The good times being enjoyed by sheep farmers are mostly due to a favourable exchange rate.
Meat and Wool New Zealand's Economic Service executive director, Rob Davison, said export lamb prices from last October to this March were up 27%, to $8670 a tonne, compared with the corresponding period the previous year.
But 18% of that increase was because of a more favourable exchange rate.
On a trade-weighted basis, the exchange-rate effect had boosted lamb returns 18% over that period, while global market prices had increased just 5%, Mr Davison said.
Export lamb volumes to Europe were 5% higher for the first four months of this year than for the comparable period last year.
Schedule prices continue to rise, a week ago lifting a further 10c a kg, and he expected average lamb prices to increase from $57 a head last year to between $80 and $85.
Mr Davison said lamb sales were benefiting from European supermarkets promoting a "have a meal-at-home occasion".
However, this was at the expense of the restaurant trade, which was weakened by fewer customers.
"This, in particular, has put mid-market restaurants and their suppliers under pressure," he said.
The well-documented world shortage of lamb meant more New Zealand product was being sold as higher-value chilled and targeted at higher-paying markets.
Mr Davison said because of the lower export volume, 25% of New Zealand export lamb would be sold as chilled this year, compared with close to 20% last year.
Silver Fern Farms chief executive Keith Cooper said another element underpinning demand for lamb was countries concerned about a shortage of food.
"Surety and continuity of supply are becoming increasingly important," he said.
This had been noticeable in recent weeks as importers secured lamb supplies.
Mr Cooper said changes to the exchange rate were the only risk he could see to prices for lamb next season.
Mr Davison said the going was a bit tougher for beef, with United States beef prices last March 16% lower than in March 2008.
But with the favourable exchange rate, New Zealand prices were up 19%.
The exchange rate in March 2008 was US79c, compared with US57c last March.
Comparing the six months from October 2008 to last March with the corresponding period a year earlier, Mr Davison said export beef prices were 22% higher, at $5420 a tonne, all of that gain due to a more favourable exchange rate when assessed on a trade-weighted basis.
Remove the exchange-rate effect and world beef prices had actually fallen 5% over that period, he said.
Wool prices remained depressed due to the recession.
An initial assessment by Meat and Wool New Zealand of the impact on farmers of those returns showed the average farm profit before tax should increase from $16,700 in 2007-08 to $45,600 in 2008-09.