Author
 |
Johnson, Lawrence |
|
Welch, Glenn |
|
Submitted to: Theriogenology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 10/13/1999 Publication Date: N/A Citation: N/A Interpretive Summary: Sex control for livestock production is one of the most sought after technologies of the modern day. Its usefulness in various species and in a wide range of markets has been demonstrated over and again. This paper describes the adaptation of the Beltsville Sperm Sexing Technology to the most recent technological advance in cell sorting, the high speed cell sorter. The original procedures were adapted from a system that sorted less than a half million sperm per hour to the new high speed system which for specific purposes can sort upwards of 15 to 20 million female producing X sperm in an hours time. Routine sorting of both X and Y sperm is shown to easily be accomplished at a rate of 6 million per hour. This new and improved technology for sexing sperm makes the Beltsville sexing technology applicable in a wider range applications in animal and human applications. Technical Abstract: Sex preselection that is based on flow-cytometric measurement of sperm DNA content to enable sorting of X- from Y-chromosome-bearing sperm has proven reproducible at various locations and with many species at greater than 90% purity. Offspring of the predetermined sex in both domestic animals and human beings have been born using this technology since its introduction in n1989. The method involves treating sperm with the fluorescent dye, Hoechs 33342, which binds to the DNA and then sorting them into X- and Y-bearing- sperm populations with a flow cytometer/cell sorter modified specifically for sperm. Sexed sperm are then used with differing semen delivery routes such as intra-uterine, intra-tubal, artificial insemination (deep-uterine and cervical), in vitro fertilization and embryo transfer, and intra- cytoplasmic sperm injection (ICSI). Offspring produced at all locations using the technology have been morphologically normal and reproductively capable in succeeding generations. With the advent of high-speed cell sorting technology and improved efficiency of sorting by a new sperm orienting nozzle, the efficiency of sexed sperm production is significantly enhanced. This paper describes development of the these technological improvements in the Beltsville Sexing Technology that has brought sexed sperm to a new level of application. Under typical conditions the high- speed sperm sorter with the orienting nozzle (HiSON) results in purities of 90% of X- and Y-bearing sperm at 6 million sperm per h for each population. Taken to its highest performance level, the HiSON has produced X-bearing-sperm populations at 85-90% purity in the production of up to 11 million X- bearing-sperm per h of sorting. Sexed sperm on demand has become a reality through the development of the HiSON system. |
