Accuracy of the modified vertebral heart score and the cardio-vertebral ratio for radiographic evaluation of cardiomegaly in ferrets

Thoracic radiography is commonly used to assess the size of the heart and diagnose cardiac disease in ferrets. Several standardized radiographic heart size indicators have been introduced in this species and values in healthy ferrets have been reported. To date, none of these indicators has been tested in ferrets with cardiac disease. The aim of this prospective and retrospective, analytical observational design study was to assess the accuracy of the modified vertebral heart score (mVHS) and the cardio-vertebral ratio (CVR) in the radiographic detection of cardiomegaly in ferrets. Thoracic radiographs of 24 ferrets with confirmed heart diseases, 22 ferrets with non-cardiac diseases and normal-sized hearts on echocardiogram, and 24 healthy ferrets were mixed and examined by three independent and blinded radiologists who measured mVHS and CVR in right lateral (RL) and ventrodorsal (VD) radiographs. For all readers, ferrets with cardiac disease had significantly higher mVHS and CVR than ferrets without cardiac disease on echocardiography. Optimal cut-points for predicting cardiac enlargement were 6.25 vertebrae and 7.25 vertebrae for RL-mVHS and VD-mVHS, and 1.58 and 1.80 for RL-CVR and VD-CVR, respectively. Using these cut-points, the accuracy was good for indicators measured in RL radiographs (92.9% for RL-mVHS; 91.4% for RL-CVR) and moderate for indicators measured in VD radiographs (88.6% for VD-mVHS; 85.7% for VD-CVR). Findings supported the use of mVHS and CVR for evaluating the size of the heart in diseased ferrets, with caution in values interpretation when pericardial fat prevents precise delineation of the cardiac silhouette contour especially on VD radiographs.     

Oral doxycycline pharmacokinetics: Lambs in comparison with sheep

The pharmacokinetics of doxycycline was investigated in lactating sheep and lambs after oral administration at a dose of 10 mg/kg. Concentrations in plasma and milk were assayed with HPLC-PDA analysis. Doxycycline penetrates into the milk, and levels (0.38 ± 0.21 μg/ml) were found 0.5 hr after the treatment. The results suggest that the lambs can be exposed to doxycycline by suckling milk from their treated mothers. Population pharmacokinetic analysis showed a positive relationship between age, which reflects the stage of development of rumen function, and clearance. Possible explanations for the observed differences include the undeveloped rumen in lambs, the differences in the feed and liver function as evidenced by the blood biochemical parameters aspartate aminotransferase (AST) and alanine aminotransferase (ALT), which were significantly lower in lambs (62.67 ± 27.83 U/L and 8.50 ± 6.80 U/L) than in sheep (114.33 ± 20.77 U/L and 18.00 ± 3.16 U/L).     

Effect of vitamin E supplementation on lipid peroxidation in blood and lung of influenza virus infected mice

The influenza virus infection (A/Aichi/2/68) was associated with development of oxidative stress in lung and blood of mice, accompanied by an increase in levels of lipid peroxidation products (conjugated dienes and total malondialdehyde) and a decrease in endogenous amounts of natural antioxidant vitamin E. These effects were most pronounced on the 5th day after virus inoculation, in comparison with those on the 7th. Supplementation of mice with exogenous vitamin E before virus inoculation lead to lung and blood protection against lipid peroxidation. A marked decrease in lipid peroxidation products and an increase in vitamin E content was established in blood and lung on the 5th and 7th day after virus inoculation. The stabilizing effect of vitamin E is dose-dependent in blood and dose-independent in lung, and was most pronounced on the 5th day after virus inoculation in comparison with the 7th day.     

Effects of Neonatal Gonadectomy on Structure of the Bursa of Fabricius in the Chicken A Light Histoquantitative Study

Quantitative stereological study of the bursa of Fabricius in Prelux chickens was performed 3 and 6 months after neonatal gonadectomy. The different structural changes were revealed in bursal follicles, epithelium and stroma of male and female chickens. In orchidectomized animals, the weight of bursa was increased compared to the nonoperated males. Stereological analysis revealed that the absolute amount of bursal follicles was increased due to the increased mass of follicular medulla. The number of areas of follicle-associated epithelium at the bursal mucosa, which in a mature bursa corresponds to the follicle number, was decreased. The height of follicle-associated epithelium (3 months) was decreased and the diameter of the follicle-associated epithelium (6 months) was increased. No changes in the surface density of bursa] epithelium was registered 3 and 6 months after neonatal gonadectomy. In ovariectomized chickens the weight of bursa was decreased in comparison to the nonoperated females. Histoquantitative analysis showed that the bursal follicular mass was decreased due to the decreased absolute amount of follicular medulla (3 and 6 months) and cortex (6 months), whereas the number and diameter of follicles were not changed. The height of interfollicular and follicle-associated epithelium was decreased, but no changes in the surface density of bursal epithelium was registered. Relative proportion of bursal stroma was increased. The studies presented further support of the concept that the functional relation between gonads and bursa of Fabricii exists during the postnatal period in the chicken.