Analysis of right ventricular areas to assess the severity of ascites syndrome in broiler chickens

Ascites syndrome in broiler chickens is defined as a condition associated w ith pulmonary hypertension leading to right heart failure, increased centra l venous pressure, passive congestion of the Liver, and accumulations of se rous fluids in body cavities. The syndrome is currently seen in fast-growin g broiler chickens associated with an increase in the weight, volume, and a rea of the right ventricle of the heart. The ratio of the right ventricle w eight to the total heart mass has been used to assess the consequences of i ncreased blood pressure. The right ventricle area (RVA) can be quantified u sing image analysis technology. Hearts were removed from 719 male broilers at slaughter (42 d). All birds were visually scored for the incidence of as cites. A score of 0 or 1 represented slight hydropericardium, slight right heart hypertrophy, and slight edema. A score of 4 was assigned to birds wit h marked accumulation of ascitic fluid in one or more ceolomic cavities, pr onounced dilation of the right heart, and prominent liver lesions. A cross-sectional image of each heart slice (a 4-mm-thick slice of the vent ricles) was digitally recorded. Using image analysis software, the RVA, lef t ventricular area (LVA), and total heart area (HA) were determined. Becaus e a slice of the heart was used in image analysis, the importance of mainta ining the original shape was determined. Twenty hearts in five ranges of RV A size were scanned in four different positions, which have differing heart slice orientations and differing RVA shapes, for a comparison of positioni ng technique (placement) relating to the RVA. The shape of the heart slice for image analysis was observed not to be critical for the small RVA. For h eart slices with large RVA values, it was found to be critical to analyze t he heart slice in a standardized placement.