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.     

Changes in leukocyte populations of cows with milk fever or displaced abomasum after calving

Most of the metabolic diseases of dairy cows occur within the first 2 wk after calving, and cows with a metabolic disease are prone to infectious diseases. Although metabolic diseases are generally recognized as a risk factor for infectious diseases owing to the associated decrease in immune function, the difference in immune status between cows with milk fever (MF) or displaced abomasum (DA) during the lactation period has not been clarified. Therefore, the peripheral blood leukocyte populations in 38 multiparous Holstein cows from 1 herd were analyzed after calving. The cows were divided into 3 groups according to health: 21 cows that remained clinically healthy throughout the experimental period (control group), 9 cows that had MF on the day of calving, and 8 cows with an onset of DA within 4 wk after calving. The T- and B-cell numbers were lowest at week 0, and they increased gradually after calving. There was no significant difference between the 3 groups in the number of each subset of leukocytes on the day of calving, but the number of CD8⁺ T-cells was significantly lower in the MF and DA groups than in the control group at week 1. The numbers of CD4⁺, CD8⁺, and WC1⁺ T-cells tended to be lower in the DA group than in control group from weeks 4 to 12, a tendency not observed in the MF group. These data suggest that when cows have DA around the time of calving, their lymphocyte numbers remain lower until 12 wk after calving.     

Ventral laparoscopic abomasopexy in 18 cattle with displaced abomasum

OBJECTIVE: To evaluate the feasibility and outcome of a technique for laparoscopic abomasopexy in cattle with displaced abomasum (DA). STUDY DESIGN: Retrospective study. ANIMALS: Dairy cattle (n=18). METHODS: Retrieved data included signalment, clinical findings, treatments, and outcome. Laparoscopic abomasopexy was performed with the sedated cow in dorsal recumbency. The pexy site was determined after identification of the antrum and the greater curvature of the abomasum. Three or 4 absorbable sutures were passed through the body wall and abomasal wall for abomasal fixation. Wound complications, DA recurrence, food consumption, owner satisfaction, and long-term survival were assessed. RESULTS: Left DA was diagnosed in 17 cows and right DA in 1 cow. Abomasal decompression was performed in 12 cows and abomasopexy was achieved in all cows. Surgical wounds healed without complication, except in 4 cows that had mild periportal swelling. Postoperative return to normal appetite occurred quickly except for 2 cows with concurrent diseases. Owner satisfaction varied from good to excellent. DA did not recur. CONCLUSION: Ventral laparoscopic abomasopexy was successfully performed in 18 cows with DA. Abomasal decompression was necessary for adequate abomasal manipulation and identification of landmarks for pexy. An adequate return to food consumption and no recurrence of DA occurred (mean follow-up, 15.5 months). CLINICAL RELEVANCE: Ventral laparoscopic abomasopexy is technically feasible and an effective method for surgical treatment of DA.     

Decision-tree analysis of treatment alternatives for left displaced abomasum

This study evaluates treatment alternatives for left displaced abomasum (LDA) in dairy cattle. The technique of decision-tree analysis was used to evaluate 3 treatment possibilities. A computerized spreadsheet decision tree was used for the evaluation. Results of this investigation suggested that surgical treatment had the highest expected monetary value. Closed surgical techniques had expected monetary values close to the surgical techniques. Rolling the cow had the lowest expected monetary value, but the expected monetary value for rolling was higher than the expected monetary value for selling. If an LDA recurs after treatment, surgical and closed surgical treatments are preferred over rolling. From this study, we can conclude that surgical and closed surgical treatment alternatives are preferred if expected monetary values are considered. Rolling is preferred over selling the cow. However, if an LDA recurs, selling the cow is preferred over rolling.     

Prevalence of endotoxemia in healthy postparturient dairy cows and cows with abomasal volvulus or left displaced abomasum

Left displaced abomasum (LDA) and abomasal volvulus (AV) occur most commonly in postparturient dairy cows. Our main hypothesis was that endotoxemia occurred more frequently in the peripheral blood of cows with LDA or AV than in healthy cows because increased luminal pressure in AV or LDA, or the presence of a hemorrhagic strangulating obstruction in AV, may have injured the abomasal mucosa, thereby facilitating translocation of luminal endotoxin into the circulation. Therefore, our main objective was to compare the prevalence and magnitude of endotoxemia in healthy postparturient cows with the prevalence and magnitude of endotoxemia in cows with AV and LDA. We examined 60 adult dairy cows in early lactation that were diagnosed with AV (n = 15) or LDA (n = 15) or were healthy on physical examination (control group, n = 30). Jugular venous blood was obtained from cows in all 3 groups, and right gastroepiploic venous blood was obtained during surgical correction of AV and LDA immediately after repositioning of the abomasum. Platelet-rich plasma endotoxin concentrations were measured with a chromogenic limulus amoebocyte lysate assay. Endotoxin was detected in jugular vein plasma in 50% (15/30) of control cows; however, the prevalence of endotoxemia was significantly lower (P < .05) in cows with AV (7%, 1/15) or LDA (20%, 3/15). Endotoxin was detected simultaneously in right gastroepiploic and jugular vein plasma in only 1 cow with LDA and 0 cows with AV. Contrary to our hypothesis, we conclude that endotoxemia is infrequently present in postparturient dairy cows with AV or LDA.     

Origin of abomasum gas in the cows with displaced abomasum

The gas composition of the rumen and the abomasum were investigated in 71 cows including 25 cows with displaced abomasum. The ratio of methane (CH4) to CO2 in the abomasum gas was higher than that in the rumen. In the incubated mixtures of fresh rumen fluid, CH4 was detected at a high concentration, while a small amount of CO2 and CH4 was found in incubated mixtures of fresh abomasum fluids. Hence, it was suggested that the gas in the abomasum originated not from the abomasum itself but from the rumen. In cows fed with mixed roughages and concentrates, the rumen CO2:CH4 ratio was higher compared with cows fed with roughages alone. Marked changes in rumen gas composition were presumed to be associated with changes in abomasum gas composition. Consequently, it is possible that feeding a large quantity of concentrates may increase the flow rate of the ingesta through the forestomach, so that the return rate of gas separated from the ingesta in the abomasum to the forestomach may also increase. Therefore, the frequent accumulation of a large amount of gas with concomitant changes in the total volatile fatty acid (VFA) concentration in the abomasum caused abomasal atony and subsequently displaced abomasum.     

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.     

Peritoneal fluid analysis in dairy cows with left displaced abomasum and abomasal volvulus

Peritoneal fluid (PF) was evaluated in 40 cows with left displaced abomasum (LDA) and 15 cows with abomasal volvulus (AV). PF was obtained by abdominocentesis at the right ventral abdomen at admission. Simultaneously, a blood sample was taken from the jugular vein. Biochemical and cytological variables in blood and PF specific for ischaemia, inflammation and cell damage were compared. Total protein, albumin, glucose and cholesterol were normal in PF of cows with LDA and AV. Although L-lactate increased in both groups, cows with AV had significantly higher values (LDA: 1.47/0.69/2.68 mmol/l; AV: 6.45/4.55/12.89 mmol/l (median/1. quartile/3. quartile)). D-dimer (LDA: 0.50/0.22/0.88 mg/l; AV: 1.11/0.40/1.85 mg/l) and LDH (LDA: 663/437/943 U/l; AV: 1099/750/1439 U/l) were only increased in PF of cows with AV. The number of leucocytes was normal; however, significantly more peritoneal neutrophils appeared necrotic or apoptotic after AV. PF of cows with abomasal displacement showed distinctive features of ischaemia and inflammation. Characteristics of haemostatic dysfunction and cell damage were mainly evident in PF of cows with AV. The results suggest that anti-inflammatory therapy is indicated in each cow with abomasal displacement. Additionally, medical treatment should be directed to prevent complications of ischaemia and reperfusion in cows with AV.     

Bar suture (toggle pin) vs open surgical abomasopexy for treatment of left displaced abomasum in dairy cattle

Fifty-nine dairy cows with left displacement of the abomasum were randomly assigned to receive 1 of 2 treatments. Twenty-eight were treated by right paramedian abomasopexy via laparotomy, and 31 were treated by percutaneous fixation of the abomasum, using the bar suture or toggle pin technique. Comparisons of the 2 groups, at 4 follow-up examinations, yielded no significant differences in return to normal milk production, return to normal feed intake, mortality, culling rate, tissue reaction at the surgical site, or redisplacement up to 60 days into the subsequent lactation.     

Polymorphonuclear neutrophil leukocyte function in clinical bovine patients and in cows with or withoutStaphylococcus aureus mastitis

A fluorochrome microassay was used to investigate peripheral blood polymorphonuclear leukocyte (PMNL) function in cattle. Glass-adherent PMNL were reacted withStaphylococcus aureus princubated in 20% bovine serum for 30, 60 and 90 min. Coverslips were stained with acridine organge (AO) followed by crystal violet to quench extracellular bacterial fluorescence. PMNL function was evaluated by counting the number of dead (stained red with AO) and live (stained green with AO)S. aureus contained within 100 PMNL. A phagocytic index was calculated as the average number of bacteria contained within PMNL. The percentage killing ofS. aureus was calculated from the average proportion ofS. aureus within PMNL that were dead.Six clinically normal Holstein calves, 3–4 months of age, were sampled on 6 consecutive days. PMNL phagocytosis and killing did not vary significantly (p>0.05) among repeated samplings per calf. PMNL function increased with increasing time of incubation of PMNL withS. aureus. Means (± SD) for percentage killing were 46.7±13.1, 57.4±11.6, and 62.1±9.8% for 30, 60 and 90 min of reaction, respectively. Means (± SD) for the phagocytic index were 2.9±0.8, 3.6±1.0, and 4.2±1.1 bacteria/PMNL for 30, 60 and 90 min of reaction, respectively. PMNL function was determined in 30 normal cattle of various breeds, age and sex, and these values were pooled to provide normal values for PMNL function.When values for bovine clinical patients (n=25) with various diagnoses were compared with normal values (defined by the mean ± 2SD for the 30 normal cattle) for PMNL function, only one patient was observed to exhibit PMNL hypofunction. A cow with disseminated intravascular coagulation in association with peracute coliform mastitis exhibited decreased PMNL killing capacity. Abnormal PMNL function was uncommon in the hospital population studied.Peripheral blood PMNL function was evaluated in lactating Holstein cows with (n=15) or without (n=15) chronic subclinicalS. aureus mastitis. There was no significant (p>0.05) difference in PMNL function among these cows.     

Milk production and left displaced abomasum: cause and effect relationships

In a Danish dairy herd affected with a number of cases of left displaced abomasum the milk production during the lactation periods of affected cows was retrospectively compared to that in two groups of non-affected cows. Group A contained all cows calving at the same time as the cases, and group B had one cow for each of the cases of similar age and with similar preceding production level. The average 305-days milk production was 610 kg lower among the cases than among cows in group B, as a best estimate of the amount of milk lost for each case of left displaced abomasum. The difference between mean production in groups B and A was 183 kg, indicating a higher than average production potential among cases, since matching on preceding production level had been carried out between the cases and the cows in group B, but not in group A. It may therefore be concluded that high yielding cows are at excess risk of left displaced abomasum, which in turn leads to a considerable loss of milk among affected cows.     

Polymorphonuclear leukocyte function in HIV-1-infected chimpanzees

The chemiluminescent characteristics of enriched populations of neutrophils from control and HIV-infected chimpanzees were assessed. Neutrophils from HIV-infected chimpanzees were suppressed in their ability to generate a normal response to particulate and soluble stimuli when compared to normal and hepatitis non-A, non B-infected controls. Particulate (latex beads) stimulation of neutrophils resulted in an aberrant response when contrasted with controls. Normal control responses were characteristically biphasic while the response from hepatitis NANB HIV-infected chimpanzees was not biphasic. Neutrophils challenged with a soluble (phorbol ester) stimulant also demonstrated a suppressed response. These data suggest that HIV infection has an additive suppressive effect on neutrophil function in chimpanzees previously infected with hepatitis NANB. The suppression of chimpanzee neutrophil function following HIV infection is similar to that seen in other non-primate viral and retroviral infections.     

Pyloric obstruction after toggle-pin fixation of left displaced abomasum in a cow

One potential complication of blind abomasopexy techniques, including the toggle-pin technique, is the possibility of creating pyloric outflow obstruction. Cows that have had left displaced abomasum corrected by this method should be observed closely for the first 48 postsurgical hours for signs of deterioration. If pyloric obstruction is suspected and the securing sutures are cut before fibrous adhesions have formed, permanent damage may be minimized.     

Blood parameters in Swedish dairy herds with high or low incidence of displaced abomasum or ketosis

Sixty dairy herds were studied to investigate the association between long-term incidence of displaced abomasum and clinical ketosis and body condition score and blood profiles, including parameters estimating energy metabolism and hepatic lipidosis in the periparturient period and early lactation. Blood samples were taken around parturition and in early lactation from cows without apparent clinical symptoms of metabolic disorders. A difference in metabolism between high and low incidence herds was shown post-partum by a lower metabolic index (the revised Quantitative Insulin Sensitivity Check Index, RQUICKI), and tendencies for higher concentrations of glucose, insulin and non-esterified fatty acids in the high incidence herds. High incidence herds had more cows and produced on average 1400kg energy-corrected milk per cow per year more than the low incidence herds. No differences were found in parameters reflecting liver cell damage. In the first 3weeks post-partum the RQUICKI was a more sensitive marker of herds with a high incidence of displaced abomasum and clinical ketosis than any of the individual parameters, but further research is needed before practical applications of the RQUICKI can be foreseen.     

Factors influencing the survival of dairy cows after correction of left displaced abomasum

OBJECTIVE: To determine factors that influenced culling or death of cows with left displaced abomasum (LDA) subsequent to correction by a roll-and-toggle (R&T) procedure or via laparotomy. DESIGN: Cohort study. ANIMALS: 810 Holstein dairy cows with LDA. PROCEDURES: Data regarding method of repair and risk factors for survival after correction of LDA were collected during a 1-year period. Outcomes were compared at days 14 and 60 after LDA correction for 3 groups of cattle (veterinarians performed R&T [V-R&T], herd personnel performed R&T [H-R&T], and veterinarians performed surgical repair via laparotomy [V-Surg]). RESULTS: Survival rates 14 days after LDA correction for the V-R&T, H-R&T, and V-Surg groups were 87% (286/329), 81% (327/403), and 85% (66/78), respectively. At 60 days after LDA correction, survival rates for the V-R&T, H-R&T, and V-Surg groups were 79% (260/329), 71% (286/403), and 73% (57/78), respectively. Multivariable analysis indicated that factors positively associated with failure to remain in the herd at 60 days after LDA correction included current mastitis status, history of a previous LDA, high preoperative risk, and correction of LDA by herd personnel rather than by a veterinarian. CONCLUSIONS AND CLINICAL RELEVANCE: Correction of LDA by veterinarians via an R&T procedure yielded results that were generally comparable to those for correction by veterinarians via laparotomy. Although survival rates at days 14 and 60 after surgery differed significantly between the V-R&T and H-R&T groups, herd personnel in this study used the R&T procedure to correct LDA and achieved survival rates within the range for those of practicing veterinarians.     

Glucose tolerance test during abomaso-duodenal electromyography in three cows operated for left displaced abomasum

The objective of the study was to analyze glucose metabolism and abomasal myoelectrical activity during an intravenous glucose tolerance test in cows operated for LDA. Three dairy cows, at the onset of lactation, suffering from left displaced abomasum were selected from the animals presented at the clinic. During surgical therapy, one pair of electrodes was placed in the smooth muscle of the abomasal body, the pars pylorica and the duodenum respectively. The animals were subjected to electromyography on five occasions during hospital admittance (Days 1, 2, 3, 5 and 7 post-operative); their insulin, glucagon, glucose, beta-hydroxybutyrate and NEFA levels were then measured. Two days after surgery, the animals were subjected to an intravenous glucose load (300 g glucose in 30 min) during abomaso-duodenal electromyography. The findings indicate that the three animals had glucose metabolism disorders during hospitalization. The abomaso-duodenal myoelectric activity of Cows 1 and 3 was lower than in Cow 2. During the glucose load, the analysis of hormones and metabolites showed that there were different degrees of reactivity and that myoelectric activity differed in the 3 cows. The results of the study suggest that despite the surgical reposition of the abomasum, disorders of abomasal motility persist in different degrees in cows operated for LDA and could be influenced by glucose administrations.     

Effects of management, feeding, and treatment on clinical and biochemical variables in cattle with displaced abomasum

OBJECTIVE: To determine effects of management, feeding, and treatment on clinical and biochemical variables in cows with displaced abomasum (DA). ANIMALS: 374 cows that received 470 treatments for DA. PROCEDURE: Blood and milk samples were obtained from 139 affected cows for analysis; for all cows, clinical data, management, feeding, and treatments were evaluated. RESULTS: Multiparous cows were more predisposed to DA than primiparous cows were, and Swedish Friesians were more predisposed than Swedish Red and Whites were. Eighty percent of cows had left-sided DA, and 20% had right-sided DA. In > 50% of affected cows, clinical signs appeared just before calving to 2 weeks after calving. Incidence of twin calves and periparturient diseases was significantly higher in affected cows than in the overall Swedish cow population. Content of neutral detergent fiber in the silage was low in herds with DA. Feeding a total mixed ration was a risk factor for DA. Treatment by surgical methods gave a significantly higher recovery rate than nonsurgical methods. CONCLUSIONS AND CLINICAL RELEVANCE: Displaced abomasum is a periparturient nutritional disease. Feeding roughage with low neutral detergent content is a more important causative factor than the amount of concentrates fed at the time of calving. The basic principle for prevention of DA is to maintain good ruminal filling before and at calving. The amount of high-quality roughage fed before and at calving should be kept to a minimum. By changing routines for periparturient feeding, it should be possible to reduce the incidence of DA.