14 Dec An injection of prostaglandin causes the CL to regress earlier than normal. This eliminates the source of progesterone. Usually, in two to five days after receiving prostaglandin, the female comes into heat and is ready for breeding. In order for the prostaglandin to destroy the CL and speed up the estrous. 25 Jan The IBR fraction of the vaccine has been shown to cause swelling of the ovaries, which could interfere with cyclicity; they wouldn't be able to become pregnant until after that problem resolves. Even cows can have this problem, so we recommend giving these vaccines at least a month before breeding,” he. Read Tara's Breeding - Part 1 from the story One shots by everythingiscool with reads. oneshot, fxf, mxf. Warning: force Tara Bridges opened the do.