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BackgroundAssessment of left ventricular (LV) systolic function can be achieved by conventional echocardiographic methods, but quantification of contractility, regional myocardial function, and ventricular synchrony is challenging. The goal of this study was to investigate the applicability of two-dimensional speckle tracking (2DST) to characterize segmental and global wall motion for assessment of LV function and LV synchrony in healthy goats. We aimed to describe the techniques, report normal values of a variety of 2DST indices, and determine the influence of general anesthesia.MethodsProspective study on 22 healthy female Saanen goats (3.7 ± 1.1 y, 60.2 ± 10.5 kg [mean ± SD]). All goats underwent two transthoracic echocardiographic examinations, the first standing and unsedated and the second 7.4 ± 3.5 days later during isoflurane anesthesia and positioned in sternal recumbency. Data analyses were performed offline, blinded, and in random order. Left ventricular longitudinal, radial and circumferential strain and strain rate as well as longitudinal and radial displacement were measured using 2DST methods. Summary statistics were generated and differences of 2DST variables between myocardial segments and treatments (i.e., awake vs. anesthetized) were assessed statistically (alpha level=0.05).ResultsEchocardiographic analyses by 2DST were feasible in all goats and at both time points. Longitudinal systolic strain, strain rate and displacement followed a gradient from apex to base. Absolute systolic strain was generally lower and strain rate was higher in awake goats compared to anesthetized goats. Circumferential and radial indices did not consistently follow a segmental pattern. Generally, peak strain occurred later in anesthetized goats compared to awake goats. General anesthesia did not significantly influence LV synchrony.Conclusions2SDT is a valid method for non-invasive characterization of LV wall motion in awake and anesthetized goats. The results of this study add to the understanding of LV mechanical function, aid in the diagnosis of global and segmental LV systolic dysfunction, and will be useful for future cardiovascular studies in this species. However, effects of anesthesia and species-specific characteristics should be considered when goats are used as animal models for human disease.Electronic supplementary materialThe online version of this article (doi:10.1186/s12947-015-0005-8) contains supplementary material, which is available to authorized users.

Results provided information regarding the ultrasonographic appearance of the liver, caudal vena cava, portal vein, and gallbladder in healthy goats; these data may be useful during examination of goats with suspected liver disease.

Echocardiographic assessment of cardiac structures, dimensions, and mechanical function in goats is poorly documented. The goal of this study was to describe normal findings, establish normal values for two-dimensional (2DE) and M-mode (MME) echocardiography, and investigate the influence of general anaesthesia. Standardized 2DE and MME recordings were obtained on 22 healthy female Saanen goats (3.7 ± 1.1 years [mean ± SD], 60.2 ± 10.6 kg) awake (standing) and during isoflurane anesthesia (sternal recumbency). Cardiac dimensions and function were assessed and compared between treatments (awake vs. anaesthetized). Color Doppler imaging and saline contrast studies served to assess abnormal blood flow patterns. Post mortem examination was performed in a subset of 12 goats. Transthoracic echocardiography was feasible in all goats. Indices of LV systolic function proved to be significantly increased during general anesthesia. The membranous and occasionally echolucent appearance of the oval fossa suggested abnormal interatrial communication in 9 goats. Color Doppler imaging and saline contrast studies proved to be inaccurate to detect interatrial shunting of blood. Post mortem examination confirmed small persistent foramen ovale in only 3 out of 7 goats, in which it had been suspected on echocardiography.

The ultrasonographic appearance, location and size of the spleen in 30 healthy female Saanen goats are described. The intercostal spaces of the left thoracic wall were scanned with a 5.0 MHz linear transducer in standing goats. The appearance of the splenic parenchyma, the position of the ultrasonographically visible dorsal and ventral margins of the spleen and the distance between them, the thickness of the spleen and the diameter of the splenic vessels were determined. The spleen could be visualised in at least one examination position and it always lay between the rumen and abdominal wall. The spleen bordered the lung dorsally and was located adjacent to the left abdominal wall in the last intercostal space and area immediately caudal to the last rib. The spleen had an echogenic capsule, and its parenchyma showed a homogenous fine echotexture / echo pattern throughout the whole visible part of the spleen. The splenic vessels were seen within the parenchyma. The visible dorsal margin of the spleen ran from cranioventral to caudodorsal. The distance from the dorsal margin of the spleen to the midline of the back was greatest in the 8th intercostal space (19.7 ± 4.19 cm) and smallest in the region immediately caudal to the last rib (7.0 ± 1.07 cm). The size of the spleen was smallest in the 8th intercostal space (3.1 ± 1.24 cm) and greatest in the 11th intercostal space (8.7 ± 2.78 cm). The thickness of the spleen ranged from 2.2 ± 1.14 cm caudal to the last rib to 6.4 ± 1.78 cm in the 11th intercostal space.

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This review article summarizes the ultrasonographic findings of the reticulum, rumen, omasum, abomasum and intestines of goats. Ultrasonographic examination is done on both sides with the goat in a standing position using a linear array or convex transducer with a frequency of 5.0 to 7.5 MHz. The shape, contour and motility of the reticulum are assessed; this organ appears as a crescent-shaped structure with a smooth contour immediately adjacent to the diaphragm. There are 0.8 to 2.1 reticular contractions per minute, which may be mono-, bi-and triphasic. The rumen is examined from the 8th to 12th intercostal spaces (ICSs) and flank on the left, and from the 12th ICS and flank on the right. The ruminal wall appears as a thick echoic line. The dorsal and ventral sacs of the rumen are differentiated based on the longitudinal groove, which forms an echoic notch. Differentiation of the dorsal gas cap, fibre mat and fluid layer is not always straightforward and varies among goats. The omasum is examined from the 6th to 11th ICSs on the right. Only the wall closest to the transducer can be imaged and it appears as a crescent-shaped echoic line medial to the liver. The omasal folds and the wall furthest from the transducer cannot be seen. In about two thirds of goats, active omasal motility is apparent as a transient reduction in size of several centimetres, followed by relaxation and return to its original size. There is an average of 1.1 contractions per minute. The abomasum is examined from the ventral midline and the left and right paramedian regions and can always be seen from the ventral midline. In all but a few goats the abomasum is also visible from the left and right paramedian areas. It appears as a heterogeneous, moderately echoic structure with echogenic stippling. The abomasal folds appear as prominent echoic bands in about two thirds of all goats. The small and large intestines are examined on the right from the 8th to the 12th ICSs. Loops of jejunum and ileum are seen mainly in cross-section and have a strong motility. The intestinal content is usually homogeneous and echoic and the diameter of the intestinal loops varies from 0.8 and 2.7 cm. The spiral colon and in many cases also the caecum can be imaged. The former is recognized by its garland-like appearance brought about by the centripetal and centrifugal coils of the intestine. In the spiral colon and the caecum, only the wall closest to the transducer can be imaged because of intraluminal gas. The wall appears as a thick echoic and slightly undulating line 5.6 to 8.0 cm in length. Ultrasonography is an imaging technique that is very well suited for the examination of the gastrointestinal tract of goats. This review article summarizes the ultrasonographic findings of the reticulum, rumen, omasum, 9 abomasum and intestines of goats. Ultrasonographic examination is done on both sides with the goat in a 10 standing position using a linear array or convex transducer with a frequency of 5.0 to 7.5 MHz. The 11 shape, contour and motility of th...

This review article describes the ultrasonographic findings of the liver, spleen, urinary tract and greater omentum that were previously obtained in studies of healthy female Saanen goats. Real-time B-mode ultrasonography and a linear or convex 5.0 to 7.5 MHz transducer are used to scan standing goats from both sides. The urinary bladder and urethra are also examined transrectally. The liver is scanned from the intercostal spaces (ICSs) on the right from dorsal to ventral. The parenchymal pattern consists of numerous fine echoes that are homogenously distributed across the entire organ. The dorsal visible margin of the liver runs parallel to the lung in a cranioventral to caudodorsal direction. The visible extent of the liver is largest in the 7th and 8th ICSs and the maximum thickness is measured in the 10th ICS. The caudal vena cava has a triangular shape in cross section and is seen only at the 11th or 12th ICS. The portal vein is oval to circular in cross section with stellate ramifications into the liver parenchyma. The gallbladder is pear-shaped and sometimes extends beyond the ventral margin of the liver depending on the amount of bile. In most goats, the gallbladder is only seen from the 9th or 10th ICS. The spleen is scanned from the left where it is almost always seen from the 11th and 12th ICSs. The parenchymal ultrasonographic pattern is similar to that of the liver. The splenic vessels are embedded in the parenchyma and are seen in longitudinal or cross section. The kidneys are best visualized from the flank and last two ICSs on the right. The ultrasonographic appearance varies with the sectional plane. In a sagittal plane through the hilus, the parenchyma is homogenous with fine, evenly distributed echoes. The medullary pyramids are seen near the sinus as oval to circular hypoechoic structures. The hyperechoic sinus is at the centre of the kidney. The urinary bladder is best visualized transrectally but can also be seen in many goats from either inguinal region. The content of the bladder is usually anechoic and the diameter ranges from 1.0 to 4.8 cm. The urethra is seen transrectally as two adjacent parallel echoic lines without an apparent lumen.