ULTRASONOGRAPHY AS A TOOL FOR MONITORING INOVO CHICKEN DEVELOPMENT .2. EFFECTS OF EGGSHELL ALTERATION AND ULTRASONOGRAPHY ON EMBRYONIC AND POSTHATCH DEVELOPMENT

The influence of creating and closing acoustic windows on embryonic an d posthatch development for the purpose of chicken embryogenesis monit oring by real-time ultrasonography (US) was evaluated at 2, 6, 9, 14, and 17 days of incubation. Acoustic windows were closed using either a porous dialysis film and tape (FM) or an eggshell allograft attached with collodion (CP). Results from eggs closed in each manner with and without concurrent nonsterile US examination. were compared with two c ontrol groups. Window creation reduced hatchability. The hatchability reduction was groups primarily by bacterial contamination. Contaminati on was more common in the FM eggs than in the CP eggs and was greater in eggs that also underwent US. Hatchability increased and contaminati on decreased when US was performed closer to hatch. Egg weight loss wa s increased after Day 6 of incubation in FM + US eggs treated on Day 2 and after Day 9 in all eggs with windows except CP eggs treated on Da y 9 and CP + US eggs treated on Days 6 and 9. Hatch weight decreased i n chicks from eggs that had windows, particular in FM eggs.