extremely small litters & most of them don't show up - why?

[hotzcatz]

For the past several years we've noticed decreased litter sizes. Also, now a lot of the litters - even when we watched and know the breeding took place - aren't even showing up at all. Anyone else have this sort of thing going on? Any ideas as to why?

We keep a herd of angora bunnies, about fifteen to twenty does and four to six bucks, although the herd numbers are down right now to 13 does (one retired from possible breeding) and four bucks (one retired from breeding). One of the bucks is a visiting buck, so he's technically not even an official part of the herd so in actuality we have only two bucks.

There were five does due on May 4th. Bred to two different bucks. This is May 6th and only one doe has had a litter and she has a litter of one with more signs of blood than usual as well. Maybe she will still have more? It was still red and fresh when I looked this morning so she had just given birth. I gave her some calf manna & BOSS and she was eating that - don't does in the middle of giving birth usually not want to eat? Maybe this will just be a litter of one. I'll check up on her again in a bit and see how's she's doing. How long does it take a doe to have the entire litter, it's usually pretty quick, isn't it?

These are English angoras and I've had them since 2009. The doe who just gave birth has had a litter before, a litter of five, so she doesn't usually have really big litters. A more or less normal sized litter is from four to six, though, these aren't that big of a rabbit. However, her last litter was five which is within the range of normal. She is now five years old, not sure how much of a factor that would be in litter size. This is her second litter, we don't breed them all that often since they're kept for their wool. The buck is not quite two and this is his first litter, although she was the third doe he'd met that day. She did stay with him for several days, though.

There were five does bred, to two different bucks and this is the only result from five possible litters. There should be about twenty babies out there! If averaging the numbers - figure one doe doesn't take and the remaining does have an average litter size of five that comes out to a lot more than just one. Anyone else experiencing this same sort of thing?

I'm suspecting it may be feed related. The herd had been on Nutrena Performance pellets which is an 18% protein pellet. I'd heard that GMO alfalfa, which has a herbicide that may affect fertility may be in the Nutrena pellets, so the herd is now eating organic alfalfa pellets augmented with calf manna, BOSS & whole wheat grains. As much alfalfa pellets as they want to eat, the manna/BOSS/grain as a side treat and lots of green forage. Primarily grasses, ti leaves and mulberry leaves. However, they'd only been started on the new diet about a week after they'd been bred, so I'm not sure how long it takes a new diet to take effect?

Another nearby rabbit breeder has noticed the same decreased litter size and lack of litters showing up and she's been feeding the same feeds. She sent an email to Nutrena and got back a response that said they relied on their growers to meet all USDA and food and safety guidelines, etc. So they don't actually know how the alfalfa was grown. GMO alfalfa was approved for use in 2011, I think it was.

It had been a year since the previous litter and that had also been a litter of one. The two year old buck came back for some vacation bunny sitting and it's okay with the owners for him to meet the girls. He'd been on an entirely different pellet, Purina Pet Rabbit pellets and he's still on those pellets. So, perhaps the Nutrena Performance is suspect? What else could it be? Anyone else have any ideas?

At the moment, the plan is to rebreed all the does who didn't have a litter and keep them on the new diet and see if it makes a difference if they're on the new diet for the entire pregnancy.

 

[alforddm]

How long are you going between litters?

 

[MaggieJ]

I can't pin the cause(s) down for you, but some things I'd be considering are the ages of the does, the length of time between breedings, excessive heat and diet. Diet can affect both does and bucks, heat can cause (usually) temporary sterility in the bucks, and both age and large gaps between breedings can allow does to accumulate fat in the body cavity that makes it difficult to conceive.

 

[hotzcatz]

Day One litter of five English angoras

Day Two of baby bunnies​

It took her until the early afternoon, but she finally had a litter of five. Yay! Hopefully the new organic diet made a difference and that will solve the problems, although the other four does who were supposed to also have litters, didn't.

This is the first litter we've had since November 29th which was a litter of three, which is a small litter. But the mom never made milk for them so they didn't make it.

The litter before that one had been a litter of one on October 25th. In the past twelve months, we've had 26 matings and the only results have been the litter of one, the three which didn't make it and now this litter of five which was on an organic diet starting halfway through the doe's pregnancy.

The 26 matings were between 4 different bucks and 11 different does, with ages anywhere from six months old to four years old.

Here's the numbers from my database, starting in 2010, when we had the first bunnies. From what I've read, the method of spraying the alfalfa fields with an herbicide to 'ripen' the field all at the same time started in 2011, although I don't know how long it would take before it became a common process. The feed mill wasn't able to tell me the specifics of how the alfalfa that they use for their feed was grown and harvested.

In 2010, 5 matings, 4 litters, 17 babies. ( 4.25 per litter, 80% fertility rate)
In 2011 - 26 matings, 16 litters, 69 babies (4.31 per litter, 61% fertility rate )
In 2012 - 23 matings, 13 litters, 82 babies ( 6.3 per litter, 56% fertility rate )
In 2013 - 6 matings, 2 litters, 11 babies ( 5.5 per litter, 33% fertility rate )
In 2014 - 14 matings, 4 litters, 25 babies (6.25 per litter, 28% fertility rate )
In 2015 - 15 matings, 5 litters, 23 babies ( 4.6 per litter, 33% fertility rate )
In 2016 - 24 matings, 8 litters, 32 babies ( 4 per litter, 33% fertility rate )
In 2017 - 9 matings, 1 litter, 5 babies (5 per litter, 11% fertility rate )

I've bred three does with three different bucks and we will see if litters appear on June 7th. Two of the bucks have been on the new diet since April 18th. The buck who is the sire of the current litter is still eating the pellets he came with, which is a different brand than the Nutrena Performance Rabbit 18% pellets the herd here had been eating.

Two of the does had been eating the Nutrena pellets until they were bred, now they're on the organic diet. One of the three does has been on the organic diet since it started in mid-April. Later today, I'll try breeding two more does who have been on the organic diet and see if it makes a difference.

The ages of the bucks are: Gomez: 1 year 8 months, Phineus Phogge: 1 year 1 month, Sydney: 3 years 1 month and maybe we will give the retired Dozer (7 years 3 months old) buck a shot at it, but it's possibly beyond his abilities anymore. He's been eating the suspect feed, though, since I'd just gotten 100# of it before deciding the issue may be feed related and it's been fed to the wooler herd. The bred does are Gayle: 6 months, Jessie: 1 year 9 months and Sirocco: 1 year. Much younger does, but that shouldn't be a problem.

 

[alforddm]

I'm wondering if your not breeding frequently enough to keep fertility up. If I'm remembering correctly 4 litters per doe per yr is the recommended minimum. Older does tend to accumulate internal fat even if they don't appear overweight. The internal fat makes conception hard and tends to lead to small litters with large kits.

It could also be feed storage time issue. If you feed is staying in storage for an extended amount of time (possible if they have to ship from the mainland). It maybe old before you even get it. This could defiantly lead to decreased performance and given the humid nature of Hawaii, mold toxins are also a possibility even if it isn't visible to the eye.

Congratulations on the litter. I hope you get the issues solved soon.

 

[Marinea]

I noticed you stated you feed "as much alfalfa pellets as they want to eat". I wonder if that might be part of the problem.

My does are need 2-3 times a year, and I almost never have misses, but I have strict pellet rations. My buns get lots of greens and hay, but a set amount of pellets daily. I am wondering if you have an internal fat issue.

 

[hotzcatz]

I'm wondering if your not breeding frequently enough to keep fertility up. If I'm remembering correctly 4 litters per doe per yr is the recommended minimum. Older does tend to accumulate internal fat even if they don't appear overweight. The internal fat makes conception hard and tends to lead to small litters with large kits.

It could also be feed storage time issue. If you feed is staying in storage for an extended amount of time (possible if they have to ship from the mainland). It maybe old before you even get it. This could defiantly lead to decreased performance and given the humid nature of Hawaii, mold toxins are also a possibility even if it isn't visible to the eye.

Congratulations on the litter. I hope you get the issues solved soon.

The bunnies here aren't bred real frequently at all. They're angoras so they're not sold as meat bunnies. We're never gonna meet the recommended minimum, maybe that's partly why smaller litters. The doe who just had the litter of five is five years old and this is her second litter. She may have one more litter and then be retired.

I'll go look at the database and figure out how many litters which does have had, but I doubt any of them have had more than one or two litters per year at the most.

Yeah, we've gotten moldy feed from the feed store before. Now we've switched to a larger feed store than brings in feed more frequently. <br /><br /> -- Tue May 09, 2017 6:24 pm -- <br /><br />

I noticed you stated you feed "as much alfalfa pellets as they want to eat". I wonder if that might be part of the problem.

My does are need 2-3 times a year, and I almost never have misses, but I have strict pellet rations. My buns get lots of greens and hay, but a set amount of pellets daily. I am wondering if you have an internal fat issue.

They don't like the organic alfalfa pellets as much as they did the rabbit pellets so they don't eat all that much of it. Given a choice between ti leaves and rabbit pellets, they'd choose the rabbit pellets. Given a choice between ti leaves and organic alfalfa pellets, they choose the ti leaves. I'm hoping they will gain some weight, they're all at the low end of the breed standard. I weighed them all several days ago and will weigh them all again next week to see if they're gaining weight on the new organic pellets.

Usually I go by how bony they feel. If I can feel the knobs on their backbone and ribs, then they need more feed. Since the does are all kept in a big communal hutch, when I was feeding restricted pellets, there'd be some who'd not get enough to eat since the others would eat it all. If they were bony, they'd get taken out of the communal hutch and put over by themselves and fed more until they were back into condition. But if they were put back in with the herd, they'd lose condition again. It was a lot easier to just feed the herd enough that even the shy ones get enough to eat. For the breeding does, they're usually by themselves in a breeder space so then their diet can be regulated if necessary.

 

[alforddm]

The bunnies here aren't bred real frequently at all. They're angoras so they're not sold as meat bunnies. We're never gonna meet the recommended minimum, maybe that's partly why smaller litters.

In this situation, you may have better results breeding one or two of your best does more frequently and not breeding the others. You'd still get the same number of litters but it could potentially help with your fertility issues.

It would be an easy theory to test in any case.

 

[hotzcatz]

It would be easy to test after litters start showing up again. When there's only one or two litters from over twenty breedings, then I figure it's something other than the rabbits themselves that's the problem. I think it's been the feed, we've got one litter now since switching to the new feed. There's four more does bred and due on June 6th - 8th, so we will see if diet makes more of a difference. I didn't rebreed the doe who had the litter. She's five years old and having babies to feed is enough stress on her. She's taking care of them like a champ, though, and she's one of the bigger rabbits, so I'll keep the best buck from this litter. What with the lack of litters lately and a mishap when we had a house sitter, I'm down to only one viable buck that is actually mine. There's two visiting for a few months, though, so that will give me time to breed a few more bucks for the herd, hopefully.

The best does do get bred more, although I've been selecting them more to towards keeping them from being inbred. Which means after they have a litter, then they don't always get rebred right away. I have a very small gene pool (eight original rabbits, three of whom were bucks) and a very difficult time getting in more genetic material to work with. It's getting a bit better now that we're on fourth and occasionally fifth generation.

I think I'll start selecting them for litter size as well as wool quality. I'm going to start selecting larger rabbits, but that still won't be one of the top three criteria. Wool texture, crimp, color, mothering ability, size of rabbit and size of litters, I guess? <br /><br /> -- Wed Feb 06, 2019 2:11 am -- <br /><br /> 2019 Update on this thread

We're finally getting a handle on rabbit fertility, I think. There were only four litters last year (2018) since all we had were the older rabbits to work with. Of the four litters, all the offspring were all bucks except for two females. Lousy ratio when I needed young does for breeding!

Litters in 2018
1. litter of two, both bucks
2. litter of three, one lost at a day old, remaining two were both bucks
3. litter of four, but doe didn't make milk and lost entire litter
4. litter of five, had to hand feed for three days until doe made milk but litter survived, 3 bucks, 2 does.

So far this year, early Feb, 2019, we've had these results:
1. Young doe (4.5 months) to young buck (4.5 months) = a litter of eight. Although the doe didn't make milk so the litter was lost. This was a brother/sister litter because we'd made a mistake on gender and kept them together as young adults. I'd not expected them to be functional at that young and it wasn't an intentional litter.
2. Breeding older doe (3.5 years) to a young buck (9 months)= a litter of four.

There's three upcoming litters due in early March:
3. Caesar (10 months old buck) x Olivia (5 and a half month old doe). She's just barely old enough, but this is somewhat of an experiment
4. Phineus (2 years 10 month old buck) x Suzie (3 years 6 month old doe). This is a 'control' breeding to see if an older pair will have a litter and how big it will be. Plus they are the best two and I really want a litter from them.
5. Augustus (10 month old buck) x Cassandra (7 month old doe). This is probably about the right age they should have their first litters?

So we're still gathering data on breeding at different ages.

Also, with this group of rabbits, the older ones may have had Vent disease. We did give a round of penicillin shots last year (one shot each week for five weeks in a row) http://hillsidefarmhawaii.com/blog/2018/20180322.html and started getting litters afterwards. Since we had the one litter of an older doe with younger buck, it may be Vent disease has decreased buck fertility? As mentioned, I'm still gathering data.