Abomasal fistulas in dairy cows

Abomasal fistulas were corrected surgically in 9 adult Holstein cows. Six cows had a history of right paramedian abomasopexy (RPA), and 2 cows had had a percutaneous abomasopexy using the blind-stitch technique (BSA). Fistulas developed from 2 weeks to 12 months after the RPA or BSA. In 1 cow, history was not available beyond 2 years, and no surgery had been performed in that time. All fistulas were in the right paramedian area and were draining blood and/or ingesta from necrotic abomasal tissue (8 cows) or ruminal tissue (1 cow). Surgery was performed immediately in cows with consistent hemorrhage from the fistulated tissue (4 cows). Surgery was delayed to reduce rumen contents if bleeding was absent or considered negligible (4 cows) or to stabilize the patient (1 cow). General anesthesia was used in 7 cows, local anesthesia in 2 cows. Outcome following the fistula resection was successful in the 7 cows discharged from the clinic. The occurrence of abomasal fistulation is probably related to nonabsorbable sutures penetrating the abomasal lumen during the abomasopexy procedure resulting in infection of the incision or body wall.     

Comparison of abomasal luminal gas pressure and volume and perfusion of the abomasum in dairy cows with left displaced abomasum or abomasal volvulus

OBJECTIVE: To compare abomasal luminal gas pressure and volume and perfusion of the abomasum in dairy cows with a left displaced abomasum (LDA) or abomasal volvulus (AV). ANIMALS: 40 lactating dairy cows (25 with an LDA and 15 with an AV). PROCEDURE: Abomasal luminal gas pressure and volume and pulse oximetry values for the caudal portion of the dorsal ruminal sac and abomasal wall were measured during laparotomy. Abomasal perfusion was assessed on the basis of abomasal O2 saturation (pulse oximetry) before correction of the LDA or AV. Abomasal perfusion was also assessed after correction of the LDA or AV by measuring venous O2 saturation in the right gastroepiploic vein and calculating the abomasal oxygen-extraction ratio. RESULTS: Abomasal luminal gas pressure and volume were higher in cattle with an AV than in cattle with an LDA. Abomasal O2 saturation was lower and abomasal oxygen-extraction ratio higher in cattle with an AV, compared with values in cattle with an LDA. In cows with an AV, lactate concentration in the gastroepiploic vein was greater than that in a jugular vein, whereas no difference in lactate concentrations was detected in cows with an LDA. Abomasal luminal gas pressure was positively correlated (r, 0.51) with plasma lactate concentration in the gastroepiploic vein and negatively correlated (r, -0.32) with abomasal O2 saturation determined by use of pulse oximetry. CONCLUSIONS AND CLINICAL RELEVANCE: Abomasal perfusion decreases as luminal pressure increases in cattle with an AV or LDA.     

Ventral laparoscopic abomasopexy on adult cows

Displacement of the abomasum is frequently diagnosed by veterinarians in bovine practice and numerous surgical techniques have been developed to treat and prevent this condition. Complications secondary to those techniques are related to their degree of invasiveness and the development of postoperative wound infections. The objectives of this study were to describe a safe and reliable abomasopexy technique by laparoscopy and to assess postoperative adhesion formation. A ventral laparoscopic abomasopexy was performed on 10 adult dry cows. The abomasum was fixed with 4 simple interrupted sutures using USP 2 polydioxanone suture material. No major complications were encountered during the surgery. Abomasal adhesions were visually evaluated by laparoscopy 3 mo postoperatively. This technique proved to be simple and safe, and it provided adequate abomasum fixation in healthy dry cows. It could be used to surgically correct left displaced abomasum.     

Primary Repair of Abomasal Fistulae Resulting From Right Paramedian Abomasopexy in Eight Adult Dairy Cattle

Abomasal fistulae resulting from right paramedian abomasopexy in eight adult dairy cattle were treated by primary closure of the abdominal wall after surgical resection of the fistulae. The median elapsed time from the abomasopexy to recognition of fistula formation was 16 days (range, 10 to 90 days). All cows had normal electrolyte values, and five cows had mildly increased base excess values (range = 4.0 to 7.8 mEq/L). Surgery was performed with the cows in dorsal recumbency using general anesthesia. The fistulated tissue was resected and the abomasum and body wall were closed primarily. One or two layers of appositional sutures using #2 or #3 polyglactin 910 were used to close the body wall. Mean surgical time was 2.2 hours (range, 1.8 to 2.9 hours). Two cows were lost to follow-up. Five of the remaining six cows returned to production (range, 5 to 30 months). Primary closure of the abdominal wall should be considered in the surgical repair of abomasal fistulae in cows that do not have diffuse peritonitis.     

One-step laparoscopic abomasopexy for correction of left-sided displacement of the abomasum in dairy cows

Four adult dairy cows in which a diagnosis of left-displaced abomasum (LDA) had been made underwent a 1-step laparoscopic abomasopexy (LA). The technique was performed with each cow positioned in dorsal recumbency. Two laparoscopic portals were created in the right paramedian area to identify the abomasum and direct insertion of the steel trocar and cannula into the abomasal lumen. A stainless steel toggle pin (with 2 lengths of suture attached to its midpoint) was inserted via the cannula into the abomasal lumen while the excess suture material remained exterior to the abdomen. The abomasum was deflated, and the excess suture material was withdrawn up to a preset marker on the suture to position the abomasum adjacent to the body wall. The suture was then tied to secure the abomasum in place. By use of this 1-step LA technique, LDA was successfully corrected in all 4 cows. The procedure is minimally invasive and allows viewing of the abomasum for correct positioning and fixation; it can be accomplished with the speed associated with the blind roll-and-tack technique. The 1-step LA technique may reduce the incidence of complications associated with traditional laparotomy and the blind roll-and-tack technique and could be a useful alternative procedure for the treatment of LDA in dairy cows.     

Ultrasonographic assessment of change in abomasal position during the last three months of gestation and first three months of lactation in Holstein-Friesian cows

OBJECTIVE: To determine changes in abomasal position and dimensions during the last 3 months of gestation and first 3 months of lactation via transabdominal ultrasonography and determine whether surgical correction of left-displaced abomasum (LDA) by right flank omentopexy alters abomasal position within the abdomen in Holstein-Friesian cows. DESIGN: Observational study. ANIMALS: 20 heifers and 20 cows with no history of an LDA and 7 cows that had been treated for LDA via right flank omentopexy during an earlier lactation. Procedure-Ultrasonographic measurements were obtained 8 times during the last 3 months of gestation and first 3 months of lactation. Abomasal length, width, and volume were calculated from these measurements. RESULTS: The abomasum was always wider than it was long and located predominantly to the right of the midline. The presence of a right flank omentopexy had no effect on the measured parameters. Abomasal length decreased and width increased during the last 3 months of gestation, resulting in a more transverse orientation of the abomasum within the abdomen. These changes appeared to be in response to cranial expansion of the gravid uterus. The abomasum returned to a more caudal and right sagittal position within 14 days after parturition. CONCLUSIONS AND CLINICAL RELEVANCE: Abomasal dimensions, position, and volume change markedly during the last 3 months of gestation and first 3 months of lactation. Results permit detection of abnormal abomasal position in ill cows and indicate that the preferred location for abomasopexy is 20 cm caudal to the xiphoid process and 5 to 10 cm to the right of the ventral mid-line.     

Comparison of laparoscopic-guided abomasopexy versus omentopexy via right flank laparotomy for the treatment of left abomasal displacement in dairy cows

OBJECTIVE: To compare results obtained by use of laparoscopyassisted abomasopexy versus omentopexy via right flank laparotomy for the treatment of dairy cows with left displaced abomasum (LDA). ANIMALS: 120 dairy cows with an LDA. PROCEDURE: In a prospective clinical trial, cows were randomly allocated to the abomasopexy group (laparoscopy-assisted abomasopexy) or to the control group (omentopexy via right flank). Data were obtained during the first 5 days after surgery and 6 weeks and 6 months after surgery. RESULTS: 59 of 60 cows in the abomasopexy group and all 60 cows in the control group were treated successfully. Median duration was shorter for the laparoscopic procedure (27.5 minutes), compared with that for the control group (38 minutes). Five cows in the abomasopexy group had wound complications and 2 had LDA relapses, compared with 2 wound complications and no relapses in the control group. During the 5 days after surgery, the abomasopexy group had a significantly higher increase in rate of energy intake and milk yield and a more rapid return to reference range for serum glutamic dehydrogenase activity and total bilirubin concentration, compared with results for the control group. CONCLUSIONS AND CLINICAL RELEVANCE: Success rates were almost equal for both methods. Advantages of the laparoscopic abomasopexy procedure include practicality, low risk of complications, and rapid postoperative recovery. Contraindications are cardiopulmonary diseases. Other disadvantages include the cost of the instruments and inability to perform the procedure in cows with abomasal adhesions.     

Complications of blind-stitch abomasopexy: 20 cases (1980-1985)

Over a 5-year period, 20 adult Holstein cows were admitted to the New York State College of Veterinary Medicine because of complications following blind-stitch percutaneous abomasopexy for correction of left-displaced abomasum. Of the 20 cows, 16 were treated surgically, 2 were treated medically, and 2 were admitted to the pathology service for necropsy. Complications associated with the blind-stitch technique included peritonitis, cellulitis, abomasal displacement or evisceration, complete forestomach obstruction, and thrombophlebitis of the subcutaneous abdominal vein. Because of the various complications associated with blind-stitch percutaneous abomasopexy, we concluded that it is not an appropriate procedure for correction of left displaced abomasum in valuable cattle, but may be used as an alternative for salvage in less valuable cows.     

Right displacement of the abomasum and abomasal volvulus in dairy cows: 458 cases (1980-1987)

Clinical and surgical findings in 458 dairy cows with right displacement of the abomasum or abomasal volvulus (AV) were analyzed to determine the association between these variables and the outcome (productive, salvaged, or terminal) of the affected cow. Heart rate at initial examination was higher in the salvaged and terminal groups of cows (P less than 0.0001) than in the productive group. The plasma Na+ concentration was lower in the salvaged and terminal groups of cows (P less than 0.0001) than in the productive group. The plasma C1- concentration was lower in the salvaged group of cows than in cows with either productive or terminal outcomes (P less than 0.0001). Anion gap was significantly higher (P less than 0.0001) in the salvaged and terminal groups than in cows classified as productive. On the basis of surgical findings, cattle with right displacement of the abomasum were more likely to survive than cows with AV. Cows that required fluid decompression of the abomasum via abomasotomy were less likely to survive than those in which gaseous decompression was performed. Cows with evidence of vascular compromise of the abomasal wall were less likely to survive than those with normal abomasal serosa. Preoperative heart rate and anion gap had positive correlations with the presence of abomasal necrosis, whereas temperature, venous blood pH, plasma bicarbonate, and base excess concentrations had negative correlations. Cows in terminal stages of AV were likely to have a mixed primary acid-base disturbance, consisting of metabolic alkalosis with superimposed metabolic acidosis. These findings were highly correlated with abomasal necrosis.     

Prognostic value of plasma L-lactate concentration measured cow-side with a portable clinical analyzer in Holstein dairy cattle with abomasal disorders

BACKGROUND: L-Lactate has been used as a prognostic indicator for ill humans and animals. A portable analyzer that measures L-lactate could help veterinarians decide to proceed with correction of a displaced abomasum. HYPOTHESES: The likelihood of a dairy cow with a displaced abomasum remaining in the herd can be predicted by lactate concentration and other variables. ANIMALS: Thirty-four healthy early-lactation dairy cows, and 131 cows with abomasal displacements (DA) presented to Cornell University, Ithaca, NY. METHODS: Plasma L-lactate was measured using a commercial analyzer (i-STAT). A cow had a positive outcome (PO) if she remained in the herd 30 days after surgical correction of the displaced abomasum and a negative outcome (NO) if she was culled or died in that time. A multivariable model with physical examination and clinicopathologic variables for predicting NO for cows with right-sided abomasal displacements was constructed. RESULTS: The median plasma L-lactate was 0.54 mM/L (interquartile range, 0.42-0.74) in healthy lactating Holstein cows. In cows with right-sided displaced abomasa, median plasma L-lactate concentrations were higher in cows with NO (5.88 mM/L) versus PO (3.23 mM/L) (P = .002). In a multivariable model, which identified chloride, heart rate, and L-lactate as the best fitting variables for cows with right-sided displacements, the probability of NO increased as L-lactate increased. CONCLUSIONS AND CLINICAL IMPORTANCE: Plasma L-lactate concentration might be a useful predictor of productive outcomes in cows with right-sided abomasal disorders.     

A mechanism of excessive accumulation of abomasal gas in vagotomized cattle determined using fluoroscopy

To better understand the mechanism of excessive gas accumulation in the abomasum in bovine abomasal displacement, we performed gastric fluoroscopy in vagotomized cattle. Fifteen 6-month-old Holstein steers were divided into three groups: a non-vagotomized control group (Group C; n=5), a ventral thoraco-vagotomized group (Group V; n=5), and a dorsal and ventral thoraco-vagotomized group (Group DV; n=5). These groups were examined by fluoroscopy before and during a 5-week observation period after surgery. In Group C, no change was observed throughout the observation period. In Group DV, immediately after surgery, reticuloruminal motility was completely absent and ruminal distention was seen. Two weeks after surgery, abnormal reticulum motility and increased gas accumulation in the abomasal body were noted. Abomasal dilatation was also observed. In Group V, 1 week after surgery, gas inflow into the abomasum and relatively normal reticulum motility were observed along with a rapid increase in abomasal gas. Abomasal dilatation was also observed. In addition, left-displaced abomasum occurred in one of the steers in this group. From these results, we concluded that one of the mechanisms of excessive gas accumulation in the abomasum is reticulum-mediated gas inflow from the rumen combined with vagotomy-induced hypomotility.     

Left abomasal displacement and ulceration in an eight-week-old calf

Left displacement of the abomasum was diagnosed radiographically in an 8-week-old female Friesian calf. At surgery, a 4 cm ulcer was repaired and an abomasopexy performed during closure of the abdomen. Recovery from surgery was slow, and regurgitation of rumen contents occurred. Despite medical treatment, the calf died 4 days later. Left abomasal displacement is a well documented disease of dairy cattle (Robertson 1968; Coppock 1974; Martin et al 1978a; Poulsen 1976), but in young calves the condition is rare (Dirksen 1981). This report describes a case of left abomasal displacement with ulceration in an 8-week-old female Friesian calf.     

A comparison in 101 dairy cows of right paralumbar fossa omentopexy and right paramedian abomasopexy for treatment of left displacement of the abomasum

Right paramedian abomasopexy and right paralumbar fossa omentopexy appear to be the most widely used means of correcting left displacement of the abomasum in dairy cattle. We compared these two procedures in a prospective study of 101 cows with uncomplicated left displaced abomasum. The surgical treatment (right paramedian abomasopexy, n = 48; or right paralumbar fossa omentopexy, n = 53) was assigned randomly. Follow-up information was obtained, at regular intervals, from one week through six months following discharge from the hospital. Milk production, reproductive performance, surgical complications, and length of time retained in the herd after surgery were obtained for each animal. There was a trend in favor of the abomasopexy group in the one-month milk yield. There were no differences between procedures either in incisional complications, other problems noted at follow-up, or in the proportion dead/culled. Based on the milk yield at one month after surgery, we concluded that there may be a slight advantage to right paramedian abomasopexy in cows with uncomplicated left displaced abomasum.     

Abomasal impaction in Holstein-Friesian cows: 80 cases (1980-2003)

OBJECTIVE: To determine clinical examination findings, clinicopathologic abnormalities, and outcome of treatment in dairy cattle with abomasal impaction. DESIGN: Retrospective study. ANIMALS: 80 lactating Holstein-Friesian cows > or = 2 years old. PROCEDURE: Medical records of cattle with abomasal impaction admitted between 1980 and 2003 were retrieved, and data were extracted. RESULTS: All cows were reported to have decreased food intake; concurrent diseases were identified in 54 (68%). Seventeen cows did not have detectable ruminal motility, but physical examination findings were nonspecific and variable. In general, cattle had mild hypocalcemia, hyperbilirubinemia, and hyperglycemia, but serum potassium and chloride concentrations were typically within reference limits. Fifty-five (69%) cattle had impaction of the pyloric antrum alone, and 25 (31%) had impaction of the abomasal body and pyloric antrum. Right flank laparotomy and abomasal massage were performed in 73 cattle. After surgery, 54 (74%) cattle received 3 to 4 L of mineral oil, PO, daily for 1 to 5 days. Short-term (ie, discharged from the hospital) survival rate was significantly higher for cows with impaction of the pyloric antrum alone (42/45 [93%]) than for cows with impaction of the body and antrum (12/24 [50%]). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that physical examination findings and results of serum biochemical analyses do not facilitate the diagnosis of abomasal impaction in lactating Holstein cows and that exploratory right flank laparotomy is necessary to make the diagnosis. Abomasal impaction should be considered as a differential diagnosis for inappetence and poor milk production in lactating dairy cows.     

Insulin resistance and abomasal motility disorders in cows detected by use of abomasoduodenal electromyography after surgical correction of left displaced abomasum

OBJECTIVE: To determine the correlation between insulin concentrations and myoelectrical activity of the abomasum in cows with a left displaced abomasum (LDA). ANIMALS: 14 dairy cows with an LDA at the onset of lactation. PROCEDURE: During surgical correction of an LDA, 3 pairs of electrodes were placed in the smooth muscle of the gastrointestinal tract (abomasal body, pars pylorica, and duodenum) of each cow. Electromyographic recordings were obtained once per day for 7 days. Samples were collected and tested to determine concentrations of insulin, glucagon, cortisol, glucose, beta-hydroxybutyrate, and nonesterified fatty acids. RESULTS: All 14 cattle had high glucose and insulin concentrations at the time of admission, independent of ketosis. Concentrations of glucose and insulin decreased slowly after surgical treatment and were associated with a progressive increase in abomasoduodenal myoelectric activity. The 14 cows were allocated into 2 groups (suspected insulin-resistant cattle, n = 7; suspected non-insulin-resistant cattle, 7) on the basis of persistent hyperinsulinemia during the postoperative period. Seven days after surgery, the abomasoduodenal myoelectric patterns were still significantly lower for the insulin-resistant cows, compared with patterns for the non-insulin-resistant cows. CONCLUSIONS AND CLINICAL RELEVANCE: Insulin resistance appears to be common in cows with an LDA. Analysis of results of this study reveals that abomasal atony in cows with an LDA depends on persistence of high serum concentrations of insulin. Results of this study could provide an explanation for a pathogenetic factor of LDAs and the frequent relapses of cattle affected by this condition.     

Abomasal displacement and volvulus in beef cattle: 19 cases (1988-1998)

OBJECTIVE: To assess signalment, history, results of clinical and laboratory testing, and outcome for beef cattle with a left displaced abomasum (LDA), right displaced abomasum (RDA), or abomasal volvulus (AV). DESIGN: Retrospective study. ANIMALS: 19 beef cattle with an AV, LDA, or RDA. PROCEDURE: Signalment; history; results of physical examination, diagnostic testing, and surgical exploration; and condition of the animal at discharge were obtained from medical records. RESULTS: Fourteen cattle had an AV, 4 had an RDA, and 1 had an LDA. Duration of clinical signs ranged from 1 to 21 days. Eighteen cattle had an AV or RDA; 7 were Brahmans, 12 were males, and median age was 10 months. Abdominal distention was observed in 11 cattle, heart rate of > or = 100 beats/minute was detected in 14, and the abomasum was palpable per rectum in all cattle in which per rectal examination was performed. Leukocytosis, neutrophilia, hyperglycemia, azotemia, hypochloremia, and hypokalemia were common laboratory findings. At surgery, 3 cattle with an AV or RDA had a ruptured abomasum. Of the remaining 15 cattle, 12 survived. CONCLUSIONS: Clinical course in beef cattle with an AV or RDA was more protracted than that typically associated with these conditions in dairy cattle, but survival rate in beef cattle that did not have rupture of the abomasum was similar to that of dairy cattle. CLINICAL RELEVANCE: Abomasal displacement should be considered for beef cattle with abdominal distention. Prognostic indicators recommended for use in dairy cattle may not be useful for beef cattle.     

Effect of preoperative administration of erythromycin or flunixin meglumine on postoperative abomasal emptying rate in dairy cows undergoing surgical correction of left displacement of the abomasum

Objective: To determine whether preoperative administration of erythromycin or flunixin meglumine altered postoperative abomasal emptying rate, rumen contraction rate, or milk production in dairy cattle undergoing surgical correction of left displacement of the abomasum (LDA). DESIGN: Nonrandomized, controlled clinical trial. ANIMALS: 45 lactating Holstein-Friesian cows with LDA. PROCEDURES: Cows were alternately assigned to an erythromycin (10 mg/kg [4.5 mg/lb], IM), flunixin (2.2 mg/kg [1.0 mg/lb], IV), or control group (n = 15/group). Treatments were administered once 1 hour before surgical correction of LDA. D-Xylose solution (50%; 0.5 g/kg [0.23 g/lb]) was injected into the abomasal lumen during surgery, and venous blood samples were periodically obtained to determine time to maximum serum D-xylose concentration. RESULTS: Abomasal emptying rate was significantly faster in cows treated with erythromycin (mean +/- SD time to maximum serum D-xylose concentration, 149 +/- 48 minutes) than in control cows (277 +/- 95 minutes) but was not significantly different between cows treated with flunixin (230 +/- 49 minutes) and control cows. Cows treated with erythromycin had significantly greater milk production, relative to production before surgery, on postoperative days 1 and 2 than did control cows. Cows in the erythromycin and flunixin groups had a significantly higher rumen contraction rate on the first postoperative day than did control cows. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that preoperative administration of a single dose of erythromycin increased abomasal emptying rate, rumen contraction rate, and milk production in the immediate postoperative period in cows undergoing surgical correction of LDA.     

Serum Amyloid A and Haptoglobin Concentrations and Liver Fat Percentage in Lactating Dairy Cows with Abomasal Displacement

Background: There has been increased interest in measuring the serum concentration of acute phase reactants such as serum amyloid A [SAA] and haptoglobin [haptoglobin] in periparturient cattle in order to provide a method for detecting the presence of inflammation or bacterial infection.
Objectives: To determine whether [SAA] and [haptoglobin] are increased in cows with displaced abomasum as compared with healthy dairy cows.
Animals: Fifty-four adult dairy cows in early lactation that had left displaced abomasum (LDA, n = 34), right displaced abomasum or abomasal volvulus (RDA/AV, n = 11), or were healthy on physical examination (control, n = 9).
Materials and Methods: Inflammatory diseases or bacterial infections such as mastitis, metritis, or pneumonia were not clinically apparent in any animal. Jugular venous blood was obtained from all cows and analyzed. Liver samples were obtained by biopsy in cattle with abomasal displacement.
Results: [SAA] and [haptoglobin] concentrations were increased in cows with LDA or RDA/AV as compared with healthy controls. Cows with displaced abomasum had mild to moderate hepatic lipidosis, based on liver fat percentages of 9.3 ± 5.3% (mean ± SD, LDA) and 10.8 ± 7.7% (RDA/AV). [SAA] and [haptoglobin] were most strongly associated with liver fat percentage, r _s=+0.55 ( P < .0001) and r _s=+0.42 ( P = .0041), respectively.
Conclusions and Clinical Importance: An increase in [SAA] or [haptoglobin] in postparturient dairy cows with LDA or RDA/AV is not specific for inflammation or bacterial infection. An increase in [SAA] or [haptoglobin] may indicate the presence of hepatic lipidosis in cattle with abomasal displacement.     

Studies on the pH value of abomasal contents in dairy cows during the first 3 weeks after calving

The pH value of the abomasal contents in adult cattle is normally constant and has a value of 2. Abomasal contents with pH values of 5.5 and higher could give rise to bacterial fermentation with subsequent gas production. The accumulation of gas is thought to form a key event in the pathogenesis of abomasal displacement. The aim of the present study was to determine the pH values of abomasal contents of dairy cows in the first 3 weeks after calving. The pH of the abomasal contents was, over several days. higher than the pH value of the abomasal juice in mid-lactation cows. The highest pH values were measured on day 14 after calving, thereafter the pH declined. Possible explanations for the rise in the pH value of the abomasal contents are discussed.     

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.