Prognostic value of anion gap calculation in cattle with abomasal volvulus: 58 cases (1980-1985)

Values for anion gap, serum chloride, and base excess were tabulated for 58 dairy cows with abomasal volvulus. Test values for survivors (n = 40) and nonsurvivors (n = 18) were compared. Surviving cattle were released for production or salvage. Nonsurviving cows died or were euthanatized. Accuracy of preoperative anion gap, serum chloride, and base excess values in predicting outcome was evaluated by calculating the sensitivity, specificity, predictive value, and negative predictive value of these at assigned cutoff values. Anion gaps greater than or equal to 30 mEq/L were indicative of a poor prognosis. At this value, the sensitivity (0.889), specificity (0.925), predictive value (0.842), negative predictive value (0.949), and efficiency (0.914) were higher than when serum chloride concentration less than or equal to 84 mEq/L or base excess value less than or equal to 0 were used to denote poor prognosis. We concluded that preoperative anion gap calculation could reliably predict the outcome of cows with abomasal volvulus and was more accurate than either serum chloride concentration or base excess value.     

Phosphorus homeostasis in dairy cows with abomasal displacement or abomasal volvulus

Abnormal phosphorus homeostasis occurs in dairy cows with an abomasal displacement or volvulus. The goal of this study was to identify potential mechanisms for hypophosphatemia and hyperphosphatemia in cows with a left displaced abomasum (LDA), right displaced abomasum (RDA), or abomasal volvulus (AV). Accordingly, the results of preoperative clinicopathologic analyses for 1,368 dairy cows with an LDA (n = 1,189), RDA, or AV (n = 179) (data set 1) and for 44 cows with an AV (data set 2) were retrieved. Laboratory values were compared by Student's t-tests, and correlation and regression analyses were performed. Thirty-four percent of the animals from data set 1 (463/1,368) were hypophosphatemic (serum phosphorus concentration ([Pi]) < 1.4 mmol/L), and 9% (122/1,368) were hyperphosphatemic ([Pi] >2.3 mmol/L). Serum [Pi] was significantly lower (P < .05) in cows with an LDA (1.60 +/- 0.53 mmol/L; mean +/- SD) than in cows with an RDA or AV (1.85 +/- 0.68 mmol/L). For cows with an LDA, [Pi] was correlated with serum urea nitrogen concentration ([SUN]) (r = 0.34) and serum concentration of magnesium ([Mg]) (r = 0.20). For cows with an RDA or AV, linear correlations existed between [Pi] and [SUN] (r = 0.45), [Mg] (r = 0.43), and serum chloride concentration ([Cl]) (r = -0.27). Stepwise logistic regression analysis indicated that low [SUN] and the diagnosis of an LDA had the strongest associations with hypophosphatemia. In cows with hyperphosphatemia, [Pi] was most strongly associated with azotemia. In cows with an AV, the strongest correlations with [Pi] were found for [SUN] and serum creatinine. We conclude that hypophosphatemia in cows with an LDA is primarily due to decreased feed intake. In contrast, hyperphosphatemia in cattle with an RDA or AV appears to result from dehydration and decreased renal blood flow.     

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.     

Retrospective study on the outcomes and risk factors of right paramedian abomasopexy for right abomasal disorders in 47 dairy cows

Very few epidemiologic studies have verified the utility of the right paramedian abomasopexy (RPA) technique in cows with right abomasal disorders. This study aimed to investigate the outcomes and risk factors for non-survival in the herd within 30 days of surgery in cows with right abomasal disorders who underwent the RPA technique. Forty-seven Holstein cows with right abomasal disorders (25 with right abomasal displacement [RDA] and 22 with right abomasal volvulus [RAV]) were included. Twenty-two cows with RDA (22/25, 88.0%) and 10 cows with RAV (10/22, 45.5%) survived at 30 days post-surgery. Multivariate logistic regression analysis indicated that hyponatremia, hypokalemia, and the presence of abomasal volvulus were the major risk factors associated with non-survival.     

Evaluation of abomasal outflow diversion as an experimental model of hypochloremic, hypokalemic metabolic alkalosis in lactating cows.

Four adult, lactating dairy cows were subjected to diversion (loss) of gastric contents through a T-shaped cannula placed in the cranial part of the duodenum just distal to the pylorus. Diversion was continued for 10 to 12 hours, at which point the cows were very weak and depressed. The volume of effluent during this period ranged from 37.3 to 46.8 L, with the largest volume being produced during the first four hours. All cows became dehydrated, with mean packed cell volume and total plasma protein concentration increasing 30% and 19.6%, respectively, but with only a slight increase in plasma creatinine concentration. Plasma Cl- concentrations decreased from a mean of 97.3 mEq/L at the beginning of diversion to a mean of 87.2 mEq/L at eight hours. This was followed by a plateau or slight increase in concentrations over the final hours of diversion. Plasma K+ concentration followed a similar pattern, decreasing from a mean of 3.9 mEq/L to a mean of 2.94 mEq/L at six hours, followed by increasing values until termination of diversion. No changes in plasma Na+ concentration were noted, except for a mild decrease in one cow. Plasma calcium concentrations decreased significantly, reaching 6.6 +/- 0.6 mEq/L at the end of diversion. Venous pH, plasma HCO3- concentration, and plasma base excess concentration increased during the first four to eight hours of diversion, followed by a gradual decline. Although a mild hypochloremic metabolic alkalosis resulted from diversion of abomasal outflow in all cows, substantiated by a mild increase in plasma strong ion difference, the changes observed were not as great as expected.(ABSTRACT TRUNCATED AT 250 WORDS)     

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.     

Prognostic indicators in cattle with right-sided displacement of the abomasum and abomasal volvulus]

The records of 106 cases of right-sided displacement of the abomasum (RDA) and abomasal volvulus (AV) were reviewed. Pre- and postoperative heart rate (> or = 90 BPM), serum BUN (> or = 10 mmol/L), potassium (< or = 3.3 mmol/L) and chloride (< or = 85 mmol/L) were the best indicators for a non-productive outcome. High gamma-GT activity can be used as a preoperative indicator to differentiate AV from RDA. The overall rate of return to a productive life was 74% (81.2% of RDA cases and 67.3% of AV cases).     

Ultrasonographic examination of the omasum, liver, and small and large intestines in cows with right displacement of the abomasum and abomasal volvulus

OBJECTIVE: To describe ultrasonographic appearance of the liver, small and large intestines, and omasum in cows with right displacement of the abomasum (RDA) and with abomasal volvulus (AV) and to determine whether RDA and AV can be differentiated on the basis of ultrasonographic findings. ANIMALS: 17 cows with RDA, 9 cows with AV, and 10 healthy control cows. PROCEDURES: A linear transducer was used to examine the abomasum, liver, omasum, and small and large intestines from the right side. Results-The liver was imaged less frequently in cows with RDA or AV, compared with control cows. In 9 cows with RDA or AV, the liver could not be imaged. The small intestine was imaged less frequently in cows with RDA or AV than in control cows; in cows with AV, the small intestine could not be imaged in the 8th, 9th, or 10th intercostal space. The large intestine was imaged less frequently in the 11th and 12th intercostal spaces and the cranial region of the flank in cows with RDA or AV. The omasum was also imaged less frequently in the 8th and 9th intercostal spaces in cows with RDA or AV. Cows with RDA or AV could not be differentiated on the basis of ultrasonographic findings. CONCLUSIONS AND CLINICAL RELEVANCE: Compared with control cows, cows with RDA and AV had changes in positioning and therefore extent of ultrasonographic imaging of the liver, omasum, and small and large intestines; however, these findings were not useful in differentiating between cows with RDA and AV.     

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.     

Motility of the rumen and abomasum during hypocalcaemia.

The relationship between plasma calcium level and rumen motility in cows and sheep and abomasal motility in cows was investigated by inducing hypocalcaemia in seven cows and five sheep by the infusion of Na2 EDTA over a period of approximately two hours. Rates and amplitudes of rumen and abomasal contractions were markedly reduced by the reduction of plasma calcium level to approximately 50% of normal. There were significant positive linear relationships (P less than 0.05) between rate and amplitude of rumen contractions in both sheep and cows over a plasma calcium range of 1-3 mmol/L. There was also a significant linear relationship (P less than 0.05) between plasma calcium and abomasal rate of contraction over the same range in cows, but the relationship with amplitude of abomasal contraction was not quite significant (P less than 0.1 greater than 0.05).     

Effect of Preoperative Erythromycin or Dexamethasone/Vitamin C on Postoperative Abomasal Emptying Rate in Dairy Cows Undergoing Surgical Correction of Abomasal Volvulus

Objective— To determine the effects of preoperative erythromycin or combined dexamethasone/vitamin C treatment on postoperative abomasal emptying rate in cows undergoing surgical correction of abomasal volvulus (AV).
Study Design— Prospective, controlled, clinical study using a convenience sample.
Animals— Lactating Holstein–Friesian cows (n=45) with AV were alternately assigned to 3 groups (n=15): group C: untreated (control); group E: erythromycin (10 mg/kg intramuscularly [IM]); group D: dexamethasone (0.02 mg/kg intravenously [IV]) and vitamin C (10 mg/kg IV).
Methods— Drugs were administered 1 hour before surgical correction of AV. d -xylose solution (50%, 0.5 g/kg body weight) was injected into the abomasal lumen during surgery. Jugular venous blood samples for determination of serum d -xylose concentration were periodically obtained. Time to maximal serum d -xylose concentration (T_max-model) was pharmacokinetically determined.
Results— Abomasal emptying rate was significantly ( P <0.05) faster in group E (T_max-model=182±69 min; mean±SD) than in group C cows (T_max-model=237±64 min). Abomasal emptying rate was similar in group D (T_max-model=196±47 min) and group C. Both treatments improved postoperative milk yield within 1 day after surgery.
Conclusion— Preoperative injection of erythromycin (10 mg/kg IM) is an effective method for ameliorating postoperative abomasal hypomotility in cows with AV.
Clinical Relevance— Parenteral erythromycin can be recommended for preoperative treatment of cows with AV.     

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)     

Use of a multiple logistic regression model to determine prognosis of dairy cows with right displacement of the abomasum or abomasal volvulus

Data at admission and at surgery were collected on 458 cows with right displacement of the abomasum or abomasal volvulus, to derive multiple logistic regression models for predicting postsurgical outcome (productive, salvaged, or terminal). The derived models contained few and easily obtained variables. The weight associated with each variable was determined objectively. Three admission variables (heart rate, base excess, and plasma chloride concentration), and 5 surgical variables (heart rate, base excess, diagnosis, method of decompression used, and appearance of abomasal serosa) were used in the final models. Predicted outcomes that used the admission and surgical models were closely related with actual outcomes. Total correct classification for satisfactory (productive) versus unsatisfactory outcome (salvaged and terminal) was 78.2% for the admission model and 82.7% for the surgical model. Combining data on cows with productive and salvaged outcomes as satisfactory outcome, and terminal as unsatisfactory outcome, total correct classification was 90.7% for the admission model and 93.2% for the surgical model. Using predicted probabilities, the market value of productive and salvaged cows, and the medical and surgical costs, one can calculate the expected economic value of each outcome. Treatment can be justified if the sum of the expected value of productive and salvaged outcome exceeds the sum of the medical and surgical costs and the expected salvaged value of the cow that was not treated surgically.     

Use of the D-xylose absorption test to measure abomasal emptying rate in healthy lactating Holstein-Friesian cows and in cows with left displaced abomasum or abomasal volvulus

We determined the abomasal emptying rates of Holstein-Friesian cows at different stages of lactation, with left displaced abomasum (LDA), or immediately after surgical correction of LDA or abomasal volvulus (AV). D-xylose (0.5 g/kg body weight [BW], 50% solution) was injected into the abomasum in healthy cows (group 1, 4-7 days in milk [DIM], n = 7; group 2, 90-120 DIM, n = 7; group 3, > 300 DIM, n = 7) and in cows with LDA (n = 10; group 4). D-xylose was injected into the abomasum during right flank laparotomy in cows with LDA (n = 22; group 5) and cows with AV (n = 15; group 6). The time to maximal serum D-xylose concentration was used as an index of emptying rate. The abomasal emptying rates for cows in groups 1, 2, and 3 were similar, whereas emptying was slower in cows with LDA and in cows after surgical correction of LDA or AV. The abomasal emptying rate of cows with LDA was slowed to a greater extent immediately after surgery, when compared to the rate obtained before surgery. There was no difference in abomasal emptying rate immediately after surgical correction between cows with LDA or AV. The results indicate that the increased incidence of LDA in the first month of lactation is not associated with an intrinsic decrease in abomasal emptying rate in healthy cows. Our findings also demonstrate that surgical correction further slows the emptying rate in cows with LDA.     

The effect of the plasma glucose level on the abomasal function in dairy cows

We have studied the effect of plasma glucose level on the abomasal outflow rate of fluid using a hyperinsulinemic glucose clamp technique in dairy cows. Four nonpregnant, nonlactating cows were subjected to one of the following treatments: hyperinsulinemic normoglycemic clamp; hyperinsulinemic hypoglycemic clamp; hyperinsulinemic hyperglycemic clamp; or, as a control, an intravenous infusion of .9% sodium chloride in a Latin square design. The cows were previously fitted with a permanent fistula in the abomasum and the outflow rate of abomasal fluid was determined using Co-EDTA as a marker assuming that the outflow followed first-order kinetics. The abomasal pH was also registered. Insulin was infused continuously through a jugular catheter at a rate of 4.8 mU. kg(-1)min(-1) for 2.5 h in the three clamp treatments. A glucose solution was infused through the catheter at a variable rate to achieve a circulating concentration, near the preinfusion glucose level (approximately 4.1 mmol/L), 2 mmol/L below the preinfusion level, and 2 mmol/L above the preinfusion level for the three hyperinsulinemic treatments, respectively. There was a significant effect of treatment on the rate of abomasal outflow (P < .001). The rate of abomasal outflow was highest for the control treatment (7.8%/min). The slowest outflow was observed in the hyperglycemic cows (3.40%/min). The hypoglycemic and normoglycemic cows showed intermediate rates (6.0%/min and 5.2%/min, respectively). The rate of outflow for the hyperglycemic cows was significantly lower than for all the other treatments (P < .01). Abomasal pH was affected by treatment (P < .05). The highest pH was observed in the hyperglycemic cows (pH 2.3). The values for the other three treatments ranged from pH 1.9 to 2.0. These results show that hyperglycemia reduced the rate of outflow and increased the pH of abomasal fluid in dairy cows. An elevated plasma glucose level thus can be considered as a potential risk factor in the pathogenesis of left-displaced abomasum.     

Ultrasonographic findings in cows with right displacement of the abomasum and abomasal volvulus

Seventeen cows with right displacement of the abomasum (rda) without abomasal volvulus, nine cows with abomasal volvulus and 10 clinically healthy cows were examined ultrasonographically. A 5.0 MHz transducer was used to scan the eighth to 12th intercostal spaces and the cranial and caudal aspects of the flank on the right side. The position, size and dorsal and ventral margins of the abomasum were determined at each imaging position. In both groups of diseased cows, the ventral abomasum contained fluid ingesta, which appeared hypoechogenic with diffuse echogenic stippling. The abomasal folds could be seen clearly as echogenic sickle-shaped structures within the ingesta. The dorsal abomasal gas cap varied in size and was characterised by reverberation artefacts, which appeared as echogenic lines running parallel to the body surface. Compared with the healthy cows, the abomasum was larger and located significantly closer to the midline of the dorsum in both groups of cows. Compared with the cows with rda, the abomasum in the cows with abomasal volvulus was significantly smaller in the eighth intercostal space and significantly larger in the 11th intercostal space. It was not possible to differentiate between rda and abomasal volvulus on the basis of the ultrasonographic findings.     

Cross-sectional study of the association of abomasal displacement or volvulus with serum electrolyte and mineral concentrations in dairy cows

The objective of this study was to evaluate serum mineral and electrolyte concentrations at the time of on-farm diagnosis of left displaced abomasum, right displaced abomasum, or abomasal volvulus in dairy cows. Data were collected from 104 affected cows and 96 control cows matched with cases, based on herd, parity, and stage of lactation. Cows with abomasal displacement or volvulus had significantly lower calcium, phosphorous, magnesium, potassium, and chloride concentrations and increased anion gap at the time of diagnosis compared with control cows from the same herds. The percentages of cases and controls with total serum calcium concentrations below the lower limit of the laboratory reference range (2.08 mmol/L [8.3 mg/dL]) were 70% and 23%, respectively. Based on the large percentage of cases with hypocalcemia, administering calcium salts at the time of treatment of field cases of abomasal displacement or volvulus may be beneficial.     

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.     

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.     

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.