Ultrasonographic diagnosis of pyelonephritis in a cow

A 2-year-old Holstein cow was examined because of a 2-month history of anorexia, decreased milk production, and a white vaginal discharge. Results of physical, laboratory, and ultrasound examinations were consistent with pyelonephritis. Through ultrasound examination, the right kidney and ureter were identified as structurally involved. Right nephrectomy was performed. Eight months after nephrectomy, the cow was clinically normal. In this cow, ultrasonography helped to determine disease severity, to direct the course of treatment, and to improve the accuracy of diagnosis and prognosis.

Concurrent infections of Giardia and Cryptosporidium on two Ohio farms with calf diarrhea

Giardia and Cryptosporidium infections were diagnosed by immunofluorescence assay on two Ohio dairy farms with calf diarrhea problems. On the first farm, all nine diarrheic calves sampled once in June had Giardia cysts in their feces. On the second farm, all five diarrheic calves examined at the beginning of the diarrhea outbreak in March had Giardia infection. When resampled, the overall infection rate of normal and diarrheic calves was 82.4% in April, and 40.0% in August after the diarrhea subsided. Positive calves ranged from 11 to 164 days of age, and 22.2% of them were as young as 1 to 3 weeks of age. Eight of nine diarrheic calves (88.8%) on the first farm had Cryptosporidium infection. Lower infection rates (< 30%) were found on the second farm. Six of 10 positive calves were 11-22 days old, three were 164-177 days old, and one was 71 days old. Five of these 10 positive calves were also positive for Giardia infection. Five diarrheic calves on the northern Ohio farm and one diarrheic calf on the central Ohio farm were treated with metronidazole after failing to respond to antibiotic therapy. Clinical improvement was observed in all calves within 48 h after the start of treatment. The high Giardia infection rates and intensities in calves of a wide age range and the clinical response to metronidazole suggest that Giardia infection contributed to the outbreaks of diarrhea.

Isolation of Mycobacterium paratuberculosis from mononuclear cells in tissues, blood, and mammary glands of cows with advanced paratuberculosis

Seven mature dairy cows from 6 herds were obtained with history, clinical signs of disease, and laboratory findings suggestive of advanced paratuberculosis. A surgically implanted collection chamber was used to obtain peripheral tissue fluid. Blood, mammary gland flush fluid, and collection chamber flush fluid (CCFF) samples were obtained 6 times over a 2-week period from each cow. Mononuclear cell-rich portions of these fluids obtained by gradient centrifugation were submitted for bacteriologic culture of Mycobacterium paratuberculosis and for total and differential cell counts. Bacteriologic culture of feces for M paratuberculosis and complete necropsy performed on each cow at the conclusion of the study confirmed the diagnosis of paratuberculosis. Numbers of tissue macrophages obtained from CCFF samples were lower than expected. Mean (+/- SD) differential count of tissue macrophages collected from CCFF was 65.57 (+/- 23.39). Mean calculated tissue macrophages (total cell count x differential count) collected from CCFF samples was 623.1 (+/- 784.55) cells/microliters. Mycobacterium paratuberculosis was isolated from 1 of 42 (2.4%) collections of mononuclear cell-rich portions of plasma and from 2 of 42 (4.8%) CCFF samples. Mycobacterium paratuberculosis was not isolated from any collections of mammary gland flush fluid. The collection and processing techniques used in this study did not enhance detection of M paratuberculosis infection in cows with advanced paratuberculosis, beyond that of ileocecal lymph node biopsy or fecal culture.

Diagnosis of Cryptosporidium on a sheep farm with neonatal diarrhea by immunofluorescence assays

An outbreak of diarrhea in neonatal lambs occurred on a sheep farm in northern Ohio. Diarrhea commenced as early as 1 week of age and lasted for about 3-4 days. Although 100% of the newborn lambs were affected, most had recovered by 3 weeks of age. Cryptosporidium infection appeared to be the cause of diarrhea. Fecal examination of nine diarrheic newborn lambs (5-10 days old), 23 older lambs (2-3 weeks old, six with diarrhea) and 23 clinically normal ewes by immunofluorescence assays revealed infection rates of 100%, 78.3% and 17.4%, respectively. Most newborn lambs had high oocyst counts. Ewes were considered to be an important source of infection for lambs.

Serodiagnosis of paratuberculosis in sheep by use of agar gel immunodiffusion

An agar gel immunodiffusion (AGID) test was used over a 3-year period to examine 1,871 serum samples from sheep representing 5 Mycobacterium paratuberculosis-infected flocks and 4 flocks presumed to be uninfected. Of 1,032 sheep, 31 had positive AGID test results (scoring 1 to 5), and 23 of these 31 were necropsied. Infection with M paratuberculosis was confirmed by 1 or more of the following findings: observation of typical lesions on histologic examination of sections of ileum or ileocecal lymph nodes, observation of clumps of acid-fast bacteria in mucosal smears of ileum, and isolation of the organism from feces or tissue. False-positive results on AGID testing were not found in sheep from flocks known to have exposure to Corynebacterium pseudotuberculosis. Diarrhea in infected sheep was observed infrequently; chronic, severe weight loss was the most common sign observed. On histologic examination of tissues from 20 infected sheep, 16 (80%) had diffuse lesions of the ileum and 13 (65%) had acid-fast bacteria in areas of ileal inflammation; 4 had discrete granulomas and peripheral lymphocytic infiltrates in the ileum. Sheep with diffuse lesions tended to have higher mean scores on AGID testing and examination for acid-fast bacteria, compared with those from sheep with more discrete lesions. Bacteriologic culture yielded M paratuberculosis from only 3 sheep with paratuberculosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Abomasal luminal pressure in cattle with abomasal volvulus or left displaced abomasum

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 cut-off 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.

Risk factors for abomasal volvulus and left abomasal displacement in cattle

A hospital-based case-control study was conducted to evaluate and compare risk factors for abomasal volvulus (AV) and left displaced abomasum (LDA) in cattle. Medical record abstracts were derived from 17 North American veterinary schools by the Veterinary Medical Data Program for all cattle admitted between Jan 1, 1977 and Dec 31, 1986, and for those with a diagnosis of AV or LDA. From a total of 108,956 individual cattle records, 1,036 cases of AV and 7,695 cases of LDA were identified, with a ratio of LDA to AV cases of 7.4 to 1. In-hospital mortality was 23.5% for AV and 5.6% for LDA. Age, breed, gender, and season each had significant (P less than 0.05) effects on risk for AV and LDA. Risk for AV and LDA increased with increasing age, with greater risk in cattle aged 4 to 7 years. Dairy cattle were at higher risk of developing AV (adjusted odds ratio, 36.4) and LDA (adjusted odds ratio, 95.2) than were beef cattle. The odds of AV in Brown Swiss cattle were significantly (P less than 0.0001) lower, and the odds of LDA in Guernsey cattle were significantly (P less than 0.0001) higher than those in Holstein cattle. Female cattle were also at higher risk of developing AV (adjusted odds ratio, 3.3) and LDA (adjusted odds ratio, 29.1) than were male cattle. The odds of AV and LDA varied considerably throughout the year, with the lowest number of cases observed in autumn. Seasonal development of AV differed significantly (P less than 0.0001) from that of LDA, with the odds of AV and LDA being highest in January and March, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Prognostic value of surgical and postoperative findings in cattle with abomasal volvulus

A prospective study evaluating the prognostic value of surgical and postoperative findings in 80 cattle with abomasal volvulus was performed. Surgical correction of abomasal volvulus was performed in all animals. After surgery, cattle were categorized into 3 groups: productive (acceptable milk production or appetite, n = 59), salvaged (poor milk production or appetite, n = 10), and nonsurvivors (n = 11). Cattle with omasal-abomasal volvulus had a significantly (P less than 0.005) worse prognosis than cattle without omasal involvement. Large abomasal fluid volume, venous thrombosis, and blue or black abomasal color before decompression were all indicative of a poor prognosis. Most cattle had poor or fair appetites the first day after surgery; productive animals had marked improvement in appetite over the next 3 days. All cattle observed to have a good appetite within 3 days after surgery were later determined to be productive animals. The heart rate decreased in all groups after surgery; however, tachycardia (heart rate greater than 80 beats/min) was sustained in cattle that were later salvaged for slaughter. Diarrhea was observed after surgery in 54% of cattle. The duration of diarrhea was significantly shorter (P = 0.009) in productive cattle than in salvaged and nonsurviving cattle. The presence or absence of diarrhea was only of predictive value when considered in conjunction with the estimated abomasal fluid volume.

Pharmacokinetics of rifampin in adult sheep

Pharmacokinetics and bioavailability of rifampin in adult sheep were investigated by use of high-performance liquid chromatography for determination of serum concentrations. Eight adult ewes were given rifampin PO at the rate of 50 mg of rifampin/kg of body weight. Three weeks after the first experiment, the sheep were given rifampin PO and IV at the rate of 20 mg/kg in a cross-over design, with 1 week between treatments. Serum obtained over a 36-hour period was analyzed for rifampin and a potential metabolite, 25-desacetyl-rifampin, using reverse-phase chromatography with UV detection at 254 nm. Data were analyzed by compartmental and noncompartmental models. Analysis by the noncompartmental model of rifampin serum concentrations after IV administration yielded a mean +/- SD total body clearance of 1.16 +/- 0.21 ml/min/kg, apparent volume of distribution at steady state of 0.45 +/- 0.06 L/kg, and terminal elimination rate constant of 0.15 +/- 0.04 hour-1. The harmonic mean of the elimination half-life was 4.56 hours. Because of incomplete and continuing absorption, bioavailability was extremely variable after oral administration. Desacetyl-rifampin was not detected. On the basis of pharmacokinetic values, serum concentrations measured in this study, and published minimal inhibitory concentrations, the dosage of 20 mg of rifampin/kg, PO, every 24 hours should provide adequate serum concentrations for treatment of rifampin-susceptible bacterial infections in sheep.

Gastritis induced by Helicobacter pylori in gnotobiotic piglets

Helicobacter pylori has recently been recognized as a gastric pathogen in humans. Experimental oral inoculation of gnotobiotic piglets with this organism results in gastritis that exhibits many features of the corresponding disease in humans. In piglets the organism is restricted to the gastric microenvironment and persists in that location despite prompt humoral and cellular responses to antigens of H. pylori. The gnotobiotic piglet model is useful for delineation of the role of suspected bacterial virulence factors (i.e., motility and urease production) in gastric colonization and for preclinical determination of the efficacy of various antimicrobial substances.

Preoperative prognostic indicators in cattle with abomasal volvulus

A prospective study evaluating preoperative prognostic indicators in 80 cattle with abomasal volvulus was done. Surgical correction of the abomasal volvulus was performed in all animals. After surgery, cattle were categorized into 3 groups: productive (acceptable milk production or appetite, n = 59), salvaged (poor milk production or appetite, n = 10), and nonsurvivors (n = 11). Mean values for study variables did not differ significantly between salvaged and nonsurvivor groups. Cattle in these 2 groups were combined to form a nonproductive group, which was compared with the productive group. Productive cattle had a significantly lower preoperative heart rate than nonproductive cattle, were less dehydrated, had lower serum alkaline phosphatase (ALP) activity and serum creatinine concentration, more frequent rumen contractions, higher serum Na+ and Cl- concentrations, and had been inappetent for a shorter period. Significant differences were not detected in blood pH, base excess, anion gap, PCV, and serum K+ concentrations between the 2 groups. Feces from nonproductive cattle tended to be reduced in volume and were significantly darker. A number of preoperative prognostic indices were evaluated by calculating the sensitivity, specificity, and positive predictive value (+PV) of each variable and by using logistic regression. Positive predictive values were generally higher in identifying productive cattle than nonproductive cattle.(ABSTRACT TRUNCATED AT 250 WORDS)

Excision of neoplasms of the bovine lower eyelid by H-blepharoplasty

Neoplasms of the lower eyelid in 14 cattle were treated by wide surgical excision and H-blepharoplasty. Healing was by first intention, and cosmetic results were satisfactory in all cases. Lid function was satisfactory in 12 cattle, and there was no evidence of recurrence after at least 6 months in 12 cattle. This therapy can be recommended for large infiltrative masses on the lower lid if there is no evidence of bony involvement, metastasis, or involvement of both puncta at the medial canthus.

Jejunal mucosal lactase activity from birth to three weeks in conventionally raised calves fed an electrolyte solution on days 5, 6 and 7 instead of milk

The purpose of this study was to evaluate the effect of withdrawal of lactose from the diet for 72 hours on lactase activity in the jejunal mucosa of conventionally raised calves. The descending portion of the duodenum of six Holstein calves less than 24 hours old was cannulated. The calves were fed milk except on days 5, 6 and 7 when they were given the same volume of an electrolyte solution. Sequential biopsy specimens of the proximal jejunal mucosa were obtained for three weeks and the lactase activity determined. Lactase activity was highest on day 1 and a trend toward decreased lactase activity from birth until three weeks was observed. Mean lactase activity was significantly (p less than 0.05) higher for days 1, and 3 compared to days 9, 13 and 17. The withdrawal of milk and replacement by an electrolyte solution during three days had no significant effect on jejunal mucosal lactase activity in neonatal calves.

Clinical and electrocardiographic characterization of cattle with atrial premature complexes

Atrial premature complexes (APC) were identified in 16 cows over a 2-year period. Fourteen cows had concurrent gastrointestinal disease. Variation in the intensity of the first heart sound and an occasionally irregular heart rhythm were evident during thoracic auscultation. Neither cardiac murmurs nor pulse deficits were detected in any cows, and clinical signs of heart failure were lacking. Three cows had APC immediately prior to or after development of atrial fibrillation. The heart rate when APC were diagnosed ranged from 48 to 124 beats/min (mean, 77 +/- 20 beats/min), and the APC frequency ranged from less than 1 to 23/min (mean 9.4 +/- 8.0). The P-wave morphologic characteristics in 4 cows with APC was abnormal. The coupling index of the APC varied between 0.44 and 0.95, with a mean of 0.73. Aberrant ventricular activation was usually associated with a short coupling interval (coupling index less than 0.60) and was observed in 3 cows. Ten cows were determined to be hypocalcemic and 4 cows hypokalemic when APC were identified. Atrial ectopic activity could not be detected in 12 cows after resolution of the concurrent gastrointestinal disorder or electrolyte abnormality. Atrial premature complexes may be a functional cardiac disorder in cattle, unrelated to structural heart disease. The potential for APC to progress to sustained atrial arrhythmias such as atrial fibrillation should be considered.

The etiology and surgical management of tracheal collapse in calves

The mean ages of 10 calves with tracheal collapse were 2.7 weeks at onset of clinical signs and 9.4 weeks at presentation for treatment. Inspiratory and expiratory dyspnea and stunted growth were the most common clinical signs. There were abnormalities of the cranial ribs consistent with healing fractures with redundant callus in eight lateral thoracic radiographs. Tracheal collapse in calves may result from cranial thoracic trauma during or soon after birth. Short polypropylene ring prostheses made from 60 ml syringe barrels were placed on the tracheas of four calves with cervical tracheal collapse. There were cranial rib masses in all calves and resection of the right first and second ribs was necessary in one calf to allow placement of prostheses. Dyspnea was relieved in all calves. One calf died of unrelated causes in year 3, and one calf had recurrence of clinical signs at month 5 and was euthanatized. In both calves, tracheal stenosis resulted from continued growth and infolding of the trachea within the constraints of the prostheses. One calf was alive at month 11, and one calf died of acute bronchopneumonia on day 2. Removal of tracheal prostheses in calves is recommended after 2 to 3 months if clinical signs recur.

Repair of anomalous nasolacrimal duct in a bull by use of conjunctivorhinostomy

A proximal nasolacrimal duct anomaly, believed to be congenital, in a bull was repaired by use of conjunctivorhinostomy. Initial attempts at correction, using prolonged nasolacrimal duct catheterization, were unsuccessful. Trephination from the medial canthus to the ventral nasal meatus, combined with long-term catheterization of this new passage, was successful in resolving clinical signs of disease.

Renal excretion of creatinine, electrolytes, protein, and enzymes in healthy sheep

Urinary indices of renal function and damage were measured in 6 healthy, mature ewes over a 48-hour period. Endogenous creatinine clearance, total and fractional electrolyte excretion rates, protein excretion, urine volume, and urine gamma-glutamyltransferase and beta-glucuronidase activities were measured. Significant variations in the excretion rates of creatinine, electrolytes, and protein were not found between intervals within the 48-hour urine collection period. Total urinary electrolyte excretion rates were significantly (P less than 0.001) correlated with fractional electrolyte excretion rates normalized for creatinine concentration; however, coefficient of determination was low.

Abomasal volvulus in cattle following correction of left displacement by casting and rolling

Seven adult cows developed abomasal volvulus immediately following correction of left displacement by casting and rolling. Three cows were rolled to provide temporary relief from left displaced abomasum because of concurrent disease and 4 were rolled as the principal therapy for left displacement. In each animal surgical correction of abomasal volvulus was accomplished via right paralumbar fossa celiotomy and inclusion of an omentopexy during abdominal closure. Surgery was performed within 24 hours of casting and rolling. All 7 cows recovered after surgery and were reported to have satisfactory milk production and appetite 6 weeks later.

Jejunal mucosal lactase activity from birth to 3 weeks in conventionally raised calves

The descending portion of the duodenum of 6 Holstein calves less than 24 hours old was cannulated. Sequential biopsy specimens of the proximal jejunal mucosa were obtained every other day for 3 weeks. Lactase activity in the mucosal specimens was determined and was highest at day 1, but decreased with age. Mean lactase activity was significantly (P less than 0.05) higher for days 1, 3, 5, and 7, compared with days 19 and 21.

Tarsal fractures in a heifer and a bull

Tarsal fractures were diagnosed in a heifer and a bull. In both cases, radiography confirmed intra-articular fractures, with subluxation of the fracture fragment. Sudden, nonreducible hock flexion was a clinical sign in both cases. This sign may be highly suggestive of intra-articular fracture when diagnosis must be made without radiography.

Atresia coli in calves: 26 cases (1977-1987)

Atresia coli was identified in 26 calves. In calves with abdominal distension, progressive depression, and the absence of feces since birth, atresia coli should be suspected. Surgery was performed on 24 calves, involving decompression of the distended large intestine followed by colonic anastomosis. Nine calves were subsequently discharged; 3 of those calves reached breeding age. As an adult, 1 of the calves produced 5 offspring unaffected by atresia coli. Early postoperative mortality was associated with hypothermia, peritonitis, and ischemic necrosis of the large intestine. Calves with visible signs of peritonitis at surgery had a poor prognosis. Four calves had motility disturbances of the colon after surgery. These were characteristic of a functional obstruction and were unresponsive to treatment. Surgery was most successful in calves that were bright, alert, and ambulatory.

Bovine fetal infection with Mycobacterium paratuberculosis

In utero transmission of Mycobacterium paratuberculosis, the causative agent of paratuberculosis in cattle, has been suggested. Tissue specimens were obtained at a packing plant from pregnant dairy cows and their fetuses and from cows with clinical signs of paratuberculosis and from their fetuses. Specimens were processed according to methods described for isolating M paratuberculosis from bovine tissues and were incubated on Herrold egg yolk medium for 16 weeks. Presumed positive specimens were confirmed to be M paratuberculosis, using acid-fast staining and subculturing. Of 407 lymph nodes from cows, 34 (8.4%) were culture positive for M paratuberculosis; 9 of 34 (26.4%) of these culture-positive cows had fetuses from which specimens were also culture positive. The results estimated the risk of fetal infection with M paratuberculosis to be 26.4% (95% confidence interval between 11.3 and 40.7%).

Idiopathic gonitis in heifers: 34 cases (1976-1986)

Acute suppurative arthritis of the stifle joint was diagnosed in 34 Holstein heifers between 1976 and 1986. Only 1 stifle joint was affected in each heifer; however, 1 heifer also had involvement of the contralateral radiocarpal joint. In each heifer, there was marked lameness and synovitis characterized by an effusion with high synovial fluid nucleated cell counts and total protein concentration. Seventy-four percent (25/34) of the heifers had radiographic evidence of an osteolytic lesion involving the lateral tibial plateau. Bacteriologic cultures of synovial fluid, synovial membrane, and bone yielded no growth. Eighteen of 23 (78%) affected heifers for which follow-up data was obtained became productive herd members after treatment.

Comparison of naturally occurring proximal duodenal obstruction and abomasal volvulus in dairy cattle

Physical and clinicopathologic findings from six cows with proximal duodenal obstruction (PDO) and 58 cows with abomasal volvulus (AV) were compared retrospectively. Many of the physical signs were similar in cows with PDO and cows with AV, but the two conditions differed in the type of abdominal distention, and in the findings from rectal examination and abdominal auscultation. Cows with PDO had significantly lower mean values for serum sodium (Na+) and chloride ion (Cl-), and higher mean values for plasma bicarbonate [HCO3-], base excess, carbon dioxide pressure (pCO2), serum phosphate, urea nitrogen, and total protein than AV affected cattle. Cows with PDO showed hyperglycemia (range, 263-990 mg/dl; mean, 618 mg/dl) of unexplained etiology that was significantly higher than blood-glucose concentrations in AV cows (mean, 178 mg/dl). Although all AV cows with anion gap values greater than 32 mEq/l died;PDO cows with equally elevated anion gap survived. The anion gap elevations in PDO and AV cows resulted from accumulation of different anions. Although the site of obstruction of aborad flow of ingesta is similar in both disease conditions, the differences in physical and clinicopathologic findings appear to reflect differences in the degree of reticulo-omasal orifice obstruction and the degree of abomasal vascular compromise.