referred to as 34 novex 34 fibrin the experimental fibrin containing pellets used in the tests described herein had the following constituents in the amounts listed below ______________________________________experimental pelletsingredient amount mg ______________________________________zeranol 12fibrin 3 35boric acid 0 55magnesium stearate 0 40fd amp c yellow 0065 16 31 total______________________________________ the above ingredients were thoroughly blended and then pelleted using a cylindrical die insert in a model b 2 stokes rotary tableting machine to form cylindrical pellets containing the above ingredients in the above amounts the pellets were approximately 0 090 inches in diameter and 0 13 inches in length the hardness of the pellets was in the range of 5 10 strong cobb hardness units more particularly about 5 78 schu three 12 mg dosage experimental pellets using the 34 novex 34 fibrin excipient of the subject invention were used to implant the right ears of each of the three castrated male angus hereford calves the implant sites were examined by incision sixty five days after the above implants were made the pellets containing 34 novex 34 fibrin excipient had been completely absorbed the fibrin excipient was concluded to be completely biocompatible and gave excellent absorption of the active biochemical agent it was concluded from the above results that the fibrin excipient is readily absorbable and can be used as a suitable excipient for subcutaneous implant pellets to administer active biochemical agents to animals the above results were further verified by a second test eighteen angus charolais calves were used consisting of fourteen castrated male calves and four female calves fifteen of the above calves were implanted in their.