Aborted litter with different sizes

[Mac060709]

Hey everybody! So i have two tamuk composite rabbits, they are full sisters and each had a litter in Feb. to a californian buck. The babies were all great sizes, one mama raised four and another raised seven. The babies that died looked like normal babies and died due to natural causes it seemed. I rebred to a harlequin colored tamuk buck, and this litter was weird. They came from totally different breeders, so they shouldnt be related. The first litter seemed ok, though some babies were about a third the size of the others. After a couple days only 2 are alive and one is tiny, i dont think it will live. The other mama had a baby two days before her due date, then two days later birthed the rest of the litter. They looked like they werent fully formed, no hair and no eyes or eye slits. Some were full size and some were very tiny like the live litter. My mom owns the full sister to my does, and bred to this buck. First litter all died but second had 10 and 6 lived and are almost weaned. We have had some hot 90-95 degree days here in central texas. Any thoughts as to why these litters didnt do well? We are working at trying to keep them cooler with ice and solar powered fans. Mamas seem healthy so i dont think its listeria or bacterial related. But also dont want to rule it out if they need treatment. Our neighbor has also been spraying his field (right next to where they are kept) i assume with herbicide. He sprayed right before i bred them and again the day she had her first kit, right after she had it not right before. I hate to think its that as i try to limit our exposure but hate to think about how its affecting my familys health. My plan is to rebreed the doe who had the stillbirths to the original californian, and see if it produces another good litter. Genetic incompatibility is my best guess. Sorry for the long post, but any advice and thoughts are much appreciated!! Ive only been raising rabbits about a year now. Also, we use the same feed as my family from a local store and they havent had these issues. We use compressed timothy hay from tractor supply.

 

[eco2pia]

I think I would speculate and rule out potential issues in this order:

1. An unintentional double pregnancy caused aborted fetuses--I assume you bred all these animals at around the same time, in a controlled way (not in colony), and the buck had access just once, you didn't try test rebreeding, and the does were not exposed to another buck accidentally at some point before or after breeding...I have heard of double pregnancies with different due dates causing something like what you are describing, but it seems unlikely for that to happen for all the does unless they were housed together with a brother right before you got them and then you bred them immediately when you got them home, not aware they were already pregnant.
2. It is a heat related abortion--not likely for all does to respond simultaneously in the same way, these rabbits were bred in and bred for Texas. If this is true a late fall set of litters would be fine....a long time to wait for confirmation.
3. It is related to the spraying...but happened to a doe your mom owns, presumably some distance from the spraying. If this is true, all subsequent litters of this cross should be fine if there is no further spraying.
4. It is the buck, the genetics do not play well with these does. This to me is the likeliest scenario. You have related does, and a single buck, the does have not had problems with other bucks. If you breed back one sister to this buck, and the other to anything else at the same time, either both sisters will abort and you will know it is not the buck, or the one crossed to this buck will have a weird litter and the other will have a normal litter, and you will have an answer.
5. It is the does. This is not as likely since some of them have had good litters in the past, however genetics are not perfect probability curves or we would not see families with 5 boys or 5 girls. It is possible (but unlikely) that the does share a fatal defect and they all are prone to this type of fetal abortion about 50% of the time and you just had a lucky run the first time or something. Or it could be a combination of factors they could all be hypersensitive to heat for instance.

I think I would try the #4 solution and attempt to confirm or deny the buck's involvement.

I would also kindly ask my neighbor for the exact name of the chemical they were spraying without telling them you think it is deforming your stock, and do some research on its potential effects. If anything make them think you are looking for a recommendation. Something like "Hey was that weed killer I noticed you using last month? What kind was that? looks like it worked really well!" may get a more honest response than, "your spray killed my baby bunnies!! tell me what it is!!"

I have a friend who was alarmed by seeing a neighboring farmer apparently spraying something on their field that looked very noticeable...it turned out to be just soap suds to mark the rows for seeding. I apply insecticidal soap with a sprayer, and lime wash to fruit trees in the winter, but those are still considered organic practices. Not suggesting all farmers are innocuous, just that knowledge is power.

 

[Mac060709]

I think I would speculate and rule out potential issues in this order:

1. An unintentional double pregnancy caused aborted fetuses--I assume you bred all these animals at around the same time, in a controlled way (not in colony), and the buck had access just once, you didn't try test rebreeding, and the does were not exposed to another buck accidentally at some point before or after breeding...I have heard of double pregnancies with different due dates causing something like what you are describing, but it seems unlikely for that to happen for all the does unless they were housed together with a brother right before you got them and then you bred them immediately when you got them home, not aware they were already pregnant.
2. It is a heat related abortion--not likely for all does to respond simultaneously in the same way, these rabbits were bred in and bred for Texas. If this is true a late fall set of litters would be fine....a long time to wait for confirmation.
3. It is related to the spraying...but happened to a doe your mom owns, presumably some distance from the spraying. If this is true, all subsequent litters of this cross should be fine if there is no further spraying.
4. It is the buck, the genetics do not play well with these does. This to me is the likeliest scenario. You have related does, and a single buck, the does have not had problems with other bucks. If you breed back one sister to this buck, and the other to anything else at the same time, either both sisters will abort and you will know it is not the buck, or the one crossed to this buck will have a weird litter and the other will have a normal litter, and you will have an answer.
5. It is the does. This is not as likely since some of them have had good litters in the past, however genetics are not perfect probability curves or we would not see families with 5 boys or 5 girls. It is possible (but unlikely) that the does share a fatal defect and they all are prone to this type of fetal abortion about 50% of the time and you just had a lucky run the first time or something. Or it could be a combination of factors they could all be hypersensitive to heat for instance.

I think I would try the #4 solution and attempt to confirm or deny the buck's involvement.

I would also kindly ask my neighbor for the exact name of the chemical they were spraying without telling them you think it is deforming your stock, and do some research on its potential effects. If anything make them think you are looking for a recommendation. Something like "Hey was that weed killer I noticed you using last month? What kind was that? looks like it worked really well!" may get a more honest response than, "your spray killed my baby bunnies!! tell me what it is!!"

I have a friend who was alarmed by seeing a neighboring farmer apparently spraying something on their field that looked very noticeable...it turned out to be just soap suds to mark the rows for seeding. I apply insecticidal soap with a sprayer, and lime wash to fruit trees in the winter, but those are still considered organic practices. Not suggesting all farmers are innocuous, just that knowledge is power.

We breed them in controlled ways, they only had access to the buck for a few days then went back to their own pen. I will ask about the spray, fingers crossed its like you said and its only something harmless. Thank you for the response and advice!!

 

[Alaska Satin]

Hey everybody! So i have two tamuk composite rabbits, they are full sisters and each had a litter in Feb. to a californian buck. The babies were all great sizes, one mama raised four and another raised seven. The babies that died looked like normal babies and died due to natural causes it seemed. I rebred to a harlequin colored tamuk buck, and this litter was weird. They came from totally different breeders, so they shouldnt be related. The first litter seemed ok, though some babies were about a third the size of the others. After a couple days only 2 are alive and one is tiny, i dont think it will live. The other mama had a baby two days before her due date, then two days later birthed the rest of the litter. They looked like they werent fully formed, no hair and no eyes or eye slits. Some were full size and some were very tiny like the live litter. My mom owns the full sister to my does, and bred to this buck. First litter all died but second had 10 and 6 lived and are almost weaned. We have had some hot 90-95 degree days here in central texas. Any thoughts as to why these litters didnt do well? We are working at trying to keep them cooler with ice and solar powered fans. Mamas seem healthy so i dont think its listeria or bacterial related. But also dont want to rule it out if they need treatment. Our neighbor has also been spraying his field (right next to where they are kept) i assume with herbicide. He sprayed right before i bred them and again the day she had her first kit, right after she had it not right before. I hate to think its that as i try to limit our exposure but hate to think about how its affecting my familys health. My plan is to rebreed the doe who had the stillbirths to the original californian, and see if it produces another good litter. Genetic incompatibility is my best guess. Sorry for the long post, but any advice and thoughts are much appreciated!! Ive only been raising rabbits about a year now. Also, we use the same feed as my family from a local store and they havent had these issues. We use compressed timothy hay from tractor supply.

My first suspicions would center around the spray (depending on what it was of course), a subclinical Listeria infection, or something in their feed/hay, especially since your mother did not experience the same problems with her doe that you did with yours.

While it could be related to the buck, in my experience, when genetic lines do not match up, you'd expect things like less consistently high-quality kits, rather than developmental anomalies. The latter is usually related to inbreeding issues, and it sounds like there is no evidence to suggest that's a problem in your case.

90-95 degrees F shouldn't cause that level of disruption in gestation, especially for tamuks.

A listeria infection in the does may not be obvious before they lose the kits; oftentimes the only symptom is spontaneous abortion of deformed fetuses. It affects rabbits differently from other livestock which generally have neurological symptoms. In rabbits, the bacteria usually ends up in the blood, liver, spleen, and uterus, so it's not usually diagnosed until after loss of litter or death of the rabbit. It may be too late now, but it is usually possible to get aborted fetuses tested for the presence of the Listeria bacterium; otherwise you can have a vet take a tissue sample from the doe. Listeriosis isn't common except maybe in lab/commercial rabbits, but it's still a possibility.

Finally, even though you are using the same feed from the same store as your family, it can easily happen that you get a single tainted bag, for instance one that got wet in the corner and developed mold. Same with hay. And mold will definitely cause reproductive issues like you described. I'd do a very thorough inspection of the feed, and even examine the empty feed bags for evidence of water contact. I'd also look at the hay carefully; not only is mold a common culprit, but last year I lost both babies and adults to a bale of hay that contained lupine leaves.

 

[Mac060709]

My first suspicions would center around the spray (depending on what it was of course), a subclinical Listeria infection, or something in their feed/hay, especially since your mother did not experience the same problems with her doe that you did with yours.

While it could be related to the buck, in my experience, when genetic lines do not match up, you'd expect things like less consistently high-quality kits, rather than developmental anomalies. The latter is usually related to inbreeding issues, and it sounds like there is no evidence to suggest that's a problem in your case.

90-95 degrees F shouldn't cause that level of disruption in gestation, especially for tamuks.

A listeria infection in the does may not be obvious before they lose the kits; oftentimes the only symptom is spontaneous abortion of deformed fetuses. It affects rabbits differently from other livestock which generally have neurological symptoms. In rabbits, the bacteria usually ends up in the blood, liver, spleen, and uterus, so it's not usually diagnosed until after loss of litter or death of the rabbit. It may be too late now, but it is usually possible to get aborted fetuses tested for the presence of the Listeria bacterium; otherwise you can have a vet take a tissue sample from the doe. Listeriosis isn't common except maybe in lab/commercial rabbits, but it's still a possibility.

Finally, even though you are using the same feed from the same store as your family, it can easily happen that you get a single tainted bag, for instance one that got wet in the corner and developed mold. Same with hay. And mold will definitely cause reproductive issues like you described. I'd do a very thorough inspection of the feed, and even examine the empty feed bags for evidence of water contact. I'd also look at the hay carefully; not only is mold a common culprit, but last year I lost both babies and adults to a bale of hay that contained lupine leaves.

Thank you for the response and advice! I will definitely ask about the spray…we know he is a sales rep for fertilizer and herbicide so i assume its some sort of ag chemical. I just dont know which one specifically. We will definitely inspect all our feed and hay closely. Do you know if its expensive to get the fetuses checked for listeriosis? Would it be worth it when its unlikely in a small hobby farm setting?

 

[Alaska Satin]

Thank you for the response and advice! I will definitely ask about the spray…we know he is a sales rep for fertilizer and herbicide so i assume its some sort of ag chemical. I just dont know which one specifically. We will definitely inspect all our feed and hay closely. Do you know if its expensive to get the fetuses checked for listeriosis? Would it be worth it when its unlikely in a small hobby farm setting?

If you went to a vet it might be pricey, but never having asked for that service, I don't know. I suppose it wouldn't hurt to ask - I always prefer to know what I'm dealing with if I can.

But my first attempt would be to contact my local Extension office. They may have an option for testing that would be free or less cost-prohibitive, or might be able to direct you to a vet or lab that can provide the service. In fact they may even be able to check for pesticide/herbicide contamination - again, it wouldn't hurt to ask.

If you haven't already, I'd put the fetuses in the refrigerator and label them with both the date of birth/death and the date of storage. Some bacterial testing needs fresh tissue, other types can use refrigerated. (Some tests can even use frozen tissue, but not all, so I'd go with refrigerated.)

 

[eco2pia]

Bravo @Alaska Satin, I totally forgot to consider feed contamination! Thank you!

 

[Mac060709]

If you went to a vet it might be pricey, but never having asked for that service, I don't know. I suppose it wouldn't hurt to ask - I always prefer to know what I'm dealing with if I can.

But my first attempt would be to contact my local Extension office. They may have an option for testing that would be free or less cost-prohibitive, or might be able to direct you to a vet or lab that can provide the service. In fact they may even be able to check for pesticide/herbicide contamination - again, it wouldn't hurt to ask.

If you haven't already, I'd put the fetuses in the refrigerator and label them with both the date of birth/death and the date of storage. Some bacterial testing needs fresh tissue, other types can use refrigerated. (Some tests can even use frozen tissue, but not all, so I'd go with refrigerated.)

Ok, thank you! I used to work for a mobile large animal vet, she could possibly give me an idea on what it would cost for a test. Thank you! Yall are all so helpful!

 

[Mac060709]

Hey y’all! I just wanted to give an update on rabbits so far.

Only one baby lived, it was a normal sized one not the tiny one. Now that it’s 10 weeks old, it has lop ears which is kind of odd. I cleaned pens, feeders, and nest boxes with bleach. Ive given them herbs such as rosemary and oregano to nibble on, and acv in their water.

The neighbor would never tell us what he sprays, only that it was an herbicide but not roundup. We moved them further away sp they won’t be so close to the drift and it is blocked by a barn.

We switched hays to alfalfa as well.

I rebred the doe who lost every baby to a californian buck that produced the first good litter. She birthed 8 babies this morning, all uniform in size and completely formed. 5 lived and seem to be doing well even in the heat.

I’m wondering if the second buck that produced the bad litter has some dwarf/lop in him. I read about the peanut genes, and that is what those litters looked like with the babies being all different sizes. The lone survivor from the litter with that buck has lop ears and i have no clue where else that could have come from. Allegedly they were all full tamuks.

Thank you all for the input and help! I appreciate it so much!

 

[Alaska Satin]

Hey y’all! I just wanted to give an update on rabbits so far.

Only one baby lived, it was a normal sized one not the tiny one. Now that it’s 10 weeks old, it has lop ears which is kind of odd. I cleaned pens, feeders, and nest boxes with bleach. Ive given them herbs such as rosemary and oregano to nibble on, and acv in their water.

The neighbor would never tell us what he sprays, only that it was an herbicide but not roundup. We moved them further away sp they won’t be so close to the drift and it is blocked by a barn.

We switched hays to alfalfa as well.

I rebred the doe who lost every baby to a californian buck that produced the first good litter. She birthed 8 babies this morning, all uniform in size and completely formed. 5 lived and seem to be doing well even in the heat.

I’m wondering if the second buck that produced the bad litter has some dwarf/lop in him. I read about the peanut genes, and that is what those litters looked like with the babies being all different sizes. The lone survivor from the litter with that buck has lop ears and i have no clue where else that could have come from. Allegedly they were all full tamuks.

Thank you all for the input and help! I appreciate it so much!

The "peanut gene" you're referring to is probably the dwarf gene <dw>. It is what is called a lethal recessive, meaning that two copies of it results in a kit with a malformed and underdeveloped gut (among other things) which does not live longer than a few weeks prior to or post-kindling. These kits are called peanuts not only for their size, but also because they are shaped a lot like a peanut, with very reduced legs and hindquarters, bulbous head, bulging eyes and extremely small ears. They are half the size and about a third the weight of normal kits; they are quite distinctive looking.

There is very little chance that your litter contained peanuts, though, since a peanut needs to get a copy of the <dw> gene from each parent; that would mean that both your buck and doe would have to carry a copy. And if they were normal-sized rabbits, that's extremely unlikely, since a single copy of <dw> cause a rabbit to be a "true dwarf," which is not only smaller than normal but also has shorter ears, feet, body and head (the opposite of what TAMUK breeders are looking for).

I would say that pesticide exposure, or some other illness or stress in the doe, would be a lot more likely explanation of the range of sizes in the litter than the dwarf gene.

Since TAMUKs are a mix of breeds, it's possible that one or both of the parents could carry the lop ear gene, but it's also possible that the large ears that TAMUKs are selected for are just too heavy for your bunny to carry erect, at least temporarily. Especially in warm weather, even in non-heat-selected breeds like Satins and Champagne d'Argents, bunnies can have floppy ears for a while until they grow into them. Here's one of my 11-week-old Champagne juniors with "summer ears" (he grew into them shortly after this photo was taken):

 

[Mac060709]

The "peanut gene" you're referring to is probably the dwarf gene <dw>. It is what is called a lethal recessive, meaning that two copies of it results in a kit with a malformed and underdeveloped gut (among other things) which does not live longer than a few weeks prior to or post-kindling. These kits are called peanuts not only for their size, but also because they are shaped a lot like a peanut, with very reduced legs and hindquarters, bulbous head, bulging eyes and extremely small ears. They are half the size and about a third the weight of normal kits; they are quite distinctive looking.

There is very little chance that your litter contained peanuts, though, since a peanut needs to get a copy of the <dw> gene from each parent; that would mean that both your buck and doe would have to carry a copy. And if they were normal-sized rabbits, that's extremely unlikely, since a single copy of <dw> cause a rabbit to be a "true dwarf," which is not only smaller than normal but also has shorter ears, feet, body and head (the opposite of what TAMUK breeders are looking for).

I would say that pesticide exposure, or some other illness or stress in the doe, would be a lot more likely explanation of the range of sizes in the litter than the dwarf gene.

Since TAMUKs are a mix of breeds, it's possible that one or both of the parents could carry the lop ear gene, but it's also possible that the large ears that TAMUKs are selected for are just too heavy for your bunny to carry erect, at least temporarily. Especially in warm weather, even in non-heat-selected breeds like Satins and Champagne d'Argents, bunnies can have floppy ears for a while until they grow into them. Here's one of my 11-week-old Champagne juniors with "summer ears" (he grew into them shortly after this photo was taken):
View attachment 36317

Oh ok! Thank you for explaining the genetics, that makes sense. The baby probably just needs to grow into her ears.

I’m thankful this litter seems normal and is doing well so far! Hopefully whatever it was is fixed now and they aren’t as stressed or getting exposed to as many chemicals. Or if they had infections it seems to be better now.

Thanks for all the input and helping problem solve!