The effects of reducing the frequency of milking of cows in late
on milk somatic cell count (SCC), polymorphonuclear leucocyte (PMN) content,
chemical composition and proteolytic activity were investigated. Intermittent
milking is frequently practised by Irish farmers in late lactation, and
of this study was to determine whether this procedure could be linked to
quality of milk. Seventeen Holstein Friesian cows in late lactation (>215
d in milk)
were assigned to two treatment groups, and were either milked twice a day
drying-off (control group) or milked intermittently as the yield fell (test
composition and enzymic characteristics were measured on two occasions.
first sampling, day 7, test cows were on once daily milking and at the
second, day 15,
the test cows were being milked every second day. Milk yields were significantly
lower in test than control animals and decreased between days 7 and 15
groups. Milk SCC and PMN levels were increased on reducing milking frequency
at day 15, the increase was not linked to decreased milk yield. Milk lactose
significantly decreased and pH, α-lactalbumin levels, plasmin activity
plasminogen activity significantly increased by reducing milking frequency.
conclusion, reduced frequency of milking in late lactation leads to the
milk that is abnormal in character and this may be linked to reduced quality
products manufactured from such milk.