Computed tomography of the abdomen of calves during the first 105 days of life: I. Reticulum, rumen, omasum and abomasum

Computed tomographic (CT) images of the reticulum, rumen, omasum and abomasum of five healthy Holstein-Friesian bull calves were compared with anatomical transverse cadaver sections of the same calves. The calves were scanned in the transverse plane from the 5th thoracic vertebra to the sacrum six times three weeks apart from birth to 105 days of age. Multiplanar reconstruction was used to create images in sagittal and dorsal planes. After subjective assessment of various anatomical structures, the rumen, omasum and abomasum as well as the ruminal strata (gas cap, fibre mat and fluid phase) were measured. After the last CT scan, all calves were euthanised, and four were kept at -18 °C in sternal position for 14 days. Transverse sections 1.0 to 1.5 cm thick were made from two calves and dorsal and sagittal sections were made from one calf each using a band saw. The CT images and anatomical slices were compared and the structures on the CT images identified. Very clear CT images were obtained from the reticulum, rumen, omasum and abomasum and there was excellent agreement between images and anatomical slices

Computed tomography of the abdomen of calves during the first 105 days of life: II. Liver, spleen, and small and large intestines

Computed tomography (CT) findings of the liver, spleen and intestines of five healthy calves during six examinations in the first 105 days of life were compared with corresponding cadaver slices. The liver was located in the right hemiabdomen adjacent to the diaphragm and right abdominal wall. The caudal vena cava was seen dorsomedially and the portal vein further ventrally. The umbilical vein was seen running from the navel to the liver in all calves in the first scan and in four calves in the second scan. The spleen ran dorsoventrally adjacent to the costal part of the left abdominal wall and appeared sickle-shaped on transverse images. Differentiation of small and large intestines was only possible when the former contained fluid content and the latter gaseous content. The small intestine was in the left hemiabdomen dorsal to the abomasum and caudodorsal to the rumen at the first two examinations. Growth of the forestomachs caused displacement of the small intestine to the right and toward the ventral abdomen caudal to the liver and adjacent to the right abdominal wall. The large intestine was located caudodorsally, and the typical features of the spiral colon were apparent in the dorsal plane. The location of the caecum varied from dorsal to the spiral colon to adjacent to the right abdominal wall with the apex always pointing caudally. The rectum was easily identified in the pelvic region. The size, volume and density of the described organs throughout the study are shown in several tables

Online measurement of motivational processes: introducing the continuous delay aversion test (ConDAT) (in Special issue 'Towards a Neuroscience of Attention-Deficit/Hyperactivity Disorder (ADHD)')

The Continuous Delay Aversion Test (ConDAT), a new computer task for online monitoring and continuously measuring delay aversion (DA), is introduced. DA is a motivational style related to a shortened delay gradient which is proposed as a major endophenotype of attention deficit hyperactivity disorder (ADHD). It is characterised by avoiding or escaping from delay-rich situations despite the prospects of a reward. In each ConDAT trial the rapidly diminishing reward/delay ratio, which tends asymptotically towards zero, is visually presented on the computer screen. The test subject is permanently confronted with the question whether to quit or to continue the trial in the face of the deteriorating reward/time ratio. An elaborated control of stimuli and responses, including the sending of trigger codes to external recording devices, makes the task useful for neurophysiological or brain imaging experiments. Compared to existing tasks, the ConDAT is more flexible and sensitive due to its asymptotic open-ended trials and the interval-scaled output measure. Pilot data give evidence for satisfactory reliability and external validity of the task

The behavioural profile of children with attention-deficit/hyperactivity disorder and of their siblings

The behavioural profiles in N = 69 index children with attention-deficit/hyperactivity disorder (ADHD), N = 32 siblings with ADHD, N = 35 siblings without ADHD, and N = 36 normal controls were compared by the use of standardized parent and teacher rating scales. The four groups were matched by age and IQ. The behavioural profiles of the two ADHD groups were very similar not only in the behavioural domains of ADHD, but also in scales measuring emotional and conduct problems. Siblings without ADHD shared more similarities with normal controls except for more emotional problems. These general trends were stronger in the parent compared to the teacher ratings. These findings indicate that not only ADHD-related but also other behaviours show a strong family aggregation. The informant differences may reflect context dependent differences in child behaviour and contrast effects particularly in parental ratings

Situs ambiguus in a Brown Swiss cow with polysplenia: case report

BACKGROUND: Laterality defects are rare in cattle and usually manifest as asplenia or polysplenia syndrome. These syndromes may be associated with situs ambiguus, which is a dislocation of some but not all internal organs. The objective of this report was to describe the clinical and post-mortem findings including the macroscopic and microscopic anatomy of selected organs in a cow with polysplenia and situs ambiguus. CASE PRESENTATION: A 3.5-year-old Brown Swiss cow was referred to the Department of Farm Animals, Vetsuisse Faculty, University of Zurich, because of poor appetite and recurrent indigestion. A diagnosis of situs ambiguus was based on the results of physical examination, ultrasonography, exploratory laparotomy and post-mortem examination. The latter revealed that the rumen was on the right side and lacked compartmentalisation. There were two spleens, one on the left (26.5 x 12.0 cm) and one on the right (20.5 x 5.5 cm), and the omasum was located craniolateral to the ruminoreticulum on the left. The abomasum was located on the right, although it had initially been displaced to the left. The three-lobed liver occupied the left and central cranioventral aspect of the abdominal cavity (cavum abdominis). Only the right and left hepatic veins (vena hepatica dextra and sinistra) drained into the thoracic segment of the caudal vena cava (vena cava caudalis), and histological changes in the liver were indicative of impaired haemodynamics. The mesojejunum was not fused with the mesentery of the spiral loop (ansa spiralis) of the ascending colon (colon ascendens). The latter was folded and the transverse colon (colon transversum) ran caudal to the cranial mesenteric artery (arteria mesenteria cranialis). Fibrotic constrictions were seen in the lumen of the caecum and proximal loop (ansa proximalis) of the ascending colon. Both kidneys were positioned retroperitoneally in a lumbar position. The lumbar segment of the caudal vena cava did not descend to the liver and instead drained into the right azygous vein (vena azygos dextra). CONCLUSIONS: Recurrent digestive problems and poor production in this patient may have been caused by a lack of rumen compartmentalisation, abnormal abomasal motility, constrictions in the large intestine (intestinum crassum) and fibrosis of the liver. The abomasum had abnormal motility most likely because it was anchored inadequately and only at its cranial aspect to the liver by the lesser omentum (omentum minus) and to the dorsal abdominal wall and rumen by a short greater omentum (omentum majus)

Genetics of preparation and response control in ADHD: the role of DRD4 and DAT1

BACKGROUND Difficulties with performance and brain activity related to attentional orienting (Cue-P3), cognitive or response preparation (Cue-CNV) and inhibitory response control (Nogo-P3) during tasks tapping executive functions are familial in ADHD and may represent endophenotypes. The aim of this study was to clarify the impact of dopamine receptor D4 (DRD4) and dopamine transporter (DAT1) gene polymorphisms on these processes in ADHD and control children. METHODS Behavioural and electrophysiological parameters from cued continuous performance tests with low and high attentional load were assessed in boys with ADHD combined type (N = 94) and controls without family history of ADHD (N = 31). Both groups were split for the presence of at least one DRD4 7-repeat allele and the DAT1 10-6 haplotype. RESULTS Children with ADHD showed diminished performance and lower Cue-P3, CNV and Nogo-P3 amplitudes. Children with DRD4 7R showed similar performance problems and lower Cue-P3 and CNV, but Nogo-P3 was not reduced. Children with the DAT1 10-6 haplotype had no difficulties with performance or Cue-P3 and CNV, but contrary to expectations increased Nogo-P3. There were no Genotype by ADHD interactions. CONCLUSIONS This study detected specific effects of DRD4 7R on performance and brain activity related to attentional orienting and response preparation, while DAT1 10-6 was associated with elevated brain activity related to inhibitory response control, which potentially compensates increased impulsivity. As these genotype effects were additive to the impact of ADHD, the current results indicate that DRD4 and DAT1 polymorphisms are functionally relevant risk factors for ADHD and presumably other disorders sharing these endophenotypes