Page Banner

United States Department of Agriculture

Agricultural Research Service

Phil H Purdy
Plant And Animal Genetic Resources Preservation Research Unit
Physiologist (Animals)

Phone: (970) 495-3258
Fax: (970) 221-1427
1111 SOUTH MASON STREET
NCGRP
1111 SOUTH MASON STREET
FORT COLLINS, CO, 80521

Projects
National Animal Germplasm Program
Appropriated (D)
  Accession Number: 423549
Development of a Non-Surgical Sheep Artificial Insemination Technique Utilizing Frozen-Thawed Semen
Nonfunded Cooperative Agreement (N)
  Accession Number: 424372
Development of a non-Surgical Artificial Insemination Technique for Use with Sheep and Frozen-Thawed Ram Semen
Nonfunded Cooperative Agreement (N)
  Accession Number: 425638
Development of a Non-Surgical Sheep Artificial Insemination Technique Utilizing Frozen-Thawed Semen
Nonfunded Cooperative Agreement (N)
  Accession Number: 425660
Development of a Sheep Artificial Insemination Procedure Utilizing Frozen-Thawed Semen and a Non-Surgical Insemination Technique
Nonfunded Cooperative Agreement (N)
  Accession Number: 425661

Publications (Clicking on the reprint icon Reprint Icon will take you to the publication reprint.)
A preliminary report on the impact of cryopreservation diluent on ram sperm physiology and cervical artificial insemination - (Proceedings)
Purdy, P.H., Spiller, S.F., Rice, S.D., Koeoke, K.L., Mcguire, E.M., Mcguire, K.E., Stobart, S., Blackburn, H.D. 2014. A preliminary report on the impact of cryopreservation diluent on ram sperm physiology and cervical artificial insemination. Symposium Proceedings. Western Section American Society of Animal Science, June 25-27, 2014, San Angelo, Texas.
Editor, Sheep Production Handbook, Chapter entitled ‘Reproduction’ - (Book / Chapter) - (17-Jun-14)
Membrane modification strategies for cryopreservation. pp xx-xx. In: Willem F. Wolkers and Harriette Oldenhof (eds.). Methods in cryopreservation and freeze-drying. The lab protocol series Methods in Molecular Biology. - (Book / Chapter) - (21-May-14)
Fertility prediction of frozen boar sperm using novel and conventional analyses - (Abstract Only)
Daigneault, B.W., Mcnamara, K.A., Purdy, P.H., Rodriguez_Zas, S.L., Krisher, R.L., Knox, R.V., Miller, D.J. 2014. Fertility prediction of frozen boar sperm using novel and conventional analyses. Meeting Abstract. Society for the Study of Reproduction, Grand Rapids, MI, July 19-23, 2014.
Novel and traditional traits of frozen-thawed porcine sperm related to in vitro fertilization success - (Peer Reviewed Journal)
Daigneault, B.W., Mcnamara, K.A., Purdy, P.H., Krisher, R.L., Knox, R.V., Miller, D.J. 2014. Novel and traditional traits of frozen-thawed porcine sperm related to in vitro fertilization success. Theriogenology. 82:266-273.
Post-thaw motility of frozen boar sperm does not predict success with in vitro fertilization - (Abstract Only)
Daigneault, B.W., Mcnamara, K.A., Purdy, P.H., Knox, R.V., Krisher, R.L., Miller, D.J. 2013. Post-thaw motility of frozen boar sperm does not predict success with in vitro fertilization. Meeting Abstract. Society for the Study of Reproduction, Montreal, Quebec, Canada, July 22-26, 2013.
Effect of storage time on the viability of cryopreserved bovine spermatozoa - (Abstract Only)
Gallegos, A.I., Ericsson, S.A., Blackburn, H.D., Spiller, S.F., Warnock, B.J., Meador, M.K., Smith, M.W., Purdy, P.H. 2013. Effect of storage time on the viability of cryopreserved bovine spermatozoa. Meeting Abstract. American Society of Animal Science, Indianapolis, IN, July 8-12, 2013.
Current biotechnologies and future possibilities in preservation of animal germplasm - (Abstract Only) - (28-Jun-13)
A simple vitrification method for cryobanking avian testicular tissue - (Peer Reviewed Journal)
Liu, J., Cheng, K.M., Purdy, P.H., Silversides, F.G. 2012. A simple vitrification method for cryobanking avian testicular tissue. Poultry Science. 91:3209-3213.
Effects of alternative cryoprotectants, diluents, straw size and cholesterol addition on cryopreserved rooster sperm - (Abstract Only)
Tarvis, K.M., Purdy, P.H., Graham, J.K. 2012. Effects of alternative cryoprotectants, diluents, straw size and cholesterol addition on cryopreserved rooster sperm. Meeting Abstract. International Congress on Animal Reproduction, Vancouver, BC, Canada, July 29-August 2, 2012.
185 Cost Effectiveness of Maintaining Research Chicken Populations in Situ Or with Cryopreserved Semen Or Ovaries - (Abstract Only)
Silversides, F.G., Purdy, P.H., Blackburn, H.D. 2012. 185 Cost effectiveness of maintaining research chicken populations in situ or with cryopreserved semen or ovaries. Meeting Abstract. Poultry Science Association, Athens, GA, July 9-12.
Comparative costs of programmes to conserve chicken genetic variation based on maintaining living populations or storing cryopreserved material - (Peer Reviewed Journal)
Silversides, F., Purdy, P.H., Blackburn, H.D. 2013. Comparative costs of programmes to conserve chicken genetic variation based on maintaining living populations or storing cryopreserved material. British Poultry Science. 53:599-607.
Boar sperm quality in lines of pigs selected for either ovulation rate or uterine capacity - (Peer Reviewed Journal)
Freking, B.A., Purdy, P.H., Spiller, S.F., Welsh, C.S., Blackburn, H.D. 2012. Boar sperm quality in lines of pigs selected for either ovulation rate or uterine capacity. Journal of Animal Science. 90(8):2515-2523.
Changing rooster sperm membranes to facilitate cryopreservation - (Abstract Only)
Graham, J.K., Travis, K.M., Purdy, P.H. 2012. Changing rooster sperm membranes to facilitate cryopreservation. Meeting Abstract. International Embryo Transfer Society, Phoenix, AZ. January 10, 2012.
Cryoconservation of animal genetic resources. Animal Production and Health Guidelines No. 12 - (Book / Chapter)
Blackburn, H.D., Godke, R., Purdy, P.H., Hiemstra, S., Woelders, H., Mariante, A., Pizzi, F., Boettcher, P. 2012. Cryoconservation of animal genetic resources. Animal Production and Health Guidelines No. 12. Complete Book. FAO, Rome p. 222.
Genetic Structure and Diversity among U.S. sheep breeds: Identification of the major gene pools. - (Peer Reviewed Journal)
Blackburn, H.D., Paiva, S.R., Wildeus, S., Getz, W., Stobart, R., Bixby, D., Purdy, P.H., Welsh, C.S., Spiller, S.F., Brown, M.A. 2011. Genetic Structure and Diversity among U.S. sheep breeds: Identification of the major gene pools. Journal of Animal Science. 89:2336-2348.
Sperm quality assessment in mammals by flow cytometry In: T.R. Tiersch and C.C. Green (eds.) Cryopreservation in Aquatic Species, 2nd Edition. World Aquaculture Society, Baton Rouge, LA. - (Book / Chapter)
Purdy, P.H. 2011. Sperm quality assessment in mammals by flow cytometry pp. 219-226. In: T.R. Tiersch and C.C. Green (eds.) Cryopreservation in Aquatic Species, 2nd Edition. World Aquaculture Society, Baton Rouge, LA.
Effect of number of motile frozen-thawed boar sperm and number of fixed-time inseminations on fertility in estrous-synchronized gilts - (Peer Reviewed Journal)
Spencer, K.W., Purdy, P.H., Blackburn, H.D., Spiller, S.F., Stewart, T.S., Knox, R.V. 2010. Effect of number of motile frozen-thawed boar sperm and number of fixed-time inseminations on fertility in estrous-synchronized gilts. Animal Reproduction Sciences. 121:259-266.
Reproductive biotechnologies and management of animal genetic resources - (Proceedings)
Blackburn, H.D., Purdy, P.H. 2010. Reproductive biotechnologies and management of animal genetic resources. XIIIth European Poultry Conference, Tours France, August 23-27, 2010. Meeting Proceedings.
Implications of the pH and temperature of diluted, cooled boar semen on fresh and frozen-thawed sperm motility characteristics - (Peer Reviewed Journal)
Purdy, P.H., Tharp, N., Stewart, T., Spiller, S.F., Blackburn, H.D. 2010. Implications of the pH and temperature of diluted, cooled boar semen on fresh and frozen-thawed sperm motility characteristics. Theriogenology. 74:1304-1310.
Evaluation of Glycerol Removal Techniques, Cryoprotectants, and Insemination Methods for Cryopreserving Rooster Sperm with Implications for Breed and/or Line Regeneration - (Peer Reviewed Journal)
Purdy, P.H., Song, Y., Silversides, F.G., Blackburn, H.D. 2009. Evaluation of Glycerol Removal Techniques, Cryoprotectants, and Insemination Methods for Cryopreserving Rooster Sperm with Implications for Breed and/or Line Regeneration. Poultry Science. 88:2184-2191
Inseminating fresh or cryopreserved semen for maximum efficiency: implications for gene banks and industry - (Peer Reviewed Journal)
Blackburn, H.D., Silversides, F., Purdy, P.H. 2009. Inseminating fresh or cryopreserved semen for maximum efficiency: implications for gene banks and industry. Poultry Science. 88:2192-2198.
The fertility of ram sperm held for 24 hours at 5 ºC prior to cryopreservation - (Peer Reviewed Journal)
Purdy, P.H., Moce, E., Stobart, R., Murdoch, W.J., Moss, G.E., Larson, B., Ramsey, S., Graham, J.K., Blackburn, H.D. 2009. The fertility of ram sperm held for 24 hours at 5 ºC prior to cryopreservation. Animal Reproduction Sciences. 118:231-235.
Treating ram sperm with cholesterol-loaded cyclodextrins improves cryosurvival - (Peer Reviewed Journal)
Moce, E., Purdy, P.H., Graham, J.K. 2009. Treating ram sperm with cholesterol-loaded cyclodextrins improves cryosurvival. Animal Reproduction Sciences. 118:236-247.
Conservation of Swine Genetics by the National Animal Germplasm Program (NAGP) after One Decade Reprint Icon - (Popular Publication)
Blackburn, H.D., Stewart, T., Purdy, P.H. 2009. Conservation of Swine Genetics by the National Animal Germplasm Program (NAGP) after One Decade. National Hog Farmer.
Investigation of a novel non-surgical method of artificial insemination for sheep - (Proceedings)
PPurdy, P.H., Blackburn, H.D., Larson, B., Stobart, R. 2009. Investigation of a novel non-surgical method of artificial insemination for sheep. Western section of Amercan Society of animal Science, Fort Collins, CO, June 16-18, 2009.
Influence of pre-cryopreservation pH and temperature on boar semen quality - (Abstract Only)
Tharp, N.E., Purdy, P.H., Blackburn, H.D., Spiller, S.F., Stewart, T. 2009. Influence of pre-cryopreservation pH and temperature on boar semen quality. Midwest Section American Society of Animal Science, Des Moines, IA, March 16-18, 2008.
Evaluation of new techniques to enhance the use of A.I. on farm. - (Abstract Only)
PPurdy, P.H., Stobart, R.H., Larson, B., Blackburn, H.D. 2009. Evaluation of new techniques to enhance the use of A.I. on farm. American Sheep Industry Association Annual Conference, San Diego, CA, January 21-24, 2009.
Effect of number of motile sperm and number of inseminations using frozen boar semen on fertility in gilts - (Trade Journal)
Spencer, K., Purdy, P.H., Blackburn, H.D., Spiller, S.F., Welsh, C.S., Stewart, T., Breen, S., Taibl, J., Yantis, B., Knox, R. 2008. Effect of number of motile sperm and number of inseminations using frozen boar semen on fertility in gilts. National Hog Farmer. http://nationalhogfarmer.com/genetics-reproduction/artificial-insemination/1215-boar-semen-use/.
Perspectives on cryopreservation, quality control, and artificial insemination of frozen-thawed boar sperm in a national repository - (Proceedings)
Purdy, P.H., Knox, R., Singleton, W., Spencer, K., Spiller, S.F., Stewart, T., Tharp, N., Welsh, C.S., Blackburn, H.D. 2008. Perspectives on cryopreservation, quality control, and artificial insemination of frozen-thawed boar sperm in a national repository. Symposium Proceedings. Midwest Boar Stud Managers Conference, Saint Louis, MO August 7-8, 2008.
Ubiquitination and its influence in boar sperm physiology and cryopreservation Reprint Icon - (Peer Reviewed Journal)
Purdy, P.H. 2008. Ubiquitination and its influence in boar sperm physiology and cryopreservation. Theriogenology 70:818-826.
Swine gene banking: A quality control perspective on collection, and analysis of samples for a national repository Reprint Icon - (Peer Reviewed Journal)
Purdy, P.H. 2008. Gene banking: A quality control perspective on collection, and analysis of samples for a national repository. Theriogenology. 10.1016/j.theriogenology.2008.06.012
Boar fertility and semen quality characteristics in lines of pigs selected for component traits of female reproduction Reprint Icon - (Abstract Only)
Freking, B.A., Purdy, P.H., Welsh, C.S., Spiller, S.F., Blackburn, H.D. 2008. Boar fertility and semen quality characteristics in lines of pigs selected for component traits of female reproduction [abstract]. Journal of Animal Science Supplement. 86(E-Suppl. 2):208-209. Abstract #W50.
Detection of boar sperm plasma membrane protein using Rhodamine 640; implications for cryobiology and physiology - (Abstract Only)
Purdy, P.H. 2008. Detection of boar sperm plasma membrane protein using Rhodamine 640; implications for cryobiology and physiology. American Society of Andrology Meeting, Albuquerque, New Mexico, April 2008. Pp. 49.
Gene banking: A quality control perspective on collection, and analysis of samples for a national repository - (Abstract Only)
Purdy, P.H. 2007. Gene banking: A quality control perspective on collection, and analysis of samples for a national repository. Theriogenology. 6th International Conference on Boar Semen Preservation, Alliston, Ontario, Canada, August 11-15, 2007.
Semen cryopreservation research seeks higher fertility rates in rainbow trout - (Popular Publication)
Silverstein, J.T., Purdy, P.H., Blackburn, H.D. 2007. Semen cryopreservation research seeks higher fertility rates in rainbow trout. Global Aquaculture Advocate. 10(2):84.
Preserving Ram Semen: New Science Shows it can be Stored for up to Two Days Before Freezing - (Popular Publication)
Purdy, P.H. 2007. Preserving Ram Semen: New Science Shows it can be Stored for up to Two Days Before Freezing. Sheep! Magazine. p.40-41.
Relationship of flow cytometric evaluations of cryopreserved rainbow trout Oncorhynchus mykiss sperm with fertility - (Abstract Only)
Purdy, P.H., Blackburn, H.D., Silverstein, J. 2007. Relationship of flow cytometric evaluations of cryopreserved rainbow trout Oncorhynchus mykiss sperm with fertility. Aquaculture 2007 Annual Meeting. p 734.
A Method for Cryopreserving Chicken Primordial Germ Cells - (Peer Reviewed Journal)
Moore, D.T., Purdy, P.H., Blackburn, H.D. 2006. A Method for Cryopreserving Chicken Primordial Germ Cells. Poultry Science. 85:1784–1790.
Ubiquitination of Boar Sperm: What Does This Reveal About Sperm Physiology? - (Abstract Only)
Purdy, P.H. 2006. Ubiquitination of boar sperm: what does this reveal about sperm physiology? Annual Meeting of the Society for the Study of Reproduction, Omaha, NE, July 29-August 1, 2006. p.189.
Variation in Sperm Cell Quality in Cryopreserved Boar Semen - (Peer Reviewed Journal)
Stewart, T., Gunsett, F., Welsh, C.S., Spiller, S.F., Purdy, P.H., Blackburn, H.D. 2006. Variation in sperm cell quality in cryopreserved boar semen. 8th World Congress of Genetics Applied in Livestock Production. 11(23):1-4.
The Post-Thaw Quality of Ram Sperm Held for 0 to 48 Hours at 5°c Prior to Cryopreservation - (Peer Reviewed Journal)
Purdy, P.H. 2006. The post-thaw quality of ram sperm held for 0 to 48 hours at 5°c prior to cryopreservation. Animal Reproduction Sciences. 93:114-123.
The Fluidity of Chinese Hamster Ovary Cell and Bull Sperm Membranes after Cholesterol Addition - (Peer Reviewed Journal)
Purdy, P.H., Fox, M.H., Graham, J.K. 2005. The fluidity of chinese hamster ovary cell and bull sperm membranes after cholesterol addition. Cryobiology. 51:102-112.
Cholesterol-Loaded Cyclodextrin Improves Post-Thaw Goat Sperm Motility - (Abstract Only)
Barrera-Compean, M.H., Purdy, P.H., Dzakuma, J.M., Newton, G.R., Nuti, L.C. 2005. Cholesterol-loaded cyclodextrin improves post-thaw goat sperm motility. Journal of Animal Science. 2005. 83 (Supl 1):153.
A Review on Goat Sperm Cryopreservation - (Peer Reviewed Journal)
Purdy, P.H. 2006. A review on goat sperm cryopreservation. Small Ruminant Research. 63:215-225.
A Review on Goat Sperm Cryopreservation - (Peer Reviewed Journal)
Purdy, P.H. 2005. A review on goat sperm cryopreservation. Small Ruminant Research.
Effects of Holding Time Prior to Freezing on the Motility, Viability and Membrane Binding Ability of Ram Sperm - (Abstract Only)
Purdy, P.H. 2004. Effects of holding time prior to freezing on the motility, viability and membrane binding ability of ram sperm. 2004 Joint Annual Meeting of the American Dairy Science Association, American Society of Animal Science and Poultry Science Association, July 26-28, 2004, St. Louis, Missouri. Journal of Animal Science. 82(Suppl 1):367.
Effect of Adding Cholesterol to Bull Sperm Membranes on Sperm Capacitation, the Acrosome Reaction, and Fertility - (Peer Reviewed Journal)
Purdy, P.H., Graham, J.K. 2004. Effect of adding cholesterol to bull sperm membranes on sperm capacitation, the acrosome reaction, and fertility. Biology of Reproduction. 71:522-527.
Spanish Buck Ss-B Inhibin/activin (Inhbb) Microsatellite Polymorphisms - (Abstract Only)
Realivasquez, R., Ericsson, S.A., Spiller, S.F., Campbell, W.T., Sternes, K.L., Purdy, P.H., Blackburn, H.D., Dzakuma, J.M. 2004. Spanish buck ss-b inhibin/activin (INHBB) microsatellite polymorphisms. American Society of Animal Science/American Society of Dairy Science/Poultry Science Association Annual Meeting, July 25-29, 2004, St. Louis, Missouri. Journal of Animal Science Supplement 2004. 82(Suppl 1): 377-378.
Inha Microsatellite Polymorphisms in Angora Bucks - (Abstract Only)
Spiller, S.F., Ericsson, S.A., Realivasquez, R., Campbell, W.T., Sterns, K.L., Purdy, P.H., Blackburn, H.D., Dzakuma, J.M. 2004. INHA microsatellite polymorphisms in angora bucks. American Society of Animal Science/American Society of Dairy Science/Poultry Science Association Annual Meeting, July 25-29, 2004, St. Louis, Missouri. Journal of Animal Science 2004. 82(Suppl 1):378.
Effects of the Flavonoids, Silibinin and Catechin, on the Motility of Extended Cooled Caprine Sperm - (Peer Reviewed Journal)
Purdy, P.H., Ericsson, S.A., Dodson, R.E., Sternes, K.L., Garner, D.L. 2004. Effects of the flavonoids, silibinin and catechin, on the motility of extended cooled caprine sperm. Small Ruminant Research. 55:239-243.
Effect of Cholesterol-Loaded Cyclodextrin on the Cryosurvival of Bull Sperm - (Peer Reviewed Journal)
Purdy, P.H., Graham, J.K. 2004. Effect of cholesterol-loaded cyclodextrin on the cryosurvival of bull sperm. Cryobiology. 48:36-45.
Current Status of Cryopreserving Goat Semen - (Abstract Only)
Purdy, P.H. 2003. Current status of cryopreserving goat semen. Annual Meeting for the American Society of Animal Science, June 25-27, 2003, Phoenix, Arizona.
ARS News Articles
Last Modified: 10/22/2014