Computed tomography (CT) scan findings in calves with hydranencephaly.

BACKGROUND: Hydranencephaly is the unilateral or bilateral loss of cerebral hemispheres and their replacement by a cerebrospinal fluid-filled sac that is caused by some teratogenic viruses. This disorder can be recognized before death occurs, using computed tomography (CT) scan. Pathological findings are also useful for the confirmation of the diagnosis. AIMS: The aim of this study was to determine features of hydranencephaly in calves by CT. METHODS: In this study, CT images were obtained from the skulls of 7 same-age calves with neurological signs, affected by Akabane virus, after slaughter. To compare the Hounsfield unit (HU) obtained from each brain region with the normal one, a normal calf's (with the same age) CT images were considered. Then, HU was measured in different parts of the affected calves' brain and compared with the normal calf's brain. RESULTS: Computed tomography images of affected calves indicated a hypoattenuated density of cerebral hemispheres, and the mean value of HU significantly decreased in these parts of the brain compared to normal calves (P=0.0001). There was no statistically significant difference between the mean value of the brain stem HU of the affected calves and the normal ones (P=0.066). In the gross pathology, asymmetric fluid-filled sacs that replaced cerebral hemispheres were observed, but the brain stems were intact in all cases. CONCLUSION: The results showed a strong correlation between CT scan and pathology findings in calves with hydranencephaly. This is the first CT scan-mediated study of calves with hydranencephaly.

Pulsed wave Doppler echocardiographic assessment after sedation by intravenous injection of medetomidine and xylazine hydrochloride on cardiac output and systolic time intervals in one-humped camel calves (Camelus dromedarious).

BACKGROUND: Pulsed wave (PW) Doppler echocardiography provides a convenient and noninvasive tool for measuring cardiac output (CO) alternations after the administration of sedative drugs, but this is not a usual method for camelids. AIMS: The aim of the present study was to investigate the changes of the left and right ventricular outflow tracts (LVOT and RVOT), CO, and systolic time intervals following the intravenous (IV) injection of medetomidine (M) and xylazine (X) using PW Doppler echocardiography. METHODS: Twenty apparently healthy immature male one-humped camels (Camelus dromedarious) were selected and divided into four groups (five animals per group). Medetomidine and X were injected to the left jugular vein at two different doses of 10 and 20 µg/kg, and 0.2 and 0.4 mg/kg, respectively. Effects on echocardiographic parameters were assessed at 4 intervals: before, 3, 60, and 120 min after drug administrations. RESULTS: Velocity time integrity (VTI), maximum/mean flow velocity (Vmax and Vmean) and maximum/mean pressure gradient (PGmax and PGmean) decreased in aortic and pulmonic valves. Left ventricular ejection time (LVET) and LVET + pre ejection period (PEP) decreased and PEP and PEP/LVET increased in all groups except the low dose X group, 3 min after drug administration (P<0.05). The least values of VTI, velocity (V), PG and CO were observed after 60 min in the low dose X group (P<0.05). CONCLUSION: A relationship was found between the intensity and the duration of changes in cardiac parameters and both types and dosages of the injected drugs. We concluded that X and M have transient depressor effects on the ventricular outflow tract and CO of healthy camels.