bluuebunny/crossref_metadata_2025 huggingface dataset:
Immunodeficiency syndrome associated with wasting and opportunistic infection in juvenile llamas: 12 cases (1988-1990)
Authors: Hutchison Jennifer M. , Garry Franklyn B. , Johnson LaRue W. , Quackenbush Sandra L. , Getzy David M. , Jensen Wayne A. , Hoover Edward A.
Published: December 2023

Immunodeficiency was diagnosed as the cause of severe debilitating disease characterized by weight loss, failure to grow, and persistent infections that failed to respond to treatment in 12 young llamas. The llamas were affected after maternal-acquired immunity had decreased; failure of passive transfer of immunoglobulins thus was not suspected. Areas of lymph nodes containing T lymphocytes were hypocellular, suggesting T-cell involvement. High serum immunoglobulin concentrations were not found, despite the existence of infectious disease, suggesting at least secondary B-cell involvement. Results of lymphocyte blastogenesis assays were suggestive of B- and T-cell involvement. It was not possible to determine whether the condition was inherited or acquired.
Milk antimicrobial drug residue assay results in cattle with experimental, endotoxin-induced mastitis
Authors: Tyler Jeff W. , Cullor James S. , Erskine Ronald J. , Smith Wayne L. , Dellinger Jon , McClure Kim
Published: December 2023

Antimicrobial drug residue testing was performed on milk samples obtained from 8 cows with experimental endotoxin-induced mastitis, using 4 commercially available assay kits. Although none of the cows in the study received antimicrobials, only 1 of the 4 assay procedures, assay C, had consistently negative results (specificity = 1.00). The proportion of positive assay results varied from 0 to 1.00 among combinations of sampling time, sample status (endotoxin-infused quarter vs composite noninfused sample). The proportion of positive results found when assay C was used (0) differed significantly from the proportion found when the 3 other assays were used. The proportion of positive results did not differ significantly between assay A (0.45) and assay B (0.48); however, both assays had a significantly lower proportion of positive assays than did assay D (0.86).

Logistic regression models were developed predicting positive milk antimicrobial drug residue assay results as a function of assay kit, sample status, and time interval following experimental challenge exposure. Using assay A as a baseline risk, assay B and assay D were more likely to have positive assay results, and assay C had a decreased risk of positive assay results. Milk samples from endotoxin-infused quarters were at increased risk for positive assay results, compared with noninfused composite samples. Samples collected from endotoxin-infused quarters or control quarters were at increased risk for positive assay results following the intramammary infusion of endotoxin. Our findings suggest that specificity of milk antimicrobial drug residue assays varies greatly among assay kits and that intramammary inflammation may increase the proportion of false-positive assay results.
Penile hematoma in bulls: 60 cases (1979-1990)
Authors: Musser Jeffrey M. B. , St-Jean Guy , Vestweber Jerome G. , Pejsa Thomas G.
Published: December 2023

Sixty bulls with penile hematomas were examined from 1979 through 1990. Thirty-eight bulls underwent surgical correction, 17 bulls were managed by medical treatment, and 5 bulls were not treated. Hereford and Polled Hereford breeds represented the majority (n = 37, 62%) of the bulls, with 10 other breeds representing the remainder (n = 21, 35%) in this study; breed was not reported in 2 bulls. Follow-up information was obtained from owners (40/60) through conversation on the success or failure of treatment, interval of sexual rest, duration of breeding soundness, and final outcome of the bull. Surgical correction was successful in 19 (70%) of 27 cases; medical treatment was successful in 6 (46%) of 13 cases. Of the 8 bulls that had penile hematomas with swelling measuring > 20 cm in width, 6 were successfully treated surgically, compared with 1 of 3 successfully treated medically. Of the bulls with penile hematomas having a swelling measuring ≤ 20 cm in width, 7 of 9 were successfully treated surgically, compared with 4 of 5 successfully treated medically. Duration of the penile hematoma had little effect on the success of surgical correction. Of the bulls allowed sexual rest for > 2 months after treatment was initiated, 6 (25%) of 24 had a recurrence of penile hematoma. Four (40%) of 10 bulls allowed sexual rest for ≤ 2 months had a recurrence of penile hematoma.
Systemic necrotizing vasculitis in nine young Beagles
Authors: Scott-Moncrieff J. Catharine R. , Snyder Paul W. , Glickman Lawrence T. , Davis Erica L. , Felsburg Peter J.
Published: December 2023

A systemic necrotizing vasculitis of unknown etiopathogenesis may be termed juvenile polyarteritis syndrome (jps). The syndrome has been recognized primarily in young Beagles used for toxicologic studies. We studied 9 young Beagles with jps. Affected dogs had fever (40 to 41.5 C), anorexia, and signs of pain in the cervical area. They had a characteristic hunched stance, and were unwilling to move. Laboratory abnormalities in all dogs included nonregenerative anemia, hypoalbuminemia, and leukocytosis characterized by a mature neutrophilia. Analysis of csf revealed a moderate to severe neutrophilic pleocytosis and a mildly high protein concentration in most dogs. Signs of disease resolved rapidly with high doses (2.2 mg/kg of body weight, po) of prednisone. If untreated, clinical signs and laboratory abnormalities had a remitting and relapsing course in most dogs. Findings at necropsy included necrotizing arteritis with fibrinoid necrosis, periarteritis, thrombosis, and intimal proliferation that most frequently affected small- to medium-sized vessels in the cervical spinal cord, mediastinum, and heart. An immune-mediated pathogenesis for this disease is suspected.
Abomasal luminal pressure in cattle with abomasal volvulus or left displaced abomasum
Authors: Constable Peter D. , St-Jean Guy , Koenig Gerard R. , Hull Bruce L. , Rings D. Michael
Published: December 2023

The abomasal luminal pressure was determined during surgery in 54 dairy cows with abomasal volvulus (av) and another 50 dairy cows with left displaced abomasum. The luminal pressure was high in all cattle with av and 49 (98%) cattle with left displaced abomasum. Luminal pressure was significantly higher in cattle with av (median, 11.7 mm of Hg; range, 4.1 to 32.4 mm of Hg) than cattle with left displaced abomasum (median, 8.7 mm of Hg; range, 3.5 to 20.7 mm of Hg). Among cattle with av, abomasal luminal pressure was significantly higher in cattle that died or were sold for slaughter following surgery (median, 20.6 mm of Hg; n = 8) than in cattle that were retained in the herd (median, 11.0 mm of Hg; n = 46). The luminal pressure was weakly correlated with the preoperative serum alkaline phosphatase activity but not correlated with duration of inappetence before surgery. Calculation of likelihood ratios and construction of a response operating characteristic curve for cattle with av indicated that a cutoff value of 16 mm of Hg for luminal pressure optimized the distribution of cattle into productive and nonproductive groups. The sensitivity, specificity, positive predictive value, and negative predictive value of a luminal pressure < 16 mm of Hg in predicting a productive outcome were 0.83, 0.75, 0.95, and 0.43, respectively.
Stress reactions and stress fractures of the proximal palmar aspect of the third metacarpal bone in horses: 58 cases (1980-1990)
Authors: Pleasant R. Scott , Baker Gordon J. , Muhlbauer Michael C. , Foreman Jonathan H. , Boero Michael J.
Published: December 2023

The case records, radiographs, and nuclear bone scans of 58 horses with stress reactions or stress fractures of the proximal palmar aspect of the third metacarpal bone (MC3) were reviewed. There were 47 Standardbreds, 4 Quarter Horses, 3 Thoroughbreds, 2 Arabians, 1 Oldenburg, and 1 Pony of America. Fifty-six of the horses were racehorses or performance horses. The mean and median ages of affected horses were 4 and 3 years, respectively. Lameness ranged from mild to severe. Physical findings were usually subtle and included signs of pain on deep palpation of the proximal palmar aspect of MC3 and slight effusion of the middle carpal joint in some cases. Lameness was commonly improved by high palmar and palmar metacarpal nerve blocks or anesthesia of the middle carpal joint. Fifty-three horses had higher than normal radiopharmaceutical uptake in the proximal palmar aspect of MC3 in the left or right limb. The other 5 horses had higher than normal radiopharmaceutical uptake bilaterally. Fifty-six of the 63 limbs with abnormal bone scans also had abnormal radiographs. Treatment consisted of a variable period of rest (1 to 6 months). Healing was best assessed by follow-up bone scans. Of the 45 horses for which follow-up information was adequate, 29 (64%) returned to their previous level of performance.
Development of chronic renal disease in cats fed a commercial diet
Authors: DiBartola S. P. , Buffington C. A. , Chew D. J. , McLoughlin M. A. , Sparks R. A.
Published: December 2023

Chronic renal failure was observed in 10 young adult client-owned cats that had been fed 1 commercial cat food exclusively since weaning. The diet contained 40% protein and 0.32% potassium on a dry matter basis, and phosphoric acid was added during production. We attempted to determine whether exclusive feeding of this diet would induce clinical and laboratory evidence of renal dysfunction in clinically normal adult cats. Over a 2-year study, 3 of 9 of these cats developed clinical and laboratory evidence of renal dysfunction and renal lesions. Two additional cats developed renal lesions, but had normal laboratory values. The renal lesions consisted of lymphoplasmacytic interstitial nephritis and interstitial fibrosis. We concluded that chronic renal disease may develop in clinically normal adult cats fed diets high in protein and acid content, but marginally replete in potassium.
Vaporizer in circle for delivery of isoflurane to dogs
Authors: Bednarski Richard M. , Gaynor James S. , Muir William W.
Published: December 2023

An in-circuit vaporizer for delivery of isoflurane was evaluated. The isoflurane concentration within an isolated circle breathing circuit was determined for 1 hour in 6 in-the-circuit vaporizers with the wicks removed. A mechanical ventilator and artificial lung were connected to the circuit. Isoflurane concentration increased as vaporizer setting increased, and delivered concentration (%) at 60 minutes ( ± sem) ranged from 0.46 ± 0.10 at tap setting 1 to 3.67 ± 0.30 at setting 5. Temperature of the isoflurane did not change.

Cardiovascular and respiratory function were maintained within a clinically acceptable range in 6 dogs anesthetized with thiamylal and maintained with 1.87% end-tidal isoflurane delivered from the in-circuit vaporizer during spontaneous ventilation, controlled ventilation, and closed-circuit anesthesia. The range of vaporizer tap settings ( ± sem) was lower during closed-system anesthesia (2.5 ± 0.1 to 3.5 ± 0.6) and during controlled ventilation (2.6 ± 0.2 to 3.3 ± 0.2) than during semi-closed system anesthesia (5.4 ± 0.3 to 6.8 ± 0.4).

The in-circuit vaporizer was used to deliver isoflurane to 36 dogs anesthetized for a variety of surgical and medical procedures. Ventilation was spontaneous, assisted, and in 1 instance, controlled. Cardiovascular function, respiratory function, and recovery times were within clinically acceptable ranges. The initial vaporizer tap setting ( ± sem) was 8.2 ± 0.4, and this corresponded to an end-tidal isoflurane concentration of 3.5 ± 0.6. The range of vaporizer settings during the maintenance phase ( ± sem) was 2.8 ± 0.5 to 4.6 ± 1.9. This corresponded to an end-tidal isoflurane concentration of 1.2 ± 0.1 to 1.8 ± 0.1%.

This study documents that when appropriate guidelines are followed and limitations understood, the in-circle vaporizer is suitable for delivery of isoflurane to dogs undergoing a variety of surgical and medical procedures. Guidelines include removal of the wick, attention to the relatively rapid increase of anesthetic depth during the first 5 minutes of anesthesia, and the need to decrease the setting of the vaporizer control lever if assisted or controlled ventilation is used, or if closed system flow rates are used. Limitations include unpredictability of output with changing ambient temperature and difficulty adapting its use with semi-open breathing systems such as the t-piece or Bain coaxial circuit.
Effect of subclinical infection with Actinobacillus pleuropneumoniae in commingled feeder swine
Authors: Rohrbach B. W. , Hall R. F. , Hitchcock J. P.
Published: December 2023

Sequential serologic analysis for Actinobacillus pleuropneumoniae was done on 240 commingled feeder swine at 1 and 21 days after purchase and at slaughter. At the beginning of the experiment, mean weight of the pigs was 18.6 kg, and the pigs were maintained to a mean slaughter weight of 109.95 kg. A fourfold increase in antibody titer against Actinobacillus pleuropneumoniae was demonstrated in 28 (12%) pigs. Mean adjusted rate of gain for infected pigs was 0.74 ± 0.10kg/d and 0.77 ± 0.09kg/d for uninfected pigs. Differences in feed efficiency were not detected between infected and uninfected pigs. Our findings suggested that 5.64 additional days are required for pigs with subclinical infection to reach market weight of 113.6 kg, compared with that for uninfected herdmates. A vaccination program to prevent subclinical infection may not be cost effective.
Hyphema associated with retinal disease in dogs: 17 cases (1986-1991)
Authors: Nelms Susan R. , Nasisse Mark P. , Davidson Michael G. , Kirschner Susan E.
Published: December 2023

We evaluated the medical records of 17 dogs with hyphema of presumed retinal origin to evaluate the clinical, laboratory, ultrasonographic, and histologic features as well as known complications. The mean age of the dogs was 11.5 years. Routine hematologic and biochemical evaluation failed to identify an underlying cause in any dog. Retinal detachments, however, were identified in 10 of 13 dogs evaluated by ultrasonography and 5 of 6 globes evaluated histologically. In 1 dog, hyphema was associated with retinal vascular disease, presumed to be caused by hypertension. The prognosis for vision in geriatric dogs with hyphema, secondary to retinal disease, was found to be grave, as 10 dogs developed secondary glaucoma. The outcome for all dogs was loss of vision.
Hyperadrenocorticism associated with adrenocortical tumor or nodular hyperplasia of the adrenal gland in ferrets: 50 cases (1987-1991)
Authors: Rosenthal Karen L. , Peterson Mark E. , Quesenberry Katherine E. , Hillyer Elizabeth V. , Beeber Neal L. , Moroff Scott D. , Lothrop Clinton D.
Published: December 2023

Adrenocortical adenoma, nodular hyperplasia, or carcinoma was diagnosed in 50 ferrets. Thirty-five (70%) ferrets were female and 15 (30%) were male. The mean age at which clinical signs were first noticed was 3.4 years (range, 1 to 7 years). Clinical signs included large vulva (n = 31; 89% of females), alopecia (n = 43; 86%), pruritus (n = 20; 40%), and increased consumption of water and increased urine output (n = 4; 8%). A mass was palpated at the cranial pole of the kidney during physical examination of 17 (34%) ferrets. Ultrasonography, performed on 39 of 50 ferrets, revealed a unilateral adrenal gland mass in 19 (49%). Four ferrets were anemic, and 2 ferrets were thrombocytopenic. Baseline plasma concentrations of cortisol and corticosterone were within or below the reference range in all 17 ferrets tested, whereas baseline plasma estradiol concentrations were high in 4 of the 11 ferrets (36%) tested. After adrenocorticotropic hormone (acth) administration, only 1 ferret had a slightly exaggerated response on the basis of plasma cortisol concentrations, and all 17 had normal responses on the basis of plasma corticosterone concentrations. There was little or no increase in plasma estradiol concentrations after acth administration. Of the 50 ferrets, 39 were treated by adrenalectomy. Unilateral adrenalectomy was performed in 34 ferrets in which 1 adrenal gland was large, whereas subtotal bilateral adrenalectomy was performed in 5 ferrets with bilateral adrenal disease. Five ferrets died in the immediate postoperative period, and follow-up information was available for the remaining 34, 1 to 34 months after surgery. A decrease in vulvar size was generally noticed by 2 days after surgery, and complete hair regrowth was noticed by 2 months.

Because clinical signs resolved after adrenalectomy, it was likely that the adrenocortical tumors and nodular hyperplasias of the adrenal gland were hyperfunctional. However, these ferrets did not have excessively high circulating concentrations of cortisol. At present, we recommended that diagnosis of adrenocortical disease in ferrets be made on the basis of characteristic clinical signs, results of abdominal ultrasonography, and finding large adrenal glands during surgery. Results of acth stimulation tests, with determination of plasma cortisol or corticosterone concentrations, were of no value in the diagnosis.
Granulomatous hepatitis in dogs: Nine cases (1987–1990)
Authors: Chapman Barbara L. , Hendrick Mattie J. , Washabau Robert J.
Published: December 2023

Granulomatous hepatitis (gh) is an uncommon histopathologic diagnosis in dogs. On the basis of clinical reports, fungal infections appear to be the most common cause of gh in dogs, but many other potential causes have been identified. The medical records and histopathologic findings for 9 dogs with gh were reviewed to identify additional specific causes of gh in dogs. Diseases associated with gh included intestinal lymphangiectasia (n = 2), lymphosarcoma (n = 1), histiocytosis (n = 1), dirofilariasis(n = 1), and histoplasmosis (n = 1). In 1 dog, no other disease process was identified. Of the remaining 2 dogs, 1 had concurrent granulomatous pneumonitis of unknown cause, and the other had periportal hepatitis and temporal muscle wasting. All 9 dogs with gh had clinical evidence of liver disease, such as hepatomegaly, icterus, and ascites, or had high serum alkaline phosphatase and alanine aminotransferase activity. Because of the wide variety of potential causes of gh in dogs, an accurate diagnosis should be sought so that appropriate treatment can be chosen and an accurate prognosis given.
Use of a DNA-based test for the mutation associated with porcine stress syndrome (malignant hyperthermia) in 10,000 breeding swine
Authors: O’Brien Peter James , Shen Hua , Cory C. Robert , Zhang Xia
Published: December 2023

To test the hypothesis that the mutation associated with porcine stress syndrome (pss; malignant hyperthermia) was present in a large proportion of North American and English swine, a simple and rapid laboratory protocol was used for cost-effective, large-scale diagnosis of susceptibility to pss. This pss test was applied to 10,245 breeding swine of various breeds from 129 farms in the United States, Canada, and England. Approximately 1 of 5 swine was a heterozygous carrier of the pss mutation, with approximately 1% being homozygotes. Prevalence of the pss mutation was 97% for 58 Pietrain, 35% for 1,962 Landrace, 15% for 718 Duroc, 19% for 720 Large White, 14% for 496 Hampshire, 19% for 1,727 Yorkshire, and 16% for 3,446 crossbred swine. The pss gene frequencies for these breeds were 0.72, 0.19, 0.08, 0.10, 0.07, 0.10, and 0.09, respectively. In addition to these breeds, we have identified the pss mutation in Poland China and Berkshire breeds. These gene frequencies were 30 to 75% lower in Canadian swine than in US swine, with the exception of Yorkshires, for which the gene frequency was threefold higher in Canadian swine. English swine were similarly, or more so, affected than were US swine. Accuracy was estimated at > 99%. Cost to perform the test was < $20/ animal. Depending on the perceived net balance of deleterious and beneficial effects of the mutation, the pss test could be used to eradicate the pss mutation from herds, or for controlled expression of the mutation.
Chronic mitral valve disease in Cavalier King Charles Spaniels: 95 cases (1987–1991)
Authors: Beardow Andrew W. , Buchanan James W.
Published: December 2023

Systolic heart murmurs caused by chronic mitral valve disease are particularly common in Cavalier King Charles Spaniels (ckcs) in Great Britain. To determine if American-bred ckcs have a similar high prevalence of chronic valve disease, results of stethoscopic examinations on 394 ckcs were analyzed. Left apical systolic heart murmurs were found in 22% of the dogs. The prevalence ranged from 9% in dogs < 1 year old to 100% in those ≥ 10 years old; prevalence was 56% in dogs ≥ 4 years old. Differences were not found in prevalence between sexes and among various coat colors. Reexamination of 79 dogs after 1 year revealed an incidence of new murmurs of 21%. Comparison of ages at initial examination in 128 referral hospital cases with chronic mitral valve disease revealed a mean age of 6.25 years in 17 ckcs, in contrast to a mean age of 12 years in other breeds. Echocardiographic and necropsy findings indicated that ruptured chordae tendineae and mitral valve prolapse are major components in the chronic valve disease process in ckcs.
Effects of bilateral ovariectomy via colpotomy in mares: 23 cases (1984–1990)
Authors: Hooper R. Neil , Taylor Tex S. , Varner Dickson D. , Blanchard Terry L.
Published: December 2023

Postoperative performance and behavioral patterns were investigated retrospectively in 23 client-owned mares after bilateral ovariectomy via colpotomy. The interval from surgery to postoperative inquiries ranged from 9 to 67 months. Information obtained from review of the medical record and client interviews included the reason for ovariectomy, postoperative complications, problems identified by owners after discharge of the mare from the hospital, postoperative level of athletic performance, postoperative signs of estrus, and overall owner satisfaction. Reasons given by owners for having mares ovariectomized were behavioral modification (16 mares), use as embryo-transfer recipients (3 mares), use as mount mares for collecting semen (2 mares), elimination of chronic colic during estrus (1 mare), and sterilization for registration (1 mare). Postoperative complications developed in 4% (1/23) of the mares; however, problems were noticed by the owners of 4 other mares after discharge from the hospital. Continuing signs of behavioral estrus were detected in 35% (8/23) of the mares, but in only in 9% (2/23) was the behavior judged to be objectionable by the owner. Of 12 mares used in performance events prior to bilateral ovariectomy, 10 were judged to be competing at greater than preoperative levels, 1 was judged to be competing at the same level, and 1 was judged to be competing at less than preoperative level of performance. Of 18 owners, 14 were satisfied, 2 were undecided, and 2 were dissatisfied with their mare after it had had bilateral ovariectomy.
Displacement of the tendon of the superficial digital flexor muscle in dogs: 10 cases (1983–1991)
Authors: Mauterer John V. , Prata Raymond G. , Carberry Carol A. , Schrader Steven C.
Published: December 2023

Displacement of the tendon of the superficial digital flexor muscle was diagnosed in 9 dogs (10 tarsi). Four of 10 displacements occurred in Shetland Sheepdogs. All dogs had an acute onset of lameness with swelling over the proximal end of the tuber cal-canei. Lateral displacement occurred in 8 tarsi and medial displacement in 2 tarsi. Nonsurgical treatment (exercise restriction, bandaging, and administration of anti-inflammatory medication) was ineffective in the 5 dogs in which it was attempted. Surgical reconstruction of the supporting soft tissues resulted in return to normal function in 9 cases available for follow-up evaluation.
Small-intestinal volvulus in cattle: 35 cases (1967–1992)
Authors: Anderson David E. , Constable Peter D. , Jean Guy St. , Hull Bruce L.
Published: December 2023

Medical records of 35 cattle with small-intestinal volvulus were reviewed. Surgical correction was performed on 32 cattle, and 17 of these cattle were discharged from the hospital. Mean duration of clinical signs for survivors was not significantly different from that for nonsurvivors, and the most commonly recorded clinical signs were abdominal pain, anorexia, lethargy, abdominal distention, and dehydration. Physical examination of cattle with intestinal volvulus revealed tachycardia, tachypnea, and nor-mothermia. Rectal examination findings included distended small intestine, scant feces or mucus, and tight bands coursing dorsoventrally in the middle portion of the abdomen. Clinicopathologjc testingre-vealed azotemia, hypocalcemia, hyperglycemia, and leukocytosis with a left shift. Nonsurvivors had significantly lower mean preoperative venous blood phi and mean base excess and higher mean serum potassium concentration than did survivors.

A diagnosis of volvulus of the entire small intestine was made during surgery in 25 cattle, whereas volvulus of the distal jejunum and ileum was diagnosed during surgery in 7 cattle. Survival rate following surgical correction of volvulus of the entire small intestine (44%) was not significantly different from survival rate following surgical correction of volvulus of the distal jejunum and ileum (86%). However, survival rate for dairy cattle (63%) was significantly higher than survival rate for beef cattle (22%).

To determine potential risk factors for the development of small-intestinal volvulus, epidemiologic data from cattle admitted to veterinary teaching hospitals throughout North America were collected by searching records entered into the Veterinary Medical Data Base. Between 1967 and 1991, 190 of 242,745 cattle had small-intestinal volvulus. Surgical correction was performed in 130 cattle, and 75 cattle were discharged from the hospital Among cattle seen at veterinary teaching hospitals, dairy cattle had an increased risk of developing small-intestinal volvulus, compared with beef cattle, and cattle > 7 years old had a decreased risk, compared with cattle < 2 months old. Female cattle were more likely to suffer from intestinal volvulus than were male cattle.
Isolation of multiple Salmonella serovars from a dairy two years after a clinical salmonellosis outbreak
Authors: Gay J. M. , Hunsaker M. E.
Published: December 2023

Samples were obtained for bacteriologic culturing of salmonellae from cows and calves on, and the environment of, a large California dairy that used free-stall housing and a flush system for manure handling. Two years previously, the dairy had an outbreak of clinical salmonellosis in the lactating herd; however, since that time, it had not had problems with clinical salmonellosis. On the basis of mean annual milk production per cow, this dairy was consistently ranked in the top 25% of dairies in the area enrolled in the Dairy Herd Improvement Association. Results of bacteriologic culture of 76% (108/142) of environmental samples and 48% (639/1,339) of fecal samples were positive for salmonellae. Eighty-two percent of the isolates were serovar C1, subclassified as Salmonella montevideo, and 17% were serovar E. Results of bacteriologic culture of 85% of samples of recycled flush water being pumped into the free-stall alleys were positive, as were results of bacteriologic culture of 78% of samples of herd bulk milk filters, 97% of fecal samples collected from calves being fed nonsalable milk, and 25% of fecal samples collected from cows at the time of breeding. These findings suggest that freedom from clinical salmonellosis and comparatively high measures of herd performance do not indicate the absence of salmonellae from a premises, and that hardy infectious agents transmitted by ingestion of feces can become established in the environment of modern free-stall dairies that use recycled water in their manure flush systems.
Histologically confirmed clinical toxoplasmosis in cats: 100 cases (1952–1990)
Authors: Dubey J. P. , Carpenter James L.
Published: December 2023

Tissue sections from 119 cats that died or were euthanatized (1952-1990) because of toxoplasmosis-like illness were reexamined for Toxoplasma gondii by direct microscopy and immunohistochemical staining with anti-T gondii serum. Clinical and pathologic data from 100 of these cats with histologically verified toxoplasmosis were then analyzed. Of these 100 cats, 36 were considered to have generalized toxoplasmosis, 26 predominantly pulmonary lesions, 16 abdominal, 2 hepatic, 1 pancreatic, 1 cardiac, 2 cutaneous, 7 neurologic, and 9 had neonatal toxoplasmosis. In 14 cats, concurrent microbial infections or other maladies were seen. Cats were 2 weeks to 16 years old (median, 2 years; mean, 4 years). Sixty-five cats were males and 34 were females; sex was not recorded for 1 cat. Of 67 cats that had rectal temperatures recorded, 49 (73%) had fever (40.0 to 41.7 C). Dyspnea, polypnea, and signs of abdominal discomfort were frequently observed. Toxoplasmosis had been confirmed antemortem in 8 cats; 4 had a serum antibody titer to T gondii of ≥ 1:1,024; and T gondii had been found in cytologic evaluation of tracheal aspirates from 2 cats and pleural fluid from 1 cat, as well as in a biopsy specimen of a mesenteric lymph node from another. Of the 15 cats with T gondii serum-antibody titers determined by the Sabin-Feldman dye test, 6 had no antibody detected in 1:4 dilution of their serum. Indirect fluorescent antibody titers were found in 10 of 10 cats' sera tested. Forty-one eyes from 27 of the cats were examined microscopically. Twenty-two of the 27 cats (81.5%) had evidence of intraocular inflammation in one or both eyes. Multifocal iridocyclochoroiditis was the most common lesion and was seen in 18 (81.8%) of the cats with ophthalmitis. The ciliary body was the most often severely affected portion of the uvea. Of the 22 cats with ocular toxoplasmosis, T gondii was found in eyes of 10. Toxoplasma gondii was found in the retina of 5 cats, the choroid of 2, the optic nerve of 1, the iris of 3, and the ciliary body of 4. Toxoplasma gondii was identified in 80% of 55 brains, 70.0% of 90 livers, 76.7% of 86 lungs, 64.4% of 45 pancreata, 62.7% of 59 hearts, 45.8% of 72 spleens, 41.5% of 65 intestines, 17.7% of 61 kidneys, and 60.0% of 30 adrenal glands.
Comparison of microbiologic culture, an enzyme-linked immunosorbent assay, and determination of somatic cell count for diagnosing Staphylococcus aureus mastitis in dairy cows
Authors: Hicks Cathleen R. , Eberhart Robert J. , Sischo William M.
Published: December 2023

Results of using microbiologic culture of a single milk sample, determination of somatic cell count (scc), an elisa, and a combination of determination of scc and elisa to diagnose Staphylococcus aureus mastitis in dairy cattle were compared. Cows were considered to have S aureus intramammary infections if microbiologic culture of at least 2 of 3 consecutive sets of milk samples yielded growth of the organism. Data were analyzed from milk samples collected over a 4-month period from 185 cows in 5 herds. Sensitivity, specificity, and likelihood ratio of a positive test result for microbiologic culture of a single milk sample were 93%, 99%, and 93.0, respectively. Sensitivity, specificity, and likelihood ratio of a positive test result for elisa were 69%, 61%, and 1.8, respectively, and for determination of scc, they were 79%, 72%, and 2.9, respectively. Combination of determination of scc and elisa had sensitivity, specificity, and likelihood ratio of a positive test result of 80%, 62%, and 3.4, respectively. Results from microbiologic culture of consecutive milk samples were more consistent than results of elisa performed on consecutive samples. These data suggest that microbiologic culture of a single milk sample is the best of the 3 tests studied for diagnosing S aureus intramammary infection.
Inflammatory response to clostridial vaccines in feedlot cattle
Authors: Stokka Gerald L. , Edwards A. J. , Spire M. F. , Brandt R. T. , Smith J. E.
Published: December 2023

In 24 individually housed feedlot steers that weighed 275 kg, clostridial vaccines were compared for size of injection site reactions, systemic inflammatory response caused by vaccination, and impact on feed consumption. Vaccines were a bacterin/toxoid containing antigens from multiple clostridial species (7-way), and a Clostridium perfringens type C and D toxoid; sterile physiologic saline solution was used as the control.

Injection site reactions were observed in all vaccinated cattle. Differences in size of lesions were found, with cattle given the 7-way vaccine (7-way group) having the largest lesions. The inflammatory response to vaccination, measured by serum concentration of the acute-phase protein haptoglobin, was significantly (P < 0.05) increased in both vaccinated groups over that of controls. However, the 7-way group had higher postinjection values than did the group given type C and D toxoid. The 7-way group had a significant (P < 0.05) 20% decrease in feed consumption in response to the second injection of vaccine. These findings are indicative of potential negative effects of multiple clostridial vaccinations.
Histologically low-grade, yet biologically high-grade, fibrosarcomas of the mandible and maxilla in dogs: 25 cases (1982-1991)
Authors: Ciekot Phyllis A. , Powers Barbara E. , Withrow Stephen J. , Straw Rodney C. , Ogilvie Gregory K. , LaRue Susan Μ.
Published: December 2023

Medical records of 25 dogs with histologically low-grade fibrous masses of the maxilla and mandible were reviewed. Most of the dogs had extensive clinical histories and had had previous biopsies of the affected regions, from which specimens were often interpreted as benign fibrous connective tissue. The most common breed represented was Golden Retriever (13/25 dogs, 52%). Skull radiographs were evaluated for 22 dogs, and 16 dogs (72%) had evidence of bone lysis. At admission, none of the dogs had radiographic evidence of pulmonary metastasis. On subsequent examinations and necropsy, prevalence of pulmonary metastasis was 12% (3/25 dogs) and of regional lymph node metastasis, 20% (5/25 dogs). Histologic appearance of all specimens was similar and was characterized by proliferation of fibrous connective tissue, with moderate to low cellularity, that aggressively infiltrated adjacent normal tissue. Treatment modalities varied considerably. Surgical excision in combination with radiation therapy, surgery alone, radiation therapy alone, and radiation therapy used adjunctly with localized hyperthermia prolonged survival times in some dogs. The clinical signs, tumor behavior, and histologic characteristics of these lesions were distinctive from those in previously described oral fibrosarcomas in dogs. Comparatively, these tumors most closely resembled aggressive fibromatoses in human beings in regard to clinical signs, local invasive behavior, and histologic appearance, but differed in the prevalence of metastasis.
Hypothyroidism in dogs: 66 cases (1987-1992)
Authors: Panciera David L.
Published: December 2023

Sixty-six dogs with hypothyroidism were identified from dogs examined over a 5-year period. Hypothyroidism was diagnosed only if the dog had a low, resting serum thyroxine concentration and serum thyroxine concentration was not higher than the lower limits of the reference range 6 hours after iv administration of bovine thyrotropin.

The prevalence of hypothyroidism was 0.2%. Neutering was determined to be the most significant gender-associated risk factor for development of hypothyroidism. Neutered male and spayed female dogs had a higher relative risk of developing hypothyroidism than did sexually intact females. Sexually intact females had a lower relative risk. Breeds with a significantly increased risk, compared with other breeds, were the Doberman Pinscher and Golden Retriever. The most common clinical findings were obesity (41%), seborrhea (39%), alopecia (26%), weakness (21%), lethargy (20%), bradycardia (14%), and pyoderma (11 %). Low voltage R-waves were found, on 58% of ecg. Clinicopathologic abnormalities included hypercholesterolemia (73%), nonregenerative anemia (32%), high serum alkaline phosphatase activity (30%), and high serum creatine kinase activity (18%). Serum total triiodothyronine concentrations were within reference ranges in 15% of the hypothyroid dogs. Response to treatment was good in most dogs, but those with severe concurrent disease or neurologic abnormalities were less likely to respond with complete resolution of clinical signs.
Diagnosis of freemartinism in cattle: The need for clinical and cytogenic evaluation
Authors: Zhang Tingqing , Buoen Lance C. , Seguin Bradley E. , Ruth George R. , Weber Alvin F.
Published: December 2023

A total of 727 blood samples from female calves born co-twin to male calves were examined cytogenetically for freemartinism between 1978 and 1992. Six hundred calves (82.5%) were determined to be freemartins, and 127 (17.5%) were determined not to be freemartins. The percentage of calves determined not to be freemartins was substantially higher than the 8% reported for an unselected population of female co-twins. We concluded that some obvious freemartins were eliminated prior to submission of samples for confirmatory cytogenetic diagnosis, and that only a small percentage of the estimated 93,000 female calves born co-twin to male calves annually are so examined. Therefore, probably a large number of female co-twins that are not truly freemartins are sold to slaughter every year. We propose that obvious freemartins be identified by use of the vaginal-length test and that the remaining clinically questionable calves be differentiated cytogenetically. This combination of procedures could prevent unnecessary economic losses and preserve important genetic material.

Three animals with chromosomal anomalies were found during examination of samples for freemartinism. Cytogenetic evaluation for freemartinism thus offers the added value of simultaneous surveillance for cytogenetic aberrations in male and female cells of a sample.
Characterization of infection with endemic porcine reproductive and respiratory syndrome virus in a swine herd
Authors: Stevenson G. W. , Van Alstine W. G. , Kanitz C. L.
Published: December 2023

Infection of 8-week-old pigs with endemic porcine reproductive and respiratory syndrome (PRRS) virus was detected on a farm that had an epidemic of PRRS in 1989. During the 2.5 years since the original epidemic, reproductive performance of the breeding herd had been within acceptable limits, but mortality had periodically exceeded one-fourth of the pigs in the nursery (195 died of 761 weaned, 25.6%). Investigators attempted to determine the age and humoral immune status of pigs infected with endemic PRRS virus on the farm.

Serum obtained from 9 groups of 1- to 18-week-old pigs (10 pigs/group) was examined for PRRS virus by virus isolation. Serum was obtained from 8 sows that had farrowed within the preceding 24 hours. Serum from the sows was obtained weekly until litters were weaned at 3 weeks of age. Serum was obtained from 27 newborn pigs (3 to 4 newborn pigs from each of the 8 sows) prior to intake of colostrum and at weekly or biweekly intervals until the pigs were 20 to 21 weeks of age. Isolation of PRRS virus and indirect fluorescent antibody serologic testing were performed on these serum samples. In another study, serum was obtained for serologic testing from 10 sows in each of 6 parity groups.

The PRRS virus was isolated from serum of only 3- to 12-week-old pigs. The 8 sows and their 27 pigs were seronegative for PRRS virus during the 3-week lactation period. By 10 weeks of age, 18 of the 27 suckling pigs were still alive and had seroconverted (titers ≥ 1:20). Titers peaked at 13 to 14 weeks of age (range, 1:640 to 1: ≥ 2,560). The prevalence of seropositive sows of all parities was 9 of 60 (15%).

Pigs in the nursery and grower were the major reservoir for PRRS virus in the herd of this report. Pigs became infected with PRRS virus in the nursery through contact with older pigs that were infected with PRRS virus, and were not infected by in utero or postpartum exposure to sows infected with PRRS virus. Virus circulation in pigs of finishing age and in the breeding herd was minimal. Although all pigs had been viremic and were seropositive for PRRS virus by 9 to 10 weeks of age, 4 of 18 (22%) were seronegative by 20 to 21 weeks of age, indicating titer decay and reversion to seronegative status can develop within 10 weeks.
Excretion of porcine reproductive and respiratory syndrome virus in semen after experimentally induced infection in boars
Authors: Swenson Sabrina L. , Hill Howard T. , Zimmerman Jeff J. , Evans Lawrence E. , Landgraf John G. , Wills Robert W. , Sanderson Thomas P. , McGinley Michael J. , Brevik Andy K. , Ciszewski Dan K. , Frey Merwin L.
Published: December 2023

Four boars intranasally inoculated with porcine reproductive and respiratory syndrome (PRRS) virus were monitored for 56 days after exposure for changes in semen characteristics and for the presence of virus in the semen. Clinically, 2 of 4 boars had mild respiratory signs of 1 day's duration after infection. Changes in appetite, behavior, or libido were not detected. All boars seroconverted on the indirect fluorescent antibody and serum virus neutralization tests by day 14 after inoculation. Virus was isolated from serum between days 7 and 14 after inoculation. During the monitoring period, semen volume decreased and pH correspondingly increased; however, this change began 7 to 10 days prior to infection. Differences in sperm morphologic features, concentration, or motility between the preinfection and postinfection samples were not observed. The PRRS virus was detected in semen at the first collection in each of the 4 boars (ie, 3 or 5 days after challenge exposure). Virus was detected in nearly all semen samples collected from the 4 infected boars through days 13, 25, 27, and 43, respectively. Neither gross nor microscopic lesions attributable to PRRS virus were observed in tissues collected at the termination of the experiment (day 56), and virus isolation results from reproductive tissues were negative.
Potential risk factors for Cryptosporidium infection in dairy calves
Authors: Garber L. P. , Salman M. D. , Hurd H. S. , Keefe T. , Schlater J. L.
Published: December 2023

Fecal samples from 7,369 calves on 1,103 farms were examined for cryptosporidia in a nationwide survey, using monoclonal antibody technique. Cryptosporidium oocysts were found in calves from 652 (59.1%) of the farms and in 1,648 (22.4%) of the tested calves. Almost half the calves between 7 and 21 days of age had cryptosporidia in their fecal samples. Prevalence was highest during the summer. Farms with multiple-cow maternity facilities and farms with > 100 milking cows were the most likely to have calves with cryptosporidia.
Effects of short- and long-term administration of phenobarbital on endogenous ACTH concentration and results of ACTH stimulation tests in dogs
Authors: Dyer Karen R. , Monroe William E. , Forrester S. Dru
Published: December 2023

The effects of short-term phenobarbital administration were evaluated in 6 adult mixed-breed dogs that received phenobarbital (5 mg/kg of body weight, PO, q 12 h) for 8 consecutive weeks. Six additional dogs served as untreated controls. At 2-week intervals, endogenous adrenocorticotropic hormone (ACTH) concentration and cortisol concentration before and 2 hours after administration of porcine aqueous ACTH (2.2 IU/kg, M) were measured. By means of oneway ANOVA, we were not able to detect a significant (P ≥ 0.05) difference in endogenous ACTH concentration and cortisol concentration before and after exogenous ACTH administration within groups over time or between groups at any time.

To evaluate effects of long-term phenobarbital administration, sera and plasma were collected from 5 epileptic dogs that had received phenobarbital for > 2 years and had serum phenobarbital concentrations > 20 μg/dl. Endogenous ACTH concentration and cortisol concentration, before and after administration of ACTH, were within established reference ranges for all 5 dogs.

Together, these results suggest that phenobarbital administration alone does not affect endogenous ACTH concentration or response to exogenous ACTH administration in dogs, and that these may be valid screening tests for hyperadrenocorticism in most dogs receiving phenobarbital.
Infiltrative lipoma in dogs: 16 cases (1981–1992)
Authors: Bergman Philip J. , Withrow Stephen J. , Straw Rodney C. , Powers Barbara E.
Published: December 2023

Medical records of 15 dogs with infiltrative lipoma, 1 of which had 2 lesions, were reviewed. Median age of affected dogs was 6.0 years, and median weight was 30.5 kg. The ratio of females to males was 4:1. Eight of the dogs were Labrador Retrievers. In 8 dogs, the lesions had previously been excised. There was not any apparent site predilection. Excision was the only treatment in all 15 dogs, and follow-up information was available for all dogs. Two dogs, each of which had 1 tumor, were euthanatized immediately after surgery, because the tumor could not be completely excised. Of the remaining 14 tumors, 5 (36%) recurred. Median time to recurrence for these 5 tumors was 239 days (range, 96 to 487 days). By means of Kaplan-Meier analysis, the percentage of dogs disease free 1 year after surgery was calculated to be 67%.
Evaluation of butorphanol and cyproheptadine for prevention of cisplatin-induced vomiting in dogs
Authors: Moore Antony S. , Rand William M. , Berg John , L'Heureux Deborah A. , Dennis Robinette A.
Published: December 2023

Cisplatin was administered at a dosage of 50 mg/m2 of body surface to 69 dogs with various neoplasms. Dogs were randomly assigned to receive antiemetics according to 1 of the following 5 protocols: group 1, no antiemetic (control, n = 45 treatments); group 2, 0.4 mg of butorphanol/kg of body weight (n = 52 treatments); group 3, 0.2 mg of butorphanol/kg (n = 19 treatments); group 4, 2 mg of cyproheptadine/kg (n = 48 treatments); and group 5, 1 mg of cyproheptadine/kg (n = 10 treatments). Randomization was performed for each dog prior to each treatment. Butorphanol was administered im immediately after completion of cisplatin infusion. Cyproheptadine was given orally 12 to 14 hours before and again immediately before cisplatin administration. The proportion of dogs that vomited in group 1 was 40 of 45 (89%). Butorphanol at a dosage of 0.4 mg/kg proved highly effective in preventing cisplatin-induced vomiting, reducing the proportion of dogs that vomited (10/52, 19%) compared with the control group.