I ran across an article at The Beef Site that I found quite interesting. Back in the 1960's some semen was collected from bulls, processed and stored in liquid nitrogren at the USDA National Germplasm Conservatory – a sperm and embryo cryobank – in Fort Collins, Colorado.
Recently some calves were born and Louisiana Agricultural Centre from some 40-year old semen that was used to AI about 200 cows. With live calves on the ground born from this stored semen, scientists see two positives effects for the beef and dairy industries.
1. Germplasm banks that are storing frozen semen have a product that we know will work for livestock producers
2. Strides have been made in genetics, and some small differences in DNA – single nucleotide polymorphisms or SNPs – have been shown to be positive production modifiers that can and likely will be used to increase animal production performance.”
*SNPs can act as biological markers, helping scientists locate genes that are associated with a variety of traits, such as growth, milk production and disease susceptibility. Some of the older bulls in the study may have had these SNPs, and with our advance in technology scientists will be able to identify SNP's and different traits to help improve production.
To read the whole story check it out here