bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of autogeneic and allogeneic cortical chip grafting in a feline tibial nonunion model
Authors: Toombs James P. , Wallace Larry J.
Published: February 2025

A feline tibial nonunion model was used to evaluate the efficacy of fresh autogeneic and deep-frozen allogeneic cortical chip grafts for bone repair. Rigidly fixated tibial ostectomies with a segmental defect length of 1 cm were grafted with 3 mm × 2 mm chips of cortical bone in 12 skeletally mature cats. Six cats were given fresh autogeneic bone (group A) and 6 were given deep-frozen allogeneic bone (group B). Bone healing was evaluated radiographically and histologically over a 12-week period.

Consolidating bony callus and palpable stability of the tibia after bone plate removal were evident in all group A cats and 4 of the 6 group B cats by 12 weeks after surgery. Bone remodeling had progressed to intermediate restoration of diaphyseal structure in 2 cats of each group.

Fibrous replacement of graft chips, absence of bony callus, and instability of the tibia after bone plate removal were evident in 1 group B cat at 12 weeks. The remaining group B cat was withdrawn from the study at 6 weeks due to loosening of the bone plate and screws.
Multielement assays of bovine tissue specimens by inductively coupled argon plasma emission spectroscopy
Authors: Stowe Howard D. , Braselton W. Emmett , Kaneene John B. , Slanker Michael
Published: February 2025

Inductively coupled argon plasma spectroscopy was used to generate multielement profiles of bovine serum (n = 607), liver (n = 229), and kidney (n = 90) samples submitted to the Animal Health Diagnostic Laboratory at Michigan State University, East Lansing. The presented frequency distribution histograms of element concentrations in the different samples provided a data base for diagnostic interpretations and illustrated some of the advantages, as well as limitations, of inductively coupled argon plasma for this purpose.
Evaluation of the wick catheter as used to measure intracompartmental muscle pressure in equine muscle
Authors: McDonell W. N. , Pascoe P. J. , Lindsay W. A. , Burgess M. L. F.
Published: February 2025

The use of the wick catheter to measure intracompartmental muscle pressure in equine muscle was documented. The presence of muscle compartments involving the extensor carpi radialis muscle and the long head of the triceps brachii was demonstrated by anatomic dissection and radiographic technique. The wick catheter was capable of accurately measuring pressures within both of these compartments. Furthermore, the wick catheter was sensitive to pressure changes resulting from external compression of muscle compartments. Manipulation of systemic blood pressure and PaCO2 in 1 anesthetized horse did not affect intracompartmental muscle pressure.
Fascial compartments of the equine crus
Authors: Updike Susan J.
Published: February 2025

The deep fascia of the equine crus was dissected grossly and separated into 2 layers, the superficial and deep laminae of the deep fascia. Attachments of these fascial laminae to the tibia and fibula formed 5 separate osteofascial compartments: cranial, lateral, caudal deep, caudal intermediate, and caudal superficial. Cranial tibial vessels and the deep peroneal nerve entered the cranial compartment through separate fascial hiatuses; this may predispose the equine crus to the occurrence of compartmental syndromes with clinically recognizable neural deficits.
Laparoscopic-assisted serial biopsy of the bovine kidney
Authors: Naoi Masayuki , Kokue Ei-ichi , Takahashi Yuji , Kido Yasumasa
Published: February 2025

A serial renal biopsy with endoscopy was done, using 10 calves and a cow. In 8 of the calves, biopsy materials were collected 3 to 5 times over a period of 15 to 41 days. A laparoscope was inserted into the peritoneal cavity from the center of the right paralumbar fossa through the outer cannula of the trocar. Under laparoscopic observation, the renal parenchyma was collected with the cutting prong of a biopsy needle. Of 34 biopsy attempts, 32 were successful; in 2, there was incomplete penetration of the trocar assembly into the peritoneal cavity. In one instance, the trocar was misguided to the small intestine which was closely adherent to the peritoneum. The error may have been the result of the presence of a persistent blood clot resulting from the preceding biopsy. An immediate saline rinse of the blood clot attached to kidney and the surrounding tissues was effective in preventing such adhesions.

The size of the average sample obtained was 1.5 mm in diameter and 16 mm (2 to 40 mm) long. The tissues were collected in 61 times from the 72 insertions of the biopsy needle to the renal tissue. The 11 unsuccessful attempts were caused by bluntness of the cutting parts of the needle. Adverse clinical signs were not observed after the serial biopsy of kidney, except for the presence of blood in the urine persisting for 1 to 5 days. Although a dehydrated blood clot was found in the renal pelvis of one animal at necropsy, any complication such as obstruction of urinary flow was not observed.
Heavy metals in tissues of cattle exposed to sludge-treated pastures for eight years
Authors: Fitzgerald Paul R. , Peterson James , Lue-Hing Cecil
Published: February 2025

Cattle allowed to graze pastures variously treated with anaerobically digested sludge (ads) for up to 8 years, contained higher concentrations of heavy metals and organic compounds in some tissues than did cattle not exposed to ads. Chemical analyses were made on heart, diaphragm, liver, kidney, brain, and bone to determine the amount of Zn, Cu, Cd, Cr, Ni, Pb, Fe, and Hg. Determinations for organic compounds (polychlorinated-biphenyls, dieldrin, and heptachlor/epoxide) were made on visceral fat. Cadmium was the only metal to accumulate consistently in increased amounts. Amounts of Cd accumulated in kidneys and livers were higher in cattle exposed to ads than in cattle not exposed to ads. Although the amounts were higher in cattle exposed to ads, none of the cattle had detectable evidence of disease or pathologic conditions. The mean amount of Cd in kidneys of cattle exposed to ads was 44 vs 9 mg/kg dry weight. Amounts of other heavy metals in the body tissues were generally not unusual and were similar in both groups of cattle. Polychlorinated-biphenyl concentrations were higher in the visceral fat of cattle exposed to ads. All cattle in both herds remained healthy, and pathologic changes that could be attributed to association with ads were not detected. Seemingly, ads can be used safely to produce cattle forage without endangering the health of cattle.
Effects of endotoxemia on lung water and hemodynamics in conscious calves
Authors: Olson Neil C. , Brown Talmage T.
Published: February 2025

The effects of endotoxemia on cardiovascular and pulmonary parameters were determined in conscious, 4- to 6-week-old calves. Escherichia coli endotoxin was infused continuously (4 μg/kg/hr, iv) for 5 hours. During endotoxemia, pulmonary vascular resistance and mean pulmonary artery pressure increased, and cardiac index, central plasma volume, and mean systemic arterial pressure decreased. Neutrophil, lymphocyte, and platelet counts also decreased. During the first hour of endotoxemia, PaO2 decreased, and alveolar-arterial O2 gradient and shunt fraction increased. Lung extravascular thermal volume was increased from 2 to 5 hours. Postmortem extravascular lung water/extravascular dry weight ratio, bronchoalveolar lavage albumin, and poly morphonuclear cell content did not change. Microscopically, the septal capillaries of endotoxemic calves were dilated and engorged with erythrocytes, accompanied by focal accumulations of neutrophils. Intraalveolar edema and hemorrhage were not seen.
Application of the peroxidase-antiperoxidase procedure to the localization of pituitary hormones and calcitonin in various domestic animals and human beings
Authors: Sandusky George E. , Wightman Karen A.
Published: February 2025

Specific cell populations in the pituitary glands of the rat, cat, pig, and human being were positive for thyroid-stimulating hormone (tsh), luteinizing hormone (lh), and follicle-stimulating hormone (fsh). When reacted with prediluted rabbit anti-human tsh, lh, and fsh, antisera were not positive for the demonstration of these hormones in the horse, cow, or dog. Immunocytochemical staining was obtained in the horse, cow, and dog by the use of a primary antiserum against a specific β-subunit of bovine tsh.

The immunocytochemical staining of tsh, lh, fsh, adrenocorticotropic hormone, growth hormone, prolactin, and calcitonin was examined by the peroxidase-antiperoxidase method, using standard commercially available kits. All species examined had a strong positive reaction in specific pituitary cell populations for adrenocorticotropic hormone, growth hormone, and prolactin. Sections of normal thyroid gland tissue had positive staining of C cells containing calcitonin at the dilution of 1:100 of the primary antibody in the rat, horse, cow, dog, cat, pig, and human being.
Intravenous histamine administration in ponies with recurrent airway obstruction (heaves)
Authors: Derksen F. J. , Scott D. , Robinson N. E. , Slocombe R. F. , Armstrong P. J.
Published: February 2025

Pulmonary function and airway reactivity to iv histamine were measured in a group of ponies with a history of recurrent airway obstruction (heaves) and their age-, weight-, and gender-matched controls. Ponies were studied during a period of clinical remission (period A), after exposure to a barn environment (period B), and twice during a 2-week recovery phase (periods C and D). At periods A, C, and D, PaO2, dynamic compliance (Cdyn), pulmonary resistance, tidal volume, respiratory frequency, and the log dose of histamine required to reduce Cdyn to 65% of base-line value (log ED65Cdyn) of principals and controls did not differ. Barn exposure (period B) decreased Cdyn, PaO2, and ED65Cdyn and increased pulmonary resistance in principals but not controls. The slope of the histamine dose-Cdyn response curves was not different between principal and control groups of ponies and was unaffected by barn exposure or return to pasture. There was a poor correlation between ED65Cdyn and indices of airway caliber.

During acute airway obstruction, ponies with a history of heaves were hyperreactive to iv histamine, but during disease remission, airway response to histamine was not different from that of control ponies. Seemingly, hyperreactivity in principal ponies after exposure to a barn environment cannot be explained solely by alterations in base-line airway caliber.
Rapid enzyme-linked immunosorbent assay for detecting antibodies to canine parvovirus
Authors: Fiscus Susan A. , Mildbrand Michael M. , Gordon John C. , Teramoto Yoshio A. , Winston Scott
Published: February 2025

A rapid screening assay for determining antibodies to canine parvovirus in dog serum using monoclonal antibodies and enzyme-linked immunosorbent assay (elisa) technology was developed. The elisa could be read visually, and the results correlated well with serum neutralization (sn) and hemagglutination inhibition (hi) titers. Sera with sn ≤ 1:4 or hi ≤ 1:10 had an 87.9% correlation with elisa and sera with sn ≥ 1:64 or hi ≥ 1:80 had a 94.4% correlation. The assay took only 10 to 15 minutes to perform and did not require specialized equipment. The elisa should be useful in monitoring dogs for the presence of maternal antibodies against parvovirus and for determining seroconversion after vaccination.
Serologic studies of bovine respiratory syncytial virus in Minnesota cattle
Authors: Baker John C. , Ames Trevor R. , Markham R. J. F.
Published: February 2025

Serum antibody titers to bovine respiratory syncytial virus were determined for 559 cattle. Serum samples were obtained through the Minnesota State-Federal Brucellosis Laboratory and were collected over a 1-year period. Results of this study revealed an antibody prevalence of 65.5% to bovine respiratory syncytial virus. The distribution of antibody titers is presented, as well as analysis of titers based on breed, sex, and age of the cattle.
Serologic classification of two ovine adenovirus isolates from the central United States
Authors: Adair Brian M. , McKillop Eileen R. , McFerran J. Brian
Published: February 2025

Two ovine adenovirus (oav) strains (RTS-42 and RTS-151), isolated from lambs in the central United States, were compared using 2-way cross-neutralization tests with the 6 recognized oav species, 9 bovine adenovirus species, and 4 porcine species. Virus RTS-42 was identified as oav type 5, confirming previous results. Virus RTS-151 was identified as oav type 6, although the serologic crossing was largely one-sided.
Retroviral-associated eosinophilic leukemia in the cat
Authors: Lewis Mark G. , Kociba Gary J. , Rojko Jennifer L. , Stiff Mary I. , Haberman Allan B. , Velicer Leland F. , Olsen Richard G.
Published: February 2025

Fourteen specific-pathogen-free cats were inoculated with a putative env gene recombinant feline retrovirus, PR8. An isolate of the Rickard strain of feline leukemia virus (FeLV-R), PR8, has the properties of both an exogenous (FeLV-R) and an endogenous (xenotropic) feline retrovirus (RD-114). Twelve of the PR8-inoculated cats developed viremia; 2 of the 12 cats developed eosinophilia, with 1 being diagnosed with eosinophilic leukemia and the other with extreme eosinophilic hyperplasia. Eosinophilic leukemia is rare in cats and has not previously been associated with retroviral infection. Changes in the viral envelope properties may have altered the pathogenicity of the exogenous virus to cause this rare form of leukemia.
Screening for neonatal isohemolytic anemia in calves
Authors: Luther D. Gene , Cox Hollis Utah , Nelson Walter O.
Published: February 2025

Anti-erythrocytic immunoglobulins in serum and colostrum of 124 anaplasmosis-vaccinated cows were detected with a saline agglutination test. Positive results were correlated with the occurrence of neonatal isohemolytic anemia (nia) in calves and were used to predict the occurrence of nia. The disease was prevented by withholding colostrum from calves with a high potential for nia.
Effects of storage conditions on bovine carrier erythrocytes
Authors: DeLoach John R.
Published: February 2025

Bovine carrier rbc containing [14C]sucrose as a marker were stored for 23 days in protein-free media. Cell recovery was highest with a phosphate buffer (pH 7.0) containing 2 mM MgCl2, 5 mM inosine, 5 mM adenosine, and 10 mM glucose. A cell recovery of 60% was observed after 23 days of storage at 4 C. Stored carrier erythrocytes reinjected into cattle had an 18-day half-life, which is less than that for fresh carrier rbc.
Infection of early bovine embryos with bovine herpesvirus-1
Authors: Bowen R. A. , Elsden R. P. , Seidel G. E.
Published: February 2025

Recently hatched bovine embryos were exposed in vitro to 1 of 4 strains of bovine herpesvirus-1 to determine whether the viruses would replicate in these embryos and, if so, what pathologic consequences would ensue. Exposure to each of the viruses resulted in embryonic infection and death, and replication of the agents was demonstrated by electron microscopy and titration of progeny virus. There were no dramatic differences between virus strains in pathogenicity or in the ultrastructural pathologic findings of infection.
Microtubular mass defect of spermatozoa in the stallion
Authors: Heath E , Aire T. , Fujiwara K.
Published: February 2025

A microtubular mass (mm) defect was found in the spermatozoa of 7 Standardbred stallions; 3 stallions were sons of the same sire. Two of these 3 stallions and 2 other stallions (for a total of 4 out of the 7 stallions) were considered subfertile when the defect was first observed. Fertility improved with time, either during the first breeding season or when a given stallion was used less frequently; however, the mm defect persisted, consisting of tortuous arrays of small abnormal microtubules visible only by transmission electron microscopy. The mm probably contained the protein tubulin as indicated by immunofluorescence. Microtubules of the mm were different from normal microtubules in being highly coiled, rather than straight, without interconnecting bridges or arms and had a 20% smaller cross-sectional diameter than did normal microtubules. Synthesis of the mm may occur near areas of the nuclear membranes normally associated with the manchette of the developing spermatid.
An Alcaligenes faecalis isolate from turkeys: Pathogenicity in selected avian and mammalian species
Authors: Marshall Dana R. , Simmons D. G. , Gray J. G.
Published: February 2025

An Alcaligenes faecalis isolate of known pathogenicity for turkeys was examined for adherence and cytotoxicity in tracheal organ cultures of turkeys, chickens, Japanese quail, guinea pigs, hamsters, and mice, and for colonization and pathogenicity in these 6 species. Adherence and colonization were detected by fluorescent antibody staining. Infected and noninfected tracheal rings were examined by phase-contrast microscopy for cytotoxicity (ciliostasis, blebing of the cell membrane, and sloughing of the ciliated epithelium). Alcaligenes faecalis adhered to the tracheal rings of all species examined. Cytotoxicity was apparent in the tracheal rings of turkeys, quail, and chickens. Cytotoxicity was not detected in tracheal rings from the mammalian species. Alcaligenes faecalis colonization of turbinates and tracheas of intact turkeys and quail was detected. Clinical signs of alcaligenes rhinotracheitis were observed and histopathologic characteristics of the disease were detected. Chickens, guinea pigs, hamsters, and mice were refractory to infection with this isolate of A faecalis.
Corynebacterium pseudotuberculosis exotoxin; Fatal hemolytic anemia induced in gnotobiotic neonatal small ruminants by parenteral administration of preparations containing exotoxin
Authors: Hsu Tsuey-Ying , Renshaw Harland W. , Livingston Charles W. , Augustine John L. , Zink Donald L. , Gauer Betty B.
Published: February 2025

Inoculation of live Corynebacterium pseudotuberculosis, culture supernatant, ammonium sulfate fractionated crude exotoxin, or chromatographically purified exotoxin preparations into gnotobiotic small ruminants (n = 13) caused death of the ruminants within 48 hours. Characteristic changes observed in animals living ≥ 2 hours after inoculation included hemorrhage and edema at the site of injection, severe hemolytic anemia and hemoglobinuria, dark red fluid in body cavities, lung edema, and icterus. The crude exotoxin preparation caused a syndrome of acute shock in 2 lambs that died within 15 minutes after inoculation. Clinical and pathologic responses of animals inoculated with culture supernatant and purified toxin were similar. Histopathologic evidence indicated that the exotoxin caused necrotic changes in the proximal convoluted tubules of the kidneys. Inoculation with live organisms caused multiple foci of suppurative inflammation in skeletal muscle and adjacent adipose tissue, whereas such changes were not observed in animals administered exotoxin preparations. Although C pseudotuberculosis exotoxin induced a hemolytic anemia in the experimental animals, it did not lead to in vitro lysis of ovine, caprine, or bovine erythrocytes, unless they had been sensitized with Rhodococcus (Corynebacterium) equi filtrate.

The toxic sphingomyelin-specific phospholipase D from C pseudotuberculosis had a molecular weight of 31,000 daltons and an isoelectric point of approximately 9.6. The elution profile of exotoxin on a carboxymethyl Sephadex column was studied and the majority of the enzymatic activity was eluted by a NaCl gradient (0.2.5 M to 0.7M) with a maximum at 0.35M NaCl. Corynebacterium pseudotuberculosis exotoxin may have several biological activities; Lethality for some animals including gnotobiotic small ruminants, partial hemolysin activity in vitro and hemolysis in vivo, staphylococcal β hemolysin inhibition, potentiation of staphylococcal E lysin, vascular permeability promoting factor, and necrotizing potential for some tissues.
Efficacy of the API Staph-Ident system for identification of Staphylococcus species from milk
Authors: Jasper D. E. , M F. Infante , Dellinger J. D.
Published: February 2025

A total of 524 staphylococcal isolates from bovine milk were identified, using the API Staph-Ident system and conventional biochemical methods. The API Staph-Ident system correctly identified 192 of 201 (95.5%) Staphylococcus aureus isolates, but was correct on only 23 of 323 (7.1%) non-S aureus isolates.
Observations of fracture of the anconeal process of the ulna of swine
Authors: Kincaid S. A. , Lidvall E. R.
Published: February 2025

Fractures of the anconeal process of 5 pigs ranging in age from 4 to 8 months were studied radiographically and histologically. Clinically, animals with a fracture of the anconeal process had a “tight,” restricted gait. In pigs at 4.5 months of age, a radiolucent line through the base of the anconeal process was composed of fibrocartilage, fibrous connective tissue, and hyaline cartilage. Subperiosteal proliferation of woven bone was located along the cranial surface of the olecranon, adjacent to the base of the anconeal process. In older animals, the radiolucent line through the anconeal process contained variable amounts of fibrous connective tissue and fibrocartilage. The proliferation of subperiosteal bone at the base of the anconeal process formed a “buttress callus” which retained a radiolucent area between the callus and the proximal surface of the anconeal process. The latter region of radiolucency was continuous with the transversely oriented line that traversed the base of the anconeal process.
Abnormal canine triiodothyronine-binding factor characterized as a possible triiodothyronine autoantibody
Authors: Young Diane W. , Sartin James L. , Kemppainen Robert J.
Published: February 2025

Of more than 6,000 canine serum samples submitted to the Endocrine Diagnostic Laboratory of the School of Veterinary Medicine, Auburn University, Ala, for thyroid evaluation in 1983, 18 contained an abnormal triiodothyronine (T3)-binding factor (T3BF). These samples were easily distinguished from non-T3BF containing samples because the factor interfered with the radioimmunoassay for total T3 resulting in a profound increase in apparent values for T3 concentration. Most of the T3BF-containing samples did not have unusual thyroxine binding or inappropriate thyroxine concentrations.

Triiodothyronine binding in samples containing T3BF was inhibited by addition of exogenous T3 and was, with one exception, not affected by the addition of 8-anilino-1-naphthalene sulfonic acid (ans). Apparent affinity constants determined by Scatchard analysis were considerably greater than those of circulating T3-binding proteins found in human beings, but were similar to values obtained for human T3 autoantibodies.

After the addition and incubation of [125I] T3 with T3BF-containing samples, a large fraction of the radioactivity bound by T3BF could be precipitated by the addition of goat antibody to dog immunoglobulin G. Additional observations that the binding was insensitive to inhibition by ans, was resistant to heat inactivation, and had a high apparent affinity constant for T3 were consistent with the idea that the factor was an autoantibody to T3.
Correlation of noninvasive surface temperature measurement with rectal temperature in swine
Authors: Zinn Kurt R. , Zinn Gene M. , Jesse George W. , Mayes Herman F. , Ellersieck Mark R.
Published: February 2025

Skin and rectal temperature measurements were taken on 15 crossbred sows and gilts (225 kg) during the last 5 days of prepartum period and compared with those recorded in the first 8 days after parturition. The correlation of skin and rectal temperature values was not good during either period, although an increased correlation was noted in the postparturient period. The rectal temperature significantly (P < 0.05) increased in the postparturient period, but the mean surface temperature was unchanged. This would indicate a decreased blood flow to the surface, since an equivalent blood flow to the surface after a rectal temperature increase would result in a concomitant mean surface temperature increase. The decreased flow to the surface of the animal was selective, since a significant (P < 0.05) decrease in surface temperature was noted at the tailhead, perineum, vulva, mammae-caudal, and eye, whereas the surface temperature of the mammae-cranial and mammae-middle was significantly (P < 0.05) increased.
Comparison of the commercial agar-gel immunodiffusion test and radioimmunoprecipitation assay for detection of antibodies to bovine leukemia virus
Authors: Jacobsen Karen L. , Kaneene John B. , Miller Janice M. , Bull Robert W.
Published: February 2025

In a double-blind study, the commercial agar-gel immunodiffusion test (agid) was compared with a radioimmunoprecipitation assay (ria) performed with glycoprotein (gp) antigen for detection of antibodies to bovine leukemia virus. Of 240 sera tested, 115 were from adult cows and 125 were from precolostral calves. Most adult animals were tested within 1 week of parturition.

Sera from 74 cattle were positive and sera from 166 cattle were negative by gp ria. Sensitivity of the agid, compared with the gp ria, was 85.1% when the test was read at 48 hours and was 94.6% when read at 72 hours. Specificity increased from 92.2% at 48 hours to 96.4% at 72 hours. Reading the agid again at 72 hours also clarified most reactions that were questionable at 48 hours due to a haze around the test serum well.

Of 3 ria-positive precolostral calf sera, 2 were agid-negative and 1 had a questionable reaction by the agid at 48 hours. Of 5 ria-positive sera that were agid-negative at 48 hours, 2 were precolostral calves and 3 were cows tested at parturition. Of 166 ria-negative reactions, none was falsely positive by the agid at 48 or at 72 hours.
Effect of primary and recurrent infectious bovine rhinotracheitis virus infection on the bovine ovary
Authors: Miller J. M. , Van Der Maaten M. J.
Published: February 2025

Six heifers were inoculated iv at estrus with the Iowa or Colorado isolates of infectious bovine rhinotracheitis virus (ibrv). Subsequent measurements of plasma progesterone indicated that corpus luteum function was depressed in all heifers. In the 1st estrous cycle after inoculation, progesterone values did not exceed 2 ng/ml in 3 heifers given the Iowa isolate. Although maximal progesterone values were ≥ 2 ng/ml in 3 heifers given the Colorado isolate, values were lower than those in later cycles. Five heifers had maximal diestrual progesterone values ≥ 5 ng/ml within 5 weeks after inoculation, but in the 6th heifer, this amount of progesterone was not present until 8 weeks after inoculation.

Three to 5 months after inoculation, all heifers were given 5 daily injections of dexamethasone, 2 heifers each during metestrus, diestrus, or proestrus. Subsequent recrudescence of ibrv was demonstrated in all heifers by the isolation of virus from vaginal or nasal swab samples. The heifers were killed 10 to 17 days after initiation of dexamethasone treatment and their reproductive organs were examined for lesions and ibrv. Lesions were not seen, and ibrv was isolated only from the corpus luteum of a heifer given dexamethasone during diestrus.
Contractile responses to histamine of isolated pulmonary artery strips from healthy and heartworm-infected dogs
Authors: O'Malley Nancy A. , Venugopalan Changaram S. , Crawford M. Patrick
Published: February 2025

Pulmonary artery strips from control and Dirofilaria immitis-infected dogs were tested for isometric contractile response to histamine, carbamylcholine, and norepinephrine. The strips from D immitis-positive dogs showed diminished response to histamine; a smaller percentage of the strips contracted, and the magnitude of the contraction was less than the response of the control strips to the highest concentration used. Carbamylcholine caused virtually no contractile effect in either group. Norepinephrine contracted all strips, even those not responding to histamine. A role for histamine in the pathogenesis of the pulmonary arterial lesions associated with dirofilariasis is presented.
Effects of experimentally induced Isospora suis infection on morbidity, mortality, and weight gains in nursing pigs
Authors: Lindsay David S. , Current William L. , Taylor Julie R.
Published: February 2025

Forty-nine pigs from 6 litters were inoculated at 3 days of age with 300,000 sporulated oocysts of Isospora suis to determine the effects of neonatal coccidiosis on morbidity, mortality, and weight gain in nursing pigs. Fifty-one control pigs from 6 litters were not inoculated. Three to 5 days after inoculation, the inoculated pigs developed a nonhemorrhagic diarrhea, generally lasting 6 to 10 days, that lead to visible dehydration, loss of condition, and 20.4% mortality. Control pigs did not die or develop coccidiosis during the 3-week study and had significantly (P < 0.05) greater body weights at 7, 14, and 21 days of age than did the inoculated pigs.
Technique for percutaneous pulmonary arterial catheterization in conscious dogs
Authors: Henderson R. A. , Dillon A. R. , Brawner W. R. , Wilson S. G. , Hanrahan L. A.
Published: February 2025

A technique was developed to allow percutaneous placement and exchange of pulmonary arterial catheters in conscious dogs. Seven dogs were catheterized weekly for 5 weeks, using a 10-gauge over-the-needle cannula. A No. 7 F flow-directed catheter was passed through the cannula to measure right heart and pulmonary arterial pressures and to calculate cardiac output. The flow-directed catheter was removed and replaced with an arteriographie catheter, and a pulmonary arteriogram was performed. Placement in alternate jugular or saphenous veins each week resulted in successful catheterizations in all dogs evaluated.
Changes in urea nitrogen and creatinine concentrations in the vitreous humor of cattle after death
Authors: Lane V. M. , Lincoln S. D.
Published: February 2025

The mean urea nitrogen concentration in vitreous humor (vun) in 97 healthy steers after death was 15.7 mg/dl. The mean serum urea nitrogen concentration in the same cattle was 20.0 mg/dl. The mean vitreous creatinine (vc) concentration was 0.7 mg/dl, and the serum creatinine value was 1.5 mg/dl. The vun and vc were both significantly lower than serum urea nitrogen and serum creatinine, respectively, but varied in a consistent, predictable manner.

In tests with 10 cows, postmortem intervals as long as 36 hours and ambient temperatures up to 30 C had no significant effects on vun and vc.

Evaluation of 8 animals with uremia confirmed that the vitreous humor is a stable fluid compartment after death, usable as an indicator of serum urea nitrogen and creatinine.
Dexamethasone-induced recrudescence of malignant catarrhal fever and associated lymphosarcoma and granulomatous disease in a Formosan sika deer (Cervus nippon taiouanus)
Authors: Heusckele Werner P. , Nielsen N. O. , Oosterhuis James E. , Castro Anthony E.
Published: February 2025

Malignant catarrhal fever (mcf) was diagnosed in a 2-week-old Formosan sika deer. The fawn had been previously exposed to a clinically normal neonatal wildebeest calf from which alcelaphine herpesvirus-1 was isolated. Alcelaphine herpesvirus-1 was isolated from buffy coat leukocytes and nasal and ocular secretions of the fawn during the acute illness. The fawn clinically recovered after 3 weeks. Virus was not recovered from blood at this time. Dexamethasone, given 4 months after clinical recovery, resulted in reisolation of mcf virus from blood and recrudescence of clinical mcf. The deer was euthanatized. At necropsy, pathognomonic lesions of mcf, granulomatous disease, and malignant lymphoma were observed. Antibodies to bovine leukosis viral antigens were not detected in the serum. The epidemiologic and pathogenetic importance of the findings are discussed.
Pharmacokinetics of small doses of 3-methylindole given to horses
Authors: Thomas D. E. , Beadle R. E.
Published: February 2025

The pharmacokinetics of 3-methylindole (3MI) given orally in 2 doses (10 mg/kg and 20 mg/kg) to horses were determined.

The pharmacokinetic plasma-concentration profiles for 3MI (10- and 20-mg/kg dosages) in horses were represented by a 2-compartment open model with first-order absorption, as determined by nonlinear least-squares regression analysis. Absorption of 3MI at both dosages was rapid. Comparisons of the peak plasma concentrations, the postdistribution half lives, total clearances, and areas under the curve of the plasma-concentration profiles between the 10- and the 20-mg/kg dosages may indicate the presence of nonlinear or dose-dependent kinetics for 3MI in horses.
Susceptibility of male white-tailed deer (Odocoileus virginianus) to Brucella ovis infection
Authors: Barron S. J. , Kocan A. A. , Morton R. J. , Thedford T. R. , McCain C. S.
Published: February 2025

Infection with Brucella ovis was established by conjunctival instillation in 8 male white-tailed deer (Odocoileus virginianus). Infection was transient in young bucks, but persisted in bucks that were mature when inoculated. The deer were euthanatized and necropsied at various intervals after inoculation. Brucella ovis was recovered from a mature buck at necropsy on postinoculation day 429. Four deer had gross lesions and histopathologic changes of the epididymides. A mature noninfected buck confined for 7 months with an infected buck acquired infection and developed epididymal lesions.
Brain stem auditory-evoked responses in the dog
Authors: Bodenhamer Robert D. , Hunter Jon F. , Luttgen Patricia J.
Published: February 2025

Brain stem auditory-evoked responses (baer) were recorded from 58 dogs that did not have a known history of hearing problems. The baer wave forms had an overall mean amplitude approximately 3.0 µV and typically consisted of a series of 4 to 5 vertex-positive peaks (peaks I through V). When acoustic clicks having intensities of 60-dB hearing level (decibels relative to the subjective hearing threshold) were used as stimuli, peak I had a latency of 1.49 ± 0.13 ms; peak II, 2.32 ± 0.14 ms; peak III, 3.01 ± 0.25 ms; peak IV, 4.22 ± 0.27 ms; and peak V, 5.55 ± 0.37 ms. Latency values were influenced by a number of nonpathologic factors, including stimulus intensity and the body temperature of the dog. As stimulus intensity was decreased, there was a lengthening of the latency of each peak coupled with a decrease in the overall amplitude of baer. Decreases in rectal temperature caused a similar lengthening of peak latencies. Age may have an influence on baer, but under the conditions of the present study, the effect was not significant.
Normal and paradoxical ventricular septal motion in the dog
Authors: DeMadron Eric , Bonagura John D. , O'Grady Michael R.
Published: February 2025

Normal and paradoxical ventricular septal motions were studied in dogs, using M-mode and 2-dimensional echocardiography. Normal ventricular septal motion was evaluated, using 35 clinically healthy dogs (group I), and was compared with characteristics of septal motion measured in 12 dogs with right ventricular overload (group II) and 14 dogs with left-sided heart disease (group III). Normal ventricular septal motion consisted of a series of active and passive anterior (right cranial) and posterior (left caudal) movements that were subjectively evaluated and quantitated during segments of the cardiac cycle. Maximum excursion of the ventricular septum occurred during systole, was directed toward the left ventricle, and was related to body size. Determination of a normalized radius of septal curvature from analysis of 2-dimensional echocardiogram indicated that the septal arc formed part of a generally circular left ventricle in group I dogs. In contrast to these findings, group II dogs with right ventricular pressure and volume overloads exhibited reduced systolic septal excursion, diminished or flat septal motion, and paradoxical systolic septal motion. Normalized radius of septal curvature was significantly greater in group II dogs than in group I or group III dogs. Septal motion and radius of septal curvature in dogs comprising group III were not significantly different from normal during most phases of the cardiac cycle. Results of this study support the concept that septal motion is a reflection of overall left ventricular shape and that abnormalities in ventricular septal motion, namely flat or paradoxical septal motion, should cause the clinician to suspect right ventricular volume or pressure overload.
Familial canine dermatomyositis: Clinical, electrodiagnostic, and genetic studies
Authors: Haupt Kirk H. , Prieur David J. , Moore Michael P. , Hargis Ann M. , Hegreberg Gerald A. , Gavin Patrick R. , Johnson R. S.
Published: February 2025

Three Collies with a skin disorder, 6 progeny from a breeding of 2 of the Collies (incross litter), and the 4 progeny from the breeding of an affected Collie male and a normal Labrador Retriever female (outcross litter) were examined. By 7 to 11 weeks of age, all 6 dogs in the incross litter developed a qualitatively similar, but variably severe, dermatitis of the ears, face, lips, tip of the tail, and over bony prominences of limbs, Later, myopathic signs characterized by bilaterally symmetrical skeletal muscle atrophy of the head, neck, trunk, and extremities; facial palsy; decreased jaw tone; stiff gait; and hyperreflexia were observed in the dogs more severely affected by the dermatitis. Of the 4 dogs in the outcross litter, 3 had similar, but milder, clinical manifestations of the dermatitis and myopathy.

Cutaneous lesions consisted of intraepidermal and subepidermal vesicles or pustules with intradermal infiltration by leukocytes. Muscle lesions included myositis; myofiber degeneration, regeneration, and atrophy; and fibrosis. A generalized myopathy in the severely affected dogs was indicated by abnormal readings on needle electromyograms and normal motor nerve conduction velocities. Spontaneous needle electromyogram abnormalities were fibrillation potentials, positive sharp waves, and bizarre high-frequency discharges. Retrospective and prospective genetic analyses disclosed a definite familial tendency and indicated the condition has an autosomal dominant component.
Phagocytic and killing capacities of uterine-derived polymorphonuclear leukocytes from mares resistant and susceptible to chronic endometritis
Authors: Cheung Anthony T. W. , Liu Irwin K. M. , Walsh Erin M. , Miller Michael E.
Published: February 2025

The host defense competence of uterine-derived polymorphonuclear leukocytes (pmn) from mares considered resistant (grade I uteri) and susceptible (grade III uteri) to chronic endometritis was evaluated for phagocytic and killing (bactericidal) capacities, using a fluorochrome assay. Peripheral blood pmn from noncategorized mares and from grade I and grade III mares were used as controls.

Uterine-derived pmn from mares with grade I uteri were functionally competent for phagocytosis and killing of Candida albicans, whereas uterine-derived pmn from mares with grade III uteri had significantly less phagocytic and killing capacities (P ≥ 0.0001).

Results of the present study, together with data obtained from chemotactic responsiveness and deformability assays of a previous study, indicated an overall deficiency in the host defense mechanism of uterine-derived pmn from mares with grade III uteri obtained 12 hours after induced Streptococcus zooepidemicus infection. This deficiency may account for the susceptibility of mares with grade III uteri to chronic endometritis.
Visceral analgesia: Effects of xylazine, butorphanol, meperidine, and pentazocine in horses
Authors: Muir W. W. , Robertson J. T.
Published: February 2025

The visceral analgesic, cardiorespiratory, and behavioral effects induced by xylazine, butorphanol, meperidine, and pentazocine were determined in 9 adult horses with colic. Colic was produced by inflating a balloon in the horses' cecum. Heart rate, respiratory rate, mean arterial blood pressure, and cardiac output increased after cecal balloon inflation. Xylazine and butorphanol decreased the hemodynamic response to cecal balloon inflation. Meperidine and pentazocine had minimal effects on the cardiorespiratory changes induced by cecal balloon inflation. Xylazine produced the most pronounced visceral analgesia. The duration of visceral analgesia was longest with xylazine (approx 90 minutes) followed by butorphanol (approx 60 min) and then by meperidine and pentazocine (approx 30 to 35 min). Accurate assessment of the effects of visceral analgesics is dependent upon the use of objective tests to evaluate pain.
Pharmacokinetics and bioavailability of cephalothin in horse mares
Authors: Ruoff W. W. , Sams R. A.
Published: February 2025

The pharmacokinetics and bioavailability of cephalothin given to 6 horse mares at a dosage level of 11 mg/kg of body weight iv or im were investigated. The disposition of cephalothin given iv was characterized by a rapid disposition phase with a mean half-life of 2.89 minutes and a subsequent slower elimination phase with a mean half-life of only 14.7 minutes. The mean residence time of cephalothin was 10.6 ± 2.11 minutes. The total plasma clearance of cephalothin averaged 13.6 ml/mm/kg and was caused by metabolism and renal elimination. Renal clearance of cephalothin averaged 1.32 ml/min/kg and accounted for elimination of about 10.1% of the administered dose. The volume of distribution at steady state averaged 151 mg/kg. Plasma protein binding of cephalothin at a concentration of 10 µg/ml averaged 17.9 ± 2.5%.

Cephalothin was rapidly metabolized to desacetytcephalothin. Maximum plasma desacetylcephalothin concentrations were observed in the blood samples collected 5 minutes after iv doses and averaged 22.9 µg/ml. The apparent half-life of desacetylcephalothin in plasma was 41.6 minutes and its renal clearance averaged 4.49 ± 2.43 ml/min/kg. An average of 33.9% of the dose was recovered in the urine as desacetylcephalothin.

The maximum plasma cephalothin concentration after im administration was 11.3 ± 3.71 µg/ml. The terminal half-life was 47.0 minutes and was longer than the half-life after iv administration. The bioavailability of cephalothin given im ranged from 38.3% to 93.1% and averaged 65.0 ± 20.5%,
Campylobacter sputorum subsp mucosalis and Campylobacter hyointestinalis infections in the intestine of gnotobiotic pigs
Authors: Boosinger Timothy R. , Thacker H. Leon , Armstrong Charles H.
Published: February 2025

At 4 days of age, 7 gnotobiotic pigs were orally inoculated with broth cultures of both Campylobacter sputorum subsp mucosalis (csm) and Campylobacter hyointestinalis (ch). One pig was killed and evaluated each week for 7 weeks. Forty-eight hours after inoculation, ch and csm were recovered from the feces of the pigs; thereafter, only ch was recovered. Organisms morphologically typical of Campylobacter sp were observed on the mucosal surface and on the crypt epithelial cells of the ileum, cecum, and colon from post-inoculation weeks (piw) 2 through 7.

Bacteria were clustered around the surface opening of goblet cells in pigs at piw 6 and 7. Crypt epithelial cell proliferation and intracellular bacteria were not seen, except in 1 pig (killed at piw 7) in which intracellular bacteria were seen only in the cecum. Therefore, csm and ch did not induce porcine proliferative enteritis in gnotobiotic pigs.
Effect of intrauterine infusion of Escherichia coli endotoxin in postpartum pony mares
Authors: Blanchard T. L. , Elmore R. G. , Kinden D. A. , Berg J. N. , Mollett T. A. , Garcia M. C.
Published: February 2025

Fifteen pony mares were assigned to 1 of 3 treatment groups after foaling: Group 1, 35 ml of sterile saline solution was infused into the uterine lumen within 24 hours after parturition (6 mares); group 2, 300 mg of Escherichia coli endotoxin was infused into the uterine lumen within 24 hours after parturition (6 mares); and group 3, 300 mg of E coli endotoxin was infused into the uterine lumen between 72 and 96 hours after parturition (3 mares). Rectal temperatures were taken at −1, −0.5, 0, 0.5, 1, 1.5, 2, 3, 4, and 5 hours after treatment. Venous blood samples were also taken at these times for routine wbc counts. Data were analyzed as a repeated measurement design with linear and quadratic orthogonal contrasts performed where significant time and interaction with time occurred. Pretreatment averages of total wbc and neutrophil counts were compared with their nadir posttreatment averages by a t test when treatment-by-time interaction was significant for the parameter.

Rectal temperature (37.9 ± 0.1 C) remained stable and did not vary among treatment groups after intrauterine infusions. In contrast, total wbc and neutrophil counts did vary among treatment groups across time. However, for treatment groups 1 and 3, neither blood total wbc count nor neutrophil count after intrauterine infusions was different from pretreatment observations. In group 2, total wbc count decreased (P < 0.10) from a pretreatment average of 11.5 ± 0.4 × 103 cells/mm3 to a nadir concentration of 10.0 ± 0.6 × 103 cells/mm3 by 60 minutes after infusion of endotoxin into the uterus. Blood neutrophil count in group 2 decreased (P < 0.025) from a pretreatment average of 7.4 ± 0.4 × 103 cells/mm3 to 5.4 ± 0.6 × 103 cells/mm3 by 2 hours after treatment.

Endometrial biopsy samples were taken from 3 mares in each treatment group after the last blood samples were obtained. Biopsy samples were examined by scanning electron microscopy. The mucosal surfaces of endometria from all treatment groups remained intact and appeared cytologically normal with no indication of cellular damage or injury.
Efficacy of the tris-salt of 2[(methoxycarbonylamino)-[2-nitro-5-(n-propylthio) phenylimimo] methylamino] ethane sulfonic acid against inhibited larvae of Ostertagia ostertagi
Authors: Williams J. C. , Knox J. W. , Marbury K. S. , Kimball M. D. , Willis Ε. R. , Snider T. G. , Miller J. E.
Published: February 2025

The tris-salt of 2-[(methoxycarbonylamino) - [2-nitro-5-(n-propylthio) phenylimimo] methylamino] ethane sulfonic acid (mca) was evaluated against naturally acquired gastrointestinal parasitism in cattle during spring in Louisiana to determine efficacy of the compound against inhibited early 4th-stage larvae (EL4) of Ostertagia ostertagi. Forty-three crossbred yearling beef heifers were grazed together on contaminated pastures between Mar 1 and Apr 18, 1984. On April 17, 3 of the 43 heifers were slaughtered. Analysis of worm population characteristics in the 3 cattle indicated sufficient numbers of Ο ostertagi EL4, and other worm genera and species in these cattle to pursue a valid evaluation of the anthelmintic efficacy of mca. The remaining 40 heifers were removed from pasture on April 18. On April 24, they were allotted into 4 treatment groups (10/group) based on an equal distribution of body weights and on whether they were spring- or autumn-born cattle. On April 25, the cattle were treated as follows: group 1, nontreated controls; group 2, treated with mca at 7.5 mg/kg of body weight by oral drench; group 3, treated with mca at 15.0 mg/kg by oral drench; and group 4, treated with mca at 20.0 mg/kg by oral drench. The cattle were then confined in drylot pens until May 7. Similar numbers of cattle from each group were killed over a 3-day period from May 8 to May 10 (13 to 15 days after treatment). Mean numbers of Ο ostertagi recovered from nontreated controls were: adults, 8,279; developing 4th-stage larvae, 2,806; and inhibited EL4, 12,070. The mean percentage inhibition was 51.2%. Means for significant numbers of other parasite genera recovered from nontreated controls were: Trichostrongylus axei adults, 42,260; immature, 1,118; Haemonchus sp adults, 979; and Cooperia spp adults, 588. Percentage reduction of parasites at the 7.5, 15.0, and 20.0 mg/kg dosages were, respectively: Ο ostertagi adults, 94.9, 98.7, and 99.2; developing 4th-stage larvae, 83.3, 86.8, and 91.0; inhibited EL.,, 60.2, 74.7, and 81.5; T axei adults, 99.7, 99.9, and 99.8; immature, 100.0, 100.0, and 100.0; Haemonchus sp adults, 95.1, 100.0, and 100.0; and Cooperia spp adults, 89.5, 98.3, and 96.6. Variability of efficacy against Ο ostertagi-inhibited EL4 was observed at all dosages.