Effect of intrauterine dextrose or antibiotic therapy on reproductive performance of lactating dairy cows diagnosed with clinical endometritis

The objectives of this study were to assess the responses to treatments (clinical cure and cow survival 14 d posttherapy) of cows with clinical endometritis (CE) that received intrauterine infusion of a hypertonic solution of 50% dextrose (DEX) or subcutaneous ceftiofur crystalline free acid (CCFA) and subsequent pregnancy per artificial insemination (P/AI) in cows with CE compared with cows without CE. Cows (n=760) from 2 dairy herds were screened for CE using vaginoscopy and measurement of cervix diameters [exam 1; 26±3 d in milk (DIM)]. Cows with vaginal discharge scores of 2 or 3 (scale 0-3) were stratified by parity and randomly allocated into 1 of 3 treatment groups: (1) intrauterine infusion (∼200 mL) of 50% DEX solution (n=79); (2) 6.6 mg/kg single-dose of subcutaneous administration of CCFA (n=75); or (3) untreated control animals (CON, n=83). Fourteen days posttherapy (at 40±3 DIM), cows with CE were re-examined (exam 2; 40±3 DIM) to assess the response to treatments. All cows were presynchronized with 2 injections of PGF(2α) given 14 d apart (starting at 26±3 DIM) followed by Ovsynch (OV; GnRH-7 d-PGF-56 h-GnRH 16 h-timed-AI) 12 to 14 d later. Cows displaying signs of standing estrus any time during the protocol were inseminated, whereas the remaining cows were subjected to timed AI 16 h after the second GnRH of OV. Pregnancy diagnosis was performed via transrectal ultrasonography at 39±3d post-AI followed by pregnancy reconfirmation 30 d after the first pregnancy diagnosis. Uterine swabs revealed that Arcanobacterium pyogenes and Escherichia coli were the most predominant bacteria isolated at the time of treatments. Mortality within 14 d posttherapy was not different among treatment groups. Cows with CE had greater cervical diameter at exam 1 and decreased P/AI compared with cows without CE. Treatment with CCFA or DEX increased the proportion of cows with clear vaginal discharge (score 0; clinical cure) 14 d posttherapy compared with CON cows. Pregnancy per AI from DEX (29.8±4%) cows tended to differ from that of CON (21.1±4%) or CCFA cows (19.7±4%), but it resulted in similar P/AI as those cows without CE (39.1±2%). The use of intrauterine DEX alone or as an adjunct of antibiotic therapy for the treatment of CE needs further investigation.

Serum haptoglobin-matrix metalloproteinase 9 (Hp-MMP 9) complex as a biomarker of systemic inflammation in cattle

A reliable and specific test that discriminates between acute neutrophil activation and chronic inflammatory disease may be useful in clinical decision making in a variety of conditions encountered in veterinary medical practice. An ELISA specific for neutrophil-derived haptoglobin-matrix metalloproteinase 9 (Hp-MMP 9) complexes was used to determine serum concentrations of Hp-MMP 9 and was compared to ELISA assays for Haptoglobin (Hp) and matrix metalloproteinase 9 (MMP 9) in 15 animals with acute sepsis, 10 animals with chronic inflammatory or metabolic disease and 10 healthy cows. Animal disease classifications were completed prior to the determination of serum concentrations of the 3 proteins. Duration of illness, disease process and lesions observed at necropsy were used to place animals into a specific classification. The serum MMP 9 concentrations in healthy cows differed significantly from those measured in sera of acutely septic and chronically ill animals. Serum haptoglobin concentrations in healthy cows were negligible when compared to animals with acute septic or chronic diseases. There was substantial overlap in MMP 9 and Hp concentrations between acute and chronic disease animals. In contrast, serum concentrations of Hp-MMP 9 complexes found almost exclusively in sera from acutely septic animals but not in chronically ill and normal cattle. The Hp-MMP 9 ELISA may be the serological test of choice in the determination of systemic inflammation associated with bacterial sepsis.

Validation of a commercially available immunoassay for the measurement of bovine cardiac troponin I

BACKGROUND

Commercially available cardiac troponin I (cTnI) assays developed for use in humans have not yet been validated for use in cattle.

HYPOTHESES

The ADVIA Centaur TnI-Ultra immunoassay can be used for the detection of bovine cTnI. In healthy cattle, serum cTnI is undetectable or is present only in trace amounts.

METHODS

Purified bovine cTnI and cTnI-free bovine serum were used for the evaluation of assay performance including intra- and inter-assay precision, sensitivity, interference, linearity, and recovery. Effects of storage at 23, 4, -20, and -80 degrees C for 2 days, and at -20 and -80 degrees C for 7 and 14 days and repeated freeze-thaw cycles on recovery of cTnI were analyzed. Serum cTnI concentrations in 30 healthy dairy cows were determined.

RESULTS

Intra- and inter-assay precisions (mean +/- SD) were 4.48 +/- 2.26 and 13.36 +/- 6.59%, respectively. The assay demonstrated linearity at 0.5, 2, 15, and 30 ng/mL cTnI. Mean recovery was 100.81, 85.26, 87.72, and 114.42%, respectively. Skeletal muscle homogenate added to serum of known cTnI concentration did not alter the concentration of the analyte (P > .05). Concentration of cTnI significantly decreased when samples were stored at 4 and 23 degrees C for 2 days (P < .05). Repeated freeze-thaw cycles and storage at -20 degrees C for 7 days had no significant influence on cTnI concentration (P > .05). Serum cTnI concentration in healthy cattle was <or=0.03 ng/mL.

CONCLUSION AND CLINICAL IMPORTANCE

ADVIA Centaur can be used reliably for the detection of serum cTnI concentration in cattle.

Hematuria and transitional cell papilloma of the renal pelvis treated via unilateral nephrectomy in an alpaca

CASE DESCRIPTION

An 11-year-old 72-kg (158-lb) sexually intact female alpaca was examined for diagnosis and treatment of hematuria of 4 months' duration.

CLINICAL FINDINGS

Pigmenturia was detected by the owner when the alpaca was 8 months pregnant. Radiographic, ultrasonographic, vaginal speculum, and cystoscopic evaluation of the urinary tract revealed normal vaginal and urethral epithelia and increased bladder vessel tortuosity, with pulses of hemorrhage from the left ureter. Regenerative anemia and mild leukopenia were detected and serum urea nitrogen and creatinine concentrations were within reference ranges.

TREATMENT AND OUTCOME

Chronic hematuria resolved after unilateral nephrectomy of the left kidney, and no dysfunction was detected in the remaining kidney. Histologic evaluation of the kidney revealed a transitional cell tumor in the renal pelvis.

CLINICAL RELEVANCE

Although anemia is common in South American camelids, hematuria is an uncommon sign of this condition. Chronic urinary tract infection, toxin ingestion, and neoplasia causing hematuria or hemoglobinuria should be considered in South American camelids with pigmenturia. Thorough and systematic evaluation of the urinary tract should be performed to locate the site of hemorrhage to treat hematuria appropriately.

Mycoplasma hyopneumoniae bacterins and porcine circovirus type 2 (PCV2) infection: induction of postweaning multisystemic wasting syndrome (PMWS) in the gnotobiotic swine model of PCV2-associated disease

Groups (5 to 15 per group) of gnotobiotic swine were infected oronasally with porcine circovirus type 2 (PCV2) at 3 days of age and then given 1 of 6 different commercial Mycoplasma hyopneumoniae (M. hyopneumoniae) bacterins as either a single dose (7 d of age, 1 application products) or 2 doses (7 and 21 d of age, 2 application product). Control groups received PCV2 alone (n = 9) or were infected with PCV2 and immunized twice with keyhole limpet hemocyanin (KLH) emulsified in incomplete Freund's adjuvant (ICFA) (n = 7). Five of 7 (71%) PCV2-infected piglets immunized with KLH/ICFA developed mild or overt PMWS, whereas none of 9 piglets infected with PCV2 alone developed PMWS. Five of 12 (42%) piglets vaccinated with a commercial bacterin containing mineral oil adjuvant developed PMWS following vaccination. None of the PCV2-infected piglets in the other bacterin-vaccinated groups developed PMWS in this model of PCV2-associated disease. This difference in prevalence of PMWS in piglets given the mineral oil-adjuvanted M. hyopneumoniae bacterin and the other M. hyopneumoniae bacterin vaccination groups was statistically significant (P < 0.05).

Experimental induction of bacterial gastritis and gastric ulcer disease in gnotobiotic swine inoculated with porcine Helicobacter-like species

OBJECTIVE

To determine whether 2 isolates of recently isolated swine-origin Helicobacter pylori-like bacteria are pathogenic in pigs and compare the signs of gastric disease induced by these isolates with those detected in H pylori- and Helicobacter heilmannii-infected pigs.

ANIMALS

36 neonatal gnotobiotic pigs.

PROCEDURE

Groups of separately housed pigs were inoculated orally with swine-origin Helicobacter-like isolates 2662 or 1268, H pylori (human gastric pathogen), or a gastric homogenate from gnotobiotic swine containing H heilmannii. Noninoculated pigs were used as control animals. Clinical signs and development of homologous and heterologous antibodies against Helicobacter organisms were assessed. After euthanasia, gastric tissues were examined grossly and microscopically; Helicobacter organisms were detected by use of Warthin-Starry and immunohistochemical stains.

RESULTS

Both porcine Helicobacter-like isolates colonized the stomachs of swine. Isolate 2662 was highly pathogenic; in 13 isolate 2662-inoculated pigs, gastroesophageal ulcerations developed in 9 and ulceration of the gastric glandular mucosa was detected in 5. Histologically, inflammatory gastritis consisting of multifocal to diffuse lymphocytic and plasmacytic cellular infiltrates and lymphoid follicle formation in the gastric lamina propria accompanied bacterial colonization of the gastric compartment. In contrast, H heilmannii was minimally pathogenic in that only modest inflammatory cell infiltrates were seen. Gastroesophageal or mucosal ulcers were not evident in pigs inoculated with H heilmannii.

CONCLUSIONS AND CLINICAL RELEVANCE

These data indicate that swine-origin H pylori-like bacteria can be pathogenic in pigs and suggest that porcine gastric disease may be mediated, in part, by colonization of the stomach by swine-origin H pylori-like bacteria.

Infection with Corynebacterium pseudotuberculosis in five alpacas

Among the population of an alpaca breeding farm, 5 alpacas (22 days to 14 months old) developed focal swellings in the subcutaneous tissues of the head or neck. Infection with Corynebacterium pseudotuberculosis was confirmed on the basis of results of microbial culture of abscess material and a serum hemolysis inhibition assay to detect C. pseudotuberculosis toxin. The dams of the affected alpacas were seronegative for C. pseudotuberculosis toxin. The affected alpacas underwent surgical excision of the abscesses and were isolated from herdmates for 90 days; treatment was successful, and no other alpacas in the herd became infected. Common risk factors for sources of infection in the affected alpacas included housing in a maternity barn and a pasture. Also, the infection potentially originated from new alpacas introduced into the herd during the preceding 3 months. Infection with C. pseudotuberculosis should be considered as a differential diagnosis for camelids with peripheral lymphadenopathy or abscesses in subcutaneous tissues.

Clostridial disease associated with neurologic signs: tetanus, botulism, and enterotoxemia

Clostridial infections are found worldwide in almost all species of animals and may involve a variety of body systems and present with a diversity of clinical signs. Most damage done through clostridial infections is due to the action of toxins released from the bacteria.Thus, disease caused by Clostridium spp should more correctly be called intoxication. Two prominent clostridial infections are associated with neurologic signs: Clostridium botulinum and C tetani. In both infections, the mechanism that is responsible for causing the problem is similar, despite the remarkable difference in clinical presentation. In addition, neurologic signs are described with C perfringens types C and D but are not the dominant feature of these diseases.

Activation of the immune system is the pivotal event in the production of wasting disease in pigs infected with porcine circovirus-2 (PCV-2)

Porcine circovirus (PCV)-2, a newly described single-stranded circular DNA virus pathogen of swine is the cause of postweaning multisystemic wasting syndrome (PMWS). In gnotobiotic piglets, PCV-2 infection alone produces asymptomatic infection without evidence of overt PMWS. Gnotobiotic piglets infected with PCV-2 were injected with keyhole limpet hemocyanin in incomplete Freund's adjuvant (KLH/ICFA), and the effects on virus production and development of PMWS were determined. In the first experiment, piglets were injected subcutaneously on the left hip and shoulder, and viral burden was assessed in regional lymph nodes draining the injection sites and in contralateral lymph nodes 13-14 days after infection. Immune activation increased the number of virus antigen-positive cells in draining lymph nodes and increased the amount of infectious virus recovered by 1-4 log10. In a second experiment, the effects of injections of KLH/ICFA with or without concurrent stimulation of peritoneal macrophages by intraperitoneal injections of thioglycollate broth on induction of PMWS was assessed. All immunized piglets developed moderate to severe PMWS, whereas none of the piglets infected with PCV-2 alone developed PMWS. In PMWS-affected piglets, extensive replication of PCV-2 was documented by both immunocytochemistry and quantitative viral titrations. Thus, immune activation is a key component of the pathogenesis of PCV-2-associated PMWS in swine.

Synovial fluid analysis in cattle: a review of 130 cases

OBJECTIVE

To compare synovial fluid characteristics of cattle with infectious and noninfectious arthritis.

STUDY DESIGN

Retrospective cohort study.

ANIMAL OR SAMPLE POPULATION

130 cattle.

METHODS

Synovial fluid was analyzed for total nucleated cell count (NCC), absolute number and percentages of polymorphonuclear (PMN) and mononuclear cells, total protein (TP) concentration, and specific gravity. Cattle were categorized as having infectious or noninfectious arthritis based on physical and lameness examinations, joint radiographs, and microbial culture results. Kruskal-Wallis 1-way analysis of variance was used to compare synovial fluid analysis data from different categories. Selection of cut-off values for the calculation of likelihood ratios, sensitivity, specificity, and positive and negative predictive values was based on examination of the distribution of the data using histograms.

RESULTS

Cattle with infectious arthritis had significantly higher numbers of total NNC, PMN cells, TP concentration, and specific gravity (P = .0001) and a significantly higher percentage of PMN cells compared with cattle with noninfectious arthritis (P = .0001). The percentage of mononuclear cells was significantly higher in cattle with noninfectious arthritis (P = .0001).

CONCLUSIONS

Synovial fluid analysis is useful for differentiation of infectious and noninfectious causes of joint disease in cattle.

CLINICAL RELEVANCE

Cattle with a synovial fluid total NCC > 25,000 cells/microL, a PMN cell count > 20,000 cells/microL or more than 80% PMN cells, and TP > 4.5 g/dL should be considered to have infectious arthritis.

Determination of serum insulin concentration during intravenous glucose tolerance testing of healthy bulls

OBJECTIVE

To determine the insulin response curve during IV glucose tolerance testing of mature Holstein bulls.

ANIMALS

8 Holstein bulls between 5 and 8 years old and weighing between 911.5 and 1035.5 kg.

PROCEDURE

A 50% glucose solution was rapidly administered IV so that each bull received a mean dose of 258 mg of glucose/kg of body weight. Serum glucose and insulin concentrations were determined before and 30, 60, 120, and 240 minutes after glucose infusion.

RESULTS

Serum glucose concentrations 30 and 60 minutes after infusion were significantly greater than baseline concentration. Concentrations returned to baseline values 120 minutes after infusion. Serum insulin concentration was significantly greater 30 minutes after glucose administration, compared with baseline and 240-minute concentrations.

CONCLUSIONS AND CLINICAL RELEVANCE

Intravenous glucose tolerance testing of mature Holstein bulls resulted in a characteristic insulin response curve. Baseline and peak insulin concentrations were higher in these bulls, compared with values reported for mature Norwegian Red cows.

Lymphosarcoma of the frontal sinus and nasal passage in a cow

A 5-year-old cow was evaluated because of a 2-week history of ataxia and other vague neurologic signs. Previous treatments included intravenous and orally administered calcium, but improvement was not seen. Bilateral mucoserous nasal discharge and a pair of firm, smooth masses caudodorsal to the eyes were found on the frontal bones on physical examination. The cow's condition deteriorated rapidly within 48 hours; head pressing and inability to rise were observed. The frontal sinuses were radiographically normal. Trephination of the frontal sinuses revealed a space-occupying mass that was interpreted on histologic examination to be lymphosarcoma. Other evidence of neoplasia was not discovered on gross necropsy or histologic examination. Primary lymphosarcoma has not been described at this location in cows. Clinically it resembles chronic frontal sinusitis, and trephination may be necessary to differentiate the 2 diseases.

Production of gastroesophageal erosions and ulcers (GEU) in gnotobiotic swine monoinfected with fermentative commensal bacteria and fed high-carbohydrate diet

Erosions and gastroesophageal ulcers (GEU) were produced in the pars esophagea of young gnotobiotic swine fed a carbohydrate-enriched liquid diet and monoinfected with two different fermentative commensal bacteria, Lactobacillus and Bacillus sp. In contrast, piglets, fed a similar diet and inoculated with Gastrospirillum sp. (Helicobacter heilmannii), a helicobacter species that colonizes the gastric mucosa, did not develop GEU. Experimental GEU likely develops secondary to epithelial damage mediated by microbial-origin acids whose production is potentiated by high dietary carbohydrate and parietal cell-origin hydrochloric acid.

Intussusception in cattle: 336 cases (1964-1993)

OBJECTIVE

To evaluate risk factors and to describe clinical and laboratory findings, surgical management, and postoperative outcome for cattle with intussusception.

DESIGN

Hospital-based, case-control epidemiologic study and retrospective case series.

SAMPLE POPULATION

Medical records of cattle admitted to 17 veterinary medical teaching hospitals in North America.

PROCEDURE

Epidemiologic analysis of demographic data and detailed analysis of medical records for selected cattle.

RESULTS

336 cattle with intussusception were identified, 281 had small intestinal, 7 had ileocolic, 12 had cecocolic, and 36 had colocolic intussusceptions. Sex and season were not significantly associated with cattle developing intussusception, whereas calves < 2 months old were at greater risk of developing small intestinal intussusception than older cattle. Analysis of medical records of 57 cattle with intussusception revealed that these cattle were mildly hyponatremic, hypochloremic, hypocalcemic, azotemic, and hyperglycemic. Right flank laparotomy with a cow in a standing position, followed by intestinal resection and end-to-end anastomosis was the most common means of surgical correction. Overall survival rate (20/57; 35%) and postoperative survival rate (20/46; 43%) for cattle with intussusception were much lower than previously reported.

CLINICAL IMPLICATIONS

Although rare in cattle, intussusception was most common in calves < 2 months old. Survival rate for cattle treated for intussusception was low (< 50%).

Survival of Mycobacterium paratuberculosis and preservation of immunoglobulin G in bovine colostrum under experimental conditions simulating pasteurization

OBJECTIVE

To determine whether Mycobacterium paratuberculosis could survive in colostrum after pasteurization. Additionally, this study investigated the effect pasteurization had on IgG concentration in colostrum.

ANIMALS

Colostrum samples were collected from cattle (beef and dairy) owned by the state of Ohio.

PROCEDURE

Colostrum was divided into aliquots and inoculated with variable concentrations of M paratuberculosis (ATCC No. 19698: 10(4), 10(3), and 10(2) colony-forming units/ml). Half the samples at each concentration were subjected to pasteurization temperatures (63 C) for 30 minutes and the remainder were kept at approximately 20 to 23 C. All samples were incubated (Herrold's egg yolk medium with and without mycobactin J) and observed for growth during the next 16 weeks. Additionally, the IgG concentration of colostrum was determined by radioimmunoassay before and after pasteurization. Samples that coagulated at pasteurization temperatures were mechanically resuspended before measurement of IgG concentration.

RESULTS

Growth of M paratuberculosis was retarded but not eliminated by pasteurization. Growth was observed in all unpasteurized samples incubated on Herrold's egg yolk medium with mycobactin J but in only 2 of 18 pasteurized samples similarly cultured. Growth from pasteurized samples appeared 5 to 9 weeks after growth was observed from nonpasteurized samples. Mean colostral IgG concentration was 44.4 g/L in nonpasteurized samples and 37.2 g/L in pasteurized samples, a decrease of 12.3%. High-quality colostrum (> 48 g of IgG/L) had a significantly greater loss of IgG concentration than did colostrum of lesser quality (P = 0.002).

CONCLUSIONS

Pasteurization lessened, but did not eliminate, growth of M paratuberculosis from experimentally inoculated colostrum samples. Pasteurization resulted in a significant decrease in colostral IgG concentration but not to an unmanageable level that would preclude the colostrum's use for passive transfer of immunity.

CLINICAL RELEVANCE

Colostrum is macrophage rich and may serve as a source of M paratuberculosis infection to calves. Pasteurization of colostrum may lessen the risk of infection, but will not totally eliminate M paratuberculosis.

Prevalence of lesions associated with subclinical laminitis in first-lactation cows from herds with high milk production

OBJECTIVE

To determine prevalence of lesions associated with subclinical laminitis in first-lactation Holstein cows during early lactation and pregnant Holstein heifers during late gestation in herds with high milk production.

DESIGN

Cross-sectional study.

ANIMALS

203 cattle in 13 herbs.

PROCEDURE

Cattle were placed in lateral recumbency to allow visual examination and photography of their hooves. Claws on a forelimb and hind limb were examined on all cattle. Observable categories of lesions considered to be associated with subclinical laminitis in our study included yellow waxy discoloration of the sole, hemorrhage of the sole, separation of the white line, and erosion of the heel.

RESULTS

Lesions in at least 1 of the categories were found in all herds. Lesions in all categories were found in 11 of 13 herds. Among claws, hemorrhage of the sole was observed most frequently in the lateral claw of the hoof of the hind limb. When days in milk was treated as a covariate, significant (P < 0.01) differences were detected in the prevalence of lesions between herds.

CLINICAL IMPLICATIONS

Because the prevalence of lesions differed significantly among herds, it is logical to believe that causative factors and corrective measures also may have differed among herds.

Isolation of Mycobacterium paratuberculosis from colostrum and milk of subclinically infected cows

Mycobacterial culture was performed on colostrum, milk, and feces from 126 clinically normal cows of a single herd with high prevalence of Mycobacterium paratuberculosis infection. Thirty-six (28.6%) cows were determined to be shedding the organism in the feces. Of the 36 fecal Culture positive cows, M paratuberculosis was isolated from the colostrum of 8 (22.2%) and from the milk of 3 (8.3%). Cows that were heavy fecal shedders were more likely to shed the organism in the colostrum than were light fecal shedders.

Occurrence of gastric ulcers in gnotobiotic piglets colonized by Helicobacter pylori

Archival gastric tissues from 10 of 39 gnotobiotic piglets colonized with Helicobacter pylori 26695 contained stromal leukocytic inflammation along with ulcers and erosions. In contrast, gastric tissues from 54 archival control piglets were devoid of both inflammation and ulcers. These data confirm the hypothesis that H. pylori infection alone is ulcerogenic.

Surgical treatment of pleuritis and pericarditis

Surgery of the bovine chest is rarely attempted; however, there are distinct indications and procedures available to treat both pericarditis, suppurative pleuritis and pleural effusions. Open lavage of the pericardial sac or pleural space has proven successful in carefully selected cases. The surgical procedures for pericardiotomy and thoracotomy are discussed.

Tracheal collapse

Tracheal collapse in calves usually is associated with dystocia at birth, especially breech presentations. Inspiratory dyspnea typically is seen within the first several months of life and may worsen progressively. Lateral cervical radiographs are useful in defining the affected segments as well as identifying previously fractured ribs. Surgical stenting of the trachea will improve the calf's condition, but because this procedure is done on young calves, the tracheal diameter of the affected segment is permanently limited by the size of the prosthesis.

Umbilical hernias, umbilical abscesses, and urachal fistulas. Surgical considerations

Swellings of the umbilical stalk, with or without herniation, are common findings in calves. Differentiation of involved structures is helpful in deciding the surgical approach and type of anesthesia required. This article deals with clinical signs, diagnostic procedures, and surgical techniques used to repair problems related to the umbilical stalk.

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.