Controlling stillbirth rates in highly prolific sows can be a challenge. The rate of farrowing difficulties (dystocia) reported in the literature seems to lie somewhere between 10-55%. The rate of intervention will vary from herd to herd depending on a wide variety of factors such as genetics, sow body condition, mycotoxins, parity structure , disease etc etc. The sequence of events that prescribe for intervention in a difficult farrowing can also vary from herd to herd. Some jump in very quickly and others allow for a greater “tincture of time”. Manual obstetrics (MO) is used as an intervention to counteract the negative effects of dystocia. In the literature the data on birth intervals between piglets that is associated with an increased risk of stillbirth varies between 30 to 60 min. These German researchers wanted to evaluate a specific manual obstetric intervention protocol in a highly prolific sow herd with the goal of reducing the stillbirth rate. The study included 210 births of Yorkshire Landrace hybrid sows housed in crates. The sows either farrowed spontaneously (G1, n=70) or were treated with cloprostenol to induce parturition on the 114th day of gestation with a result that induced sows farrowed within 12-24 hours (G2, n=63) or after >24 h (G3, n=77). MO was administered if the interval between two piglets exceeded 60 min after the 1st piglet, 45 min after the 2nd to 5th piglet and 30 min after the 6th 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.
The researchers found the following:
- In litter size 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 Parity≥5 than in Parity 2-4 and Parity 1 (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%.
- Stillborn piglets increased linearly with the relative birth rank (farrowing order) and averaged 5.2%.
- At litter size of W≥23, the stillbirth rate was twice as high as for litter sizes up to 18 piglets. ( The researchers note that this was despite more frequent manual obstetrics (MO) being applied.
Take Home Message:
- The finding that sows treated with cloprostenol to induce parturition on the 114th day of gestation resulted in 63 sows that farrowed within 12-24 hours (G2) or 77 sows that farrowed after 24 h (G3) seems somewhat disappointing. This wider window of farrowing increases the challenge of having farrowing room staff available to monitor and intervene in a difficult farrowing.
- The researchers conclude that the low overall stillbirth rate of 5.2% indicates that this manual obstetric intervention protocol shortens the duration of parturition and reduces stillbirths, especially in sows that are parity ≥5th litter. They do not, however, offer results for stillbirth rate if the manual obstetrics were not applied as a control.
- The use of manual obstetrical intervention can yield a positive result but the reduced stillbirth rates must be weighed off against the cost of having farrowing room personnel available as sows farrow out as well as the risk of trauma and infection of the birth canal during manual obstetrics. Both of these risks can be mitigated through appropriate obstetrical manipulation training as well as proper obstetrical hygiene.
Reference: H Haller , L Wahl , J Kauffold Investigation into the use of an obstetric intervention protocol in high-prolific sows with and without parturition induction Tierarztl Prax Ausg G Grosstiere Nutztiere . 2025 Oct;53(5):301-309. doi: 10.1055/a-2681-7528. Epub 2025 Oct 15.
