bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of a scheme for predicting the gram-staining reaction of organisms causing bovine mastitis
Authors: Jones Gary F. , Ward G. E.
Published: December 2023

The accuracy of a scheme for predicting the gram-staining reaction of organisms causing bovine mastitis in cows with systemic signs of disease (anorexia) was evaluated over 1 year. Criteria for making the predictions included: season of year, stage of lactation, appearance of milk, detection and duration of teat injuries, and milk odor. It was possible to determine the cause by microbiologic culture of specimens from 136 of the 147 cows of the study. Of 78 infections caused by gram-negative (mostly coliform) organisms, 62 (79%) were predicted accurately to be caused by gram-negative organisms. Of 57 infections caused by gram-positive organisms, 45 (79%) were predicted correctly to be caused by gram-positive organisms. Correctly predicted as gram-positive organisms causing infection were: Actinomyces pyogenes in 20 of 21 (95%) cows; Staphylococcus sp in 14 of 22 (64%) cows; Streptococcus sp in 10 of 13 (77%) cows and Bacillus sp in 1 cow. Overall accuracy, in those instances when bacteria were isolated (136 cows), was 78%.
A survey of equine parasite control practices in Tennessee
Authors: Reinemeyer Craig R. , Rohrbach Barton W.
Published: December 2023

A weighted, random sample of 130 horse owners in Tennessee was selected from subscribers to an equine newsletter published by the Agricultural Extension Service. Data about the participants' farms, horses, parasite control practices, and sources of information regarding equine parasite control were obtained through a telephone survey. The response rate was 98%.

The typical respondent kept 4 horses on 2 pastures totaling 15 acres, and did not rotate pastures as a parasite control measure. The majority (83%) of horse owners indicated that they administered anthelmintics according to a regular schedule; 9% delayed deworming until the onset of weight loss.

Proportions of owners deworming the various classes of horses at least 1, 2, 3, or 4 times annually were as follows: foals (0 to 6 months) 100, 60,15, and 0%, respectively; weanlings (6 to 12 months) 100, 91, 32, and 0%, respectively; yearlings (1 to 2 years) 100, 100,86, and 51%, respectively; and adults (> 2 years) 100, 94, 56, and 24%, respectively. Median treatments of yearlings and adults were evenly spaced at 6-, 4-, or 3-month intervals when the owners dewormed 2, 3, or 4 times annually, respectively. Mean intervals between treatments of foals and weanlings were less regular.

Of the horse owners who dewormed 2 or more times annually, most (53 to 80%) used the same product exclusively for all treatments. In all age classes of horses, ivermectin paste (46 to 63%) was the most common product used, followed by tube deworming (23 to 38%) and use of benzimidazoles (4 to 16%). Nearly all respondents (98%) planned to use the same anthelmintics the next year, and 91% intended to maintain the same frequency of treatment.

Equine-oriented magazines (41%) and veterinarians (27%) were considered the most important sources of information about when to deworm horses, and veterinarians (75%) were the most important source of information about which product to use.
Differentiation between intra-abdominal neoplasms and abscesses in horses, using clinical and laboratory data: 40 cases (1973-1988)
Authors: Zicker Steven C. , Wilson W. David , Medearis Ilsi
Published: December 2023

The medical records of 25 horses with intra-abdominal neoplasms and 15 horses with intra-abdominal abscesses were reviewed. Common clinical signs of disease observed by owners of horses in both groups included anorexia, weight loss, fever, signs of colic, and depression. Clinical laboratory abnormalities included leukocytosis, hyperfibrinogenemia, hypoalbuminemia, and hypocalcemia. There was considerable overlap of laboratory test results within and between the 2 groups of horses. Peritoneal fluid was classified as an exudate in 12 of 15 horses with intra-abdominal abscesses and in 14 of 25 horses with intra-abdominal neoplasms. Cytologic examination of peritoneal fluid yielded an accurate diagnosis in 11 of 25 horses with neoplasia and in 3 of 15 horses with abscesses. A mean number of 1.45 cytologic analyses/horse was needed to diagnose neoplasms in the 11 horses in which the analysis was successful in definitively diagnosing the condition.
Decreased erythrocyte potassium concentration associated with exercise-related myopathy in horses
Authors: Bain Fairfield T. , Merritt A. M.
Published: December 2023

To investigate the possibility that a disorder of potassium balance may have a role in the development of equine rhabdomyolysis, the potassium concentration within erythrocytes (RBC [K+]) and plasma (P [K+]) was measured in 3 groups of horses: group 1, eight 2-year-old fillies that had postexercise muscle soreness within 48 hours of sample collection; group 2, ten 2-year-old fillies subjected to identical management and training conditions (as fillies of group 1) and that did not have signs of myopathy; and group 3, 32 yearlings of both sexes on the farm of origin of groups 1 and 2 that were pastured and not in training. Creatine kinase activity in serum from horses of groups 1 and 2 was also measured. The mean P [K+] was not significantly different between groups, whereas the mean RBC [K+] was significantly (P < 0.01) lower in group-1 fillies vs group-2 fillies and group -3 horses. Group-1 fillies also had markedly high serum creatine kinase activity. Results of the study revealed significantly lower RBC [K+] in horses that had had signs of myopathy within the preceding 48 hours. This does not prove a causal relationship between RBC potassium depletion and myopathy, but does suggest that decreased RBC [K+] may be observed in horses with exercise-related myopathy.
Prevalence of trichomoniasis among California beef herds
Authors: BonDurant R. H. , Anderson M. L. , Blanchard P. , Hird D. , Danaye-Elmi C. , Palmer C. , Sischo W. M. , Suther D. , Utterback W. , Weigler B. J.
Published: December 2023

Sixty cow-half herds of more than 50 cows each were randomly selected for a prevalence survey of bovine trichomoniasis in California. Herd size, as judged by the number of bulls, ranged from 1 to 210 bulls (median = 8; mean = 59 ± 15.8). Preputial smegma was collected from 729 bulls (median = 6 bulls/herd) and cultured for Tritrichomonas foetus. Of 57 herds from which samples were collected, 9 (15.8%) had at least one infected bull. Of the 729 bulls from which samples were cultured, 30 (4.1%) were infected. Correcting for sensitivity of the diagnostic test yielded a prevalence of 5.0%. Infection rates for bulls >3 years old and ≤3 years old were 6.7% and 2.0%, respectively (P > 0.025). Median herd sizes were 14 bulls (range, 6 to 114) for infected herds and 7 (range, 1 to 210) for uninfected herds. These findings suggest that trichomoniasis is common in California beef herds. Because several bulls <4 years old were infected, we suggest that control measures stressing replacement of older bulls with younger ones should be combined with diagnostic procedures in those younger replacements, to ensure that they are not already infected.
Ultrasonographic findings in horses with cholelithiasis: Eight cases (1985-1987)
Authors: Reef Virginia B. , Johnston Janet K. , Divers Thomas J. , Acland Helen
Published: December 2023

Cholelithiasis and/or obstructive biliary tract disease was diagnosed ultrasonographically in 8 horses, 5 to 15 years old. Ultrasonographic findings revealed greater than normal amount of hepatic parenchyma in the right side of the abdomen in 8 horses and in the left side in 3 horses. The echogenicity of the liver was greater than normal, and thick distended bile ducts were seen in all horses. Choleliths were imaged ultrasonographically in 6 horses.

Subsequently, postmortem findings in 6 horses revealed periportal and intralobular fibrosis, moderate bile duct dilatation, proliferation, and cholestasis. One or more choleliths were found in all horses. Ultrasonographic findings accurately depicted the histologic changes in the hepatic parenchyma in horses with cholelithiasis.
Lack of supportive susceptibility data for use of ampicillin together with trimethoprim-sulfonamide as broad-spectrum antimicrobial treatment of bacterial disease in dogs
Authors: Hirsh Dwight C. , Jang Spencer S. , Biberstein Ernst L.
Published: December 2023

The combination of ampicillin together with trimethoprim-sulfonamide is sometimes used as a broad-spectrum antimicrobial regimen for treatment of dogs with bacterial infections of unknown etiopathogenesis. To determine whether this combination is indeed broad spectrum, we analyzed susceptibility data derived from commonly encountered bacterial agents in dogs.

A total of 381 isolates from 344 cases was studied. Overall, 80 (20.9%) of the 381 isolates were resistant to ampicillin and to trimethoprim-sulfonamide; 159 (41.7%) were resistant to ampicillin, but susceptible to trimethoprim-sulfonamide; 131 (34.4%) were susceptible to both ampicillin and trimethoprim-sulfonamide; and 11 (2.9%) were susceptible to ampicillin, but resistant to trimethoprim-sulfonamide. Of isolates susceptible to ampicillin and/or trimethoprim-sulfonamide, 290 (96.3%) were susceptible to trimethoprim-sulfonamide (ampicillin increased the coverage by 3.7%). On the other hand, 142 (47.2%) were susceptible to ampicillin. In addition, with respect to agents most commonly encountered (members of the family Enterobacteriaceae and members of the genus Staphylococcus), combining ampicillin with trimethoprim-sulfonamide increased coverage by 2.2% over use of trimethoprim-sulfonamide alone.

We contend, therefore, that use of ampicillin together with trimethoprim-sulfonamide does not result in an acceptable broad-spectrum antimicrobial regimen for treatment of bacterial disease in dogs.
Evaluation of heartworm immunodiagnostic tests
Authors: Courtney Charles H. , Cornell John A.
Published: December 2023

In this report, the use of appropriate statistical methods for the evaluation of heartworm immunodiagnostic tests is discussed. The evaluation of these tests is complicated by factors causing variation in sensitivity, specificity, accuracy, and predictive values of positive and negative test results. The primary sources of inconsistency are variation in the prevalence of heartworm infection among populations of dogs and the sensitivity of immunodiagnostic tests to various categories of heartworm infections (ie, patent, immune-mediated occult, unisex occult, and immature occult). Sample size (ie, number of dogs tested) affects the confidence limit values of sensitivity and specificity. At least 100 dogs should be used in each testing group (infected and uninfected) to generate values of sensitivity or specificity within reasonably narrow confidence limits. Use of more than 200 dogs in each testing group contributes little to further narrowing of confidence limits. The selection of appropriate statistical tests for comparison of tests or comparison of the sensitivity or specificity of a single diagnostic test to various categories of heartworm infections is critical. The McNemar paired χ2 test is appropriate for comparison of diagnostic tests, but it must be done by use of duplicate sera from each animal. A χ2 test of independence, or, in the case of a small sample size, the Fisher exact test, is appropriate for comparing the sensitivity or specificity of a single diagnostic test to various categories of heartworm infection.
Hyperkalemic periodic paralysis in horses
Authors: Spier Sharon J. , Carlson Gary P. , Holliday Terrell A. , Cardinet George H. , Pickar Joel G.
Published: December 2023

Eleven horses (3 mares, 7 stallions, 1 gelding) with clinical and biochemical evidence of hyperkalemic periodic paralysis were studied. Each horse had history of episodic weakness, muscular tremors, or collapse, which lasted for periods of a few minutes to hours. Diagnosis was based on hyperkalemia in association with a spontaneous episode of paralysis or by precipitation of an episode by oral administration of potassium chloride. Clinical and biochemical events were documented during spontaneous and induced episodes of muscular weakness. During episodes, electrocardiographic findings were consistent with hyperkalemia. Electromyography performed between episodes revealed fibrillation potentials and positive sharp waves, complex repetitive discharges, and myotonic discharges. Histologic changes in muscle biopsy specimens varied from no overt changes in some horses to vacuolation in type-2B fibers with mild degenerative changes in other horses. Electron microscopy of myofibers revealed dilatations of the sarcoplasmic reticulum.

Analysis of blood samples taken serially during induced attacks in 5 horses revealed marked hyperkalemia (5.5 to 9.0 mEq/L), with normal acid-base status, hemoconcentration, and modest changes in muscle-derived enzymes. Close correlation (r2 = 0.882) between total plasma protein and plasma potassium concentrations was observed and indicated a shift of fluid out of the extracellular fluid compartment. Treatment of either spontaneous or induced episodes by iv administration of calcium, glucose, or bicarbonate resulted in rapid recovery. Dietary management or daily administration of acetazolamide effectively controlled episodes.

An affected mare was bred to an affected stallion, and 3 affected offspring were produced by embryo transfer. Blood samples from another extended family of affected horses were analyzed for identification of a genetic marker. Blood typing, including 22 loci, revealed no linkage with erythrocytic or serum markers. Lymphocyte typing for equine lymphocytic antigen markers also failed to reveal any linkage.
Erythrocyte dyscrasia, anemia, and hypothyroidism in chronically underweight llamas
Authors: Smith Bradford B. , Reed Pamela J. , Pearson Erwin G. , Long Patrick , Lassen E. Duane , Watrous Barbara J. , Lovelady Sandy , Sims David E. , Snyder Stan P.
Published: December 2023

A syndrome characterized by anemia, erythrocyte dyscrasia, low body weight, and hypothyroidism was observed in 8 llamas (Lama glama). At initial examination (1 to 23 months of age; median, 7.5 months), llamas (3 males, 5 females) were markedly underweight (29 to 55 kg; median, 36 kg) and anemic (pcv, 12.9 to 25.5% [median, 19%]). Five of the llamas became progressively more anemic over time; in 2 of them, pcv decreased to < 10%. Erythrocyte changes included severe poikilocytosis, anisocytosis, asymmetric distribution of hemoglobin within the cytoplasm, and cytoplasmic extensions from one or both poles. Six llamas had moderate to severe valgus deformities of the carpus. All llamas had low baseline serum thyroxine concentration and diminished response to thyrotropin administration. Baseline and post-thyrotropin triiodothyronine concentrations did not have consistent patterns. Five llamas were hypophosphatemic and 7 had low serum iron concentration (iron concentration was not determined in 1 llama). Orally administered iron supplementation did not induce clinical improvement. Because 3 of the affected llamas were full sisters, a genetic basis for the problem has to be considered. It was not possible to evaluate the familial relationship of the other 5 affected llamas. Although the underlying cause of the problem was not established, the prognosis for affected llamas is guarded to poor.
Evaluation of relationship between plasma fibrinogen concentration and tuberculin testing in red deer
Authors: Cross J. P. , Reynolds G. E. , Mackintosh C. G. , Griffin J. F. T.
Published: December 2023

After intradermal injection of bovine purified derivative (ppd), increases in plasma fibrinogen concentration and plasma viscosity developed in red deer (Cervus elaphus) with a history of tuberculosis caused by Mycobacterium bovis. Serum haptoglobin concentrations were also found to increase under similar circumstances. The increases were reproducible and did not appear to be related to mustering, stress, or the handling associated with injection of ppd. A significant (P < 0.05) direct relationship was found between the increase in plasma fibrinogen concentration and various markers of bovine tuberculosis infection, such as stimulation of lymphocyte transformation in response to bovine ppd and the diameter of intradermal tuberculin skin test reactions. A stronger correlation (P < 0.01) was found with the volume of intradermal tuberculin skin test reactivity, and the strongest correlation (P < 0.001) was with the presence of circulating antibovine ppd antibody.
Spread of pseudorabies virus among breeding swine in quarantined herds
Authors: Duffy Sergio J. , Morrison Robert B. , Thawley David G.
Published: December 2023

In theory, pseudorabies virus (prv) may be eliminated from any size of breeding herd by phased test and removal if replacement gilts are not infected with prv, culling decisions are partially based on prv status, and the cull rate is higher than the incidence rate of prv. Annual cull rates are commonly at least 50%, but little information exists on the incidence of prv within enzootically infected swine herds. The purpose of this study was to develop a method by which spread of prv could be detected among breeding swine within enzootically infected herds and to determine the incidence of prv infection in these herds. Data were collected from 17 herds that were quarantined for prv and ranged in size from 120 to 1,100 sows. At each herd, within the first 5 days of introduction, a group of approximately 30 replacement gilts was identified, vaccinated with a glycoprotein X-deleted prv vaccine, and blood sample was collected. The owner of 1 herd had a nonvaccinated breeding herd and elected to leave incoming gilts nonvaccinated. After vaccination, blood samples were collected every 1 to 2 months for an average of 13.6 months. Serum samples from vaccinated gilts were tested for antiglycoprotein X antibodies by a specific differential elisa. Samples from nonvaccinated gilts were evaluated by serum neutralization test. Product-limit method was used to estimate the probability of not becoming infected with prv. Spread was detected in 7 of 8 herds that had more than 400 sows and in 2 of 9 herds that had less than 400 sows. The minimal elapsed time between introduction and detection prv infection varied from 2 to 6 months. In the 9 herds in which spread was detected, the probability that a replacement gilt did not become infected ranged from 53% at month 10 after introduction to 95% at month 15. Annual incidence ranged from 61% to 4.7%, respectively. When prv was detected, it spread slowly and sporadically. Therefore, assuming that replacement gilts remain negative and that the culling decision could be made partially on prv status, phased testing and removal would be a viable method to eliminate prv from most of these herds.
Prevalence of nephrotoxicosis associated with a short-term saline solution diuresis protocol for the administration of cisplatin to dogs with malignant tumors: 61 cases (1987-1989)
Authors: Ogilvie Gregory K. , Straw Rodney C. , Powers Barbara E. , Cooper Mary F. , Withrow Stephen J.
Published: December 2023

The study reported here was undertaken to determine the nephrotoxicosis associated with the administration of cisplatin, an antineoplastic agent, to dogs when administered during 6-hour saline solution diuresis. Cisplatin (70 mg/m2 of body surface, iv, every 21 days) was given to 61 dogs with malignant neoplasia with a total of 185 doses in 1 (n = 9 dogs), 2 (n = 26 dogs), 3 (n = 4 dogs), 4 (n = 9 dogs), 5 (n = 2 dogs), and 6 (n = 11 dogs) treatments. The cisplatin was given over a 20-minute period after 0.9% NaCl solution (saline solution) was administered iv for 4 hours at a rate of 18.3 ml/kg of body weight/h. After the cisplatin infusion, saline solution diuresis was continued at the same rate for 2 hours. Before each treatment with cisplatin, dogs were evaluated with at least a physical examination, cbc, determination of serum urea nitrogen concentration, and in most cases, determination of serum creatinine concentration and urine specific gravity. Four of the 61 dogs (6.6%) developed clinically evident renal disease after 2 (1 dog), 3 (2 dogs), and 4 (1 dog) doses of cisplatin were administered. Three of the 4 dogs had preexisting disease of the urinary tract prior to the start of treatment. The survival time in dogs that developed renal disease (median, 145 days; range, 15 to 150 days) was similar to that of all dogs in this study (median, 154 days; range, 30 to 500 days), with 13 dogs still alive at the conclusion of the study. Three of the 4 dogs that developed renal disease were euthanatized because of tumor-related causes and chronic renal failure, whereas the fourth died as a direct result of nephrotoxicosis. Therefore, the 6-hour saline solution diuresis protocol used in this study to administer cisplatin appears to be effective in preventing nephrotoxicosis in dogs with tumors without preexisting urinary tract disease.
Epizootic of pseudorabies among ten swine herds
Authors: Scheidt A. B. , Rueff L. R. , Grant R. H. , Teclaw R. F. , Hill M. A. , Meyer K. B. , Clark L. K.
Published: December 2023

An epizootic of pseudorabies in 10 swine herds located near Greensburg in Decatur County, Indiana was investigated. Records of Decatur County swine herds previously quarantined because of pseudorabies were obtained. For the 1988 epizootic, clinical findings were considered, location of each of the 10 swine herds in relation to the other herds was determined, and potential fomites were considered. Meteorologic data prior to, during, and after the epizootic were obtained, correlated, and analyzed. A source-receptor model, based on wind direction and speed data, was used to determine whether weather conditions in the Greensburg area enhanced the potential for aerosol spread of pseudorabies virus between herds. On the basis of lack of other modes of spread of pseudorabies and on meteorologic and source-receptor data, aerosol transmission of pseudorabies virus between the 10 herds was probable.
Comparison of procedures for assessing adequacy of dog foods
Authors: Huber Thomas L. , Laflamme Dorothy P. , Medleau Linda , Comer Karen M. , Rakich Pauline M.
Published: December 2023

Dog foods with similar claims for nutritional adequacy were tested by chemical analysis and the American Association of Feed Control Officials’ growth trial. All foods tested were similar chemically, however, dogs given one regionally marketed food had lower growth rate and food efficiency as well as suboptimal pcv and hemoglobin values during the growth trial. Pups fed this diet also had clinical signs typical of zinc and copper deficiencies. We concluded that American Association of Feed Control Officials’ approved feeding tests provide valid assessment of pet food quality, and procedures involving only chemical analysis or calculated values may not.
In situ observation of the ovaries of llamas and alpacas by use of a laparoscopic technique
Authors: Sumar Julio , Bravo P. Walter
Published: December 2023

A laparoscopic technique was used to observe in situ the ovaries of llamas and alpacas. Use of this technique results in minimal surgical stress and allows repetitive observation of various reproductive stages in the same animal. Ovarian follicular activity before and after breeding, time of ovulation, corpus luteum formation and regression, early embryo death, failure of ovulation, and the early events of pregnancy can be assessed quickly and safely. For 1,291 laparoscopies performed, postsurgical disturbance was not observed, and animals were released from the clinic 1 hour after laparoscopy.
Feline leukemia virus infection and diseases
Authors: Hoover Edward A. , Mullins James I.
Published: December 2023

Feline leukemia virus is a naturally occurring, contagiously transmitted and oncogenic immunosuppressive retrovirus of cats. The effects of FeLV are paradoxical, causing cytoproliferative and cytosuppressive disease (eg, lymphoma and myeloproliferative disorders vs immunodeficiency and myelosuppressive disorders). In the first few weeks after virus exposure, interactions between FeLV and hemolymphatic system cells determine whether the virus or the cat will dominate in the host/virus relationship—persistent viremia and progressive infection or self limiting, regressive infection will develop. The outcome of these early host/virus interactions is revealed in the diagnostic assays for FeLV antigenemia and viremia. The latter, in turn, predict the outcome of FeLV infection in cats. Known host resistance factors include age and immune system functional status. Known virus virulence factors are magnitude of exposure and virus genotype. Molecular analysis of FeLV strains indicated that natural virus isolates exist as mixtures of closely related virus genotypes and that minor genetic variations among FeLV strains can impart major differences in pathogenicity. The genetic coding regions responsible for cell targeting and specific disease inducing capacity (eg, thymic lymphoma, acute immunosuppression, or aplastic anemia) have been mapped to the virus surface glycoprotein and/or long terminal repeat regions for several FeLV strains. Infection by specific FeLV strains leads to either malignant transformation or cytopathic deletion of specific lymphocyte and hemopoietic cell population, changes that prefigure the onset of clinical illness. Another notable feature of the biology of FeLV is that many cats are able to effectively contain and terminate viral replication, an important example of host immunologic control of a retrovirus infection and a process that can be selectively enhanced by vaccination. Thus, FeLV infection serves as a natural model of the multifaceted pathogenesis of retroviruses and as a paradigm for immunoprophylaxis against an immunosuppressive leukemogenic retrovirus.
Protection against feline leukemia virus infection by use of an inactivated virus vaccine
Authors: Hoover Edward A. , Perigo Nancy A. , Quackenbush Sandra L. , Mathiason-DuBard Candace K. , Overbaugh Julie M. , Kloetzer William S. , Elder John H. , Mullins James I.
Published: December 2023

The protective immunity induced by 3 experimental FeLV vaccines were evaluated: Prototype inactivated FeLV vaccine developed from a molecularly cloned FeLV isolate (FeLV-faids-61E-A); a mixture of immunodominant synthetic peptides corresponding to regions of the FeLV-Gardner-Arnstein-B (FeLV-GA-B) envelope proteins; and an adjuvant-disrupted but non-activated virus prepared from a non-cloned FeLV field isolate comprised of subgroup A and B viruses (FeLV-05821-AB). Included as controls were parallel groups of cats inoculated with adjuvants alone or with an established commercial FeLV vaccine. After each inoculation and after virulent virus challenge exposure, sera from all cats were assayed for elisa-reactive antibody against purified FeLV, FeLV neutralizing (vn) antibody, and FeLV antigenemia/viremia—viral p27 antigen in serum and within circulating leukocytes. Immunity was challenged by oral/nasal exposure of vaccinated and control cats with FeLV-faids-61E-A or FeLV-05821-AB, an infective. noncloned, tissue-origin, FeLV field isolate containing suhgroup-A and -B viruses. Vaccine-induced immunity was assessed by comparing the postchallenge-exposure incidence of persistent viremia and the pre- and postchallenge exposure titers of vn and elisa antibody in cats of the control and vaccine groups. The percentage of cats that resisted development of persistent viremia after FeLV challenge exposure and the preventable fraclion (pf) for the vaccine groups (which adjusts for the severity of the challenge and the degree of innate resistance in the controls) were as allows: adjuvant controls, 26%; FeLV-faids-61E-A inactivated virus vaccine, 95% (pf = 93.2%); FeLV-GA-B peptide vaccine, 5% (−28.4%); FeLV- 05821-AB noninactivated vaccine, 67% (55.4%); and commercial FeLV vaccine, 35% (12.2%). The prechallenge exposure mean vn antibody titer for each group was: <1:8 in the adjuvant controls; 1:43 in the FeLV-faids-61E-A-vaccinated cats; <1:8 in the peptide-vaccinated cats; 1:38 in the noninactivated virus-vaccinated cats group; and 1:12 in the cats vaccinated with the commercial vaccine. Thus, induction of vn antibody in the vaccinated cats, although modest, appeared to be correlated with induction of protective immunity as defined by resistance to FeLV challenge exposure. Results of these studies indicate that inoculation of cats with an experimental inactivated virus vaccine prepared from a molecularly cloned FeLV isolate was most effective in stimulating protective immunity against heterologous and homologous FeLV challenge exposure.
Brachygnathia in horses: 20 cases (1979-1989)
Authors: Gift Lisa J. , DeBowes Richard M. , Clem Michael F. , Rashmir-Raven Ann , Nyrop Karen A.
Published: December 2023

The medical records of 20 horses admitted to the veterinary medical center with a diagnosis of brachygnathia over a 10-year period (1979 to 1989) were reviewed. The study included 18 foals and 2 adult horses. Males were affected 5.7 times more frequently than females. The amount of disparity between the mandible and premaxilla varied between 0.75 and 3 cm. Sixteen foals were treated surgically with the temporary application of premaxillary tension band devices. Thirteen of the 16 surgical cases were available for follow-up evaluation. All of the surgically treated animals had improved incisive occlusion, and 6 foals had complete resolution of the deformity with corrections ranging from 0.75 to 2.5 cm. Complete correction of the malocclusion was more likely to occur if foals were treated when they were ≤ 6 months old. The average amount of correction achieved in foals treated when they were ≤ 6 months old was 1.5 cm. (range, 0.75 to 2.5 cm). Foals treated, when they were 7 to 12 months old, had an average of 0.6 cm of reduction in the malocclusion (range, 0.25 to 1 cm). Implant failure was the most common complication and occurred in 9 of the 13 foals treated surgically.
Serologic and bacteriologic test results after adult vaccination with strain 19 in three dairy herds infected with brucellosis
Authors: Breitmeyer Richard E. , Hird David W. , Carpenter Tim E.
Published: December 2023

Milk culture data and serologic test results were evaluated after adult vaccination with Brucella abortus strain 19 in cattle of 3 large California dairy herds infected with brucellosis. Strain-19 organisms were isolated by culture of milk from 1.9% of the vaccinated cows. Isolation of field strain of B abortus varied directly with magnitude of complement-fixation (cf) and rivanol titers. At time of milk culture, 74% of cows from which field strain was isolated had cf titer ≥ 160, compared with 58% of cows from which strain 19 was isolated. Cows with cf titer ≥160 at 2 months or ≥80 to 4 months after adult vaccination were more likely to be correctly classified as reactors (on the basis of subsequent milk culture results and/or persistently high serologic titer) than were cows with lower cf titer at these times. Cows from which B abortus strain 19 was isolated from milk were more likely to maintain persistent serologic titer than were cows from which neither strain of B abortus was isolated.
Morphometric evaluation of growth in llamas (Lama glama) from birth to maturity
Authors: Smith Bradford B. , Timm Karen I. , Reed Pamela J.
Published: December 2023

Normal growth characteristics of llamas (Lama glama) were evaluated from conception until 1 week after parturition in pregnant females (study 1) and from 1 month after birth to maturity (study 2). In study 1, pregnant multiparous llamas (n = 10) were measured at monthly intervals from conception until 1 week after parturition; in study 2, llamas (n = 270) were measured once. Body weight of pregnant llamas (study 1) did not increase significantly until after the eighth month of pregnancy. Llamas of study 2 reached mature height, length, thoracic circumference, and weight at 18, 24, 36, and 36 months of age, respectively. From 1 month of age to maturity, the growth characteristics of males, nonpregnant females, and females during the first 8 months of pregnancy did not differ. Correlations (r2) between height, length, and thoracic circumference related to body weight for all but the pregnant llamas during the last 3 months of pregnancy were 0.822, 0.834, and 0.948, respectively. The equation describing thoracic circumference as a predictor of body weight was:
Epidemiologic features of von Willebrand's disease in Doberman Pinschers, Scottish Terriers, and Shetland Sheepdogs: 260 cases (1984-1988)
Authors: Brooks Marjory , Dodds W. Jean , Raymond Sharon L.
Published: December 2023

During a study period from 1985 through 1988, plasma von Willebrand's factor antigen (vWF:Ag) concentration was measured as a marker for prevalence of the von Willebrand's disease (vWD) trait in Doberman Pinschers (doberman, n = 5,554), Scottish Terriers (scottie, n = 1,363), and Shetland Sheepdogs (sheltie, n = 4,279). Significant increase in prevalence of the trait was seen in scotties and shelties during this period. In 1988, 73% of dobermans, 30% of scotties, and 28% of shelties tested had abnormal vWF:Ag concentration (<50% vWF:Ag).

We found significant differences between breeds with respect to age and vWF:Ag concentration of clinically affected dogs at time of diagnosis. The affected dobermans were older (doberman mean age, 4.6 years; scottie mean age, 1.7 years; sheltie mean age, 1.9 years) and had higher concentration of plasma vWF:Ag (doberman mean vWF:Ag, 15%; scottie mean vWF:Ag, 0%; sheltie mean vWF:Ag, 8%). Bleeding in affected dogs of all 3 breeds was observed predominantly from mucosal surfaces and from cutaneous sites of surgery or trauma. The most common site of mucosal bleeding in scotties and shelties was oral or nasal cavity, and in dobermans was the urogenital tract.

Differences in clinical manifestations of vWD in purebred dogs may reflect heterogeneous defects within the vWF gene, causing a variety of abnormalities in production, structure, and function of vWF protein. Analogous to vWD in human beings, acquired deficiencies of vWF may also contribute to the clinical variability of vWD in dogs.
Treatment of lead poisoning in wild geese
Authors: Murase Toshiyuki , Ikeda Tomio , Goto Ikuo , Yamato Osamu , Jin Kazuo , Maede Yoshimitsu
Published: December 2023

Twenty-seven wild geese (Anser albifrons) suffering from lead poisoning caused by ingestion of lead shot were treated with disodium calcium ethylenediaminetetraacetate. The concentration of lead in blood ranged from 0.4 to 23.0 μg/ml, with a mean concentration of 5.6 μg/ml. In 22 of the birds, 1 to 48 lead pellets (mean, 10.5 pellets/bird) were seen on radiographs of their gizzards. Eleven of 27 birds recovered 3 to 8 weeks after the initiation of treatment. In the birds that recovered, the lead pellets were rapidly eroded as the birds recovered their appetites in response to treatment, and disappeared radiographically between treatment days 17 and 52. The birds that did not survive died within 4 weeks, despite decreased concentrations of lead in blood. Of these 16 birds, 15 had radiographic evidence of impaction of the proventriculus at the first examination and no evidence of resolution of the impaction at the time of death. In contrast, only 2 of the 11 geese that recovered had impaction of the proventriculus at the time of admission. Thus, the condition of the proventriculus seems to be the first consideration to evaluate in the prognosis of lead poisoning in geese.
Clinical and laboratory findings associated with actual or suspected azoospermia in dogs: 18 cases (1979–1990)
Authors: Olson Patricia N. , Schultheiss Patricia , Seim Howard B.
Published: December 2023

Eighteen dogs were evaluated far azoospermia, 8 of which had sired pups. On the basis of history, physical examination, and various laboratory evaluations, the cause and site of azoospermia varied. Two dogs that had never sired pups had likely been azoospermic from puberty (congenital azoospermia). Two dogs were azoospermic as a result of tumors (Sertoli cell tumor and malignant astrocytoma of the pituitary gland). Deposits of IgG were observed in testicular biopsy samples, which suggested an autoimmune cause for azoospermia in 5 dogs. One of the 5 dogs with IgG deposits in testicular tissues also had evidence of immune-mediated thyroiditis. Culturing of microbes in the semen was not helpful in determining potential causes of azoospermia, and results did not correlate with organisms isolated from testicular biopsy samples or with the finding of inflammation in biopsy samples. Because 6 dogs had relatives with histories of reproductive dysfunction, inbreeding also must be considered when evaluating dogs for azoospermia.
Frequency of reisolation of Staphylococcus aureus from multiple sequential milk samples
Authors: Adams D. Scott , Hancock Dale , Fox Lawrence , McDonald John S.
Published: December 2023

Bacterial cultures were performed on multiple sequential composite samples of milk from 1,172 cows in 9 dairy herds. If the initial diagnosis of Staphylococcus aureus infection was based on the first positive culture, an average of 37.8% of subsequent cultures on the same cows were negative for S aureus. However, if the initial diagnosis of S aureus infection was confirmed by 2 or 2 of 3 sequential positive cultures and any conversions from S aureus positive to negative were confirmed by 2 or 2 of 3 sequential negative cultures, then only 17.0% converted to a negative diagnosis. Conversion of cows from S aureus culture-positive to -negative varied between herds; 8.1 to 69% for single cultures and 0.0 to > 40% for confirmed cultures.
Lymphoma involving large granular lymphocytes in cats: 11 cases (1982-1991)
Authors: Wellman Maxey L. , Hammer Alan S. , DiBartola Stephen P. , Carothers Marcia A. , Kociba Gary J. , Rojko Jennifer L.
Published: December 2023

Medical records of 11 cats with lymphoma involving large granular lymphocytes were reviewed. All 9 cats tested were FeLV-negative. Ten cats had a history of anorexia, lethargy, vomiting, or diarrhea, and had lymphoma involving abdominal viscera. The most common site of tumor in these cats was the jejunum. One cat had cutaneous masses caused by dermal and epidermal infiltration with neoplastic large granular lymphocytes. The most common hematologic abnormality was leukocytosis, characterized by neutrophilia with a left shift (7 cats); 2 cats had a left shift without neutrophilia. None of the cats had lymphocytosis, but immature large granular lymphocytes were found in the blood of 4 cats. The most common serum biochemical abnormalities were hypoalbuminemia (10 cats), hypocalcemia (10 cats), hypoproteinemia (9 cats), high aspartate transaminase activity (9 cats), and hyperbilirubinemia (8 cats).

Large granular lymphocytes were characterized by abundant cytoplasm containing distinct azurophilic granules that varied in size and number. The most common cytochemical staining pattern included detection of α-naphthyl butyrate esterase, acid phosphatase, and β-glucuronidase activities. On examination of histologic sections, granules stained weakly eosinophilic with Giemsa and moderately with periodic acid-Schiff reaction. Ultrastructurally, the granules appeared membrane bound and contained an electron-dense matrix in 4 cats.
Efficacy of microcrystalline desoxycorticosterone pivalate for treatment of hypoadrenocorticism in dogs
Authors: Lynn Randy C. , Feldman Edward C. , Nelson Richard W. , _ _
Published: December 2023

The efficacy of microcrystalline desoxycorticosterone pivalate (docp) therapy was evaluated in 60 dogs with hypoadrenocorticism. Fifty-one of the dogs were being treated with either docp or fludrocortisone acetate prior to entering the study. The disease had been recently diagnosed in 9 dogs that were not under maintenance treatment prior to entering the study. Desoxycorticosterone pivalate (2.2 mg/kg of body weight, im) was administered on days 0, 25, and 50. Physical examination was performed, and blood samples were obtained for serum biochemical analysis (Na+, K+, and bun concentrations) on days 0, 14, 25, 39, 50, 64, and 75. On day 75 of the study, a final physical examination was performed and the course of treatment was evaluated.

Sixty-eight percent (41/60) of the dogs had normal physical findings on day 0 vs 87% (52/60) on day 75. Mean (±sd) body weight increased from 24.8 ± 12.7 kg on day 0 to 26.2 ± 13.7 kg on day 75. Mean serum Na+ (137.7 ± 8.5 mEq/L) and K+ (5.6 1.0 mEq/L) concentrations and Na+-to-K+ ratio (25.4 ± 5.0:1) were outside normal reference limits on day 0. By day 75, serum Na+ (144.3 ± 4.8 mEq/L) and K+ (4.9 ± 0.8 mEq/L) concentrations and Na+-to-K+ ratio (30.4 ± 5.1:1) were normal and were significantly (P < 0.01) improved, compared with the corresponding values on day 0.

Of the 60 dogs, 58 (97%) regained the loss in body weight, appetite, and muscular strength while given docp; once achieved, these improvements were maintained. These 58 dogs did not vomit or have diarrhea, common problems in dogs with hypoadrenocorticism. The mineralocorticoid (docp) alone was not adequate to correct all clinical signs associated with endogenous mineralocorticoid and glucocorticoid deficiencies, which are typical of hypoadrenocorticism in dogs. Thus, 22 of the 58 dogs had glucocorticoid-responsive clinical signs of disease (lethargy, n = 10; anorexia, n = 8; weakness and hypoadrenal crisis, n = 2 each). These signs resolved in response to initiation of glucocorticoid therapy (prednisolone, 2.5 mg/d, po) and/or adjustments in docp dose or dosing interval. Ten dogs developed polyuria, polydipsia, or both during the study; these signs improved when the dose of prednisolone (n = 9) or docp (n = 1) was reduced. All owners but 1 chose to continue docp therapy after the trial ended, and all dogs remained free of clinical signs associated with hypoadrenocorticism for at least 1 year after the study ended.
Upward fixation of the patella in cattle: 38 cases (1984-1990)
Authors: Baird A. N. , Angel K. L. , Moll H. D. , Wolfe D. F. , Morris D. L. , Welch R. D. , Hooper R. N. , Wenzel J. G. W.
Published: December 2023

Case records of cattle admitted to 2 university veterinary hospitals during 6 years were evaluated to determine the age, breed, sex, and treatment of cattle with upward fixation of the patella. Affected cattle were compared with those from the respective hospital populations of cattle admitted during the same time.

Of 38 cattle with upward fixation of the patella, 34 were treated surgically. Follow-up evaluation was obtained from owners of 28 of the treated cattle. Surgery was successful in eliminating all clinical signs in 25 of the 28 cattle. There was an increased risk of upward fixation of the patella associated with Brahman and Brahman-type cattle, compared with non-Brahman cattle.
Pathologic correlations with magnetic resonance images of osteochondrosis lesions in canine shoulders
Authors: van Bree Henri , Degryse Hendrik , Van Ryssen Bernadette , Ramon Frank , Desmidt Mick
Published: December 2023

Twelve shoulders in 6 dogs with clinical and radiographic evidence of osteochondrosis were examined by magnetic resonance imaging performed on a 0.5-T superconductive system. Scans were obtained with 5-mm-thick slices and 0.75-mm pixel size. Unenhanced T1-weighted spin-echo and unenhanced T2*-weighted gradient-echo images were obtained, using a high-resolution surface coil. The T1-weighted sequences were repeated after iv injection of 0.1 mmol of gadopentetate dimeglumine/kg of body weight (0.2 ml/kg). In 6 joints, histologic examination of synovia and articular cartilage was carried out.

The magnetic resonance images were correlated with arthrographic, arthroscopic, and histologic findings. Magnetic resonance imaging was useful in evaluating the extent of subchondral lesions and the severity of inflammatory changes within the subchondral bone. Areas of low signal (visible subchondrally on T1-weighted images that were enhanced by administration of contrast medium) indicated active inflammatory changes within the subchondral bone. Although articular cartilage discontinuity could be detected, loose cartilage flaps could not always be reliably demonstrated. Signal inhomogeneity within the articular cartilage was presumed to correspond with zones of cartilage degeneration.
Virus-induced maternal reproductive failure of swine
Authors: Mengeling William L. , Paul Prem S. , Lager Kelly M.
Published: December 2023

The following article, “Virus-induced maternal reproductive failure of swine,” was prepared by Dr. Mengeling and his colleagues in response to our request that he provide a concise overview of some of what is presently known about this subject, especially in regard to events of the past 10 years. A lot has happened during this interval. For example, about a decade ago, the JAVMA published a report titled, “Farm studies of porcine parvovirus injection” (JAVMA, Mar15, 1983, pp 592–594). On the basis of this and other information available at the time, it was clear that porcine parvovirus (ppv) was an important reproductive pathogen for swine; however, the development of a vaccine for ppv-induced reproductive failure just a few years before suggested that the clinical impact of ppv soon would be minimized. It appears that this expectation has been realized, at least in part. What was not, and could not be, predicted, however, was that a new virus with devastating effects on swine reproduction would suddenly appear to counterbalance some of the gains made in the control of ppv. The new virus, now called porcine reproductive and respiratory syndrome virus, is currently prevalent throughout the major swine-producing areas of this country. In their article, Drs. Mengeling, Paul, and Lager focus mainly on the viruses, including porcine reproductive and respiratory syndrome virus, that are most often associated with maternal reproductive failure in swine in the United States, with special emphasis on information regarding control and diagnosis that would be of value to veterinarians in clinical practice.
Prognosis after surgical excision of cerebral meningiomas in cats: 17 cases (1986–1992)
Authors: Gallagher Jack G. , Berg John , Knowles Kim E. , Williams Leslie L. , Bronson Roderick T.
Published: December 2023

Long-term follow-up information was obtained for 17 cats with cerebral meningiomas treated by surgical excision. Three cats died or were euthanatized in the immediate postoperative period: 2 cats, because of brain herniation and 1 cat, because of acute renal failure. In the remaining 14 cats, most clinical signs resolved within 1 week of surgery. Three cats (21.4%) had confirmed or presumed local tumor recurrence. Two of these cats developed recurrent neurologic signs, and died or were euthanatized at 3 and 9 months, respectively, after surgery. One cat was euthanatized for an unrelated problem 72 months after surgery, and on postmortem examination, had a recurrent meningioma at the surgery site. The remaining 11 cats (78.6%) did not develop evidence of local tumor recurrence within follow-up periods ranging from 18 to 47 months (median, 27 months).
Planning for emergencies
Authors: Seibert Philip J.
Published: December 2023

In this, the fourth and final article in his series on compliance with Occupational Safety and Health Administration regulations, Mr. Seibert discusses the requirements for emergency action and fire prevention plans.—Kurt J. Matushek, Assistant Editor.
Selection of Quarter Horses affected with hyperkalemic periodic paralysis by show judges
Authors: Naylor Jonathan Μ.
Published: December 2023

Thirty offspring of a Quarter Horse sire, affected by hyperkalemic periodic paralysis (hpp), were examined electromyographically. On the basis of the detection of or lack of spontaneous activity with high frequency myotonic or pseudomyotonic discharges, the horses were diagnosed as being affected (14 horses) or unaffected (16 horses) with hpp. The show performance of these horses was evaluated for the first 3 to 9 years of their life by use of American Quarter Horse Association records. Horses affected with hpp performed significantly (P < 0.01) better in halter classes than did unaffected horses; mean halter points for the 2 groups were 11.9 and 0.4, respectively. The mean total performance points were not significantly different. None of the offspring had a successful racing record.