29 March 1996

Long lactations for the record

MILK producers interested in extended lactations must base decisions on production records.

Genuss Dr Brian McGuirk acknowledged the benefits of extended lactations also detailed by the Hannah Research Institutes Dr Chris Knight. Dr McGuirk gave examples of extended lactations of animals in Genuss MOET nucleus herd, where 14% of heifers have lactations above 500 days.

Average daily yield for 40 heifers milked three times a day and fed a complete diet was 23.5kg at 500 days. Five heifers were taken on to 900 days, one of which gave over 30kg/day at 700 days.

"Producers must establish what is a profitable level of milking at 305 days. We have preached that 365-day calving intervals are the most profitable. But the case with the higher yielder where output may yield profit beyond the 305-day lactation could be considered. But Dr McGuirk advised identifying animals that could suit extended lactations from previous individual records.

before extending lactations.

"Seasonality payments should also be taken into account. Only then could the calving interval of certain cows be increased," he said.

Brian McGuirk:"A profitable milking level at 305 days?"