This unusual all-plastic trocar can be used for emergency bloat. The 10mm bore ensures quick relief of pressure. The whole trocar is punched through the hide, as for usual emergency treatment, and then screwed down until the cannula top is flush on the hide. The trocar is then pulled out allowing the rumen gas and foam to escape. The benefit of this device is that the cannula thread maintains alignment of the rumen against the peritoneum, reducing internal contamination and associated trauma.