bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors associated with circulation of pseudorabies virus within swine herds
Authors: Anderson Paul L. , Morrison Robert B. , Molitor Thomas W. , Thawley David G.
Published: December 2023

Data were collected from 104 Minnesota swine farms quarantined for pseudorabies virus (prv) infection. Each herd was serologically evaluated for the presence of antibodies to prv in finishing pigs. Herd management practices, swine housing design, and disease profiles were described for each farm. Multiple logistic regression analysis was used to determine which factors were associated with circulation of prv in the finishing pigs of farrow-to-finish farms. Sixty-seven (64%) of the herds had no serologic evidence of prv circulation in the finishing section, whereas 37 herds (36%) contained at least one prv seropositive finishing pig. The odds of a given finishing herd being seropositive for prv were 2.85 times higher if the finishing pigs were housed in confinement (P = 0.01), 2 times higher if Actinobacillus (Haemophilus) pleuropneumoniae was a clinical problem in the herd (P = 0.03), 1.36 times less for each year that passed since the herd quarantine was issued (P = 0.01), 1.74 times higher if clinical signs of prv were reported (P = 0.04), and 1.52 times higher if animal protein was included in at least one of the rations (P = 0.08).
Bradycardia in cattle deprived of food
Authors: McGuirk Sheila M. , Bednarski Richard M. , Clayton Murray K.
Published: December 2023

Bradycardia was documented in 12 cattle from which food had been withheld for 48 hours in preparation for general anesthesia and an elective surgical procedure. The heart rates decreased by a mean of 14 beats/min, and 4 cows had sinus arrhythmia. To evaluate this finding, the heart rates of 21 clinically normal cattle were evaluated before and after food was withheld for 48 hours. Bradycardia developed in all of the clinically normal cattle, with the mean decrease in heart rate being 23 beats/min. Five of the clinically normal cows developed sinus arrhythmia. It was concluded that bradycardia and sinus arrhythmia in cattle are associated with deprivation of food.
Use of transcolonic 99mtechnetium-pertechnetate as a screening test for portosystemic shunts in dogs
Authors: Koblik Philip D. , Komtebedde J. , Yen C-K , Hornof W. J.
Published: December 2023

99mTechnetium-pertechnetate, when administered in high concentration into the colon, is rapidly absorbed across the colonic mucosa and results in a nuclear angiogram of the portal circulation. In normal dogs, a series of dynamic lateral scintigraphic images of the abdomen resulted in sequential visualization of the portal vein, liver, and several seconds later, the heart and lungs. In contrast, studies performed in 9 dogs with surgically confirmed portosystemic shunts demonstrated a different pattern of distribution, with heart and lung activity occurring before liver activity. In several cases, the aberrant shunt vessels could be identified. Studies were easy to perform, were well tolerated, and required no computer processing for interpretation.
Efficacies of erythromycin and chloramphenicol in extinguishing fecal shedding of Campylobacter jejuni in dogs
Authors: Monfort J. Daniel , Donahoe John P. , Stills Harold F. , Bech-Nielsen Steen
Published: December 2023

Oral treatment regimens of erythromycin stearate and chloramphenicol were evaluated in naturally infected laboratory colony dogs for their efficacies in extinguishing fecal shedding of Campylobacter jejuni. Of the 25 Campylobacter-infected English Foxhounds in the study, 9 were assigned to erythromycin treatment, 9 to chloramphenicol treatment, and 7 to no treatment. Antimicrobials were administered for 12 days. All of the dogs that received erythromycin stearate ceased shedding C jejuni by the fourth day of treatment and remained negative throughout the treatment period. Chloramphenicol was associated with a reduction in shedding from 100% to 57% by the ninth day of treatment. Within 9 days of the discontinuation of antimicrobial treatment, C jejuni was isolated from all chloramphenicol-treated dogs and 89% erythromycin-treated dogs.
Mycoplasmal mastitis in a dairy herd
Authors: Brown M. B. , Shearer J. K. , Elvinger F.
Published: December 2023

In October 1985, mycoplasmas were isolated from bulk tank milk samples in a large Florida dairy (>1,400 lactating cows). At that time, measures to isolate and control the spread of infection were instituted. In an initial screening test, Mycoplasma bovis was isolated from 21 of 153 milking string samples (milk from all quarters of 10 cows/string). Composite quarter milk samples from all quarters of every individual lactating cow in the herd were obtained for culture in November 1985 and December 1985. In October, 88 of 1,535 (5.7%) cows were identified as Mycoplasma-positive. An additional 31 Mycoplasma-infected cows were identified in December. The dairy elected to maintain the infected cows in a separate Mycoplasma-positive subherd, which would be milked at the end of each milking session. Seven additional Mycoplasma-positive cows were identified at initiation of lactation. All newly identified infected cows were transferred to the Mycoplasma-positive subherd. After segregation of Mycoplasma-positive cows, bulk tank milk samples obtained routinely from the main herd remained culture negative throughout the study. From February 1986 to October 1986, quarter milk samples were obtained monthly from cows in the Mycoplasma-positive subherd. Any cow that developed clinical mastitis or substantial decrease in milk production was, at the discretion of the herdsman, culled. Of the 126 cows in the subherd, 22 (17.5%) were culled for mastitis, 35 (27.8%) were culled for low production, and 9 (7.1%) were culled for other reasons. Of the remaining 60 cows, 16 (12.7% of the 126 cows) were Mycoplasma-positive on the basis of results from one or more samples obtained after February 1986. Significant differences were not observed in milk production between Mycoplasma-positive cows remaining in the subherd and uninfected control cows in the main herd. Cows culled for low milk production had significantly (P < 0.001) lower milk production than did cows of other groups. Cows culled for mastitis were more frequently in second lactation (P = 0.04).
Circumocular pigmentation and incidence of ocular squamous cell tumors in Bos taurus and Bos indicus × Bos taurus cattle
Authors: Bailey Curtiss M. , Hanks Donald R. , Hanks M.A.
Published: December 2023

Amount of circumocular pigmentation and incidence of ocular squamous cell tumors were evaluated in dams representing diverse cattle breed types. Each dam was examined twice annually during a specific stage in the life cycle (3.5 to 9.5 years old). Overall, 28.3% of dams in the herd developed at least 1 ocular squamous cell tumor. Breed groups differed (P < 0.01) in amount of circumocular pigmentation and incidence of tumors. Results indicate that losses from ocular squamous cell tumors in beef herds can be sharply reduced by judicious choice of breed types.
Epidemiologic study of salmonellae shedding in the feces of horses and potential risk factors for development of the infection in hospitalized horses
Authors: Traub-Dargatz Josie L. , Salman Mo D. , Jones Robert L.
Published: December 2023

A study was designed to identify epidemiologic factors associated with the development and spread of salmonellae in horses in a veterinary teaching hospital, through a case-control study and a longitudinal follow-up prospective study. In the casecontrol study, 44 horses shedding salmonellae in feces were compared with 99 control horses not shedding salmonellae in feces; regarding breed, sex, age and initial diagnosis, none of the odds ratios for study factors was significant. The factors found to be associated with fecal shedding of salmonellae in the prospective study included diarrhea at the time of admission to the hospital, fever while hospitalized, and a change in diet while hospitalized. Horses identified to be shedding salmonellae in feces were not limited to those with clinical signs of salmonellosis; however, spread of salmonellae from a shedder without clinical signs of disease to other hospitalized horses was not identified. The most common serovars of Salmonella isolated were oranienburg and newport.
Drug therapy in cats: A therapeutic category approach
Authors: Boothe Dawn Merton
Published: December 2023

The third article of this 4-part series discusses drug therapy in cats by therapeutic category. Specifically, the use of drugs to control infections, pain, fever, inflammation, cancer, and selected parasites is described. In addition, the use of hormonally related drugs and selected miscellaneous drugs in cats is addressed. Drugs emphasized are those for which use in cats is frequently associated with adverse reactions or drugs for which use is limited to illnesses that tend to be unique in cats.
Clinical, pathologic, and microbiologic findings of foot abscess in neonatal pigs
Authors: Gardner Ian A. , Hird David W. , Sullivan Nadine M. , Pierce Robert J.
Published: December 2023

A longitudinal study was undertaken in a swine herd with an ever-present problem of foot abscess in suckling pigs reared on a woven-wire floor. Of 3,322 4-day-old pigs, 199 (6%) developed abscess lesions involving claws and accessory digits before weaning. Lesions were first detected in 4-day-old pigs; median and mean ages at onset were 10 and 11.3 days, respectively. At first detection, most pigs had only a single claw affected, but 39 pigs had at least 2 claws with abscesses. Hind limbs had more affected claws (140) than forelimbs (96). In the hind limbs, medial claws were most likely to have lesions, whereas the reverse was true for the forelimbs. Gross and microscopic examinations of affected claws indicated necrotic pododermatitis, with severe osteomyelitis, arthritis, and tenosynovitis. Bacteria isolated from foot abscess lesions included Actinomyces pyogenes, Staphylococcus spp, β-hemolytic Streptococcus spp, Actinobacillus spp, Escherichia coli, Fusobacterium spp, Bacteroides spp, and Peptostreptococcus spp.
Impedance cardiography by use of a spot-electrode array to track changes in cardiac output in anesthetized dogs
Authors: Kiesler T.W. , Voorhees W.D. , Wessale J.L. , Pham C.K.
Published: December 2023

Transthoracic impedance cardiography is a noninvasive method to determine changes in cardiac output on the basis of the cardiac-induced impedance change measured across the thorax. In this report, we describe a new, easily applied, tetrapolar spot-electrode configuration for use in canine transthoracic impedance cardiography. The array is a convenient alternative to use of the traditional circumferential band-electrode array which, in the dog, is prohibitive because of the extensive skin preparation required. The spot-electrode array was used to compare changes in cardiac output measured by transthoracic impedance cardiography, with changes measured by a reference indicator-dilution technique.

A spot-electrode array, composed of 4 standard ECG electrodes, was used to measure transthoracic impedance in 10 anesthetized dogs. Variations in cardiac output were produced by controlled hemorrhage (200- to 250-ml increments). Simultaneous reference measurements of cardiac output were made before hemorrhage (control) and at each level of hemorrhage, using the saline-dilution method. The beat-by-beat impedance changes were measured by use of a Minnesota impedance cardiograph, which also recorded the first derivative of impedance (dZ/dt). An index of cardiac output was defined as the product of the maximal value of the first time derivative of impedance, ejection time, and heart rate for each beat during inscription of a saline-dilution curve. The average of the beat-bybeat indices was calculated and then normalized relative to the initial control value. Linear regression analysis was performed to evaluate the correlation of the index of cardiac output with the reference cardiac output. The slope and correlation coefficient for the pooled data were 0.90 and 0.92, respectively. These results indicate that changes in cardiac output can be tracked reliably in anesthetized dogs by transthoracic impedance cardiography by use of a convenient spotelectrode configuration.
Serodiagnosis of equine monocytic ehrlichiosis in selected groups of horses in Minnesota
Authors: Olchowy Timothy W.J. , Ames Trevor R. , Molitor Thomas W.
Published: December 2023

Antibody titer to Ehrlichia risticii was determined, in 2,549 equine serum samples, using an indirect fluorescent antibody assay. During 1986, samples were obtained from the Minnesota State-Federal Equine Infectious Anemia Diagnostic Laboratory, the Minnesota Racing Laboratory, from horses admitted to the University of Minnesota Veterinary Teaching Hospital, and as a result of field investigations of horses with acute diarrhea. Results of the study revealed antibody prevalence of 33, 24, 47, and 25% for the respective groups. There was no statistical association between seropositive status and age, sex, breed, or clinical problem of horses referred to the teaching hospital. There was an increase in the total percentage of seropositive samples over the duration of the sample collection period, suggesting a seasonal exposure pattern, and E risticii was associated with clinical and subclinical infections in horses of Minnesota.
Generalized motor seizures after portosystemic shunt ligation in dogs: Five cases (1981-1988)
Authors: Matushek K. J. , Bjorling Dale , Mathews Karol
Published: December 2023

Severe generalized motor seizures developed in 5 dogs between 13 hours and 3 days after surgical attenuation of a single extrahepatic portosystemic shunt. Three dogs died, and a fourth was euthanatized because of poor prognosis for recovery. The fifth dog, although improved, was still not clinicall ynormal 15 months after surgery. An intra-orextracranial cause for the seizures could not be identified in any of these dogs. Postmortem examination results in 3 dogs were similar to findings previously reported in dogs with portosystemic shunts, but which did not undergo surgical shunt ligation. Of the 5 dogs, 4 were >18 months old, which may indicate that older dogs are more likely to develop seizures after shunt ligation than are younger dogs.
Tick parasitism and antibodies to Borrelia burgdorferi in cats
Authors: Magnarelli Louis A. , Anderson John F. , Levine Harvey R. , Levy Steven A.
Published: December 2023

Ticks were removed from naturally infested cats, and serum samples from these cats were tested for antibodies to Borrelia burgdorferi. Twenty-two of 93 cats (23.7%) had one or more motile stages of Ixodes dammini attached. Of 2 larvae and 20 nymphs removed from cats, 1 larva and 2 nymphs were infected with B burgdorferi. Spirochetes were not found in tissues of 13 female and 4 male ticks. Ten of 71 serum samples analyzed by indirect fluorescent antibody staining or elisa contained antibodies to this spirochete. Maximal antibody titers were 1:256 and 1:2,560, respectively. At titers ≥1:160 in elisa, seropositivity ranged from 8.8% (n = 34 sera tested from 34 cats) in May through July to 33.3% (n = l2 cats tested) during February through April. In clinical studies of 30 cats, there were nearly equal percentages of seropositive cats with limb or joint disorders not accompanied by fever, anorexia, or fatigue (5 of 21 cats) and cats with these signs of illness but lacking lameness (2 of 9 cats.)
Plasma cortisol response to ketoconazole administration in dogs with hyperadrenocorticism
Authors: Feldman Edward C. , Bruyette David S. , Nelson Richard W. , Farver Thomas B.
Published: December 2023

The effect of orally administered ketoconazole on plasma cortisol concentration in dogs with hyperadrenocorticism was evaluated. Every 30 minutes from 0800 hours through 1600 hours and again at 1800 hours, 2000 hours, and 0800 hours the following morning, 15 clinically normal dogs and 49 dogs with hyperadrenocorticism had plasma samples obtained and analyzed for cortisol concentration. The mean (± sd) plasma cortisol concentration for the initial 8-hour testing period was highest in 18 dogs with adrenocortical tumor (5.3 ±1.6 µg/dl), lowest in 15 control dogs (1.3 ± 0.5 µg/dl), and intermediate in 31 dogs with pituitary-dependent hyperadrenocorticism (pdh; 3.4 ± 1.2 µg/dl). Results in each of the 2 groups of dogs with hyperadrenocorticism were significantly (P < 0.05) different from results in control dogs, but not from each other. The same cortisol secretory experiment was performed, using 8 dogs with hyperadrenocorticism (5 with pdh; 3 with adrenocortical tumor) before and after administration at 0800 hours of 15 mg of ketoconazole/kg of body weight. Significant (P < 0.05) decrease in the 8-hour mean plasma cortisol concentration (0.9 ± 0.2 µg/dl) was observed, with return to baseline plasma cortisol concentration 24 hours later.

Twenty dogs with hyperadrenocorticism (11 with pdh, 9 with adrenocortical tumor) were treated with ketoconazole at a dosage of 15 mg/kg given every 12 hours for a half month to 12 months. The disease in 2 dogs with pdh failed to respond to treatment, but 18 dogs had complete resolution of clinical signs of hyperadrenocorticism and significant (P < 0.05) reduction in plasma cortisol responsiveness to exogenous adrenocorticotropin (acth). The healthy control dogs had a mean baseline plasma cortisol concentration of 1.4 ± 0.4 µg/dl and a post-acth cortisol concentration of 10.6 ± 3.1 µg/dl. Before ketoconazole administration, all 11 dogs with pdh had a mean baseline plasma cortisol concentration of 4.4 ± l.9 µg/dl and a post-acth cortisol concentration of 33.6 ± 17.6 µg/dl. The 9 dogs with adrenocortical tumor had a mean baseline plasma cortisol concentration of 4.4 ± 1.3 µg/dl and post-acth cortisol concentration of 28.1 ± 14.1 µg/dl. After 5 days of ketoconazole administration, the post-acth plasma cortisol concentration for dogs with pdh or adrenocortical tumor was 4.0 ± 5.4 µg/dl and 6.0 ± 3.3 µg/dl, respectively. Similar responses were observed after 60, 180, and 360 days of ketoconazole treatment.
Fecal proteolytic activity in clinically normal cats and in a cat with exocrine pancreatic insufficiency
Authors: Williams David A. , Reed Scott D. , Perry Lindall
Published: December 2023

Fecal proteolytic activity determined in single samples collected on each of 3 consecutive days from each of 20 clinically normal cats ranged from 19 to 363 azocasein units (acu)/g of feces when determined colorimetrically, using azocasein substrate, and ranged from undetectable (in 1 sample from 1 cat) to 21 mm of gel-clearing when determined using radial enzyme diffusion in agar gels containing a casein substrate. Corresponding mean 3-day values for each cat ranged from 29 to 207 acu/g and from 5 to 16 mm, respectively. Studies of proteolytic activity remaining after treatment of fecal extracts with a specific trypsin inhibitor indicated that trypsin accounted for 0 to 77% of proteolytic activity. In a cat with exocrine pancreatic insufficiency, fecal proteolytic activity was 0, 0, and 3 acu/g in a sample of feces collected from each of 3 consecutive days and was undetectable by use of radial enzyme diffusion. Assay of fecal proteolytic activity by use of either azocasein hydrolysis or radial enzyme diffusion allows evaluation of pancreatic function in cats, provided that several samples of feces are tested.
Effect of chewing rawhide and cereal biscuit on removal of dental calculus in dogs
Authors: Lage Arthur , Lausen Niels , Tracy Ronald , Allred Elizabeth
Published: December 2023

The effect of chewing rawhide and cereal biscuit on removal of dental calculus was studied in 67 dogs. Two methods were used to measure supragingival calculus and calculus removal as a function of time and acceptability. Trial 1 used a quantitative method based on actual measurement of the area of calculus on a tooth, and trial 2 used a quantitative method based on an arbitrary grading system to establish a supragingival calculus index. Analysis was performed, using 2-factor (trial 1) and a 3-factor (trial 2) analysis of variance.

Results indicated that dogs removed calculus from their teeth by chewing rawhide; some teeth were cleaned better than others. The optimal amount or frequency of rawhide treatment was not necessarily determined.

It was determined that regular consumption of up to 3 rawhide strips/d for 3 weeks was safe. Processed biscuits were sometimes effective in removing calculus from dog's teeth; however, biscuits were not as effective as the rawhide in removing supragingival calculus.
Treatment of glaucoma by use of transscleral neodymium:yttrium aluminum garnet laser cyclocoagulation in dogs
Authors: Nasisse Mark P. , Davidson Michael G. , English Robert V. , Jamieson Vivian , Harling David E. , Tate Lloyd P.
Published: December 2023

Neodymium:yttrium aluminum garnet (Nd:yag) laser energy was transsclerally applied to the ciliary body of 56 eyes of 37 dogs for treatment of glaucoma. Forty-four eyes were glaucomatous at the time of treatment, and 12 normotensive eyes with ciliary cleft closure were treated prophylactically. Glaucoma was primary in 35 dogs and secondary in 2 dogs (1 eye in each dog). Energy was delivered by a general surgical Nd:yag laser via a hand-held, 600-µc-diameter flexible quartz fiber. The mean (±sd) number of spots treated per eye was 35 (±9.7), with mean energy per burst of 7.1 (±2.6) J; mean total energy delivered to the eyes was 228 (±81) J.

Follow-up evaluation was available for 42 eyes from 2 to 4 weeks after treatment, and for 32 eyes from 12 to 24 weeks after treatment. Treatment success, defined as maintenance of intraocular pressure <25 mm of Hg, was achieved in 83% (20/24) of glaucomatous eyes evaluated between 12 and 24 weeks of treatment. Of 4 treatment failures, 3 were eyes devoid of uveal pigment. The consistent acute effects of treatment were conjunctival vascular congestion and blood-aqueous barrier disruption, recognized clinically by the presence of aqueous flare. Hyphema developed in 16% (9/56) of eyes; hyphema resolved without complication in all but 2 eyes. A common long-term complication of treatment was cataract formation, recognized in 37% (12/32) of eyes evaluated at 12 to 24 weeks. Cataracts were sufficiently dense to obstruct vision in 4 eyes. Phthisis bulbi was observed in 1 eye. Results of this study indicate that Nd:yag laser cyclocoagulation is an effective means of controlling intraocular pressure in dogs with glaucoma. Cataract formation is a potential complication of treatment.
Effect of Campylobacter spp–induced enteritis on growth rate and feed efficiency in pigs
Authors: Straw Barbara E.
Published: December 2023

Diarrhea caused by Campylobacter spp-induced enteritis was observed in pigs that were part of a pneumonia study. Growth rate, feed conversion, and daily health status had been recorded for each pig in the trial. Because diarrhea was the only clinical sign of disease that developed in the control group of pigs, and no other diseases were detected in these pigs at slaughter, it was possible to examine the effect of diarrhea on growth rate and feed efficiency. During the course of the study, 6 of the 16 control pigs had severe diarrhea, 2 were moderately affected, and another 8 were slightly affected or remained clinically normal. Compared with the mean values for each pig, feed intake and daily weight gain were reduced in the week preceding the appearance of clinical disease, but not during the time when diarrhea was observed. Overall performance of pigs with severe diarrhea was not different from that of pigs that were not affected.
Determination of the relationship between sperm morphologic classifications and fertility in stallions: 66 cases (1987-1988)
Authors: Jasko D. J. , Lein D. H. , Foote R. H.
Published: December 2023

The analysis of breeding records and sperm morphologic classifications from ejaculated semen during 99 stallion seasons, over a 2-year period, revealed a significant correlation (r = 0.34, P < 0.01) between the percentage of morphologically normal sperm in ejaculates and the per cycle fertility estimate of the stallions studied. In addition, the percentage of sperm classified as having major defects (abnormal heads, proximal droplets, and abnormal midpieces) was significantly inversely correlated (r = −0.36, P < 0.01) with the same fertility estimates. Multiple variable regression demonstrated that the variation in 2 morphologic features classified as major defects, abnormal heads, and proximal droplets, accounted for the largest amount of variation in fertility. It appears that in stallions, a large percentage of ejaculated sperm with major defects or other defects in combination with major defects is associated with a larger reduction in fertility than is associated with other defects.
Serum thyroid hormone concentrations in clinically normal dogs after administration of freshly reconstituted vs previously frozen and stored thyrotropin
Authors: Kobayashi Dani L. , Nichols Rhett , Peterson Mark E.
Published: December 2023

Concentrations of serum thyroxine (T4) and 3,3′ ,5-triiodothyronine (T3) were determined in 7 clinically healthy adult dogs before and after administration of freshly reconstituted thyrotropin (tsh) and tsh that had been previously reconstituted and frozen for 1, 2, and 3 months. The 4 tsh response tests were performed at 30-day intervals by collecting blood samples for serum T4 and T3 determinations before and 4 and 6 hours after iv administration of tsh (0.1 U/kg of body weight). Baseline serum concentrations of T4 and T3 were similar at each of the 4 sample collection times over the 3-month period of the study. Mean serum concentrations of T4 and T3 increased significantly (P < 0.01) over baseline values after administration of freshly reconstituted tsh or tsh that had been previously frozen for 1, 2, or 3 months. Significant difference was not found in the mean post-tsh serum T4 or T3 concentration after injection of freshly reconstituted tsh or tsh that had been previously frozen for 1, 2, or 3 months. In 2 of the 7 dogs, mild reactions—mild ataxia and weakness—were observed during the last of the series of tsh response tests (ie, after iv administration of tsh that had been previously frozen for 3 months). Results of this study suggest that for use in dogs, reconstituted tsh stored at — 20C maintains adequate biological activity for at least 3 months. The ability to store reconstituted tsh for a longer period than the recommended 48 hours represents an economic advantage, because it allows clinicians to perform more tsh response tests per vial of tsh.
Serum thyroxine concentrations following fixed-dose radioactive iodine treatment in hyperthyroid cats: 62 cases (1986-1989)
Authors: Meric Susan M. , Rubin Stanley I.
Published: December 2023

The medical records of 62 hyperthyroid cats treated with a fixed dose of 4 mCi of radioactive iodine (131I) were reviewed. In 60 cats, serum thyroxine concentrations were determined after treatment, allowing evaluation of treatment success. Eighty-four percent of the cats had normal serum thyroxine concentrations after treatment. Five of the 60 cats (8%) remained hyperthyroxinemic after treatment. Five cats (8%) were hypothyroxinemic when evaluated within 60 days of treatment. Three of these cats had normal serum thyroxine concentrations 6 months after treatment, and none had clinical signs of hypothyroidism. The administration of a fixed dose of 4 mCi of 131I was determined to be an effective treatment for feline hyperthyroidism.
Effects of sedation on intradermal skin testing in flea-allergic dogs
Authors: Beale Karin Muth , Kunkle Gail A. , Chalker Linda , Cannon Randall
Published: December 2023

Effects of 4 commonly used sedatives on the wheal-and-flare response to histamine and flea antigen were evaluated in 8 flea-allergic Beagles. Skin testing was performed on 12 separate occasions, 3 to 4 days apart. Twelve intradermal injections were given during each skin test: 5 doubling dilutions of histamine phosphate, 6 doubling dilutions of flea antigen, and a phosphate-buffered saline solution (negative control). Of the 12 intradermal skin tests, 8 were control tests performed on nonsedated dogs. The remaining 4 tests were performed on dogs sedated with xylazine, ketamine and valium combination, acepromazine, or oxymorphone. Oxymorphone had the most profound effect on skin test results, significantly (P < 0.05) decreasing skin responsiveness in 8 of 11 test sites (by objective evaluation) and in 5 of 11 test sites (by subjective evaluation). Xylazine sedation enhanced skin test results in 4 of 11 test sites (by objective evaluation) and in 1 of 11 test sites (by subjective evaluation). In no instance did xylazine significantly decrease skin responsiveness to histamine or flea antigen. Xylazine is the recommended sedative in dogs when sedation is necessary for intradermal skin testing.
Clinical and epizootiologic characteristics of dogs seropositive for Borrelia burgdorferi in Texas: 110 cases (1988)
Authors: Cohen N.D. , Carter C.N. , Thomas M.A. , Angulo A.B. , Eugster A.K.
Published: December 2023

Of 2,409 canine serum samples submitted to the Texas Veterinary Medical Diagnostic Laboratory between Jan 1, 1988 and Dec 31, 1988 and tested by immunofluorescent antibody technique for antibody to Borrelia borgdorferi, 132 (5.5%) had positive results. Clinical and epizootiologic characteristics of seropositive dogs from Texas (n = 110) were examined. Male dogs were more likely than female dogs to be seropositive for B burgdorferi. The most frequent clinical sign of disease described in seropositive dogs was lameness; neurologic, ophthalmologic, dermatologic, renal, and hepatic signs also were reported by referring veterinarians.
Considerations for use of descriptive epidemiology to investigate fetal loss in dairy cows
Authors: Thurmond M. C. , Picanso J. P. , Jameson C. M.
Published: December 2023

Various descriptive approaches were taken in a prospective investigation to characterize fetal loss in cows on a California dairy. The methods and observations were offered for consideration by practitioners engaged in dairy herd health medicine. For 4,732 pregnancies followed from 2,163 cows in a 6.5 year period, the respective proportions (percentage) of cows aborting (1 – cumulative proportion not aborting by 260 days) and abortion densities (abortions per 10,000 cow-days-at-risk) were 10.63 and 6.29 for all fetal deaths, 9.36 and 5.49 for deaths resulting in fetal expulsion, and 1.39 and 0.80 for deaths resulting in mummification. The greatest risk of fetal death (119 deaths/10,000 fetuses/d) was observed between 98 and 105 days of gestation, and median age at fetal death ranged from 99.0 to 105.5 days. Abortion density for fetal deaths resulting in mummification for cows conceiving during September (1.61/10,000 fetuses/d) and October (1.63/10,000 fetuses/d) was tenfold greater than that for cows conceiving in February (0.16/10,000 fetuses/d) and was twice that of the overall rate (0.84/10,000 fetuses/d). For cohorts of nonculled cows, abortion rate increased after 5 years of age, after 5 pregnancies, or after 4 calvings. For cows with at least one previous abortion, the proportion aborting (14.50%) was higher than that for cows without a previous abortion (12.14%). For a given gravidity, abortion rate was higher among cows that had experienced a previous abortion, compared with those that had not. These methods and observations may help provide a logical foundation on which to base clinical hypotheses regarding causes of abortion, and they may offer insight into pitfalls of bias and confounding to be anticipated.
Efficacy of tiamulin against experimentally induced Streptococcus suis type-2 infection in swine
Authors: Chengappa M. M. , Pace L. W. , Williams J. A. , Herren C. H. , Ascher S. E.
Published: December 2023

Eighteen 4-week-old pigs were used in a study to evaluate tiamulin in drinking water for control of experimentally induced Streptococcus suis type-2 infection. Pigs in groups A and B (n = 6 pigs/group) were aerosolized with a logarithmic-growth phase culture of S suis type 2, whereas pigs in group C (n = 6 pigs) served as noninfected and nonmedicated controls. After exposure to S suis, pigs in group B were given 180 mg of tiamulin/L of drinking water for 5 days. Pigs in group B consumed more feed (P = 0.009) and gained body weight faster (P = 0.02) than did pigs in group A. Pigs in group A had higher rectal temperature (P = 0.05) for up to 7 days after S suis exposure, higher clinical sign scores (P = 0.008), higher serum cortisol concentration on days 7 and 14, higher gross lesion scores (P = 0.03), and higher microscopic lesion scores (P = 0.01) than did pigs in groups B and C. Gross and microscopic lesions in pigs of groups A and B included meningitis, pneumonia, pleuritis, pericarditis, peritonitis, and synovitis of variable severity. Streptococcus suis type 2 was recovered from tissue specimens of 2 group-A pigs and 1 group-B pig. Data indicated that tiamulin administered via drinking water significantly reduced the effects of S suis type-2 infection.
Sympathetic activation in dogs with congestive heart failure caused by chronic mitral valve disease and dilated cardiomyopathy
Authors: Ware W. A. , Lund D. D. , Subieta A. R. , Schmid P. G.
Published: December 2023

Baseline plasma norepinephrine (ne) and epinephrine (epi) concentrations were measured in dogs with naturally acquired heart failure (hf) caused by either degenerative mitral valve disease and mitral regurgitation (mr) or idiopathic dilated cardiomyopathy (dcm). Compared with controls (clinically normal), dogs with hf had increased plasma ne concentration, which was correlated positively with clinical severity of hf. Dogs with the most severe degree of hf (New York Heart Association functional class IV) had mean ne concentration significantly (P < 0.05) greater than that of dogs with all other functional classes of hf. Overall, mean ne concentration in dogs with dcm was greater than that in dogs with mr. Plasma epi concentration was not different between control dogs and dogs with hf or between dogs with dcm or mr. Correlations were not found between the echocardiographically derived end systolic volume index (used as an estimate of myocardial function) and plasma ne and epi concentrations or serum sodium or potassium concentration. Dogs with dcm, as a group, had a small but Significant (P < 0.05) decrease in serum sodium concentration, compared with dogs with mr. This difference was maintained only for class-IV hf when dogs were separated according to functional hf class. In dogs with dcm, Significant inverse correlation was found between plasma ne and serum sodium concentrations. When grouped together, all dogs with hf maintained this relationship; however, dogs with mr did not have correlation between plasma ne and serum sodium concentrations. Plasma epi and serum sodium concentrations were not correlated for any group. It was concluded that in dogs, plasma ne, but not epi, concentration is high in relation to the clinical severity of naturally acquired hf. Although dogs with dcm overall had greater increase in plasma ne concentration than did dogs with primary mr, a direct relation was not evident between a noninvasive estimate of myocardial function and plasma ne concentration. The lower serum sodium values found in dogs with dcm, especially those with most severe clinical hf, along with the higher mean plasma ne concentration, may indicate a greater degree of decompensation and neurohumoral activation, compared with that in dogs with mr.
Epizootiologic patterns of diabetes mellitus in cats: 333 cases (1980-1986)
Authors: Panciera David L. , Thomas Chester B. , Eicker Steven W. , Atkins Clarke E.
Published: December 2023

Medical records from 333 cats with diabetes mellitus were studied retrospectively, using epidemiologic methods to determine the incidence of and risk factors for diabetes mellitus in this species. Abstracts were derived, using the Veterinary Medical Data Program with its 17 participating academic institutions in the United States and Canada. A reference population of 135,651 cats was derived from the same hospital population and time span (july 1980 to June 1986).

The incidence of diabetes mellitus in cats was determined to be 2.45 cases/1,000 cat-years-of-risk during the 6-year study period. Breed had no detectable effect on risk for diabetes mellitus. In contrast, body weight, age, gender, and neutering had a significant (P ≤ 0.01) effect. Body weight of cats was categorized as being < or ≥ 6.8 kg. The higher body weight, probably indicating obesity, contributed a 2.2-fold increase in risk, even after adjustment for age and gender (adjusted odds ratio). The etiologic fraction for high body weight was 3.8%, suggesting that an estimated 3.8% of cases of diabetes mellitus was attributable to this factor alone. Over 50% of diabetic cats were > 10 years old, and the etiologic fraction for age > 7 years alone was 73.5%. Age was a significant (P < 0.001) and the most important single risk factor for development of the disease in cats, with adjusted odds ratios of 8.3 and 14.4 for age 7 to 10 years and > 10 years, respectively. Unlike human beings and dogs, male cats were at 1.5 times greater risk for developing diabetes mellitus than were females, and neutered cats were at nearly twice the risk as sexually intact cats. The adjusted odds-risk ratio for neutered males, sexually intact males, spayed females, and sexually intact females was 2.8, 2.1, 1.9, and 1, respectively.
Rabies surveillance in the United States during 1989
Authors: Reid-Sanden Frances L. , Dobbins James G. , Smith Jean S. , Fishbein Daniel B.
Published: December 2023

In 1989, 4,808 cases of rabies in animals other than human beings were reported to the Centers for Disease Control, 1.8% more (4,724 to 4,808) than in 1988. Eighty-eight percent (4,224/4,808) of those affected were wild animals and 12% (584/4,808) were domestic animals. Cases were reported from 49 states, the District of Columbia, and Puerto Rico; Hawaii remained rabies-free. Skunks (1,657) continued to be the most commonly reported rabid wild animal. For the second consecutive year, more cats (212) were reported to be infected with rabies virus than any other domestic species. Compared with their 1988 reports, 5 states reported increases of greater than 100% (Alaska, 109%; New Jersey, 233%; Ohio, 133%; Oklahoma, 168%; and Washington, 125%), and 5 states reported decreases of greater than 50% (Connecticut, 63%; Mississippi, 56%; Montana, 67%; Nevada, 55%; and West Virginia, 53%) in 1989.
Prolongation of anesthesia with xylazine, ketamine, and guaifenesin in horses: 64 cases (1986-1989)
Authors: McCarty John E. , Trim Cynthia M. , Ferguson Duncan
Published: December 2023

On 74 occasions, 54 horses and 6 foals were anesthetized with xylazine and ketamine or xylazine, guaifenesin, and ketamine, with or without butorphanol. On 64 occasions, anesthesia was prolonged for up to 70 minutes (34 ± 15 min) by administration of 1 to 9 supplemental iv injections of xylazine and ketamine at approximately a third the initial dosage. All horses except 5 were positioned in lateral recumbency, and oxygen was insufflated.

In adult horses, the time from induction of anesthesia to the first supplemental xylazine and ketamine injection was 13 ± 4 minutes and the time between supplemental injections was 12.1 ± 3.7 minutes. These results were consistent with predicted plasma ketamine concentration calculated from previously published pharmacokinetic data for ketamine in horses. Respiratory and heart rates and coccygeal artery pressure remained consistent for the duration of anesthesia. The average interval between the last injection of ketamine and assumption of sternal position was approximately 30 minutes, and was the same regardless of the number of supplemental injections. The time to standing was significantly longer (P < 0.05) in horses given 2 supplemental injections, compared with those not given any or only given 1, but was not longer in horses given 3 supplemental injections. Recovery was considered unsatisfactory in 5 horses, but did not appear to be related to prolongation of anesthesia.
Histopathologic study of uveitis in cats: 139 cases (1978-1988)
Authors: Peiffer Robert L. , Wilcock Brian P.
Published: December 2023

Histopathologic findings in 158 globes obtained from 139 cats by enucleation or at necropsy, with histopathologic diagnosis of uveitis, were compared, and morphology was correlated with clinical and/or histopathologic diagnosis. The most common morphologic feature was a lymphocytic-plasmacytic anterior uveal infiltrate that was either diffuse or nodular; specific cause could not be associated with this nongranulomatous anterior uveitis. In decreasing order of frequency, other common causes of uveitis in cats included feline infectious peritonitis; FeLV-associated lymphosarcoma; trauma; and lens-induced uveitis.
Relationship of strain 19 calfhood vaccination in beef herds and brucellosis reactor rates, duration of quarantine, and number of herd tests
Authors: Dietrich R. A. , Amosson S. H. , Crawford R. P. , Beal V. C.
Published: December 2023

Initial and cumulative reactor rates for strain 19 vaccinates and nonvaccinates were significantly (P < 0.001) lower for beef herds containing variable proportions of vaccinates, compared with reactor rates in nonvaccinated herds. In addition, significant (P < 0.005) reduction in cumulative incidence was observed in nonvaccinated and strain 19-vaccinated cattle as the proportion of vaccinates within the herd increased from 1 to 19%, 20 to 39%, 40 to 59%, and 60 to 100%. Duration of quarantine and number of herd tests were not reduced in herds with strain 19-vaccinated cattle. In herds released from quarantine, duration of quarantine and number of tests were positively correlated to proportion of the herd vaccinated. In nonvaccinated herds released from quarantine, effect of herd size was documented by strong positive (P = 0.042) correlation with duration of quarantine and slightly weaker correlation (P = 0.095) with number of tests.
Prognostic factors and survival of horses with ocular/adnexal squamous cell carcinoma: 147 cases (1978-1988)
Authors: Dugan Steven J. , Roberts Steven M. , Curtis Charles R. , Severin Glenn A.
Published: December 2023

Between January 1978 and December 1988, 147 horses with ocular/adnexal squamous cell carcinoma (scc) were admitted to the Colorado State University Veterinary Teaching Hospital (CSU-VTH). Diagnosis was conjirmed by histologic examination of appropriate tissue specimens. Medical records and communication with owners, referring veterinarians, or both provided information regarding initial examination, treatment at the CSU-VTH, and final outcome. At initial examination, 123 (83.7%) horses had unilateral involvement and 24 (16.3%) horses had bilateral involvement. The nictitating membrane, nasal canthus, or both (28.1%); limbus (27.5%); and eyelid (22.8%) were most commonly affected. In addition to the ocular/adnexal location, scc was found elsewhere in 14 (9.5%) horses at initial examination. Adequate follow-up (≥ 4 months) for examination of tumor recurrence and survival analysis was obtained for 125 (85.0%) cases. After treatment at the CSU-VTH, tumor recurred in 30.4% of the cases. Tumor location, multiple vs single tumors at initial diagnosis, and CSU-VTH treatment modality influenced the recurrence of tumors. Survival analysis revealed a good prognosis for horses with ocular/adnexal scc. Although undefined, a conservative estimate of the median survival time was 47 months. Six factors (treatment prior to referral, tumor location, tumor size, single or multiple tumors, treatment modality at the CSU-VTH, and recurrence or nonrecurrence) were analyzed to determine their relation with survival. Treatment prior to referral, multiple vs single tumors at initial examination, and treatment modality used at the CSU-VTH did not influence survival. Tumor location influenced survival; scc involving the eyelid or orbit was associated with the poorest prognosis. Tumor stage (maximal dimension) was inversely related with survival. One or more recurrences of scc markedly reduced the likelihood of survival.
Transfusion of type-A and type-B blood to cats
Authors: Giger Urs , Bücheler Jorg
Published: December 2023

Although nearly all domestic shorthair and longhair cats have type-A blood (> 99%), the frequency of blood type B in various feline breeds ranges from 0 to 59%. All blood-type-B cats have strong natural alloantibodies, predominantly of the IgM class, whereas blood-type-A cats have low alloantibody titers of the IgG and IgM classes. We therefore studied the efficacy and safety of transfusing 20 ml of matched and mismatched 14C-potassium cyanate-labeled blood to cats. In autologous and allogeneic matched transfusions of blood-type-A and type-B cats, the half-life of labeled erythrocytes proved to be similar (29 to 39 days). In contrast, type-B erythrocytes transfused into 5 blood-type-A cats had a mean (± sd) half-life of only 2.1 ± 0.2 days and induced minor transfusion reactions. Half of the type-A blood given to 4 blood-type-B cats was destroyed within minutes to 6 hours (mean ± sd = 1.3 ± 2.3 hours), depending on the alloantibody titer. After 1 day, none of the labeled erythrocytes were detected. Mismatched transfusions in blood-type-B cats caused marked transient reactions including systemic anaphylactic signs (hypotension, bradycardia, apnea, urination, defecation, vomiting, and severe neurologic depression) and hemolytic signs (hemoglobinemia and pigmenturia) associated with severe reduction in plasma alloantibody titer and complement activity.

We conclude that the rapid destruction of type-A erythrocytes transfused into blood-type-B cats predominantly occurs intravascularly and is complement- and IgM-mediated, whereas type-B erythrocytes administered to blood-type-A cats are mostly extravascularly hemolysed by a process involving small amounts of IgG and IgM, but without marked complement activation. Thus, any first or subsequent AB-mismatched transfusions are ineffective and life threatening. We therefore recommend the practice of blood typing or cross-matching prior to transfusing blood in cats to prevent any incompatibility reactions and to assure efficacy.