due dates, earliest/latest pups being born - Page 2

my female that whelped on day 57 was bred 1 time, and it was her 21st day of heat.  really messed up cycle. 11 pups total, all survived

My very first litter was whelped on day 56 - 11 puppies, 10 survived. The 11th died within 72 hours (which can happen and is normal).

My second G-litter was born 4 years ago on day 70. That was scary and we took our female to the vet every day. But all vital signs were ok and she whelped three puppies - the first two were fine and the third (last one) was stillborn and could not be revived.

Back in April, one of my females was expecting a single puppy (according to ultrasound) and we had her monitored continously. On day 61 (her normal whelping day), the vet decided that the vital signs of the puppy were not the greatest and advised on a c-section. After a couple of discussions, we went for it. The little female looked premature (not in weight, but had lots of hair missing around the nose, the head and on her legs - a typical sign for a premie) and only lived for 4 or 5 hours. She had no interest in sucking or to keep warm. Even in the incubator, she felt chilled. I carried her around under my clothes on my skin the whole time until she died. It still makes me cry. Our female was always a great mother, whelped her litters effortlessly and never lost a puppy. To be truthful, I blame the vet for the loss of my puppy!

The SV had a publication (can't remember offhand where) that most litters were born on day 62, then day 61 (which is our most popular day) and day 60, and then day 63. Larger litters are born earlier and smaller ones might go later. If a breeding takes place a little early, the gestation time is longer than if the female is bred at the end of her heat cycle. And yes, even though I read that multiplie breedings should not cause the puppies to develop differently I still believe it does. Often, one or more puppies are significantly smaller and show signs of being premature.

Chris

A female could whelp any time between days 55-70 from the breeding date.  If you did more than one breeding, then you have to figure 55-70 days from both the first and last breeding to get the range of possible due dates. You can predict things much more accurately if you have progesterone or LH results taken at the time of the mating(s) because virtually all puppies are born between days 64-66 after the LH surge (or roughly days 62-64 after ovulation since it follows the LH surge by about 2 days).  There are only very rare exceptions to this rule.  As you can see, when you do progesterone testing you can narrow the due date down to within about 3 days and without testing the range is 16 days and even longer if you did multiple breedings.  The reason for the 16 day range without testing is because sperm can live for many days beyond the breeding date and fertilization can therefore take place long after the actual mating. 

People often think some pups in a litter are premature as compared to littermates due to small size or some form of underdevelopment.  Most of the time, these differences among littermates is not due to fertilzation taking place at different times, but rather due to differences in placental attachment sites.  Some pups are unlucky and the placental sites are poor, causing those embryos to be less able to receive what they need from the dam to grow normally.  Sometimes such pups are stillborn, mummified or even absorbed entirely at some point, and other times they're viable at birth but smaller and underdeveloped. 

Eggs are released from a ripened ovarian follicle within a short period of time (usually all at once, but sometimes over a period of a day or so). Once released, they take about 2 days to mature and another 2 days to reach the site where fertiliztion can happen.  If sperm are present at that time fertilization can occur, and if not present it won't (assuming sperm are able to live for days within the female, it's therefore better to breed a bit early than late).  The eggs can remain viable and ready to fertilize for only a short period of time (I don't recall exactly how long, but it's somewhere around a day or two).  So, with only rare exceptions, fertilization happens to all eggs within the same day (or so) and all pups are born between 64-66 days after the LH surge.  The variation seen between breeding dates and birth dates is due to the fact that sperm can remain viable for long periods of time.  Differences in size and development of pups is due to some pups having better placental attachments than others rather than fertilizations taking place at different times (with few exceptions).

To determine when a female is ready to whelp or whether pups are developed enough to do a c-section (or if the dam failed to go into labor and pups are going beyond normal due dates) you can do progesterone testing starting at the earliest possible whelp date.  If progesterone falls below 2 ng/mL, labor would normally begin and pups should be viable.

http://www.hilltopanimalhospital.com/IVIS.pdf  This article is a good one if you can access it.  If not, let me know and I can send it via e-mail to anyone interested.

Regards,

Diane Seaman

Edited for typos and hope I haven't missed more!

I want to clarify things a bit  to avoid having someone misinterpret things and think it's ok for their female to whelp any time between 55-70 days after a breeding.  This range is the range of POSSIBLE due dates when there are no progesterone/LH results to use in determining a more precise date.  DO NOT let a female go to day 70 thinking everything is fine!  The only time it would be ok for a female to go to day 70 is IF the breeding took place long before the female ovulated and the sperm lived long enough to still accomplish fertilization.  Even a bitch that whelps at day 70 is actually whelping 64-66 days from her LH surge, or 62-64 days from ovulation and that's important to understand.  If a female whelps at day 70, it's most likely she was bred early and the fertilization took place days later. 

A general rule of thumb to follow is to be prepared for the female to whelp a week before the first possible due date.  Start taking her temperature at least twice a day and establish what her normal temp is at those times.  Take the temp at the same time and under the same circumstances each day (if before breakfast the first day, always take before breakfast, etc.). There is usually a temp drop of about 1 degree approx 12-24 hours before labor/whelping.  When the due date is unknown to any degree of accuracy, it's wise to have a good vet aware of the situation.  There are other tools that can be used to help determine gestational age such as x-ray and ultrasound and these can also show other important info (positioning, size of whelps, viability among other things).  I've seen far more GSDs whelp too late or not go into labor at all than I have seen whelp early, so be careful not to let her go too long before involving a vet who can help you make sure all is well.  There are too many possibilities to discuss here and having a vet available is always the best thing to do for the well-being of your female and her pups (and for your peace of mind as well). 

Regards,

Diane Seaman