False Pregancy

Gilbertowner · Post by **Gilbertowner** » Sat Mar 19, 2011 12:34 pm

Our 4Her needs your input.

He has to do a presentation on a sow that went through false pregancy. Does any one have 1st hand knowledge on this subject.

Thanks in advance.

drw · Post by **drw** » Mon Mar 21, 2011 10:31 am

This from North Carolina State:
Pseudopregnancy (or false pregnancy) is difficult to understand, diagnose or prevent. In brief, pseudopregnancy can occur when all of the embryos are resorbed after the maternal recognition of pregnancy (days 10-15 postmating) and before fetal calcification (days 35-40 of gestation). Although the embryos are lost, the sow's ovaries continue to function as if the animal was pregnant. Consequently, the sow remains anestrus for prolonged periods, often as long as 115 days. These animals may exhibit varying degrees of udder development, yet fail to deliver any pigs, alive or dead. Unfortunately, producers often mistakenly diagnose these animals as pregnant when pregnancy status is assessed with ultrasound instruments or visual inspection.

It is important to consider the potential infectious agents or causes of embryonic loss between days 10 and 35 of pregnancy. Epidemics of porcine parvovirus, porcine pseudorabies virus and potentially PRRS virus can cause abrupt reductions in farrowing rates and increased numbers of irregular returns to estrus (outside the typical 21 day interval) and pseudopregnancy. However, infectious agents typically induce other reproductive problems that accompany the increased numbers of pseudopregnant sows.

Increased conception failures and increased embryonic mortality often result from elevated ambient temperatures. The highest rate of embryonic mortality appears to occur when females are heat-stressed around the time of implantation. Since the maternal recognition of pregnancy has commenced around the time of embryonic loss, the sow will return to estrus at an irregular interval, have a reduction in litter size or become pseudopregnant. In addition to heat stress, other stressors, such as regrouping sows at two weeks after breeding, may interfere with implantation and maintenance of early pregnancy.

Other potential causes of prolonged anestrus in sows include cystic ovaries, zearalenone toxicity and endometritis/metritis. These conditions may interfere with the normal estrous cycle of a sow, thereby, resulting in erroneous classification of pregnancy. Our previous research indicated that less than 20% of pseudopregnant sows were affected with any of these conditions and their importance should not be over rated.

LargeMouth · Post by **LargeMouth** » Mon Mar 28, 2011 9:32 pm

I actually have had this happen to me, put sow in crate 5 days prior to "due date" appeared to look very piggy as I figured she had a large litter in her and even started to produce milk near her due date. Never went into labor or had her first pig, milk went away and her belly shrank down to normal size. Ended up shipping sow and moved on.

whatwasIthinking · Post by **whatwasIthinking** » Mon Mar 28, 2011 10:11 pm

I have had the same thing happen twice. My problem was caused from the feed. At first, all three of my sows did not take. My fourth pig took, or so I thought. Upon reading through these blogs, I found several breeders were having the same problem and we were all feeding Purina Pork and Sow builder. I took them off that feed and have been successful in getting all bred except the one that went through the Pseudopregnancy. There are many websites with information on feed toxins. Good Luck.

Gilbertowner · Post by **Gilbertowner** » Tue Mar 29, 2011 8:34 am

Can you tail bleed a sow like we do our cattle to check to see if they are preg or not?

Is there another test you can do to check if they are settled or not?

DrAmy · Post by **DrAmy** » Wed Mar 30, 2011 1:42 pm

There is not a blood pregnancy test for sows like there is for cows. The only way to check is with ultrasound - and real-time is better and more accurate than a Preg-Tone. Some trained vets can rectally palpate a sow somewhat successfully, but ultrasond is the best and most routine method.

Gilbertowner · Post by **Gilbertowner** » Thu Mar 31, 2011 2:10 pm

so no peeing of a stick either...