Index drops 0.2% led by exchange operator.

Supplier Synlait also rebounds strongly.

Company's stock worst performer, down 2.7 per cent.

Synlait gains manufacturer registration for a2 Milk's China label infant formula.

NZ Refining stock falls amid pipeline repiar, while Synlait retreats from high.

The company posted an 11 per cent gain in full-year profit and flagged further growth.

Synlait Milk has gained a GRAS notice from the FDA for its lactoferrin.

Synlait Milk posted a 3.8 per cent lift in first-half profit.

Friesland Compina will sell its 8.17 per cent stake in Canterbury's Synlait Milk to a2 Milk.

South Island dairy products processor Synlait Milk has increased its forecast farmgate milk price by $1 to $6 per kilogram of milk solids.

Some dairy farmers in the South Island might have to dispose of their milk due to road closures and other issues.

A big increase in formula sales has driven NZX-listed Synlait Milk to a record profit.

Synlait Milk says its annual profit more than doubled on sales of higher-margin products.

Synlait Milk said its forecast milk price for the 2016/2017 would carry a higher-than-usual advance rate for milk suppliers.

Synlait Milk said it was on track towards racking up its most profitable year ever after a big increase in infant formula sales drove its first-half earnings sharply higher.

Synlait expects premium payments to its farmer suppliers to double, mainly on the back of a boom in infant formula sales.

The South Island dairy processor will need to consider investing in expansion given the rapid growth of A2, analysts say.

Synlait Milk has revised its forecast milk price for the 2015 / 2016 season from $5.00 per kilogram to $4.20.

Rakaia-based Synlait Milk has issued a low farmgate milk price for the current season but managing director John Penno says he expects prices to start improving by early next year.

The sale of Lochinver station to Chinese interests spearheaded by Shanghai Pengxin reignited concerns about farm sales to foreigners during the election campaign.

Fran O'Sullivan asks, when is enough enough when it comes to Chinese investment in the New Zealand dairy sector?

Milking cows under the cover of darkness has helped to produce a milk powder high in the sleep-promoting hormone Melatonin.

Synlait Milk's share price has tumbled after the Canterbury-based specialised milk powder manufacturer reported a $6.4 million net loss for the six months to January.

All of the samples of infant formula tested by police after being suspected of possible tampering have tested negative for 1080.

Authorities are no closer to saying if the threat to poison baby formula with 1080 was a hoax, or who wrote the blackmail threats - even with 30 staff on the case.

Police are testing infant formula after a number of tins were found with pin-pricks in packaging lids.

Dairy companies are confident security measures at their facilities are tight enough to prevent a 1080 contamination.