"Softer prices likely reflect a lift in offer volumes, which were up on the previous event," Gibson noted.
At the latest GDT auction, cheddar plunged 14 per cent to US$3,950 a tonne, while butter sank 10.3 per cent to US$4805 a tonne.
Butter milk powder dropped 10.1 per cent to US$2807 a tonne, while anhydrous milk fat retreated 5.7 per cent to US$5752 a tonne.
"Anhydrous milk fat prices were driven by a decrease in price across all contract periods, particularly July deliveries indicating the market had adequate cover for these near term delivery dates," said Gibson. "Butter prices decreased significantly across all delivery dates from August to November."
Skim milk powder gave up 4 per cent to US$2436 a tonne. "Prices decreased across all delivery dates, with the decline in prices likely being influenced by offer volumes leading into this event which were up 36 percent on the previous event," according to Gibson. "Markets may also be anticipating adequate spring milk supplies, which at this point are looking positive."
Bucking the trend, rennet casein climbed 4.2 per cent to US$7201 a tonne, while lactose added 0.4 per cent to US$897 a tonne.
For sweet whey powder, no product was offered or sold, or no price was published for the last event, or on both of the two previous events.
The New Zealand dollar last traded at 66.14 US cents as of 3.15pm in New York, compared with 65.98 US cents at the previous close in Wellington.
There were 107 winning bidders out of 148 participating at the 13-round auction. The number of registered bidders was 526, up from 524 at the previous auction.