[Investigation into the use of an obstetric intervention protocol in high-prolific sows with and without parturition...

According to the literature, the dystocia rate in sows lies between 10-55%. Manual obstetrics (MO) is used to counteract the negative effects of dystocia, such as increased stillbirth rates. Data on birth intervals associated with an increased risk of stillbirth, vary between 30-60 min. With increasing farrowing duration in today's high-prolific sows farrowing supervision with appropriate obstetric intervention are increasingly relevant. The aim of this study was to test a differentiated obstetric intervention protocol in high-prolific sows to reduce the stillbirth rate. The study aimed to contribute to the harmonization of data on the birth physiology of these animals and to elucidate the frequency of necessary obstetric interventions.210 births of Yorkshire Landrace hybrid sows housed in crates were observed. The sows farrowed spontaneously (G1, n=70) or were treated with cloprostenol to induce parturition on the 114th day of gestation and farrowed within 12-24 h (G2, n=63) or after >24 h (G3, n=77). MO was administered if the interval between two piglets exceeded 60 min after the 1^st, 45 min after the 2^nd-5^th and 30 min after the 6^th and subsequent piglets. The births were grouped according to birth induction (G1, G2, G3), parity (P1, P2-4, P≥5) and litter size (W5-14, W15-18; W19-22, W≥23) and compared in terms of farrowing characteristics.In W19-22 and W≥23, MO was performed more often than in smaller litters (81.1% and 85.2% vs.≤60%; p≤0.02 respectively). MO was performed more frequently in P≥5 than in P2-4 and P1 (87.7% vs. 73.3% and 60.3%; p≤0.05 respectively). In the second half of the birth, the rate of MO was more than twice as high as in P1 and P2-4 at 30-60%. The proportion of stillborn piglets increased linearly with the relative birth rank and averaged 5.2%. At W≥23, the stillbirth rate was twice as high as for litter sizes up to 18 piglets, despite more frequent MO.The low stillbirth rate indicates that the obstetric intervention protocol shortens the duration of parturition and reduces stillbirths, especially in sows≥5th litter. However, its use has to be negotiated against economic (availability of personnel) and hygienic aspects (risk of infection due to frequent MO).