records from 11 herds, covering a total of 26 herd-years of data. Of 22,997 sow and gilt matings, 72.7% resulted in farrowing. For matings during July, August, and September, 60.8% of females farrowed, compared with 76.9% for matings during the remainder of the year. The fr was higher in multiparous sows than in primiparous sows and was lowest in nulliparous gilts. The fr was 65.5% for gilts bred in confinement and for gilts maintained outside. The seasonal fluctuation in fr was similar for confinement and outside-housed gilts. Water sprinkling or evaporative cooling methods did not prevent seasonal fluctuations in the fr of sows or gilts. For sows confined to crates after breeding, the fr was 13.8% higher than for sows in group-housing systems, but the seasonal fluctuation in fr was not substantially altered.

It was concluded that the fr of female swine is markedly influenced by season of the year and by parity. The seasonal fluctuations in fr occurred in group- and individually housed swine and in confinement and outside-bred gilts. Water sprinkling or evaporative cooling systems, as used in the herds investigated, appeared to be of questionable value in preventing infertility during the warm months.
Oral Eosinophilic Granuloma in Siberian Husky Dogs
Authors: Madewell B. R. , Stannard A. A. , Pulley L. T. , Nelson V. G.
Published: February 2025

Oral eosinophilic granuloma in 6 young Siberian Husky dogs was characterized by involvement of lateral and ventral surfaces of the tongue. Histologically, the major change was degenerated (necrobiotic) collagen. Although the cause of the disease is unknown, hereditary and immunologic factors are implicated in the pathogenesis.
Intra-Articular Corticosteroid Therapy in the Horse
Authors: Owen Rh. ap Rh.
Published: February 2025

Physiologic features of the equine diarthrodial joint and the effects of intra-articular corticosteroid therapy were investigated. It was concluded that intra-articular injection of corticosteroids may be beneficial when lesions are confined to soft tissues of the joint, excluding injuries involving joint laxity. Rest following therapy is important.
Temperature of the Artificial Vagina and Its Effect on Seminal Quality and Behavioral Characteristics of Stallions
Authors: Hillman R. B. , Olar T. T. , Squires E. L. , Pickett B. W.
Published: February 2025

Stallion semen was collected, using artificial vaginas at 44 to 46, 48 to 50, and 52 to 54 C, to study the effects of temperature on seminal quality and sexual behavior. The temperature of the artificial vagina had no significant effect on motility, gel volume, gel-free seminal volume, total seminal volume, pH, number of mounts per ejaculate, total time to ejaculation, or seminal temperature.

Spermatozoa were collected, then exposed to water-bath temperatures of 38, 45, 49, or 53 C for 1 minute. Mean motility was similar after exposure to temperatures of 38 or 45 C, but exposure to temperatures of 49 or 53 C resulted in a significant decrease (P < 0.05) in spermatozoal motility with each increase in temperature. Thus, it was concluded that spermatozoa exposed to temperatures greater than 45 C may be irreversibly damaged.
Survey for Antibodies to Viruses of Bovine Virus Diarrhea, Bluetongue, and Epizootic Hemorrhagic Disease in Hunter-Killed Mule Deer in New Mexico
Authors: Couvillion Charles E. , Jenney Edwin W. , Pearson James E. , Coker Michael E.
Published: February 2025

Sera from male mule deer (Odocoileus hemionus) collected in November 1977 in Otero County, New Mexico were tested for antibodies to bovine virus diarrhea virus (bvdv), bluetongue virus (btv), and epizootic hemorrhagic disease virus (ehdv). Neutralizing antibodies were detected in 26 of 76 (34%) sera tested for bvdv (titer ≥ 1:16). Of 46 sera tested for antibodies to btv and ehdv, 10 (22%) and 3 (7%), respectively, were positive. Three (7%) of 46 sera were suspect (titer < 1:20) for btv, and 18 (38%) sera were suspect (titer < 1:20) for ehdv.
Paramyxo-like Virus Infection in a Rock Rattlesnake
Authors: Jacobson Elliott , Gaskin Jack Μ. , Simpson Charles F. , Terrell Timothy G.
Published: February 2025

A rock rattlesnake (Crotalus lepidus) with a history of progressive central nervous disease was submitted for necropsy. The histopathologic findings included evidence of interstitial pneumonia, multifocal areas of gliosis in the brain, and ballooning degeneration and demyelination of brainstem and upper spinal cord axons. By electron microscopy, brainstem tissue was found to contain numerous virus particles in the extracellular spaces. A paramyxo-like virus, isolated in viper heart cells from lung tissue, was observed by electron microscopy to be similar in size and shape to the particles seen in nerve tissue.
Mixed Infection in Columnaris Disease of Fish
Authors: Marks J. E. , Lewis D. H. , Trevino G. S.
Published: February 2025

In addition to Flexibacter columnaris, Corynebacterium sp was recovered from lesions associated with columnaris disease in catfish. Catfish exposed to pure cultures of the Corynebacterium sp developed circumscribed lesions, which regressed without further adverse effects. Disease signs were not demonstrable in catfish exposed to pure cultures of F columnaris; however, when catfish were exposed to mixed cultures of the Corynebacterium sp and F columnaris, signs of columnaris appeared and the fish died.
Mucormycosis in Hatchling Florida Softshell Turtles
Authors: Jacobson Elliott R. , Calderwood Maron B. , Clubb Susan L.
Published: February 2025

Six hatchling softshell turtles selected from a group of approximately 400 with circular gray integumentary lesions were submitted for clinical evaluation. The turtles died within 24 hours. Histologic examination of the carapace revealed ulcerative epidermitis, with bacterial colonies and tightly packed groups of fungi. A Mucor sp was isolated from the lesions.
Blastomycosis in an African Lion
Authors: Stroud Richard K. , Coles Barbara Μ.
Published: February 2025

Using fluorescent antibody techniques, Blastomyces dermatitidis was identified in pyogranulomatous lesions in the lungs, mediastinum, trachea, and cerebrum of an African lion (Panthera leo). Clinical signs included anorexia and dry inspiratory rales. Signs of nervous system dysfunction were not reported prior to death even though a large lesion was found in the cerebrum at necrospy.

The lion was shipped from a geographic area where B dermatitidis infection is endemic. It was evident from histologic studies that organisms were being shed from lesions in the trachea into the environment. We were unable to culture the organism because freezing apparently destroyed its viability.
Disseminated Hexamitiasis in Siamese Fighting Fish
Authors: Ferguson H. W. , Moccia R. D.
Published: February 2025

One hundred forty Siamese fighting fish became inappetent and lethargic and developed swollen abdomens. One hundred fish died, many with perforated stomachs. Hexamitid parasites were found in large numbers in the abdominal cavity and in the mesentery and the parenchyma of the liver, spleen, and kidney, where they were closely associated with a chronic inflammatory response. Species of bacteria recovered from the peritoneal cavity were believed to be secondary invaders. The 40 surviving fish, including some sick ones, were treated with nifurpirinol at the rate of 0.2 mg/L and 5 mg/kg of body weight, by means of a bath and a feed medication, respectively. The sick fish recovered, and no more died.
Diagnosis and Repair of Familial Diaphragmatic Defects in Golden Lion Tamarins
Authors: Bush Mitchell , Montali Richard J. , Kleiman D. G. , Randolph Judson , Abramowitz Michael D. , Evans Ronald F.
Published: February 2025

Diaphragmatic defects were identified in 11 of 130 golden lion tamarins. Seven of the cases were found at necropsy (52 tamarins) and 4 were diagnosed by radiography (78 tamarins). When screening radiography revealed a thoracic mass, a barium series was indicated and either demonstrated loops of bowel within the thorax or suggested liver displacement by the cranial location of the intestine. In 1 case, pneumoperitoneum aided in the diagnosis, by showing liver displacement cranially in an eventration of the diaphragm.

The 4 defects diagnosed clinically were successfully corrected surgically. The defects mainly involved the ventromedial to lateral aspect of the costal and sternal muscular portions of the diaphragms. Either a thin pleuroperitoneal sac remained or wide gaps were associated with herniation of abdominal contents into the thorax.

Of the 11 affected tamarins, 10 were closely related and the other had no direct consanguinity. An autosomal recessive mode of inheritance was suggested, but other genetic factors may have been involved.
Physiologic and Acid-Base Measures of Gopher Snakes During Ketamine or Halothane-Nitrous Oxide Anesthesia
Authors: Custer Randy S. , Bush Mitchell
Published: February 2025

Arterial acid-base and selected physiologic measures of gopher snakes (Pituophis melanoleucus catenifer) during ketamine or halothane-nitrous oxide anesthesia were compared with base-line values. During ketamine anesthesia, significant decreases in pH and concentrations indicated acid-base states of uncompensated metabolic acidosis. In contrast, halothane-nitrous oxide anesthesia induced acidosis of respiratory origin, through a significant depression in respiratory rate.

In addition to the conventional measures, the OH−/H+ ratios and the alpha-imidazole (αIM) values were calculated to assess acid-base status during anesthesia. Values for both factors decreased significantly during both ketamine and halothane-nitrous oxide anesthesia. Where H+ concentrations nearly doubled, the decline in the OH−/H+ ratio exceeded 70% and the αIM decreased less than 20%. It was concluded that these 2 factors may be helpful in evaluation of the acid-base status of ectothermic animals when normal values for the conventional measures of pH and pCO2 are not available for comparison.
Stabilization of Atlantoaxial Subluxation in the Dog, Using the Nuchal Ligament
Authors: LeCouteur R. A. , McKeown D. , Johnson J. , Eger C. E.
Published: February 2025

A technique for the stabilization of atlantoaxial subluxation in the dog was developed. The technique involved use of the nuchal ligament as a means of securing the spinous process of the axis to the dorsal arch of the atlas.

Two cases were typical atlantoaxial subluxation in toy-breed dogs, and 2 cases were traumatic subluxation secondary to fracture of the axis in dogs of large breeds. On the basis of the results in these cases, it was concluded that the technique has advantages over techniques in which wire or nonmetallic suture material is utilized for stabilization.
Persistence of Encysted Toxoplasma gondii in Caprine Livers and Public Health Significance of Toxoplasmosis in Goats
Authors: Dubey J. P.
Published: February 2025

The distribution of encysted Toxoplasma gondii was compared in livers, kidneys, and musculature of experimentally (n = 12) and naturally (n = 10) infected goats.

The 12 experimentally infected goats were killed 7, 10, 14, 17, 18, 19, 59, 83, 83, 86, 88, and 90 days after inoculation (dai) with 100 or 1,000 infective T gondii oocysts. Pepsin digests of liver, kidneys, heart, diaphragm, skeletal muscle, and brain were inoculated into mice for the detection of T gondii cysts in caprine tissues. For the goats killed between 14 and 90 dai, T gondii was demonstrated in the liver and skeletal muscle of 9 of 10, kidneys of 7 of 10, brain of 5 of 10, diaphragm of 5 of 10, and heart of 3 of 8. The organism was demonstrated in skeletal muscle but not from other tissues of the goat killed 10 dai or from any of the tissues of the goat killed 7 dai.

Tissues of the 10 naturally infected goats also were examined for T gondii cysts, by inoculating mice with pepsin digests of the tissues. Encysted T gondii were found in the liver of 3 of 10, kidneys of 3 of 10, brain of 3 of 10, diaphragm of 6 of 9, heart of 6 of 9, and skeletal muscle of 10 of 10.

The results demonstrated that T gondii cysts frequently develop in liver and kidneys of goats and that cysts persist longer in skeletal muscle than in brain. It was concluded, for public health reasons, that livers or other tissues from goats should be cooked before use, to kill T gondii.

The excretion of T gondii in milk of goats also was studied by inoculation of mice with milk samples from 7 experimentally infected and 7 naturally infected goats. Toxoplasma gondii was demonstrated in the milk of a goat infected with 10,000 infective oocysts but not in goats infected with 100 or 1,000 oocysts or in naturally infected goats. Of the 182 mice inoculated with 57 milk samples from a goat infected with 10,000 oocysts, 10 acquired toxoplasmosis; however, only 1 of 335 mice became infected after inoculation with 111 milk samples from 6 goats infected with 100 or 1,000 oocysts, and none of 263 mice became infected with T gondii after inoculation with 68 milk samples from 7 naturally infected goats. It was concluded that the chance of T gondii being in the milk of naturally infected goats is very small and, as the stage likely to be present would be tachyzoite which is destroyed by gastric juice, the risk of human infection would seem to be infinitesimal.
Canine and Feline Urinalysis: Value of Macroscopic and Microscopic Examinations
Authors: Barlough Jeffrey E. , Osborne Carl A. , Stevens Jerry B.
Published: February 2025

A retrospective survey of complete urinalyses performed on dogs and cats hospitalized at the University of Minnesota Veterinary Teaching Hospital was performed to determine the frequency of abnormal findings in urine sediment, compared with normal and abnormal macroscopic findings. One thousand consecutive urine samples collected from dogs and 1,000 consecutive urine samples collected from cats were studied. Results indicated that failure to examine urine sediment of macroscopically normal samples would have yielded false-negative results in 16.5% of the canine patients and 5.7% of the feline patients. Microscopic findings in macroscopically normal canine samples consisted primarily of pyuria and bacteriuria, whereas in cats they consisted of hematuria and bacteriuria. Microscopic abnormalities were detected in almost 50% of the canine and feline samples with macroscopic abnormalities. The results of this evaluation confirm the value of routine microscopic examination of urine sediment as a component of complete urinalysis.
Malignant Tumor Formation at the Site of Previously Irradiated Acanthomatous Epulides in Four Dogs
Authors: Thrall Donald E. , Goldschmidt Michael H. , Biery Darryl N.
Published: February 2025

The radiation response of acanthomatous epulis in 32 dogs was good, with an estimated median survival time of 21 months. Of the 32 patients, 14 have died. In 4 of those 14, malignant tumors developed at the site of the acanthomatous epulis. The tumors were of epithelial origin in 3 patients and of mesenchymal origin in 1 patient. Possibilities explaining the appearance of the malignancies included spontaneous malignant transformation, radiation induction of neoplasms, and radiation induction of malignant transformation. This uncommon complication was not considered contradictory to radiotherapy of acanthomatous epulides, because of their excellent response to irradiation and the long latent period between irradiation and appearance of the malignant tumor.
Pulmonary Artery Thrombosis in Three Dogs with Hyperadrenocorticism
Authors: Burns Mark G. , Kelly Andrew B. , Hornof William J. , Howerth Elizabeth W.
Published: February 2025

Varying degrees of respiratory distress developed in 3 dogs in which hyperadrenocorticism was diagnosed. The respiratory distress was attributed to pulmonary artery thrombosis. Radiography revealed pleural effusion, increased diameter and blunting of the pulmonary arteries, lack of perfusion of the obstructed pulmonary vasculature, and overperfusion of the unobstructed pulmonary vasculature. Thrombosis was confirmed by nonselective angiocardiography in each case. In 1 case, selective angiocardiography showed marked reduction of the transit time of contrast medium from the right atrium to the aorta. Hypertension proximal to the site of thrombosis was confirmed in 2 cases by showing increases in the right ventricular systolic pressures (80 mm of Hg in one case and 54 mm of Hg in the other case). In 3 cases, there was moderate hypoxemia with hypocapnia, suggesting a ventilation-perfusion mismatch. Clinical findings other than respiratory distress included hepatomegaly, ventral edema, orthopnea, and a jugular pulse.

Pulmonary artery thrombosis, as it occurred in these 3 cases, was compared with the disease in man. It was concluded that pulmonary artery thrombosis should be suspected in cases of intractable dyspnea, right-sided heart failure of unexplained origin, and acute unexplainable death.
Hematologic Abnormalities Preceding Apparent Recovery from Feline Leukemia Virus Infection
Authors: Lester S. J. , Searcy G. P.
Published: February 2025

A 5-month-old domestic short-haired cat was referred to the Western College of Veterinary Medicine because of hemorrhage from the mouth. Neutropenia and bone marrow dyscrasia developed within 2 weeks, and results of a fluorescent antibody test for feline leukemia virus (FeLV) were positive.

During the next 6 months, the feline oncornavirus cell membrane-associated antibody titer increased, the hematologic abnormalities regressed, and the cat became negative to the FeLV fluorescent antibody test (FeLV test). The results of 3 consecutive FeLV tests were negative, and the cat has been clinically normal for the past 18 months.
Epizootic Toxoplasmosis Associated with Abortion in Dairy Goats in Montana
Authors: Dubey J. P.
Published: February 2025

Perinatal toxoplasmosis was diagnosed in goats from 2 farms in Montana. Of 7 pregnant does from one farm, 1 aborted a dead fetus and 2 each had a kid infected in utero. Toxoplasma gondii was demonstrated histologically in the placenta of 2 of the infected does and by mouse inoculation in all 3 of them. The organism also was isolated from internal organs of 6 of 7 does, 4 of 4 cats, and 3 of 11 chickens from the farm. A pregnant doe from the other farm delivered 3 kids infected with T gondii. One kid was born dead, 1 was moribund when born, and 1 was healthy when born. Toxoplasma gondii was isolated from the placenta and several tissues of all 3 kids.
Toxoplasma-Induced Abortion in Dairy Goats
Authors: Dubey J. P.
Published: February 2025

Fifteen pregnant goats serologically negative for Toxoplasma gondii were inoculated orally with 10, 100, or 1,000 infective oocysts of the GT-1 strain of T gondii. Four goats received 10 oocysts, 6 received 100 oocysts, and 5 received 1,000 oocysts. Six pregnant goats served as noninoculated controls. All inoculated goats became pyretic (40-41 C) and were dyspneic between 4 and 12 days after inoculation (dai). Two goats inoculated in early pregnancy (68 and 70 days) with 100 oocysts had enlarged uteri; fetal membranes but no fetuses were found when they were killed 86 and 88 dai. Three goats aborted or had a stillborn kid 9, 10, and 11 dai. The remaining 10 goats delivered kids infected with T gondii; 8 goats had at least 1 stillborn kid, and 2 goats had infected but otherwise normal kids at birth.

Placenta and tissues of fetuses and kids were inoculated into mice for determination of Toxoplasma infectivity. Toxoplasma gondii was isolated from the fetal placenta of 6 of 7 goats as early as 10 dai and as late as 62 dai. The organism was isolated from every fetus or kid that was born 18 dai but not from fetuses or kids born 9, 10, and 11 dai. Two kids were born 15 dai; T gondii was isolated from 1 kid but not from the other, suggesting that T gondii invaded fetal tissues between 11 and 15 dai. Of the 20 transplacental^ infected kids, T gondii was isolated more frequently from the skeletal muscle, heart, lung, and brain than from other tissues.