ACGA Merrrit is the name of the Australian Cashmere Grower's Association performance register and genetic analysis project.
It is quite straight forward to record your animals in ACGA Merrit. The steps are:
1. Become a financial member of the ACGA
2. Eartag your kids, record their gender, birthdate and parentage. Try to get this as accurate as possible but some leeway is OK. Record this data in the Merrrit datasheet (available form the ACGA)
3. Shear the kids as yearlings and two year olds. Weigh, subsample and test the fleece for fibre diameter and yield.
4. Record the fleece data in the Merrrit datasheet.
5. Send the data off to the ACGA for analysis.
6. If you have genetic links to other ACGA Merrrit herds, you will get across herd estimated breeding values (EBV). If your flock is unlinked you will get within herd EBVs.
Australian Cashmeres were first domesticated from ferals in the 1970's. Breeders started collecting performance data on animals soon thereafter. So whilst the formal work that went into establishing Merrrit did not commence until the 2000s, the database goes back as far as animals born in 1982. So its possible to see trends in EBVs since that early base.
Merrrit EBV plot
The plot shows the average EBV for fibre diameter and down weight for animals born in a particular year. The red line indicates the genetic correlation between fibre diameter and down weight. Coarser animals produce more cashmere than finer animals.
There are two phases of improvement evident in the data. In Phase 1, improvements were made to the fineness of the animals and slow improvements were made to overcome the genetic correlation between down weight and fibre diameter.
In Phase 2 of the improvement effort, rapid simultaneous improvement of down weight and fibre diameter occurred. This is the time when formal 'Benchmarking', 'Sire Referencing' and 'Performance Recording' projects were conducted and ACGA Merrrit was established.
The ACGA Merrrit computer program that generates the EBVs uses the performance data of the individual animal, that of all known relatives and that of other animals in the same group to come up with the most accurate test of an animal's genetic worth.
The breeder can then very accurately compare the relative merit of animals born in a different years or in different breeder's herds. In this way it is possible to identify the best animals to use in breeding the next generation and therefore make much faster genetic progress.