490 



BOAED OF AGRICULTURE. [Pub. Doc. 



that the operator may easily grasp it and attach the syringe. In 

 this way from ninety to one hundred head of yearling calves may 

 be vaccinated in one hour, with ten men to handle the animals and 

 one assistant to insert the needle ; but such a rate can only be 

 maintained for a limited time without changing the men. With 

 one set of men not more than four hundred or five hundred head 

 should be vaccinated in one day, according to the age and size of 

 the animals. 



On many large ranches, where vaccination for blackleg is prac- 

 tised as regularly as branding, special vaccinating chutes (see fig. 3) 

 have been constructed, which in principle resemble the ordinary 

 squeezer, or branding chute. One side of the chute is hinged to 

 the base, and may, by means of a block and tackle, be pulled over 

 against the opposite side, thus squeezing the calves and preventing 

 them from struggling while the needle is inserted and the vaccine 

 injected. One of the planks in the movable side, at a proper 



Fig. 3. — A Vaccinating Chute 



a^fSggg 



distance from the ground, is loose, and hinged to the plank below 

 it, so that it may be opened and give the operator access to the 

 side of the animals. The chute may be built as long or as short 

 as desired, or may be made portable, and carried to any pasture 

 on the ranch and connected with the stationary chutes and pens. 

 Such a chute enables three or four men to vaccinate the same 

 number of calves as ten to twelve men can vaccinate in the same 

 length of time when every animal has to be lassoed or thrown. 



Syno]isis of Vaccination Process. 



(1) Sterilize outfit by boiling. 



(2) Place the contents of one packet in the mortar, and add a 

 few drops of water. 



(3) Work the mixture well with the pestle. 



(4) Add two to five syringes full of water, according to the size 

 of the packet, and stir well. 



