[Repeated drenching of calves - -Ultra-sonographic findings of the -reticulum and abomasum and -short-term -effects on pH and -D-lactate in rumen fluid and blood]. / Wiederholtes Drenchen von Kälbern ­ Ultraschallbefunde an Haube und Labmagen sowie kurzfristige Auswirkungen auf pH-Wert und D-Laktat in Pansensaft und Blut.

INTRODUCTION: An oesophageal tube feeder was used to administer milk to six clinically healthy calves every 12 hours for a total of three feedings. The calves were seven to nine days of age, and each feeding consisted of a volume of milk that was 6 % of the body weight of the calves. The reticulum and abomasum were scanned ultrasonographically before, during and after drenching. Blood samples for D-lactate determination and venous blood gas analysis were collected at -12, 0 (first drenching), 6, 12 (second drenching), 18, 24 (third drenching), 30 and 36 hours. Ruminal fluid was collected for measurement of pH and D-lactate concentration at -12 and 36 hours. Based on simultaneous ultrasonographic examinations of the reticulum and abomasum, some of the force-fed milk flowed into the reticulum and some directly into the abomasum; both organs contained milk immediately after drenching. Drenching led to ruminal acidosis evidenced by a significant decrease in median pH from 7,0 (6,0 - 7,0) to 4,5 (3,0 - 5,0) and a 93-fold increase in median D-lactate concentration from 0,39 (0,14 - 1,33) to 36,3 (17,9 - 53,3) mmol/l but it did not cause metabolic acidosis. Based on these findings, we concluded that milk administered to calves via an oesophageal tube feeder flows into the reticulum and abomasum simultaneously and three force feedings 12 hours apart cause acute ruminal acidosis, which was not accompanied by metabolic acidosis in the short term.

INTRODUCTION: Une sonde d'alimentation œsophagienne a été utilisée pour administrer par trois fois du lait à six veaux cliniquement sains toutes les 12 heures. Les veaux étaient âgés de sept à neuf jours, et chaque repas comprenait un volume de lait correspondant à 6 % de leur poids corporel. Le réticulum et la caillette ont été examinés par ultrasons avant, pendant et après le drenchage. Des échantillons de sang pour la détermination du D-lactate et pour l'analyse des gaz du sang veineux ont été prélevés à ­12, 0 (premier drenchage), 6, 12 (deuxième drenchage), 18, 24 (troisième drenchage), 30 et 36 heures. Le jus de panse a été prélevé pour mesurer le pH et la concentration de D-lactate à ­12 et 36 heures. D'après les examens ultrasonographiques simultanés du réticulum et de la caillette, une partie du lait administré s'est écoulée dans le réticulum et une autre directement dans la caillette : les deux organes contenaient du lait immédiatement après le drenchage. Le drenchage a entraîné une acidose ruminale mise en évidence par une diminution significative du pH médian de 7,0 (6,0 ­ 7,0) à 4,5 (3,0 ­ 5,0) et une concentration médiane de D-lactate 93 fois plus élevée de 0,39 (0,14 ­ 1,33) à 36,3 (17,9 ­ 53,3) mmol/l, mais il n'a pas provoqué d'acidose métabolique. Sur la base de ces résultats, nous avons conclu que le lait administré aux veaux par l'intermédiaire d'une sonde d'alimentation œsophagienne s'écoule simultanément dans le réticulum et la caillette et que trois gavages à 12 heures d'intervalle provoquent une acidose ruminale aiguë qui ne s'est pas accompagnée d'une acidose métabolique à court terme.

Integrative approach to a patient following rumenotomy - case report / [Abordagem integrativa ao paciente submetido à ruminotomia - relato de caso]

Concern with antimicrobial resistance in animal production systems increases the interest toward integrative therapies. The objective of the present report was to report an integrative approach to a goat undergoing rumenotomy. A goat with ruminal acidosis underwent rumenotomy, corrective rumen suture, moxibustion, and treatment of the surgical wound (TFO) with sugar. In the first twenty days, acupuncture was performed on ST36, indirect moxibustion on Sp6 and CV8, and TFO with antibiotic ointment and sugar. The wound contracted 2cm, there was gradual return of ruminal dynamics, and moderate pain. Acupuncture continued from D21 to D50 on Yin tang, BL13, BL20, BL23, and BL22. Although there was drainage of ruminal fluid, the wound contracted 4cm during this period, pain was absent, and ruminal dynamics normal. During the last thirty days, the acupuncture technique surround the dragon was used and BL13 point needled, with complete closure of the wound. The TFO from D21 was performed solely with sugar. During treatment, there was modulation of the inflammatory response, with formation of granulation tissue and neovascularization. On D84, fibrinogen was 100mg/dL. The authors conclude that the use of sugar, acupuncture, and moxibustion contributed to return of normal ruminal motility, wound contraction, and complete tissue reepithelization.(AU)

A preocupação com a resistência antimicrobiana nos sistemas de produção animal aumenta o interesse pelas terapias integrativas. Objetiva-se relatar a abordagem integrativa ao paciente caprino submetido à ruminotomia. Uma cabra com acidose ruminal foi submetida à ruminotomia, ruminorrafia, moxabustão, acupuntura e tratamento da ferida operatória (TFO) com açúcar. Nos primeiros vinte dias realizou-se acupuntura em ST36, moxa indireta em Sp6 e CV8, TFO com pomada antibiótica e açúcar. A ferida contraiu 2cm, houve retorno gradual da dinâmica ruminal e dor moderada. A acupuntura continuou de D21 a D50 em Yin tang, BL13, BL20, BL23 e BL22. Apesar da ferida drenar fluido ruminal teve contração de 4cm nesse período, ausência de dor e retorno fisiológico da dinâmica ruminal. Nos últimos trinta dias foi realizada a técnica de acupuntura cercar o dragão e punturou-se o ponto BL13, com fechamento completo da ferida. O TFO a partir do D21 foi realizado somente com açúcar. Durante tratamento houve modulação da resposta inflamatória com formação de tecido de granulação e neoangiogênesse, o D84 revelou fibrinogênio 100mg/dL. Conclui-se que a utilização do açúcar, acupuntura e moxabustão contribuíram para o retorno fisiológico da motilidade ruminal, contração da ferida e completa reepitelização tecidual.(AU)

A retrospective study on transabdominal ultrasound measurements of the rumen wall thickness to evaluate chronic rumen acidosis in beef cattle.

BACKGROUND: Chronic and subacute rumen acidosis are economically important in the beef industry. The aim of this study was to evaluate the potential suitability of the transabdominal ultrasonographic examination of the ruminal wall to diagnose chronic rumen acidosis in beef cattle compared to direct measurement of ruminal pH, as a fast non-invasive tool to be used in field condition. Ultrasonographic examination of the rumen was conducted in 478 beef cattle before rumenocentesis (chronic rumen acidosis group = pH ≤ 5.8; healthy group = pH ≥ 5.9). Rumen wall ultrasound measurements included rumen wall thickness (RWT) and rumen mucosa and submucosa thickness (RMST). RESULTS: The Analysis of Variance showed the high significant effect of the pH class for RWT and RMST (P < 0.001). Spearman RANK correlation analysis showed interaction between rumen pH and RWT (- 0.71; P < 0.0001) and RMST (- 0.75; P < 0.0001). A significant Spearman's correlations were found between volatile fatty acids (VFA) and RWT and RMST. The differentiation efficiency of RWT between healthy and chronic rumen acidosis groups, as a result of the receiver operator curve (ROC) analysis, was quite good with an area under the receiver operator curve (AUROC) of 0.88: P < 0.0001; 95% CI: 0.83-0.98. Using a cut-off value of > 8.2 mm. The differentiation efficiency of RMST between healthy and chronic rumen acidosis groups, as a result of ROC curve analysis, was good with an AUROC of 0.90: p < 0.0001; 95% CI: 0.85-0.94. Using a cut-off value of > 5.3 mm. CONCLUSIONS: In this study, the thickening of RWT and RMST is correlated with the changes of ruminal pH. Transabdominal rumen ultrasound has the potential to become a powerful diagnostic tool useful to identify fattening bulls affected by chronic rumen acidosis.

Diagnosis and treatment of foreign bodies swallowing syndrome in camels (Camelus dromedarius) with special reference to the role of mineral deficiency.

This study describes the clinical presentation of ruminal and reticular foreign body syndrome (RRFBS), and evaluates the effect of mineral deficiency on its occurrence in dromedary camels. Thirty dromedary camels were divided into two groups. Group 1 (control) included 10 apparently healthy she-camels. Group 2 consisted of twenty dromedary camels diagnosed with RRFBS on the basis of clinical, ultrasonographic, hematological, and biochemical examinations. Clinical findings showed decreased appetite and milk yield, tympany, and gradual body weight loss. Ultrasonographic examinations revealed the presence of hyperechoic material with variable degrees of shadowing. Hematological evaluation showed a significant (P<0.05) decrease of the total erythrocyte and lymphocyte count and a significant increase of neutrophils in the camels with RRFBS compared to the controls. Biochemical tests showed a significant elevation in the activity of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), creatine kinase (CK), glucose, creatinine, and blood urea nitrogen and a significant decrease of sodium, chloride, potassium, cobalt, iron, and selenium in the camels with RRFBS compared to the controls. Rumenotomy was performed on the 20 camels as a surgical intervention for treating the RRFBS. By the 6th month postoperatively, all surgically treated camels had completely recovered except for one with tympany and slight swelling in situ. In conclusion, trace element deficiency might play an important role in the occurrence of foreign body ingestion syndrome in dromedary camels. Moreover, clinical, ultrasonographic, hematological, and biochemical examinations are considered as tools assisting in the accurate diagnosis, prognosis, and treatment stratagem for RRFBS in camels.

Hot topic: Automated assessment of reticulo-ruminal motility in dairy cows using 3-dimensional vision.

Reticulo-ruminal motility is a well-established indicator of gastrointestinal health in dairy cows. The currently available methods for assessing motility are labor-intensive, costly, and impractical to use regularly for all cows on a farm. We hypothesized that the reticulo-ruminal motility of dairy cows could be assessed automatically and remotely using a low-cost 3-dimensional (3D) camera. In this study, a 3D vision system was constructed and mounted on the frame of an automatic milking robot to capture the left paralumbar fossa of 20 primiparous cows. For each cow, the system recorded 3D images at 30 frames per second during milking. Each image was automatically processed to locate the left paralumbar fossa region and quantify its average concavity. Then, the average concavity values from all images of 1 cow during 1 milking process were chronologically assembled to form an undulation signal. By applying fast Fourier transformation to the signal, we identified cyclic oscillations that occurred in the same frequency range as reticulo-ruminal contractions. To validate the oscillation identification, 2 trained assessors visually identified reticulo-ruminal contractions from the same 3D image recordings on screen. The matching sensitivity between the automatically identified oscillations and the manually identified reticulo-ruminal contractions was 0.97. This 3D vision system can automate the assessment of reticulo-ruminal motility in dairy cows. It is noninvasive and can be implemented on farms without distressing the cows. It is a promising tool for farmers, giving them regular information about the gastrointestinal health of individual cows and helping them in daily farm management.

Ultrasonographic examination of the oesophageal groove reflex in young calves under various feeding conditions.

The oesophageal groove reflex was examined in 6 milk-fed Holstein Friesian calves once weekly during the first 17 weeks of life. Additionally, the effect of different feeding methods (bucket, different nipple positions and openings), different milk temperatures (20, 30, 39, 45°C) and milk replacer concentrations (100, 125, 150 grams/litre of water) on oesophageal groove closure was investigated. The reticulum and abomasum were examined ultrasonographically using a 5.0-MHz convex transducer before, during and after feeding, and the oesophageal groove reflex was considered to be functional when milk was seen entering the abomasum during feeding. The reflex was consistently induced throughout the study period in all calves at all examinations and under all experimental conditions. However, it should not be assumed that feeding technique can be neglected in unweaned calves because suboptimal feeding management has been linked to various digestive disorders.

Ultrasonographic assessment of reticuloruminal motility in 45 cows.

The goal of this study was to investigate the feasibility of ultrasonographic assessment of reticuloruminal motility in 45 healthy cows. The transducers of five ultrasound machines were connected to a digital video recorder and placed simultaneously at five sites on the left side of the cows to scan the reticulorumen (reticulum; ruminal atrium; dorsal sac of the rumen; left longitudinal groove; ruminal recess, caudodorsal and caudoventral blind sacs). The video streams from all five ultrasound machines were recorded synchronously with the same time line and displayed on a single monitor. Time 0 was defined as the start of a biphasic reticular contraction. The reticulum was visualised in all cows and had 11.0 ± 2.12 biphasic contractions in 9 min. The ruminal atrium was visualised in 40 (89%) cows and had 10.7 ± 2.10 contractions in 9 min, which started at the time point 5.0 ± 0.83 sec and lasted 7.0 ± 2.14 sec. Contractions of the dorsal sac of the rumen, visible in all cows, were visualised in 29 (64%) cows. There were 9.5 ± 1.8 contractions in 9 min that started at the time point 4.0 ± 0.85 sec and lasted 8.2 ± 1.04 sec. The left longitudinal groove was seen contracting in 39 (87%) cows. There were 10.2 ± 1.98 contractions in 9 min that started at the time point 4.1 ± 1.81 sec and lasted 7.8 ± 1.19 sec. Contractions of the ventral sac of the rumen (ruminal recess) were seen in 31 (69%) cows. There were 7.5 ± 2.59 contractions in 9 min that started at the time point 14.3 ± 4.30 sec. Contractions of the caudodorsal and caudoventral blind sacs were seen in 34 (76%) cows. There were 9.0 ± 2.75 (1.0 ± 0.31) contractions/min and 9.4 ± 2.09 (1.0 ± 0.23) contractions/min of the dorsal and ventral blind sacs, and they started at the time points 6.2 ± 1.32 sec and 21.3 ± 6.20 sec, respectively. Primary contraction cycles were seen in all cows and secondary cycles in 22 (49%) cows. The former were complete in 37 (82%) cows and incomplete in 8 (18%). There were 11.0 ± 2.12 primary and 4.5 ± 2.15 secondary cycles in 9 min, and the ratio between primary and secondary cycles averaged 2.4:1. Ultrasonography is suitable for the assessment of reticuloruminal motility

Transabdominal ultrasonography of the ruminal mucosa as a tool to diagnose subacute ruminal acidosis in adult dairy bulls: a pilot study.

Subacute rumen acidosis (SARA) is frequently encountered in ruminants on high-concentrate rations and characterized by mild to moderate rumen pH depression. Although the measurement of rumen pH is considered as a gold standard approach to diagnose SARA, rumen fluid collection is conceived as a cumbersome and invasive procedure. In the present study, the suitability of transabdominal ultrasonography to identify structural changes of the rumen mucosa associated with SARA was explored. Five adult rumen canulated bulls previously adjusted to a roughage-based ration were switched in 10-day intervals to rations with increasing concentrate content. Seven rations with a concentrate content ranging from 5% to 95% were fed. The rumen pH and rumen mucosal thickness were measured at the end of each 10-d feeding period. The left flank was divided into 12 acoustic windows and the mean rumen mucosal thickness for each acoustic window determined for each ration. Repeated measure ANOVA and stepwise regression analyses were conducted. Increasing the dietary concentrate content resulted in thickening of rumen mucosa which was most pronounced in the upper part of the ventral rumen sac and the least pronounced in the uppermost and lowermost parts of the rumen. The intersection of a horizontal line going through the costochondral junction and a vertical line coming from the third lumbar vertebra was found to be most suitable to identify animals with rumen pH < 5.5 at 4 h post feeding. We conclude that transabdominal ultrasonography of the rumen mucosa has the potential to be a suitable, non-invasive diagnostic tool to identify adult ruminants with SARA.

Ultrasonographic examination of the abdomen of the goat. I. Reticulum, rumen, omasum, abomasum and intestines.

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.

Ultrasonography of the rumen of dairy cows.

BACKGROUND: This study describes the ultrasonographic findings of the rumen in 45 healthy dairy cows. RESULTS: The cows were scanned on both sides using a 5.0 MHz transducer. The dorsal visible margin of the rumen ran parallel to the lung from cranioventral to caudodorsal. It was furthest from the dorsal midline at the 9th intercostal space (48.3 ± 9.24 cm) and closest at the 12th intercostal space (22.4 ± 3.27 cm). The longitudinal groove, which could be clearly identified at all examination sites because it appeared as a triangular notch, formed the ventral margin of the dorsal sac of the rumen. The dorsal sac of the rumen was largest at the caudal flank (40.3 ± 6.33 cm), where it was adjacent to the abdominal wall. The ventral sac of the rumen extended across the ventral midline into the right hemiabdomen and its ventral margin had a largely horizontal craniocaudal course. The height of the ventral sac of the rumen exceeded that of the dorsal sac at all examination sites; the maximum height was measured at the 12th intercostal space (62.6 ± 9.53 cm). The dorsal gas cap, characterised ultrasonographically by typical reverberation artifacts, was visible in all cows from the 12th intercostal space to the caudal flank. It was largest at the 12th intercostal space (20.5 ± 7.03 cm). The transition from the gas cap to the fibre mat was marked by the abrupt cessation of the reverberation artifacts. It was not possible to differentiate a fibre mat and a ventral fluid phase. The rumen could be imaged from the right side in 21 cows (47%). CONCLUSIONS: Ultrasonography is well suited for the detailed examination of the rumen of cows. The reference values obtained from this study add to the diagnostic tools that are available for the assessment of bovine patients.

Ultrasonography of the rumen in 30 Saanen goats.

This study describes the results of ultrasonographic examination of the rumen in 30 healthy Saanen goats. A linear or convex transducer with a variable frequency of 5 to 13 MHz was used to scan standing, non-sedated goats. The location and size of the rumen, the distance between the wall of the rumen and abdominal wall and the appearance and size of the gas, fibre mat and fluid layers of the ruminal contents were assessed. The rumen was seen as a large organ medial to the left abdominal wall. The wall of the rumen appeared as a thick echogenic line. The longitudinal groove was seen as an echogenic notch, which divided the rumen into the dorsal and ventral sacs. The rumen could be visualized from the 9th to 12th intercostal space (ICS) and flank on the left side in all the goats. The rumen was largest in the 12th ICS at 41.6 ± 5.13 cm and smallest in the 8th ICS at 11.3 ± 4.29 cm. The dorsal sac of the rumen was largest in the left cranial flank (17.4 ± 4.43 cm) and the ventral sac was largest in the 12th ICS on the left (29.1 ± 6.03 cm). In the cranial left flank, the rumen was situated immediately adjacent to the abdominal wall in all the goats. The spleen was located between the rumen and abdominal wall in the 8th to 12 th ICS in many of the goats. The gas, fibre mat and fluid layers of the ruminal contents could be visualized in all the goats. The gas layer was 9.9 ± 3.05 cm, the fibre mat layer 16.0 ± 4.55 cm and the fluid layer 12.2 ± 5.57 cm.

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

Computed 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.

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 evaluation of reticular motility during rest, eating, rumination and stress in 30 healthy cows.

A 3.5 MHz linear transducer was used to assess the motility of the reticulum in 30 healthy, standing, non-sedated cows while they were at rest, eating, ruminating and under stress. The ultrasonographic examinations were made over periods of nine minutes and video recorded for analysis. The reticulum contracted in a biphasic pattern while the cows were resting, eating or stressed. The first contraction was incomplete and was followed by a period of incomplete relaxation. A complete second contraction occurred immediately afterwards, followed by an interval of complete relaxation and the return of the organ to its original position. When the cows were ruminating, a regurgitation contraction, which was incomplete, occurred immediately before the biphasic contraction. The number of reticular contractions in a nine-minute period was largest when the cows were eating (13.9 contractions, or approximately 1.5 per minute) and smallest when they were stressed (9.3 contractions, or approximately 1 per minute). The duration of the first reticular contraction was shortest during rumination (2.4 seconds) and longest when the cows were eating (3.0 seconds). The interval between two biphasic contractions was shortest when the cows were eating (31.6 seconds) and longest when they were stressed (53.8 seconds).

Measurement of the ultrasonic attenuation of fat at high frequency.

RATIONALE AND OBJECTIVES: High-frequency ultrasound devices are often limited by a decreased depth of acoustic imaging caused by the increased attenuation of tissue at high frequencies. We investigated the role of adipose tissue in this phenomenon. METHODS: A substitution technique was used to calculate the ultrasonic attenuation (decibels per centimeter) of fresh samples of sheep rumen, omental fat, and back fat and swine back fat and various concentrations of bovine milk fat at 22 degrees C and 37 degrees C for frequencies of 15 and 20 MHz. RESULTS: The attenuation was significantly higher for sheep adipose tissue than for the intestinal wall, in descending order, omental fat, back fat, and rumen wall (P < 0.01). A correlation was found between bovine milk fat concentrations and attenuation at both frequencies (R2 > 0.9). The attenuation of adipose tissues decreased significantly with an increase in temperature (P < 0.01), whereas the attenuation of sheep rumen showed no significant change (P > 0.1). CONCLUSIONS: The ultrasonic attenuation of fat may contribute to limitations on the use of high-frequency ultrasound in clinical situations in which adipose tissue is present.

Thoracic oesophageal motor activity during eructation in sheep.

Concurrent radiographic and electromyographic observations were made in sheep during naturally occurring eructations. The radiographic field extended from the base of the heart to the cranial region of the rumen. Electromyographic recording was from two sites on the caudal thoracic oesophagus within 20-70 mm of the diaphragm. Passage of gas from the rumen into the oesophagus was followed by passive gaseous distension of the caudal thoracic oesophagus for period of 540 2860 ms (n = 80), at the end of which there was both electromyographic and radiographic evidence of oesophageal contraction. The pattern of radiographic change was indicative of a cranially progressing contraction of the thoracic oesophagus. Movements of the diaphragm observed radiographically during ventilation ceased (at the end of expiration), or became shallower, during the period of oesophageal distension. This resulted in a varying degree of interruption of the rhythm of ventilation. The first inspiration marking a return of ventilation to its former character was deeper than normal. The events during eructation were essentially similar whether the animals were eating, ruminating, or doing neither. When swallowing occurred during eructation it appeared to continue normally, interrupting the train of oesophageal reactions in eructation. Gas sometimes entered the caudal thoracic oesophagus after a mixing contraction of the reticulo-rumen but it was returned to the stomach by a caudally moving oesophageal contraction.

Contrast study of the gastrointestinal tract in the goat (Capra hircus).

Radiographic anatomy of the gastrointestinal tract of the goat (Capra hircus) was studied. Intraluminal contrast medium was used to evaluate the mucosal surfaces of stomach and intestines, and extraluminal contrast medium was used to evaluate the serosal surfaces of organs in the peritoneal cavity.