A total of 24 puppies (average body weight, 3.7kg) were subjected experimentally to surface-cooling, simple hypothermia using a ventilator with a respiratory rate of 25/min. and a tidal volume of 25ml/kg, 20ml/kg, and 15ml/kg, when the esophageal temperature was 30°C. During the circulatory arrest (about 30 minutes), the chordae tendineae was experimentally ruptured and mitral vulvuloplasty was performed. From the results of PaCO₂ measurements during circulatory arrests, puppies were divided into 3 groups: group I (PaCO₂ 10—20 mmHg), group II (PaCO₂ 20—30 mmHg), and group III (PaCO₂ 30-40 mmHg) . Group I demonstrated better result than group II or III in term of the resuscitation of the heart. The pH just before circulation arrest in group I averaged 7.529 (measured at 37°C), and its corrected value at 24°C was 7.724. The tidal volume was 25ml/kg, and the duration of the ventilation was about 40 minutes.

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The effects of xylazine on gastrointestinal motility in conscious goats and dogs were studied by using strain gauge force transducers and bipolar electrodes. Vomiting induced by xylazine in the dog was also observed under feeding, drugs injections or vagotomy.
1) Continuous activity and no activity for a short period in the abomasum, and migrating myoelectric complex (MMC) in the small intestine were observed cyclically in the goat.
2) Digestive and interdigestive contractions in the gastrointestine were observed in the dog.
3) Contractile and electrical activity continued in the antrum of the goat after xylazine injection but were restricted in other parts of the antrum.
4) Vomiting induced by xylazine was observed in the dog with full stomach more than that with empty one. The reflex of vomiting were not inhibited completely by pretreatments of atropine and propionylpromazine, though phentoramine and yohimbine inhibited the phenomenon.
5) Antiperistaltic contractile and electrical activity from the lower part of the small intestine in the dog were observed before vomiting, and dysrhythmia of the basic electrical rhythm (BER) was also observed before and after vomiting following xylazine injection.
The results indicated that the affecting site of xylazine is the central nervous system (CNS) and that its actions are revealed by excitation of a2-adrenoceptor. Furthermore, the results suggested that the impulse to vomit is transmitted not only to the vagus but also outside the vagus.

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GOF anesthesia in closed system was performed on 5 cattle weighing 23 to 453 kg. The results obtained in this study were summerized as follows.
1. In premedication, injection of 0.05mg/kg atropin sulfate reduced secretions effectively from the respiratory tract and salivary glands and of 1mg/kg chlorpromazine-HCL produced good sedation.
2. In induction anesthesia, mixed intravenous administration of 5% guaiacol glycerol ether (100 mg/kg) and thiamylal-Na (5mg/ kg) also produced a suitable narcosis for easy intubation.
3. Utilizing the oxygen monitor for detection of O₂ concentration in inhalation gas, nitrous oxide gas was not only able to use in safety in closed anesthesia system, but brought a suitable influence to reduce the amount of halothane.

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