[Risks of intravenous injection into the tail of cattle]

Since several years collecting blood from the tail vessels in bovine practice gained a wider range of propagation. Recently veterinarians tried to inject drugs intravenously into the tail vessels of the bovine tail. Therefore we carried out anatomical studies concerning the position of the blood vessels of the bovine tail. 24 tails of slaughtered cattle, which were of different breeds and age (1-4 years old), were examined in respect to the course of their arteries and veins as well on the ventral side. By means of necropsy, frozen cross sections, corrosion anatomy and radiography the position of the tail vessels to each other were compared. In the area of the 2nd to 7th coccygeal vertebra the position of the arteries and veins were being determined. Following results were obtained: 1. The A. cocc. med. runs always ventral in the midline of the tail. 2. The number of ventral veins proximal on the tail varies from 1 to 3. 3. The course of the Vena(ae) cocc. mediana(ae) in the tail region examined is inconstant. The vein lies either left, right, dorsal or ventral of the A. cocc. med. The vein can also cross the area. 4. In 8 of 19 examined cases the V. cocc. med. was closely left to the artery (area of the 5th coccygeal vertebra). After radiologic examination it can be stated that this region can be used for collecting blood of the V. cocc. med. In case of intravenous application of considerable amounts of drugs into the vein of the tail a certain portion can get easily into the closely attached artery and severe complications, as necrosis of the tail can occur. Therefore our clinic recommends generally the use of the Vena jugularis externa for intravenous injection.