Section 522.2012 - Prostalene(a)Specifications. Each milliliter of solution contains 1 milligram of prostalene.(b)Sponsor. No. 054771 in § 510.600(c) of this chapter.(c)Conditions of use in horses - (1)Amount. Administer 5 micrograms per kilogram of body weight as a single subcutaneous injection.(2)Indications for use. For the control of estrus in mares.(3)Limitations. Do not use in horses intended for human consumption. Federal law restricts this drug to use by or on the order of a licensed veterinarian. 79 FR 16195 , Mar. 25, 2014