Strong link between SCC and age profile
Analysis has shown a linear increase in SCC levels in dairy herds in line with the increasing age of the cows in the herd, and the age of the herd also has an impact on milk yield.
Tom O’Dwyer, Teagasc, Kildalton said that one in three dairy cows is milk recorded, according to the 2002 Irish Cattle Breeding Federation report. Analysis of records showed that the target average of 365 day calving interval was not being met for Holstein Friesian cows; an interval of 383 days emerges from the figures.
Milk solids were highest in fourth lactation cows, but SCC levels increased by 17% in all cows when they entered their fourth and fifth lactations, rising from 182,000 to 213,000 cells.
The highest protein levels were recorded for cows in their second and third lactations, declining for older cows.
