in a quadratic response (P < 0.01). This latter response was largely attributed to the additional feed allowance provided to sows during parity 5 and 6. Return-to-estrus intervals were similar among parities. Sows lost more BW during lactation 1 and 2 than from parity 3 to 5, whereupon weight loss increased in parity 6 resulting in an overall quadratic (P < 0.05) weight change for the 6-parity period. As a result, backfat thickness declined from parity 1 to 4 but increased to parity 6, resulting in an overall quadratic parity response (P < 0.01). A quadratic decline in milk fat content occurred at weaning to parity 4, whereupon it increased to parity 6 (P < 0.10), responses also consistent with changes in backfat thickness.