Genomics - FAQ
Why are there so many new high genetic merit bulls?
With genomic selection now available, new Holstein sires graduated that would not have been available for another two or three years if we had continued to use the old sire evaluation system. The advantage we gain from genomics is that we can now predict the genetic merit of our you animals at a much higher reliability earlier than we could with simply the use of traditional parent averages. This gives dairy producers the potential to make significant genetic progress in their herds.
What is genomic selection?
Genomic selection is predicting the performance of an animal's offspring based on the DNA of that animal. Recent breakthroughs from industry-supported research have resulted in new tests that look at thousands of DNA markers of an individual bull or cow. The DNA markers of the individual animal are compared to the marker profiles of thousands of bulls and cows with millions of offspring with known performance for the various traits of interest. This allows an estimation of breeding values of an animal based on associations between DNA marker profiles and milk yield, Somatic Cell Score, Productive Life and other important traits.
Genomics: A Revolutionary Tool|
Genomics. It all started in 2004 when researchers sequenced the cattle genome. They used a Hereford for the project and discovered the bovine is made up of 30 chromosomes and three billion bases or nucleotides...those little letters.
To visualize this, picture a cell. Among other things, a cell contains those 30 chromosomes. The chromosomes consist of deoxyribonucleic acid, which is just a big fancy word for DNA. Looking closely at DNA, you can see it is made up of nucleotides - the As, Ts, Cs and Gs. The sequences of these little letters are what contain the instructions for making proteins. Proteins are the building blocks of life, ultimately determining the phenotype of animals.
Good Oestrus Detection
Without good oestrus detection, it does not matter how good an inseminator is; cows just will not conceive.
Cows ovulate approximately 24 to 30 hours after the beginning of oestrus or 12 -14 hours after the end of oestrus. However, semen must be deposited in the female reproductive tract several hours before ovulation to insure high conception rates. Cows remain in oestrus for 8 - 16 hours.
The average life span of an ovum (egg) in the female reproductive tract is about 8-12 hours. The life span of sperm in the reproductive tract is about 30 - 48 hours. Therefore, it is better to inseminate too early rather than too late. However, on time is the best.
Working With British Diary Farmers to Maximise the Profitability of the Herd