Timpanismo ruminal crônico secundário à hipoplasia de pregas de omaso em dois bovinos / Chronic ruminal bloat secondary to omasal laminae hypoplasia in two cattle

Um novilho normando e outro charolês apresentando distensão abdominal, diarreia intermitente e timpanismo ruminal crônico, que iniciaram após desmame, foram enviados para necropsia. Observou-se ausência de pregas omasais associada à hipoplasia do órgão, assim como redução de tamanho das papilas ruminais e reticulares. Com base nas lesões e histórico, conclui-se que o timpanismo ruminal foi ocasionado pela falha no desenvolvimento do omaso...

Two emaciated juvenile steers, one Normande and one Charolaise breed with abdominal distension, intermittent diarrhea and chronic ruminal bloat that had begun at weaning were necropsied. Absence of the omasal laminae with omasal hypoplasia were found together with loss of ruminal papillae and reticular folds. Based on the lesions and history we concluded that the ruminal bloat was due to a development failure of the omasum...

The fatty acid profile of subcutaneous and abdominal fat in dairy cows with left displacement of the abomasum.

The objective of this study was to determine the fatty acid (FA) profile and assess desaturase indices of nonesterified fatty acids (NEFA) in the blood, as well as in the abdominal (ABD) and subcutaneous (SUBC) fat stores, in dairy cows with left displacement of the abomasum (LDA). Blood, ABD, and SUBC samples were taken from 50 Holstein cows offered for surgery to correct LDA. The FA profile of the 3 compartments was determined by gas chromatography after lipid extraction, methylation, and, in the case of blood plasma, separation of lipid classes. The most abundant FA in all 3 compartments were 16:0, 18:0, and 18:1 cis-9, with a total proportion of 82.5, 68.0, and 74.1g/100 g of FA in ABD, NEFA, and SUBC, respectively. A principal component analysis was performed on the entire FA profile as well as on the Δ(9)-desaturase indices (14:1 cis-9/14:0, 16:1 cis-9/16:0, 18:1 cis-9/18:0). The principal component analysis extracted 2 principal components (PC), representing 51.6% (PC1) and 21.1% (PC2) of the total variance in FA composition of the 3 compartments. The loading plot for the regression factors revealed a strong positive correlation between PC1 with the Δ(9)-desaturase indices and the proportions of 14:1 cis-9 and 16:1 cis-9, and revealed a negative correlation with the proportion of 18:0 and saturated FA. The correlation with PC2 was positive for the proportion of unsaturated FA, 18:2n-6, and 18:3n-3, and negative for the proportion of 14:0, 16:0, and saturated FA. The SUBC could be distinguished from the NEFA and ABD by a positive score for PC1, whereas differentiation among the latter 2 compartments could be made by a positive (NEFA) or negative (ABD) score for PC2. The Δ(9)-desaturase indices for C14 and C16 differed between all compartments but were numerically closer for NEFA and ABD versus NEFA and SUBC. The desaturase indices of the main FA (18:1 cis-9 and 18:0) did not differ between NEFA and ABD. These results support the existence of a different FA composition in ABD compared with SUBC. The greater similarity between the FA profiles of ABD and NEFA compared with SUBC and NEFA and the closer desaturase indices of ABD and NEFA support the hypothesis of a preferential mobilization of ABD fat in dairy cows with LDA.

Genetic parameters for producer-recorded health data in Canadian Holstein cattle.

Health traits are of paramount importance for economic dairy production. Improvement in liability to diseases has been made with better management practices, but genetic aspects of health traits have received less attention. Dairy producers in Canada have been recording eight health traits (mastitis (MAST), lameness (LAME), cystic ovarian disease (COD), left displaced abomasum (LDA), ketosis (KET), metritis (MET), milk fever (MF) and retained placenta (RP)) since April 2007. Genetic analyses of these traits were carried out in this study for the Holstein breed. Edits on herd distributions of recorded diseases were applied to the data to ensure a sufficient quality of recording. Traits were analysed either individually (MAST, LAME, COD) or were grouped according to biological similarities (LDA and KET, and MET, MF and RP) and analysed with multiple-trait models. Data included 46 104 cases of any of the above diseases. Incidence ranged from 2.3% for MF to 9.7% for MAST. MET and KET also had an incidence below 4.0%. Variance components were estimated using four different sire threshold models. The differences between models resulted from the inclusion of days at risk (DAR) and a cow effect, in addition to herd, parity and sire effects. Models were compared using mean squared error statistic. Mean squared error favoured, in general, the sire and cow within sire model with regression on DAR included. Heritabilities on the liability scale were between 0.02 (MET) and 0.21 (LDA). There was a moderate, positive genetic correlation between LDA and KET (0.58), and between MET and RP (0.79).

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.

Minimally invasive field abomasopexy techniques for correction and fixation of left displacement of the abomasum in dairy cows.

To reduce the potential drawbacks associated with laparotomy techniques for correction and fixation of left displaced abomasums (LDA), minimally invasive techniques have been developed. This chapter reviews the toggle pin suture (TPS) and the laparoscopic abomasopexy procedures used in the field for correction and fixation of the abomasum for correction of left-displacement of the abomasum in dairy cows. The importance of case selection cannot be overestimated. By combining laparoscopy with the principle of the TPS procedure, the lack of visual control associated with the TPS procedure is eliminated, while the advantage of the speed of completion and minimal invasiveness provided by both procedures are maintained. Successful LDA treatment includes not only early detection and treatment of the LDA, but also the prevention of secondary ketosis and aggressive treatment of concurrent disease.

Surgery of the abomasum.

Abomasal diseases are common in cattle. Many of these diseases can be managed surgically. This article briefly discusses the various classifications of abomasal diseases. It focuses on the surgical treatment of these diseases. Surgical principles of conventional surgery and minimally invasive techniques are discussed.

The use biochemical and hepatic parameters to predict treatment outcome of dairy cows suffering from displacement of the abomasum.

In this prospective study the impact of fatty liver and an impaired liver function on the treatment outcome of displacement of the abomasum (DA) was investigated. In a yearlong period, all cows suffering from DA submitted to the clinic were included in this study. All cows were clinically examined before surgery and a serum sample was taken to measure the following parameters: ASAT, bilirubin, urea. Liver biopsy was performed in all cows. Liver fat content was measured gravimetrically and concentrations of triglycerides were measured using a commercial test kit. Reposition of DA was done using the method by Dirksen. A total of 365 cows with DA entered the study, 326 (89.3%) suffered from LDA and 39 (10.7%) from RDA. RDA-cows had significantly (p = 0.002) more days in milk than LDA-cows. RDA-cows had significantly (p < 0.001) higher urea concentrations than LDA-cows. Bilirubin concentrations (p = 0.008) and liver fat content, triglyceride concentrations and the ratio of triglycerides to fat (TRI/FAT) (p < 0.001) were significantly higher in LDA-cows. The majority of LDA-cows showed at least a mild fatty liver. Comparing the cows with successful and failed treatment showed that ASAT-activity (p = 0.021), bilirubin concentration (p = 0.001), triglyceride concentration in liver and TRI/FAT (all p < 0.001) were significantly higher in the unsuccessfully treated cows. In RDA cows, significant differences between successfully and unsuccessfully treated cows were only seen in urea concentration (p = 0.004). ROC-analysis was performed to determine whether any parameter is suitable for a prediction of treatment outcome. In RDA-cows no threshold value was traceable for urea concentration. In LDA cows, TRI/FAT showed the best curve progression. The threshold value of 53.5 % had a sensitivity of 0.720 and a specificity of 0.700. LDA-cows exceeding this threshold had a 2.4 higher risk of an unsuccessful treatment. Due to the good overall treatment success (92.3 %) the positive predictive value for an unsuccessful or ineffective treatment was 0.368 only. The results of our study clearly show that impaired liver function plays an important role in the outcome of treatment of LDA but not RDA. In spite of this no laboratory parameter provides sufficient power to make a predictive statement of treatment outcome.

Evaluation of ornithine carbamoyl transferase and other serum and liver-derived analytes in diagnosis of fatty liver and postsurgical outcome of left-displaced abomasum in dairy cows.

OBJECTIVE: To evaluate postsurgical outcome in dairy cows with left-displaced abomasum (LDA) with regard to severity of fatty liver and assess the usefulness of preoperative determination of serum ornithine carbamoyl transferase (OCT) activity, bile acids concentration, and other variables for evaluating liver function during the postsurgical convalescence period. DESIGN: Prospective study. ANIMALS: 68 Holstein cows. PROCEDURES: Blood and liver biopsy specimens were obtained during standing LDA surgery. Liver tissue was examined histologically and classified by severity of fatty change. Serum activities of liver-derived enzymes and concentrations of total lipids, triglycerides, bile acids, glucose, beta-hydroxybutyric acid, bilirubin, and nonesterified fatty acids were determined. RESULTS: Most cows with LDA and cows with severe fatty liver were detected within the first month after calving. Postsurgical outcome was related to severity of fatty liver. All cows that died had severe fatty liver. Serum activities of OCT, aspartate aminotransferase, and glutamate dehydrogenase and serum total bilirubin concentration were sensitive indicators of fatty liver. Serum bile acids concentration was not an accurate indicator of fatty liver. CONCLUSIONS AND CLINICAL RELEVANCE: Postsurgical outcome of cows undergoing surgery to correct LDA was related to fatty liver severity. Assessment of serum activities of OCT, aspartate aminotransferase, and glutamate dehydrogenase and serum total bilirubin concentration is recommended for diagnosis of fatty liver in dairy cows with LDA, whereas determination of bile acids concentration is not. The strong correlation between OCT activity and degree of hepatocellular damage supports use of this enzyme for assessing severity of fatty liver and predicting postsurgical outcome in cows with LDA.

Comparison of the odds of isolation, genotypes, and in vivo production of major toxins by Clostridium perfringens obtained from the gastrointestinal tract of dairy cows with hemorrhagic bowel syndrome or left-displaced abomasum.

OBJECTIVE: To compare the frequency of isolation, genotypes, and in vivo production of major lethal toxins of Clostridium perfringens in adult dairy cows affected with hemorrhagic bowel syndrome (HBS) versus left-displaced abomasum (LDA). DESIGN: Case-control study. ANIMALS: 10 adult dairy cattle with HBS (cases) and 10 adult dairy cattle with LDA matched with cases by herd of origin (controls). PROCEDURE: Samples of gastrointestinal contents were obtained from multiple sites during surgery or necropsy examination. Each sample underwent testing for anaerobic bacteria by use of 3 culture methods. The genotype of isolates of C. perfringens was determined via multiplex polymerase chain reaction assay. Major lethal toxins were detected by use of an ELISA. Data were analyzed with multivariable logistic regression and chi2 analysis. RESULTS: C. perfringens type A and type A with the beta2 gene (A + beta2) were the only genotypes isolated. Isolation of C. perfringens type A and type A + beta2 was 6.56 and 3.3 times as likely, respectively, to occur in samples from cattle with HBS than in cattle with LDA. Alpha toxin was detected in 7 of 36 samples from cases and in 0 of 32 samples from controls. Beta2 toxin was detected in 9 of 36 samples from cases and 0 of 36 samples from controls. CONCLUSIONS AND CLINICAL RELEVANCE: C. perfringens type A and type A + beta2 can be isolated from the gastrointestinal tract with significantly greater odds in cattle with HBS than in herdmates with LDA. Alpha and beta2 toxins were detected in samples from cows with HBS but not from cows with LDA.

Survival of dairy cows after surgery to correct abomasal displacement: 1. Clinical and laboratory parameters and overall survival.

The objective of this study was to compare the clinical and laboratory consequences of left and right displacement of the abomasum (LDA and RDA), short- and long-term survival after surgery and the findings in cows, that could not be cured by omentopexy. Data from 564 cases of displaced abomasum (466 LDA, 98 RDA) were analysed retrospectively. Clinical and laboratory findings were compared between the two manifestations of DA. Survival was assessed after 10 days and after 15 months. Necropsy was carried out on cows that died or were killed. On arrival at the clinic, left displacement of the abomasum (LDA) cows had been recognized as diseased for longer. LDA occurred earlier in lactation, and more cows with right displacement of the abomasum (RDA) were pregnant. Overall clinical symptoms were more severe in RDA than in LDA cows. Heart rate was higher, body temperature was lower, inanition, abnormal faeces and ruminal stasis were more frequent in RDA cows. Leucocyte counts were higher, and potassium and chloride levels were lower in RDA cows. Acetonuria was more frequent in LDA cows. More LDA than RDA cows were released from the clinic as cured (82.0% versus 74.5%). However, survival after the early post-surgical period was similar for RDA and LDA cows. At necropsy, diseases of the gastrointestinal system were the predominant finding in RDA cows, while in LDA cows, diseases of the liver and other concurrent diseases were more important.

Survival of dairy cows after surgery to correct abomasal displacement: 2. Association of clinical and laboratory parameters with survival in cows with left abomasal displacement.

This study examines the association of pre-surgical clinical parameters in cows with left displacement of the abomasum (LDA) with the probability of cure. Data from 466 cases of LDA in which omentopexy was performed were analysed. Cows were classified in three categories according to the outcome of treatment. Cows in the first category were cured, i.e. sent back to the farm for further milk production. Cows in the second category were sent for slaughter because of an unfavourable prognosis concerning productivity. Cows in the third category either died or were salvaged because of poor prognosis concerning survival. Factors were examined for their possible influence on the outcome of treatment by comparing the values of successfully treated cows to those cows that either died or had to be sent for slaughter. Factors that were associated with a favourable prognosis were a short duration of disease, an undisturbed general condition, good appetite, normal faeces, a higher body weight, lower haematocrit, haemoglobin and erythrocyte counts, lower urea, AST and bilirubin, and higher sodium, potassium and chloride concentrations compared with cows with an unfavourable prognosis. Haemoconcentration was associated with higher AST, bilirubin and urea and with low sodium, potassium and chloride. Acetonuria was associated with increased AST and bilirubin and low urea. Low sodium and potassium concentrations were associated with an impaired general condition. It is concluded that a thorough clinical examination with special emphasis on general condition, liver function and dehydration status is of great importance in determining the prognosis of abdominal surgery in cows with LDA.

[The behavior of superoxide dismutase (SOD) in serum of cows with abomasal displacement (DA)]. / Verhalten der Superoxiddismutase (SOD) im Serum von Kühen mit Dislocatio abomasi (DA).

After surgical reposition of displaced organs (abomasum, uterus, intestines) restoration of blood flow and oxygen supply generates oxygen radicals and other reactive oxygen species. SOD indicates radical stress of the organism. Subject of the study was the question if SOD can be detected in blood serum samples of cows and if there are differences in SOD activity between healthy cows and cows with Dislocatio abomasi (DA). We also wanted to investigate the influence of breed "Schwarzbunte" with DA (16 left/5 rights). The samples were drawn before and 1, 3 and 24 post op. Ten healthy cows of the same breed were also examined (2 weeks and 4-6 weeks after calving). There are no significant differences between the SOD activity of healthy cows and cows with DA, but the SOD activity of cows with left DA is significant lower than the activity of cows with right DA. Post op. SOD activity decreases; 24 h after surgery cows with left but not with right DA show an increase of SOD activity similar to values before surgery. There is a close positive correlation between SOD activity and protein concentration as well as negative correlation to concentration of free fatty acids after surgery. The behaviour of SOD activity shows that the surgical replacement of the displaced abomasum can generate a depression of the antioxidative capacity of the organism.

Using activity and milk yield as predictors of fresh cow disorders.

The objective was to determine whether daily walking activity and milk yields could be used as predictors of metabolic and digestive disorders early in lactation. Data were collected from 1996 through 1999 from 1445 dairy cows in 3 Florida herds. Walking activity, milk yield, and other measures were collected from a computerized dairy management system. Mixed models analysis was used for data on cows before their first detected estrus, as identified by difference in activity. Healthy cows were defined as those without any metabolic or digestive disorder during the prebreeding stage, whereas a sick cow had an occurrence of those disorders at any time during the prebreeding stage. Metabolic disorders were ketosis, retained placenta, and milk fever. Digestive disorders included displaced abomasum, indigestion, reduced feed intake, traumatic gastritis, acidosis, and bloat. Data from cows with known cases of ketosis, left displaced abomasum, and digestive disorders were analyzed to determine changes in activity and milk yield before those specific disorders were clinically diagnosed. Although walking activity was generally lower among sick cows, cows with ketosis, left displaced abomasum, and digestive disorders had higher than average activity 8, 9, and 8 d, respectively, before each diagnosed disorder. Daily milk yields of sick cows were approximately 15 kg/d less than milk yields of healthy cows. Milk yields were lower by 6, 7, and 5 d, respectively, before diagnoses of ketosis, left displaced abomasum, and digestive disorders. Cows with ketosis, left displaced abomasum, and general digestive disorders could possibly be detected about 5 to 6 d earlier than clinical diagnoses based on changes in daily walking activity and milk yield.

Classification of abomasal displacement in cows according to histopathology of the liver and clinical chemistry.

Histopathological features of livers and blood chemical values in cows with abomasal displacement were investigated. Liver biopsy samples were collected during redressment operations in 92 cows with abomasal displacement, and the samples were stained with haematoxylin and eosin or periodic acid Schiff (PAS). Blood was collected for chemical tests. Livers were histopathologically divided into the following four types: normal histology cases (21%), fatty degeneration cases (36%), cloudy swelling cases (19%) and fatty degeneration cases with cloudy swelling (24%). The number of PAS-positive samples was significantly higher in the normal histology group and significantly lower in the severe fatty degeneration group and severe cloudy swelling group. Cows with fatty degeneration had significantly higher levels of serum 3-hydroxybutyric acid, non-esterified fatty acid and aspartate aminotransferase than did those with cloudy swelling or normal histology. The results indicate that the morbid conditions of cows with abomasal displacement can be classified into four types.

Left paramedian abomasopexy in cattle.

Aims of surgery of left displacement of the abomasum (LDA) are to return the abomasum to its original position and create a permanent attachment in the position to prevent recurrence. Left paramedian abomasopexy was performed on six Holstein cows with LDA because normal position of the fundus of the abomasum is located in the left of the midline and the displacement initially only involves the fundus of the abomasum. All cows were recovered without recurrence of LDA. It is considered that the left paramedian abomasopexy could be a major alternative as a surgical treatment of LDA.

[Laparoscopic reposition and fixation of the left displaced abomasum in cattle]. / Laparoskopische Reposition und Fixation des nach links verlagerten Labmagens beim Rind.

This article explains a minimally invasive technique for surgical correction of the left displaced abomasum in cattle. Endoscopic photographs show how the abomasum will be deflated, replaced and percutaneously fixed. Laparoscopy makes it possible to fix the fundus of the abomasum in all clinical conditions, independent of size, gas filling and fluid in abomasum and rumen. Especially cases with extremely dilated abomasum and cases with small quantity of gas within the abomasum are no problem in percutaneous abomasopexy. Fixation of the pyloric part of the abomasum or other abdominal structures are avoided. Adhesions of the abomasum to the rumen or the left body wall and other pathologic conditions can be seen.

[Percutaneous fixation--or "doubling" the left-sidedness-- and righting of the displaced abomasum in milk cows]. / Zur perkutanen Fixation--oder das "Dübeln"-des links--und rechtsseitigverlagerten Labmagens bei Milchkühen.

In the time from 1st of May 1991 up to the 30th April 1995 in total 101 percutaneus fixations of displaced amomasi were done according to the method of GRYMER and STERNER (1982). In 90 cases it was a displacement to the left side (plus one rezidiv) and eleven cases to the right side. This method of fixation was not difficult. The milkyields of these cows in the year before the illness was higher than the average of the herds. In the year of the percutaneous fixation the milk yield went down, ever it was higher (655 kg = 9.1%) than the average. That of the young cows in first lactation was a little bit lower than the average (3.2%) but in the following year it was a little bit higher (50 kg). In total 17 patients with left side and four cows with right side displacement died or had be slaughtered. First week after surgery eight cows had to be killed due to: hepatitis (5x), foreign body (1x), peritonitis (1x) after fixation, perforated wall of the abomasum (1x). The examination shows, that a great number of cows after percutaneous abomasopexie according to GRYMER and STERNER (1982) can be used for a longer time with economically satisfying results.

Serum apolipoprotein B-100 concentrations in healthy and diseased cattle.

The purpose of this study was to establish the normal range of serum apolipoprotein B-100 (APO B-100) concentration in clinically normal cattle, and to assess its abnormalities with clinical diseases. We measured the serum concentration of APO B-100 in cattle of varying ages, breeds and sex, maintained under normal field conditions. Blood samples were obtained from 735 apparently healthy cattle and 146 cows with various diseases. The concentration of serum APO B-100 in cattle was assayed by the single radial immunodiffusion method. The concentration of serum APO B-100 in healthy adult breeding bulls (mean +/- SD: Holstein; 101 +/- 46 microg/ml, Japanese Black; 106 +/- 46 microg/ml) was significantly (P<0.001) lower than that in cows (Holstein; 259 +/- 63, Japanese Black; 210 +/- 46 microg/ml), while that of APO B-100 in steers (Holstein; 290 +/- 86 microg/ml, Japanese Black; 302 +/- 90 microg/ml) was similar to the level in cows. The concentration of serum APO B-100 in cattle varied with sex and breed. APO B-100 concentration in cattle was decreased in association with metabolic disorders such as ketosis, displaced abomasum and fatty liver. From these results, it is assumed that the level of serum APO B-100 will be applied to diagnosis of metabolic diseases in cattle.

Changes in blood ionized calcium and some other blood parameters before and after replacement of a left-sided displaced abomasum in dairy cattle.

Concentrations in ionized calcium and some other blood parameters including total calcium, magnesium, inorganic phosphate, sodium, potassium, chloride, acid-base and hematological parameters of 15 German Holstein dairy cows were studied before and after surgical replacement of a left sided displaced abomasum. Mild hemoconcentration and hypochloremia were characteristic findings. These parameters tended to become normal within a few days after surgery. Hypocalcemia and low plasma potassium levels were not characteristic in this study, suggesting that hypocalcemia does not play an important role in the initiation of LDA. It can be supposed from this study that the severity of pathological blood findings depends more on the rate of malfunction of the abomasum than on the length of existence of LDA.

Duodeno-abomasal reflux in cows with abomasal displacement.

The aim of this study was to investigate abomaso-duodenal digesta transport during abomasal displacement and after surgical correction of the abomasum, using intra-abomasal bile acid concentration. In healthy cows, bile acids were found in the abomasum, indicative of duodeno-abomasal reflux being a physiological event. In cows with left abomasal displacement (LDA), right abomasal displacement (RDA) and abomasal volvolus (AV), abomasal bile acid concentration was significantly higher than in healthy control cows. This was found to be true during surgery, on the first day as well as on the third day after surgery. Abomasal bile acid concentration was significantly different between LDA, RDA and AV, with LDA, RDA and AV showing lowest, intermediate and highest values respectively. In those with LDA and RDA, abomasal bile acid concentration significantly increased from surgery to first day after surgery, and decreased from first to third day after surgery. In AV cows, however, bile acid concentration declined constantly from surgery to third day after surgery. These findings indicate pathological duodeno-abomasal reflux during abomasal displacement and after surgical correction of the abomasum. Reflux seems to differ between forms of displacement (LDA < RDA < AV) and during recovery. Pathological duodeno-abomasal reflux is discussed as a consequence of functional and/or mechanical impediments on abomaso-duodenal digesta transport during abomasal displacement and after surgical correction of the abomasum.