[Experiences with segregated early weaning (SEW) in of swine]

The ongoing trend towards SEW has arrived the eastern European countries as well. In order to examine the effect of 17 days weaning on production in a large pig production unit there were the following evaluations, carried out in the following steps: Step one: Two groups of sows were randomly formed before weaning: Group one (90 sows) were weaned at day 21 of lactation. Group two (109 sows) were weaned at day 17 of lactation. The following parameters were evaluated: A: Weaning to estrus interval in days B: Liveborn litter size at the following parturition Step 2: The number of weaned piglets that were the subject to the next evaluation were not the complete number of the weaned ones from the sows of group one and two, as due to technical reasons some of the animals could not be included in the second step of the evaluation. Group one: 901 piglets conventionally weaned at day 21 of lactation. Group two: 798 piglets SEW weaned at day 17 of lactation. The following parameters were evaluated during 6 weeks after weaning: C: Average daily weight (ADG) gain, measured weekly in gram in each group D: Mortality in percent in each group In step 1 the following results were evaluated: the sows in group one showed a significant shorter (p < 0.05) weaning to estrus interval when compared to the sows in group two (5.65 +/- 2.30 vs. 6.38 +/- 2.31), but there was no significant difference regarding liveborn litter size between the groups (10.87 +/- 2.01 vs. 10.74 +/- 2.22). Regarding step 2 the group two (SEW) showed, when compared to the group one (21 day weaning) during the first three weeks after weaning lesser weekly measured daily gains (185 +/- 13; 184 +/- 41; 361 +/- 23 vs. 201 +/- 11; 202 +/- 21; 365 +/- 32). Following the third week after weaning there existed a significant (p < 0.05) better weekly measured average daily gain in the SEW weaned group (group 2) when compared to group one (401 +/- 34; 412 +/- 30; 439 +/- 41 vs. 433 +/- 29; 465 +/- 31; 543 +/- 29). Regarding mortality both of the groups revealed a very low percent of losses (group one 0.89% vs. group two 0.75%), which differences were not significant. Step 3: retrospective evaluation of culling of the sows. Group one (412 sows) were SEW weaned in three consecutive weaning at day 14-17 of lactation. Group two (597 sows) were weaned in three consecutive weaning at day 21-28 of lactation. The reasons for culling included no observed postweaning estrus, repeat breeders, abort, small litter size, locomotor problems, periparturient diseases (PDC/MMA), small weaning litter weight, old age, urogenital diseases, overweight. The calculated average "Culling Rate" showed no significant differences between the groups (46.4% in group one vs. 47.1% in the group two).