In a multi-parity sow experiment the effect of very restricted late pregnancy feeding on the incidence of agalactia was studied. A daily allowance of 1.0 kg was compared with 3.4 kg per day of a conventional cereal based sow diet. All sows were allowed free access to straw. The occurrence of agalactia was significantly lower and the rectal temperatures on the day of farrowing and the following two days were significantly decreased by the very restricted feeding regime during late pregnancy. A number of significant partial correlations between rectal temperatures and within litter standard deviations for weights, mortality and number of still-born piglets per litter were calculated. These correlations were significant even when agalactic sows (i. e. sows with rectal temperatures > 39.5 °C) were omitted from analysis, indicating a detrimental effect of subclinical agalactia on production performance.