What to do if the sow goes 7 days past her due date? An old vet teaches you how to avoid piglet deaths
Generally speaking, the gestation period of a sow averages 114 days. The length of gestation varies somewhat depending on the breed of pig, but individual differences are even more pronounced. Delayed farrowing in sows is an abnormal reproductive phenomenon that occurs frequently in pig production, and its appearance will more or less affect the farrowing outcome of the sow, causing economic losses to varying degrees.
1. Causes of delayed farrowing in sows
Delayed farrowing in sows is an abnormal reproductive phenomenon that frequently occurs in pig production. If a sow gives birth 4 days later than the average farrowing date, the piglets will be larger at birth with longer hair coats, but their nutrition may not necessarily be good, and their vitality will also be affected. If farrowing is delayed by 7 days, stillbirth of the entire litter is very likely, and even because the fetuses die in the womb, the farrowing period will continue to be delayed until manual intervention is applied. Because the environment differs, the reasons for delayed farrowing in sows also differ. The most likely causes are the influence of high temperatures or infection with porcine parvovirus, Japanese B encephalitis virus, or porcine reproductive and respiratory syndrome virus, causing fetal death. After the due date, because the fetuses have no vitality and cannot stimulate the uterus, the body's response to pregnancy is not strong, thus causing the sow's farrowing period to be delayed.
2. You need to understand how to calculate the due date of a pregnant sow
When mating sows, the mating date and the breed and number of the boar used for mating must be recorded in detail. Once a sow is confirmed pregnant, the due date should be calculated to facilitate feeding management and preparation for farrowing. The gestation period of a sow is generally 110-118 days, with an average of 114 days. Therefore, the due date of a sow is calculated based on 114 days, and can be calculated by the following methods:
The sow is 7 days past her due date? An old vet teaches you how to avoid piglet deaths!
(1) The three, three, three method. For ease of memory, the gestation period of a sow can be recorded as 3 months, 3 weeks and 3 days.
(2) The method of adding 3 to the mating month and 20 to the mating day. That is, add 3 months to the mating month of the sow, add 20 days to the mating day, and the resulting date is the sow's due date.
3. Clinical symptoms of sows past the due date
Generally, there is poor appetite, reduced frequency of urination, a tendency to lie down, and feed intake gradually decreasing to refusal to eat. The sow lies down and cannot get up, and body temperature is not high. Both ears are cold, heartbeat is rapid, breathing is difficult, conjunctival congestion of the eyes, dry and hard stool, and scanty dark yellow urine.
4. How to correctly handle the problem of delayed farrowing in sows
(1) In terms of management, treat sows about to farrow like pregnant women: conduct prenatal observation of sows about to farrow every day, and check the fetal movement of the embryos. Pay special attention to the feed intake of sows before farrowing, as this is a direct reflection of the sow's health status. If feed intake stops a few days before farrowing, the sow may have a cold or fever, and timely diagnosis and treatment are needed. If it is unrelated to disease, it is very likely a sign of imminent farrowing, and this needs to be distinguished. However, according to relevant information, if feed intake stops 2 days before farrowing, the farrowing process will be prolonged and the incidence of dystocia will increase.
(2) Review the mating records: were the mating circumstances really recorded accurately? Has there been any return to estrus? If it is confirmed that the mating records are accurate, active measures to induce farrowing in the sow can be taken. It is recommended to use cloprostenol rather than oxytocin. Oxytocin should be used during the farrowing process of the sow, and attention should be paid to using an appropriate dose.
(3) In production, conventional measures to actively adjust the farrowing time of sows are adopted. This measure is mainly used for sows to farrow during the day or to farrow synchronously.
The drug used is cloprostenol. For sows about to farrow at 112—113 days of gestation, treatment is carried out at 10:00 every morning, and the sow will usually farrow after 20—30 hours, thereby prompting 85% of sows to farrow during the day, which facilitates care by the feeding staff and prevents the occurrence of stillbirth and dystocia.
(4) Because there are many causes of stillbirth and mummification, such as insufficient nutrition, the sow eating moldy feed, or the sow being infected with Japanese encephalitis, parvovirus, pseudorabies, swine fever, etc., feed quality must be strictly controlled and comprehensive prevention and control of the above diseases must be carried out well.
(5) Early detection of delayed farrowing is necessary and is also a positive and effective way to reduce losses. If early on the mammary glands are found to be well developed, but milk regression occurs before the due date, it is necessary to pay special attention and take necessary rescue measures.