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A simple and inexpensive pipette for in vivo recovery of sheep oocytes by folliculocentesis was developed. Two experiments were conducted to assess the recovery rate. In Experiment 1, 20 Merino × Corriedale ewes were heat synchronized using intravaginal sponges containing 60 mg of medroxyprogesterone acetate (MPA) for a period of 12 days. In Experiment 2, 26 Merino × Corriedale ewes were synchronized with CIDR® devices for 12 days, with the original device being replaced by a new one on Day 10 (2 days before withdrawal). In both experiments, ewes were superovulated with a total dose of 16 mg of follicle stimulating hormone (FSH) given in six decreasing dosage injections, starting 48 h before sponge/CIDR removal. Folliculocentesis was performed 36–40 h after sponge removal, and 16–20 h after CIDR removal. Overall, an average of 12.5 follicles per ewe were punctured and 10.2 oocytes per ewe were recovered (recovery rate 81.9%). The differences between the two experiments in terms of follicles punctured per ewe (10.8 vs. 13.7) and oocytes recovered per ewe (8.5 vs. 11.5) were not statistically significant ( P >0.05). The follicle size did not significantly ( P >0.05) affect the recovery rate, although there was a tendency for higher rates of recovery from 1–5 mm follicles (88.5%) compared with follicles over 5 mm (79.5%).

We describe a technique for mechanical cardiac assistance in an acute model of severe cardiac failure. Cardiac dysfunction was induced by a high dose of halothane in 13 dogs. Seven served as controls. Following median sternotomy, a pneumatically driven device was implanted in the other six dogs in a para-aortic position, using a simple surgical technique without cardiopulmonary bypass. The aorta was cross-clamped during cardiac assistance. During hemodynamic studies, the seven control animals with induced cardiac failure showed high end-diastolic left ventricular and right atrial pressures with low cardiac index and systolic left ventricular and aortic pressures. All dogs in this group died within 30 minutes. Use of a monovalvular cardiac assist device in the experimental group of six dogs to pump blood from the aortic root to the descending aorta in a counterpulsation manner, confirmed good preservation of systemic hemodynamic parameters after induction of heart failure. All animals in this treated group survived more than 45 minutes. Hemodynamically, the device acts as a new ventricle and the impaired left ventricle functionally becomes a left atrium. This condition is clinically appropriate for recovery of left ventricular function in severe acute myocardial failure.