Automated oestrus detection and North American Holstein genetics in pasture based dairying in New Zealand
Summary
The aim of this project is to investigate the possible difference of functioning of the CSD, comparing cows with a major North American Holstein influence with more typical New Zealand Friesian-Holstein and Jersey animals. Therefore data from the 2003 trials are reanalyzed after allocating the animals into groups based on their genetic merit.
The central query in this research will consequently be:
“Does the use of the CSD cause a greater or lesser improvement in oestrus detection in a high North American Holstein strain of cows compared with strain with lower Holstein influences?”
The differences may be interesting, especially now poorer fertility in animals with high North American Holstein (NAH) genetics becomes more evident all over the world and suboptimal expression of oestrus if hypothesised to be one of its causes.
Besides the data analysis of the previous trials the author was also involved in a new trial, started in the 2006 mating season. Aim of this trial was to integrate the CSD with an automatic identification system, the next step in developing a fully integrated system of detecting heat and drafting oestrous animals for insemination.