Ultrasonographic findings in cows with left displacement of the abomasum

Left and right displaced abomasum and abomasal volvulus: comparison of clinical, laboratory and ultrasonographic findings in 1982 dairy cows

BACKGROUND

Although left and right displacement of the abomasum and abomasal volvulus are well-known disorders of cattle, a comparative evaluation of the clinical, laboratory and ultrasonographic findings of these types of abomasal displacements has not been undertaken. Therefore, the objective of this study was to compare these conditions in a large population of cows. The medical records of 1982 dairy cows with left displaced abomasum (LDA, n = 1341), right displaced absomasum (RDA, n = 338) and abomasal volvulus (AV, n = 303) were searched for the results of clinical, laboratory and ultrasonographic evaluations.

RESULTS

The main clinical findings were an abnormal demeanour in 48.2% of the cows, reduced rumen motility in 89.7% and decreased intestinal motility in 61.1%. Ballottement and simultaneous auscultation and percussion and simultaneous auscultation were positive on the left side in 96.9% of the cows with LDA and on the right in 98.5% of the cows with RDA and in 99.3% of the cows with AV. Ultrasonography was useful for diagnosing LDA in 97.9% of the cows and RDA/AV in 90.2% of the cows. The laboratory findings characteristic of abomasal reflux syndrome varied in severity; 83% of the cows had hypokalaemia, 67% had increased rumen chloride concentration, 67% had an increased base excess and 50% had haemoconcentration. Based on the clinical signs, a definitive diagnosis was made in 75.0% of the cows with LDA and in 22.5% of the cows with RDA/AV. Ultrasonography was required for a definitive diagnosis in another 22.0% of the cows with LDA and in 53.0% of the cows with RDA/AV. Laparotomy or postmortem examination was required for reliable differentiation of RDA and AV.

CONCLUSIONS

LDA, RDA and AV differ with respect to the severity and the frequency of several abnormal clinical, laboratory and ultrasonographic findings as well as the methods required for a diagnosis.

Ultrasonographic documentation of type-3 abomasal ulcer in a cow with left displacement of the abomasum

Background

Ultrasonographic documentation of perforated abomasal ulcer has not been published till now. This report describes the clinical, ultrasonographic and postmortem findings in a Jersey cow with type-3 abomasal ulcer and left displacement of the abomasum (LDA).

Case report

The main clinical findings were abnormal demeanour, rumen atony and tympany, positive foreign body tests, positive auscultation and simultaneous ballottement on the left side, abdominal guarding and loss of negative pressure in the abdominal cavity. The tentative diagnosis was peritonitis and LDA. Abdominal ultrasonography produced images typical of LDA, and in one location between the abdominal wall and abomasum there was a layer of fibrin, a fibrin clot, a break in the abomasal contour, suggestive of a perforated ulcer, and partial obstruction of this gap with fibrin. The diagnosis of perforated abomasal ulcer with subsequent peritonitis was confirmed during postmortem examination.

Conclusions

The examination of this case shows that under certain circumstances, ultrasonographic imaging of a perforated abomasal ulcer in a cow is possible. Antemortem diagnosis of type-3 abomasal ulcer is preferable to relying on exploratory laparotomy and/or post-mortem examination.

Diagnostic performance of ultrasonography in clinical management of dairy cattle identified with left-sided ping sounds

Objectives:

Left displaced abomasum (LDA) is a common postparturient condition of high yielding dairy cattle. The diagnosis of LDA is challenging and has historically been based on findings that are not specific to the condition. The objective of the current study was to investigate the diagnostic performance of ultrasonography (USG) in the clinical management of dairy cows identified with left-sided ping sound postpartum.

Materials and methods:

Cows with reduced appetite postpartum and had audible left-sided ping sounds on abdominal auscultation were eligible to be prospectively recruited onto the study. The results of clinical findings and abdominal USG were recorded along with milk β-hydroxybutyrate levels, pH levels of abomaso/rumenocentesis samples, and findings on exploratory laparotomy. The diagnostic performance of USG and other clinical investigations was assessed by calculating the test sensitivity and specificity using exploratory laparotomy as a gold standard test.

Results:

A definitive diagnosis of LDA was made in 23 cows, 8 cows were diagnosed with peritonitis, and 4 cows with frothy tympany. The USG findings that were consistent with LDA were present in all cattle diagnosed with LDA at exploratory laparotomy. The USG findings over the past three intercostal space characteristics of LDA, however, were also present in five cases subsequently diagnosed with peritonitis and in all cases diagnosed with frothy tympany on exploratory laparotomy. The pH of abdomaso/rumenocentesis samples yielded the highest diagnostic accuracy (97.14%) as a single test in the current study.

Conclusions:

USG over the left abdominal wall despite being a highly sensitive test for the diagnosis of LDA has limitations as a diagnostic tool due to suboptimal specificity.

Ultrasonographic findings in cows with left displacement of abomasum, before and after reposition surgery

Background

The natural incidence of left displacement of abomasum (LDA) in dairy cows was high. The diagnosis of LDA usually relies on characteristic physical exam findings but that transabdominal ultrasound is a useful technique that has been applied to the diagnosis of gastrointestinal diseases of dairy cows in equivocal cases.

Methods

Forty dairy cows with LDA were clinically and ultrasonographically examined to determine the position and the echogenic property of the abomasum. The cows were examined ultrasonographically on the left side, from the 9th intercostal space (ICS) to the 12th ICS as well as the ventral left abdomen before and after reposition surgery.

Results

The vital signs were within normal range in most of the cows and the ‘pinging’ were clearly heard in 37 cows. The abomasal gas cap was visualized from the 9th to 12th ICS in 37 cows and characterized by reverberation artifacts. The abomasal ingesta appeared as homogeneous hypoechoic fluid with scattered hyperechoic foci and were mainly visible in the median region and ventral region of the 9th to 11th ICS in 35 cows. The pyloric canal was detected from the ventral left abdomen wall in 30 cows and appeared as a loop with hypoechogenic wall and echogenic luminal contents in cross section.

Conclusion

These typical ultrasonograms, including reverberation artifacts, homogenous hypoechoic structures, are important diagnostic feature in ultrasonography of LDA. Furthermore, the circular acoustic image structure of the pyloric canal is an important characteristic of LDA, so it can be used as an important diagnostic basis of LDA.

Diagnostic Approach to the Acute Abdomen

The acute abdomen is a term used to characterize an animal presented as an emergency, in a more or less severe critical state, and for which medical and possibly surgical treatment will be necessary. To succeed, the clinician should use a systematic approach, have an excellent knowledge of the bovine abdominal anatomy, and have a good understanding of the pathophysiology of abdominal pain. Good clinical judgment, critical analysis, and good client communication skills are also essential. This article presents and discusses those necessary skills in the context of field practice.

Fluoroscopic observation of the development of displaced abomasum in dairy cows

To clarify the mechanisms underlying the development of displaced abomasum (DA), we repositioned DA in 12 cows by rolling and observed the course of redisplacement using X-ray fluoroscopy. Displacement of the abomasum was observed to follow three patterns: displacement to the left side of the abdominal cavity through the gap formed at the reticulum, atrium of the rumen and ventral sac of the rumen (n=7); displacement to the left side after cranial movement along the diaphragm (n=3); displacement to the right side after cranial movement along the diaphragm (n=2). These differences were considered to be associated with the rumen volume. To the best of our knowledge, this is the first study reporting the visual observation of the course of DA in dairy cows.

Left Displacement of the Abomasum in 4 Beef Calves

Background

Little is known about the occurrence rate, underlying etiology or treatment of left displacement of the abomasum in beef calves.

Objective

Describe the clinical presentation, diagnosis and treatment of left displacement of the abomasum in 4 beef calves.

Animals

Four client‐owned beef breed calves with left displaced abomasum (LDA).

Methods

Retrospective case series. Hospital medical records were reviewed to identify all beef breed cattle under the age of 6 months diagnosed with LDA.

Results

Four beef calves were treated for left displacement of the abomasum. All four had a history of decreased appetite and left‐sided abdominal distention. Two had recently been treated for necrotic laryngitis and one was being treated for clostridial abomasitis. Ultrasonography confirmed the abomasum to be displaced between the rumen and the left body wall in all calves. The calves were initially treated by rolling to correct the abomasal displacement. The abomasum redisplaced in 3 of 4 calves within 1 hour to 6 days; 1 calf developed a mesenteric volvulus. A right paramedian abomasopexy was performed in all cases. Three of 4 calves grew well and remained in the herd 6–18 months later; 1 calf was euthanized because of complications associated with necrotic laryngitis.

Conclusions and clinical importance

Left displacement of the abomasum should be considered as a differential diagnosis for beef calves with abdominal distention. Concurrent necrotic laryngitis can increase the risk of abomasal displacement in beef calves. Treatment should include surgical correction as rolling is not curative and might be associated with mesenteric volvulus.

Left abomasal displacement between the uterus and rumen during bovine twin pregnancy

Here, we describe two cases of left displaced abomasum (LDA) in Holstein cattle at 6 and 9 months of twin gestation. Clinical examination revealed signs of proximal ileus with marked abdominal distension, but no ping sounds. An unusually high position of the gravid uterine horn on the left side was observed with ultrasound. Left exploratory laparotomy confirmed that the abomasum was displaced to the left and entrapped between the rumen and twin gravid uterine horn. A left surgical approach was necessary to correct the condition. Both animals recovered and gave birth to healthy twins. The present cases indicate that the subomental position of a heavy twin gravid uterine horn is a possible mechanical cause of LDA.

Ultrasonography of the gastrointestinal tract in cattle

Ultrasonography is an ideal diagnostic tool for investigating gastrointestinal disorders in cattle. In animals with traumatic reticuloperitonitis, inflammatory fibrinous changes and abscesses can be imaged. Ultrasonography can be used to assess the size, position, and contents of the abomasum. This article describes the ultrasonographic techniques used for examination of the reticulum, rumen, omasum, abomasum, small intestine, and large intestine. The normal findings are presented followed by a description of the most important diseases of these organs.

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.

Diagnostic ultrasonography in ruminants

The use of diagnostic ultrasound equipment is becoming widespread within various sectors of veterinary practice. Ultrasonographic examination has several advantages over other imaging modalities and it can be applied in hospital and ambulatory settings. It has the potential for widespread use in the diagnosis of disorders of several body systems in food animal species. This article describes its application to gastrointestinal, hepatobiliary, cardiothoracic, urogenital, and umbilical disorders. Normal and abnormal findings are portrayed and discussed. Accurate and timely use of this diagnostic modality requires a modest amount of training and practice, but it allows for relatively rapid, inexpensive, and noninvasive acquisition of clinically relevant data.

A new method for detecting the abomasal position and characteristics of movement at the onset of the left displacement of the abomasum in cows

A new method has been developed by us to observe the movements of the abomasum by using a magnet and digital magnetometer. Four cows with left displacement of the abomasum underwent conventional correction by rolling without tacking. A doughnut-type magnet was sutured to the pyloric region in a routine operation. The same was done in three control cows. The position of the pyloric region was observed with a digital magnetometer from outside the cow's body. The magnets in the pyloric region of the control cows were located at the right side of the abdominal cavity at 10-30 cm anterior to the udder base, and moved slightly in various directions within the span of a day. On the other hand, the magnets in the pyloric region of cows with abomasal displacement moved widely in the abdominal cavity from the normal right side to the abnormal left front side. A large movement of the magnet from the normal right side to the abnormal left side of the abdominal cavity was observed within 12 h of the onset of abomasal displacement.

Development, advances and applications of diagnostic ultrasound in animals

Ultrasound has many industrial applications but it was first introduced as a medical diagnostic aid in the 1940s with its first veterinary application, the detection of ovine pregnancy, being reported in 1966. Since then, improvements in equipment quality combined with an increased awareness of the benefits of ultrasound as an imaging technique have led to its widespread use in the veterinary field. Recent advances in computer technology have significantly influenced equipment design and the miniaturization of transducers allows intra-operative and intra-vascular applications. Software advances have improved the ability to manipulate and process data, leading to an increased amount of information being obtained from each examination and the advent of 'remote diagnosis'. Ultrasound guided interventional techniques can now be used for diagnostic or therapeutic purposes. Many of these developments have been introduced by equipment manufacturers but have found specific applications in the veterinary field. Ultrasound is currently employed in a very diverse range of situations, not just as a diagnostic tool in the routine clinical workup of a range of species, but also for disease screening, conservation projects, commercial services, herd management and clinical research.

Ultrasound as a decision-making tool in abdominal surgery in cows

In many patients, abdominal ultrasonography is an excellent diagnostic and prognostic tool. It aids in deciding whether the animal should undergo surgical or medical treatment or be slaughtered. This is particularly true in cattle with traumatic reticuloperitonitis (in combination with radiography of the reticulum) or with a tentative diagnosis of left or right displacement of the abomasum. Ultrasound also is an excellent aid for identification of ileus of the small and large intestine, liver abscesses, cholestasis, various urinary tract disorders, and the different forms of ascites.

Ultrasonographic measurement of abomasal volume, location, and emptying rate in calves

OBJECTIVE

To develop and validate an ultrasonographic method for measuring abomasal volume, location, and emptying rate in suckling calves.

ANIMALS

9 male Holstein calves < 40 days of age.

PROCEDURE

Before and after calves were fed different volumes of milk replacer or 2 L of oral electrolyte solutions, ultrasonographic measurements of abomasal dimensions (width, length, and height) were obtained by applying a 3.5-MHz sector probe to the ventral aspect of the abdomen in the transverse and sagittal planes. Abomasal volume was calculated from the ultrasonographic measurements by modeling the abomasum as an ellipsoid and by use of a power exponential equation to calculate the half-time of abomasal emptying (t1/2).

RESULTS

Preprandial abomasal volume was 20 to 137 mL. All 3 abomasal dimensions increased during feeding and after suckling, and the abomasum was symmetrically located about the midline of the ventral aspect of the abdomen. Strong linear relationships were identified between ultrasonographic and suckled volumes, between ultrasonographic and scintigraphic heights, and between ultrasonographic and scintigraphic lengths. Ultrasonographic t1/2 was linearly related to scintigraphic t1/2; the latter is regarded as the gold standard measure of gastric emptying rate.

CONCLUSIONS AND CLINICAL RELEVANCE

Ultrasonographic evaluation of the abomasum appears to provide a practical, rapid, noninvasive, and accurate method for determination of abomasal volume, location, and emptying rate in suckling calves.

Ultrasonography in gastrointestinal disease in cattle

Ultrasonography is an ideal diagnostic tool for investigating gastrointestinal disorders in cattle. It is performed on standing non-sedated cattle using a 3.5 MHz linear transducer. In animals with traumatic reticuloperitonitis, inflammatory fibrinous changes, and abscesses can be imaged; however, magnets and foreign bodies are difficult to visualize because of the gas content of the reticulum. Ultrasonography can be used to assess the size, position and contents of the abomasum. Percutaneous ultrasound-guided abomasocentesis can be performed to evaluate the nature and chemical composition of its contents. In left displacement of the abomasum, the abomasum is seen between the left abdominal wall and the rumen. It contains fluid ingesta ventrally and a gas cap of varying size dorsally. Occasionally, the abomasal folds are seen in the ingesta. In cattle with right displacement of the abomasum, the liver is displaced medially from the right abdominal wall by the abomasum, which has an ultrasonographic appearance similar to that described for left displacement. Motility and diameter of the intestine are the most important criteria for ultrasonographic assessment of ileus. However, the cause of the ileus is rarely determined using ultrasonography. In cases with ileus of the small intestine, there is at least one region of dilatation of the intestine and motility is reduced or absent. In cattle with caecal dilatation, the caecum can always be imaged from the right lateral abdominal wall. The wall of the caecum closest to the transducer appears as a thick, echogenic, semi-circular line.