Possible Commercial Method of Freezing Chicken Semen

Introduction Primary breeders are currently faced with the same problem plaguing most animal industries, rising production costs. Labor, feed and energy costs are forcing primary breeders to consider more economical ways of maintaining gene pools. One way to reduce such costs is with the use of frozen semen. With frozen semen available from superior sires, primary breeders will have the tool to (a) increase genetic advancement per generation,' (b) gain a more precise evaluation of genetic improvement, (c) allow more efficient use of sires, and (d) distribute genetic material worldwide. Further benefits from needing fewer breeder males and obtaining better quality offspring from the use of superior sires will more than pay for the cost of a semen preservation program. Interest in the preservation of chicken semen began in 1941 when Shaffner, working at the University of Maryland, obtained progeny from hens inseminated with frozen Semen. From 1948 until the late 1960's considerable reserach was devoted to the problem of preserving poultry semen. This work was reviewed by Lorenz in 1969 and later by Lake (1978). The purpose of this paper is to discuss a commercial method of freezing chicken semen, henceforth referred to as the Beltsville method, and discuss those factors which most influence the fertility of frozen semen.