This is illustrated in Figure 1. North Carolina State University. Figure 1: Relationships among litter characteristics of total number of pigs born, mummies and stillborns and timing of death losses during pregnancy. In contrast, the number and size distribution of mummified fetuses within a litter is very useful in determining when and, to some extent, what type of stresses affected the sow between days 40 and of pregnancy.
If the mummies are all fairly consistent in size, then this typically is due to an acute stressor that affected the sow relatively over a short time interval such as heat stress, fighting after mixing sows in pen gestation systems and some diseases. If the mummies within the litter vary in size from small and highly decomposed to large and mostly intact, then this usually is representative of a chronic stressor which has occurred over a long period of time. The smallest fetuses are the most vulnerable so they die first, but over time the larger ones also are affected as the stress persists.
In theory, any acute stressor also can be a chronic stressor if it occurs at a reduced magnitude over a longer period of time. The most common examples are exposure to high humidity and temperatures in the upper degrees Fahrenheit for several months as is common during the summer and diseases such as porcine reproductive and respiratory syndrome when sows are infected early in gestation. In some situations, the presence of small mummies may not be related to negative management conditions.
Highly prolific sows usually have more embryos after breeding than their uteri can support during pregnancy. Where stillbirths are excessive, a full veterinary investigation is needed to highlight the contributory factors. In addition to correcting any environmental problems temperature and space provision , sow condition and nutrition problems, the key to reducing stillbirth rates is supervision of farrowing.
If financial constraints prevent supervision then a higher level of pigs born dead - as well as a higher neonatal mortality - can be expected. Supervision may be improved by induction of farrowing using prostaglandins with or without Oxytocin-like products but once farrowing has started, the intervals between piglets' deliveries should be recorded.
As a general guide, a 'normal' farrowing would typically involve delivery of a few piglets followed by a 'rest' period of up to 90 minutes before starting again. However, any delay beyond minutes since the last pig, in the second half of farrowing is likely to lead to later born pigs arriving dead. Traditionally, small doses 0. A longer acting analogue Reprocine : Vetoquinol is now available and can be given as a single dose once farrowing has started, and will give waves of uterine contractions - accelerating farrowing - over a 6-hour period.
The actual dose used is critical and should only be used as directed by the herd's veterinary surgeon. Before using either traditional Oxytocin or the long acting alternative, always ensure that there is no obstruction in the birth canal. Once delivered, early and appropriate action may be needed to clear the airways of fluid and allow unassisted respiration.
As a final comment, the old fashioned use of well soaked bran in the 48 hours prior to farrowing can significantly assist speeding up of farrowing, reducing stillbirths as well as helping milk production and is particularly relevant for herds in which sows are removed from straw based dry sow accommodation into fully slatted or unbedded farrowing pens. Management problems will recur particularly in circumstances where farrowings are not attended. Stillborn pigs are found dead in the membranes behind the sow or delivered dead as a result of assistance at farrowing or following uterine inertia during prolonged farrowing.
Piglets found dead in the membranes behind a sow may be stillborn, but the point of death should be confirmed by post-mortem examination. A history of uterine inertia or assistance at farrowing may explain the stillbirths. Piglets of older sows or those with large litters are most likely to be born dead in the other products of parturition, as mummified piglets frequently cause delay to the piglets which follow them.
The cause of death may be congenital and the piglet may be malformed or so small as to be non-viable. Culture or demonstration of infectious agents may suggest a cause. Animals which have died from carbon monoxide poisoning are often cherry red. Stillborn pigs have a fleshy cord, membrane on the skin and cartilaginous curled up tips to the toes.
Those that died during without breathing have lungs which are non-expanded, resemble liver and sink in water. Top story. Tue Aug 09 While it is possible for some of the piglets to be born dead, if it happens several times with the same sow, then there must be a reason.
First you need to establish whether the piglet was born dead or if it died soon after birth, and could have been saved if the problem had been noticed earlier. Vision Reporter Journalist New vision. Some piglets are born so weak and the membrane in which they are enveloped, and they suffocated in.
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