Inland dairy farmers could squeeze an extra $129 worth of milk from each of their cows simply by feeding them each $2.84 worth of table salt in the milking season, says an AgResearch scientist.
Mike O'Connor told a Grasslands conference in Invercargill that a study had shown salt increased milk
production by 12.8 per cent - with no effect on milkfat or protein concentrations.
The research was done at a Rotorua dairy farm.
Ninety cows were paired, based on breed, age, calving date and previous milk production.
The pairs were then split between two treatment groups.
One group received a daily drench of 14g of sodium for each cow (from 35g salt) while the other group remained undrenched.
Fortnightly milk production measurements were taken over three months, with fat and protein analyses. Saliva samples were also taken from 10 randomly chosen animals from each group.
These were analysed for sodium and potassium.
Mr O'Connor said inland soils lacked sodium, which was more common on farms closer to the coast where salt-laden winds blew in from the sea.
He said salt supplementation could prove to be worthwhile.
If extended to the full lactation period it could give extra income of $129 a cow (at $3.50kg milk solids) for a cost as low as $2.84.
He said salt could also be supplemented through dusting and fertilising.
It was less effective if added through water troughs and licks or blocks, Mr O'Connor said.
The Ruakura scientist said sodium deficiencies were likely to become more common in the future.
- NZPA
