Is this true? A way to tell if a doe is pregnant...

[jimmywalt]

My wife was reading online last night about how to tell if a doe is pregnant (not this website, but some Google search). It said that on or around day 15 take something from a bucks cage (resting board, etc) and put it in the does. If she rubs her neck on it then she's not pregnant. If she seems to be upset with it or growls at it then she is pregnant.

So we tried it with a MiniRex that we really aren't sure if she's pregnant or not. Last night was day 19 for her. We took a resting board from a bucks cage (not the one that she was bred with) and put it in hers. She started rubbing her neck on it like the website said.......... So now we assume she's not pregnant (and she doesn't look it either).

We aren't any good at "feeling" for the kits on day 15, so that won't work.

So have any of you ever heard of this method for determining pregnancy? It would be a great tool if it's true!

Thank you!

 

[SA Farm]

I've heard of a similar idea - just take the doe to the buck and if she gets upset at him/won't breed, chances are she's pregnant. Downside is, there's the occasional doe that will take the buck and then you've got two litters...
Since rubbing the chin on an object is a rabbit's way to mark territory, I would think that a pregnant doe would mark any new territory that came into her realm. I have an indoor rabbit that will pretty much growl at/attack any new object that comes into her cage (except people oddly enough) whether she's pregnant or not. So while, yes, I think it is possible for that trick to work, it wouldn't necessarily work for all does.

 

[MamaSheepdog]

I have never heard of that, and as SA said, chin rubbing is a way of marking territory and claiming items as their own.

just take the doe to the buck and if she gets upset at him/won't breed, chances are she's pregnant. Downside is, there's the occasional doe that will take the buck and then you've got two litters...

Actually, does most commonly will accept the buck about half way through gestation when they are pregnant. However, they cannot get pregnant twice.

In most mammals the progesterone secreted during gestation inhibits oestrus and the pregnant female refuses to mate, but a pregnant doe may accept mating throughout the gestation period. Indeed, in the second half of pregnancy this is the most common behaviour (Figure 10).

A breeder cannot therefore use the sexual behaviour of does as an indication of pregnancy. Mating occurring during gestation has no dire consequences for the embryos. Unlike the phenomenon observed in the female hare, superfoetation (two simultaneous pregnancies at two different stages of development) never occurs in rabbits.

http://www.fao.org/docrep/t1690E/t1690e05.htm

 

[SA Farm]

Well, I've seen it happen, so I don't believe the study. I believe that their study is correct based on the rabbits they tested/heard of, but of all the thousands of rabbit breeders out there, I'm sure not all of them share all the strange/unusual things they've seen and heard with their rabbits.
The way I understand it (from how my Dad explained it to me since that's the method he/we used to see if a doe was bred when I was a kid) is that in the first breeding only one ovary became fertilized. In the second breeding two weeks later, the other ovary was fertilized. The doe had two kindlings of 6 and 4 in one month. I know it's incredibly rare, but I know it can happen The doe was a NZ/FG and all the kits survived.

 

[jimmywalt]

Well, I've seen it happen, so I don't believe the study. I believe that their study is correct based on the rabbits they tested/heard of, but of all the thousands of rabbit breeders out there, I'm sure not all of them share all the strange/unusual things they've seen and heard with their rabbits.
The way I understand it (from how my Dad explained it to me since that's the method he/we used to see if a doe was bred when I was a kid) is that in the first breeding only one ovary became fertilized. In the second breeding two weeks later, the other ovary was fertilized. The doe had two kindlings of 6 and 4 in one month. I know it's incredibly rare, but I know it can happen The doe was a NZ/FG and all the kits survived.

My wife told me about this too!!!!!!!!!!!!!!! So while it's rare, I bet it can happen.......... but I don't want to find out first hand.

 

[MamaSheepdog]

Well, I've seen it happen, so I don't believe the study. I believe that their study is correct based on the rabbits they tested/heard of, but of all the thousands of rabbit breeders out there, I'm sure not all of them share all the strange/unusual things they've seen and heard with their rabbits.

Some of our members have had does deliver a kit or kits one day and then have more several days later. How long was it between litters for the doe?

It is possible that the doe had two uteri (uteruses), a condition known as Uterine Didelphys. I have no idea if it would be possible to carry two pregnancies of different gestational age in each one. :?

http://www.medicinenet.com/script/main/ ... ekey=77686

http://en.wikipedia.org/wiki/Uterus_didelphys

The way I understand it (from how my Dad explained it to me since that's the method he/we used to see if a doe was bred when I was a kid) is that in the first breeding only one ovary became fertilized.

*Edit: If that was the case, human women would often have pregnancies of differing gestational age, since typically we release an egg from only one ovary at a time.

In multiparous animals (those that have litters), it is normal for both ovaries to release eggs at the same time. This rarely occurs in uniparous animals as well.

I do Artificial Insemination of equines, working with horses and donkeys. We ultrasound the ovaries to monitor follicle size on the ovaries to determine when to inseminate them. We have had a couple of mares and several donkeys release eggs from both ovaries.

Unfortunately, in horses twin births have very poor outcomes if they reach the end of term. Therefore it is routine to "pinch" and kill one of the embryos early in gestation. Sadly, often the other embryo will also die when this is done.

In the second breeding two weeks later, the other ovary was fertilized.

According to what I learned at UCDavis during my course on Artificial Insemination, it just isn't possible. The information below (copied from a prior post) explains the hormonal changes that occur when an animal becomes pregnant:

I'm about to get technical on you, :explanation: but am trying to keep it relatively simple, so here goes:

When the eggs are released from the ovary, the follicle is called a corpus hemorrhagicum, but the cells change to become a corpus luteum. The corpus luteum produces relatively high levels of progesterone and moderate levels of other hormones such as estrogen to inhibit further production of follicle stimulating hormones, preventing the growth of new follicles and release of eggs.

The corpus luteum remains in the ovary while the eggs traverse the fallopian tubes, continuing to secrete progesterone to prepare the uterus for implantation of the embryo(s). When the egg implants itself, it releases another hormone (HCG) which signals the corpus luteum to continue secreting progesterone to maintain the thick lining and increased blood vessels to the uterus to maintain growth of the embryos. Eventually, the placenta takes over and the corpus luteum degrades.

If the eggs are not fertilized and implantation fails to occur, the corpus luteum stops progesterone production and decays, allowing the receptive cycle to resume.


post223088.html

 

[user 3309]

I saw one video that the fur comes out easily when lightly pulled, but that could be the right timing when they are molting too.

 

[SA Farm]

The litters were consistent with the two times she was with the buck
Animals are pretty amazing and flummox scientific fact constantly :lol: Mules aren't supposed to be able to reproduce at all, yet there are documented cases of it occurring... Just because it's not supposed to be possible, doesn't mean that it isn't

 

[Dood]

According to what I learned at UCDavis during my course on Artificial Insemination, it just isn't possible.

However, rabbits are rather unique in that they are induced ovulators and do not follow the typical hormone cycle of the next mature eggs rupturing and inhibiting the others but instead the stimulus of sex triggers ripening and ovulation of multiple ovum.

I have had 3 does have "odd" deliveries and believe two litters conceived at different times was the cause but never with a 14 day delay, the longest was 4 days.

 

[MamaSheepdog]

According to what I learned at UCDavis during my course on Artificial Insemination, it just isn't possible.

However, rabbits are rather unique in that they are induced ovulators and do not follow the typical hormone cycle of the next mature eggs rupturing and inhibiting the others but instead the stimulus of sex triggers ripening and ovulation of multiple ovum.

Yes, they are induced ovulators, but the follicles develop in "waves" so only a certain number are mature enough to rupture at any given time... next time you butcher a doe look at her ovaries and you will see the follicles of varying sizes.

As soon as the eggs are released the ruptured follicles begin to change into corpus luteum.


Corpora lutea are ephemeral endocrine glands occurring in all vertebrate groups. These structures develop in the ovaries after ovulation, from the membranes of postovulatory follicles. Luteinization of the cells lining the follicular cavity is accompanied by a striking increase in progesterone secretion. Progesterone is the hormone required for the establishment of pregnancy, and the main function of the mammalian corpus luteum is to synthesize and secrete this steroid.

http://link.springer.com/chapter/10.100 ... 3-1869-9_9

The transformation of the follicle into the corpus luteum is an important turning point in the diphasic menstrual cycle of women and in the ovarian cycles of other mammals, from which the human cycle evolved. Progesterone prepares the uterus for the implantation of fertilized eggs, and it is also needed for the maintenance of pregnancy once implantation has taken place. It evokes a reduction in the ability of the uterine walls to contract, a proliferation of the glands of the endometrium, and the formation of glycogen. In addition, through its feedback action upon pituitary secretion, progesterone inhibits further ovulation, thus ensuring undisturbed fetal development.

http://physrev.physiology.org/content/80/1/1

I did a bit more research, and found that in rabbits the placenta does not "take over" for the corpus luteum after all, but the CL must remain active throughout the gestation period.

The rabbit is among those species in which the placenta secretes low or physiologically insignificant quantities of progesterone, and therefore, the corpora lutea must remain steroidogenically active throughout gestation (Hilliard, 1973; Thau and Lanman, 1974). If the young embryo is to survive, it must transmit a signal that in some way halts or overrides incipient luteal regression, reflected in declining serum progesterone values by 15 days after ovulation in non-pregnant animals (Keyes et al., 1983a).

http://link.springer.com/chapter/10.100 ... -5395-9_17

 

[PSFAngoras]

Two weeks ago I put a doe back in with a buck because I felt nothing while palpitating and she readily accepted him. In the last week, she's been nesting, and is pulling fur as I write for a litter that was from the first breeding. In other words, it's not always likely that the buck or his smell will upset her while she's pregnant.

The best way to tell is to learn to palpitate. I didn't feel anything two weeks ago in this doe since she's a first timer and has a very tight abdominal wall, but I could feel the kits this last week as they started to move into position, one even kicked me! There is a very informative article on the ARBA site about palpitation, I tried many times before reading it to palpitate and never did do it correctly, but after reading the article it was one of those 'ah-ha' moments. I'll see if I can't find he link for you. <br /><br /> -- Thu Jul 31, 2014 10:13 pm -- <br /><br /> https://www.arba.net/PDFs/palpation.pdf

It's easier to start with a doe that's had a few litters as their abdominal muscles aren't usually as tight, but there have been a few first timers that I've been able to palpitate.

 

[hucklekree]

This all sounds better than what I usually do which is put the does in with the buck and then wait for 31 days! :lol: Not very efficient. But I'm horrible at palpitating and don't want to chance two different pregnancies (even if it isn't possible). I have heard of the board/buck item in cage theory but I agree that a doe is going to pretty much rub anything with another rabbit's scent on it put into her territory. But eh :roll: I don't have the most experience.

 

[skysthelimit]

I too was always under the impression that the hormone that maintains the proper environment for embryo development suppresses the release of more eggs. The environment needed to mature eggs, is not the same as the environment needed to grow an embryo, they are total opposites. Once the uterus is in use, it's sealed from receiving additional eggs, even if, those eggs would not be in the proper environment to mature. Since the eggs mature even if they are not fertilized, it's possible to have babies at different stages of development in one pregnancy.
It's also possible for babies to have unfavorable spots of attachment to the walls, and have unequal fetal nourishment and development. It's also possible to not completely expel both uterine horns in one session, if contractions are weak, the animal is startled or some other issue occurs.

Once the kindling process begins, I've never had any kit live who wasn't born with the rest of the group, but I had a very difficult birth with a doe that took four days to expel all the kits.

That makes it important to learn to palpate, not just for pregnancy checking, but to know when all of the kits are out of the uterus.