Computed tomography of the abdomen in Saanen goats: I. Reticulum, rumen and omasum

Abstract

Computed tomography of the abdomen in Saanen goats: I.reticulum, rumen and omasum Computed tomography of the abdomen in Saanen goats: I. reticulum, rumen and omasum AbstractComputed tomography (CT) of the reticulum, rumen and omasum was carried out in 30 healthy goats and the images were compared to corresponding body sections obtained at postmortem. A multidetector CT was used to examine goats in sternal recumbency. A setting of 120 KV and 270 mA was used to produce 1.5-mm transverse slices from the fifth thoracic vertebra to the sacrum. Soft tissue structures were assessed in a soft tissue with a window width (W) of 400 Hounsfield Units (HU), and a window level (L) of 40 HU. The layering of the ruminal contents was assessed in an ingesta window with a W of 1500 HU and an L of 30 HU. After subjective evaluation, the size of the rumen and omasum, the thickness of the walls of the reticulum, rumen and omasum and the height of the gas cap and fibre and liquid phases of the rumen were measured. Fifteen goats were euthanised after CT examination, placed in sternal recumbency and frozen at -18 ºC for three to 10 days. Thirteen goats were then cut into 1.0-to 1.5-cm-thick transverse slices. One goat was cut in dorsal-plane slices and another in sagittal slices. The structures in the CT images were identified by using the corresponding anatomical slices. et al., 2008a, 2008b, 2009a, 2009b). The methods used to diagnose disorders of these organs include 50 physical examination, haematologic and serum biochemistry analyses, faecal analysis, radiography 51 and ultrasonography (Steininger, 2009; Braun und Steininger, 2010; Jacquat, 2010 After subjective evaluation, the various structures were measured using a window that provided the Results 118In all animals, the reticulum, rumen and omasum could be identified on all anatomic sections and the 119 corresponding CT images (Fig. 1). The reticulum and rumen could be seen between the fifth thoracic vertebra and the sacrum; both 123 organs were consistently seen between the eighth thoracic vertebra and the fifth lumbar vertebra in all 124 the goats. In the transverse plane, the reticulum appeared as a round structure and was almost 125 completely filled with ingesta except for an area of gas in the dorsal aspect (Fig. 2). The reticular 126 structure of the mucosa was seen in the gas-filled dorsal region of the reticulum. The mean thickness 127 of the reticulum wall was 0.2 cm ( Table 1). The reticulum bordered the lungs via the diaphragm (not 128 visible) craniodorsally, the left lobe of the liver on the right and the apex of the heart cranioventrally. 129In the sagittal plane the reticulum and heart, separated by the diaphragm, were seen immediately 130 adjacent to each other over a distance of a few centimetres (Fig. 3), and dorsal to this area of contact (Fig. 4) and the vertical grooves divided the anterior and 138 the two posterior blind sacs from the remaining main part of the rumen (Fig. 5). The craniocaudal 139 extent of the rumen was best evaluated in the sagitta...

Ultrasonography of the rumen of dairy cows

“…Considering the difficulties encountered in a relatively large number of cows investigated, we conclude that reliable ultrasonographic differentiation of fibre mat and ventral fluid phase in cows is the exception. This is in contrast to computed tomography, which allowed unequivocal differentiation of the two layers in calves [6] and goats [5]. However, despite this limitation, ultrasonographic findings of the rumen content supplement clinical findings; tympany caused by eructation problems can be quantified and possibly liquefaction of rumen contents, which is characteristic of grain overload, can be detected.…”

“…Radiography is not suitable for the examination of the entire rumen because of the size of the organ. Although computed tomography has been used successfully in goats and calves to accurately measure the rumen and the dimensions of the ingesta layers [5,6], this imaging technique is limited to the examination of the head and legs in mature cattle because of the disproportion between the size of the equipment and the size of the patient [7]. In contrast, ultrasonography has been used for ruminal examination in calves [8] as well as mature cows [9,10].…”

Dry matter and digesta particle size gradients along the goat digestive tract on grass and browse diets

“…This experiment was part of a study on the abdominal anatomy (Braun et al., ,b,c) and digestive physiology of goats (Codron et al., ; Zeitz et al., ) and performed under licence Zurich 69/2008 of the cantonal veterinary office. Ten female adult non‐lactating Saanen goats were kept in groups in indoor enclosures (app.…”

Variability in microbial population and fermentation traits at various sites within the forestomach and along the digestive tract as assessed in goats fed either grass or browse

“…The experiment was approved by the cantonal veterinary office (ZH 69/2008). After 20 days on the experimental feed, the goats were fasted for about 12 h, immobilised with xylazine/ketamine for a different part of this study (Braun et al, 2011), and euthanised with potassium chloride. Owing to the extensive sampling program, only one or two individuals were euthanised per day; the difference between the first and the last animal of a dietary treatment group did not exceed 5 days.…”

“…Goats were immediately frozen at -18°C in sternal recumbency to retain the internal structures of the digestive tract of the living animal. Later, the abdomen of frozen animals was cut transversely into slices of approximately 1.5 cm thickness (Braun et al, 2011). These frozen slices were used to obtain samples from representative sections of the GIT and stored at -20 °C before analysis.…”