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G.F. Gee

Publications and source records attributed to G.F. Gee.

56 records · Page 4Linked to original sources

A comparative study on the cryogenic preservation of semen from the sandhill crane and the domestic fowl

SYNOPSIS: Recent findings on the cryogenic preservation of semen from the crane, Grus canadensis pratensis and the domestic fowl, Gallus domesticus, are compared. Highest levels of post-thaw motility for crane semen (55%) were obtained when semen was diluted 1:1 with the Beltsville Poultry Semen Extender (BPSE) and held for 30 min at 5 C before it was equilibrated with 4% dimethyl sulfoxide (DMSO) for 15 min. In contrast, post-thaw motility for fowl spermatozoa was highest (80%) when semen was diluted 1:3 with BPSE and held for 60 min at 5 C before it was equilibrated with 4% DMSO for 60 min. Post-thaw motility of spermatozoa of both species was highest when the following freezing rates were used: l C per min from +5 to -20 C, 50 C per min from -20 to -80 C, then plunging into liquid nitrogen which resulted in a rate of 160 C per min from -80 to -196 C. One of four crane eggs resulting from insemination with frozen-thawed semen was fertile, whereas 27 of 55 fowl eggs were fertile, but this difference may have been due largely to fewer spermatozoa being inseminated into the female crane than into the fowl.

Book chapter

Artificial insemination for breeding non-domestic birds

Captive breeding of non-domestic birds has increased dramatically in this century, and production of young often exceeds that of the same number of birds in their native habitat. However, when infertility is a problem, artificial insemination can be a useful method to improve production. Artificial insemination programs with non-domestic birds are relatively recent, but several notable successes have been documented, especially with cranes and raptors. Three methods of artificial insemination are described--cooperative, massage, and electroejaculation. Cooperative artificial insemination requires training of birds imprinted on man and is used extensively in some raptor programs. The massage technique generally is used when there are larger numbers of birds to inseminate since it requires less training of the birds than with the cooperative method, and a larger number of attempted semen collections are successful. Although the best samples are obtained from birds conditioned to capture and handling procedures associated with the massage method, samples can be obtained from wild birds. Semen collection and insemination for the crane serves to illustrate some of the modifications necessary to compensate for anatomical variations. Collection of semen by electrical stimulation is not commonly used in birds. Unlike the other two methods which require behavioral cooperation by the bird, electroejaculation is possible in reproductively active birds without prior conditioning when properly restrained. Fertility from artificial insemination in captive non-domestic-birds has been good. Although some spermatozoal morphology has been reported, most aspects of morphology are not useful in predicting fertility. However, spermatozoal head length in the crane may have a positive correlation with fertility. Nevertheless, insemination with the largest number of live spermatozoa is still the best guarantee of fertile egg production.

Book chapter