PERINATAL LOSSES - GENERAL CONDITION OF S OWS .2. EFFECTS OF OXYTOCINGIVEN FOR PARTUS SYNCHRONIZATION AND ACCELERATION OF FARROWING

In the veterinary practice, synthetic oxytocin is not only used in cas e of delay in labour and uterine atony. About 24 hours after the appli cation of prostaglandin F2alpha (PGF), partus synchronization can be o btained in sows. Acceleration of farrowing can be waited when oxytocin is applied just after the birth of the first piglet. Its application after the end of farrowing results in a milk ejection. In the present paper, the author investigated the effect of 10 IU oxytocin on the per inatal losses when given 24 hours after the administration of PGF, as well as after the birth of first piglet. On a farm operated with 6000 sows, two randomly selected experimental (A and B) and one control gro ups were investigated (the number of sows were 97, 98, as well as 96, respectively). For the sows of group A 3 mg of alfaprostole (Gabbrosti m) was given im. in the morning of the 113th day of pregnancy and 10 I U oxytocin (Oxytocin TAD) 24 hours later. Sows of the group B received 10 IU oxytocin im. just after the birth of the first piglet. Sows in the control group received 1 ml physiologic saline solution. The resul ts obtained have partly been analyzed for the whole group, partly in s ubgroups reflecting the general condition of sows (normal condition, m oderately fat, fat). Duration of farrowing, number of live-born and st ill-born piglets and early deaths formed the basis of analyses. Effect of PGF + oxytocin treatment was compared to the results of a prelimin ary PGF experiment while that of oxytocin to the data of the control g roup. It was found that significantly (p<0.05) less piglets were born in the group A (Table 1). This phenomenon dominated in the subgroup of sows with normal condition. For the totality of group B was also char acteristic that significantly lower was the number of live-born piglet s (p<0.05). In the group of moderately fat sows, the difference was co nsiderably significant (p<0.001). In the group of fat sows (Table 3), the duration of farrowing was significantly shorter than in the corres ponding control group (p<0.05). Delivery of oxytocin treated fat sows was shorter. Death of piglets during the first three days of life was significant in case of sows with abnormal general condition (p<0.05). Differences among the subgroups of A and B experimental and control gr oups was also significant (p<0.05 - p<0.001). Oxytocin did not influen ced the circumstances determined by the general condition of sows. Con clusions: routinely administered 10 IU oxytocin is a high dose from th e point of view of perinatal losses. Either administered 24 hours afte r PGF or after the birth of the first piglet, it has a harmful effect because it diminishes live birth. Its cause may be the tetanic contrac tion in the uterus causing a higher than physiologic hypoxia for the p iglets to be born. In fat sows, the effect of oxytocin is not unambigu ous. The number of live born piglets did not decreased significantly, the duration of delivery became shorter but the early perinatal piglet losses increased.