Mena's First Litter

Setting up electronic calendars with reminders is really important, if you're scatter-brained like me, sometimes.  I had it in my head that Mena was supposed to get her nest box on the 25th, according to my Evan's Software (which I had set the "nest in" date to 27 days after breeding).  Since I had it in my head that the 25th was day 27, I didn't feel too bad about not getting the box in until the 26th.  Then I looked at my Evans Breeding List...the 25th was the day she was due  (set to 30 days after breeding).  Oops!  So I rushed out to double check on her.

Mena's nested cage.

The nest box looked undisturbed, but she had fur and piles of straw all over her cage, but no signs of kits or a birth.  It looked like one of two things had happened: 1) she had kindled on the wire and managed to clean it all up, building a nice nest for kits, and the kits had all crawled out (I don't have baby-saver wire); or 2) she still had yet to kindle.  Still, I pulled the nest box toward me.  No fur, all the straw still lying exactly like I usually stuff the box.  I shoved my fist into the back of the nest box.  Wiggly warmth!

Virtually undisturbed nest.

I couldn't believe it!  Seriously, the nest looked like it hadn't been disturbed at all.  So I brought the box in to do a head count and health check.

Litter of kits buried way in the back of a nest box.

Buried way in the back, under layers of straw, I found 6 kits, all full-tummied and wiggly.  Seriously, these were some of the most fidgety kits I've ever handled!

Litter of newborn black and blue otter and self rex.

Sadly, my hopes for chocolate otters seem to have failed. Of the six, two are blue otter, two are black, one is a black otter, and one is a blue. I think that only one is a doe, too (one of the blue otters). Oh well, more to sell, I guess!

Sexing Rabbits

I did a quick Google search to see if there was a good reference for people new to rabbits on how to sex a rabbit.  To my surprise, none of the results on the first page seemed like good references; they either seemed to provide an overload of information or only gave general information and not-so-helpful diagrams.  So, my remedy is to provide one here.  Please feel free to share this post around if you find it helpful.

Mature rabbits are by far the easiest to sex.  However, as you can see from the above picture, simply looking at the vent--that's the term we use to refer to all rabbits' private areas, including the anus and vulva or penis--is not enough to determine sex.

Scrotum on a mature buck.

Many mature bucks have very obvious scrota when you flip them over.  Sometimes, especially when it's cold or the buck is stressed out, they suck their testicles inside their bodies, leaving only the scrota external, often hidden in the fur around them.  If you look near the vent, you may be able to find areas of loose flesh, which are the scrota.  Do not mistake a bald area for a scrotum, though--many does will have a bald area in the same place as you would find testicles, but the flesh will be more firm, rather than an empty(ish) sac.

However, a buck that has been neutered, or a buck which hasn't matured to the point of his testicles descending, is still indeterminable from a doe unless you actually expose the vent.  To do this, you'll first have to flip the rabbit over.

Once you have the rabbit on its back, use your free hand to expose the vent.  One finger (or your thumb) should be on the tail, and another finger (or your thumb) should be on the furry mound, such that your fingers frame the vent.

Finger on tail, thumb on mound to frame rabbit's vent.

The anus is the slit that has fur.
The mound is a raised area of fur,
opposite the tail.

With your fingers framing the vent, push the tail gently away from the vent, and press gently into the mound. This will make the genitals pop out so you can see if it is a penis or vulva.

Mature doe - note the slit and
close proximity to the anus

Mature buck - note the pointed-cylindrical protrusion
and distance from the anus.

With younger rabbits it can be a bit trickier.  Not only are they smaller, but their hormones haven't kicked in to bring their genitals into their final form.  As such, it can be very easy to over- or under-expose the genitals, making them look like one gender when they're really the other.  I find that it is best that the tail-holding finger only holds the tail in place, without pulling back on it, and the mound-pressing finger presses gently down into the belly and slightly toward the vent, until a shape becomes apparent.  You may have to readjust your finger placement until you can get it to pop definitively.

5-week-old doe: slit very near anus

5-week-old buck: tube protrusion slightly away from anus

3-week-old buck: tube protrusion slightly away from anus

3-week-old doe: slit very near anus

5-week-old buck slightly overstretched,
looking like a slit, but still very far
from anus.

3-week-old buck very overstretched,
looking like a slit, but note the gap
between the slit and the anus.

Many people are unable to sex kits under 6-8 weeks old, so don't worry if you have a hard time: you're not the only one! Just keep practicing.

It is also possible to sex kits that are only a day or two old! (click to read that article)

State of the Rabbitry Address

When last I updated everyone on my rabbits, Lisi's and Chesna's litters were just hitting two weeks old, and Sweetie and Aster had just kindled nine kits each.  I am happy to say that all kits have survived.  (I really hadn't been sure that Sweetie and Aster would be able to handle such large litters, since many does can't handle more than 7 or 8, especially since Sweetie's last litter was only two kits).

Sweetie's litter explores the nestbox and beyond at 19-days.

As of today, all nest boxes have been removed (the younger litters are just short of three weeks old, but hopping in and out of the boxes frequently, and I'd rather have them all hopping around the cage than risk one getting stuck out of the box and getting chilled--temperatures are still dropping into the low thirties over night).

Even the youngest of kits are starting to nibble on pellets in the feeder, and are starting to get curious about drinking from the bottle.  Of course, they still try to sneak a few drinks off mom, too.

19-day-old kits eating pellets

Kits learning to drink.

Kit stealing a drink off mom.

Of course, the older kits have got it all down pat. At exactly one month old, they're of an age where many commercial rabbitries would consider weaning them. However, a number of studies have concluded that weaning before 5-6 weeks results in notably less growth, and also puts the kits at a higher risk of weaning enteritis, which is often deadly. Over the next month, I should see an accelerated growth rate from them as they eat more and more while still getting nutrition from their mother's milk.

8 one-month-old Californian kits pile at the feeder.

Month-old Californian kit drinks from water bottle.

Trudy enjoying attention at an Easter Egg Hunt.
(Image taken by The Observer)

In addition to the progress of the current kits, we have a lot of expectant mothers, now.  Mena will get her nest box in a couple days.  Californians Lavender and Laurel; New Zealand Iza; and Rex Mosaic, Princess, and Godiva were all bred on one day.  The goal with the Californians and New Zealands is to have market litters available for nearby counties.  Trudy has been difficult about breeding, but a trip to a nearby Easter Egg Hunt changed her mind (roadtrips can do that to rabbits for some reason, and she really enjoyed all the extra attention).

Another fun happening was that I managed to sell all of my extra bags of manure for about $100!  My "shit list," as some people are referring to it, is now back-ordered.

Working with Two or More Genes

We covered the basics of genetics last week.   Rabbit colors are determined by no fewer than five genes, though.  To expand from doing simple, one-gene Punnett squares to two or more genes is fairly simple, although it may take some practice for some people.

With a single gene, Punnett squares are 2x2 (plus labels).  For two genes, it becomes 4x4.  Three is 8x8, and so on.  However, it's not as complicated as you might think.  To fill out a two-gene Punnett square, set up the 4x4 grid.  Focus on one gene-series at a time.  Say that you're working with a rabbit that is Aa for the first gene-series you're working with.  Write each gene, separately, as a label for each of the first two columns.  Then, write them again,  in the same order as labels for the last two columns.  For the second set of genes (we'll say that they're Bb), write the first gene as the label for the first two columns, and the second gene for the last two columns.  If both parents are AaBb, you should get something that looks about like this:

From there, it's just a matter of combining the labels.  The first square gets A from the top, A from the side, B from the top, and B from the side.  Continue filling out each square until they're all full. Remember that capital letters are usually written before lower-case, to show which trait the offspring will show. You should end up with something like this:

If you're good with patterns, you may notice that the Punnett square you would have gotten from the first set of genes (As) is repeated four times.  Zoom out your focus and you notice that the second set of genes makes a Punnet square, where each square is a quadrant on the combined square.  (Sorry for getting technically-termed on you...I'm not really sure how else to say it.)

A second method is to make a Punnet square for the first gene-series (the As). Thus:

Then, copy it until you have a new 2x2 grid made up of those:

You have now set yourself up to do a Punnet square for the next set of genes.  Put parent #1's first gene of that series over the left-most column of squares, and the second gene over the rightmost.  Do the same with the second parent's genes for upper and lower rows.

Then complete the larger Punnet (for the second gene) by filling each of the four smaller squares within each set with the same combo.

The end result is the same as before.

If you wanted to further expand to a third gene, you would copy this Punnett square to make the next one for the third gene.  For a fourth gene, use the third compound Punnett.  Repeat ad nauseam.

Once you have your compounded Punnett square, you can list all potential genotypes.  For the two-gene set, you have:

• AABB (1 in 16)
• AaBB (2 in 16)
• AABb (2 in 16)
• AaBb (4 in 16)
• aaBB (1 in 16)
• aaBb (2 in 16)
• AAbb (1 in 16)
• Aabb (2 in 16)
• aabb (1 in 16)

To see the list, you might just want to read through the squares, and tally if you come across a repeat.

To get the phenotypes, look at the most dominant trait for each letter.  You should get:

• A-B- (AABB, AaBB, AABb, AaBb = 9 in 16)
• aaB- (aaBB, aaBb = 3 in 16)
• A-bb (AAbb, Aabb = 3 in 16)
• aabb (only aabb = 1 in 16)

I know all of this may be hard to grasp, especially for those who have a hard time with patterns or math, so I promise I will make a worksheet to go along with this before much longer.  In the meantime, grab a piece of scrap paper, draw a few squares, and try out a few different combinations: AABb x AaBB, aaBB x Aabb, etc.  Have fun!  (Oh, and feel free to email me if you want me to check your work.)

Topics still to cover: simplifying Punnett squares for homozygosity, exceptions to simple inheritance, and specifics of rabbit colors.

Kit Development in the First Weeks

Kits change from newborn to 5 days old.

Rabbits are born blind, deaf, and furless (although some may have hints of peach fuzz).  By five days old, their ears are starting to open up, and they'll be completely open by a week old.

7-day-old Californian kits have open ears.

13-day-old New Zealand kit already starting to pose.

Their eyes can start to open up as early as nine days, and most will have their eyes open by 12 days old.  They may open one eye and then another, and you may even see the eye when it's still only partially open.  That's normal.  If the eye still isn't open at a full two-weeks old, you can try to open it, gently.

Eye on 12-day-old kit not completely opened.

Watching Birth

I was treated to something very uncommon, even among people who have been raising rabbits for decades.  I got to watch the end of a rabbit birth!  Remember:  I've been around breeding rabbits since the early 90s, and raising them, myself, since the late 90s.  This is only the second litter I've had the pleasure to watch, and the first where I actually had a good enough angle to actually watch the birth.  (The last one, all I saw was the doe's back twitching as she stood over her nest in the box, and then her eating some of the afterbirth before hopping out).  Sweetie gave birth about 4:15 in the afternoon.  (The previous litter I watched was about 6:30 in the afternoon, in early June).  Most rabbits give birth in the middle of the night, and seem to be able to purposefully postpone labor to avoid giving birth when people are around, which is why seeing a birth is so rare.

The video is fairly long, but most of it is just her cleaning the kits off, which is interesting in its own right. If you skip to the end, you can see the whole litter.  There are nine of them!

This happened the afternoon after discovering that Aster had had a litter of nine, herself, overnight. I say 18 babies in one day is quite good.

Unfortunately, it appears that Godiva and Princess are not going to have their litters.  I had high hopes for Godiva, since she actually built a nest and pulled some fur the day I gave her a box, but then she destroyed the nest, and shows no signs of producing kits.  She had presented well for Tron, same as Mena, who also failed to produce.  This may indicate that Tron is infertile, which upsets me terribly. I'll probably still try breeding Godiva back to Tron (I really want chocolate otters), but if Mena doesn't kindle from her latest breeding (I bred her back after she had passed 35 days without kindling), then I will probably rebreed both of them to another buck.

Princess is getting fairly old, and Ixis, who I bred her to, is about two years, himself, and hasn't sired a litter yet (my own fault for forgetting to plan does to breed to him--Princess was his first breeding).  I'm not really sure who may be at fault in their case.  I was hoping to get opals from them (both of them carry blue, and I suspect that Ixis is probably castor under his white coat), but I may resort to my regular pairing of Princess with Chip for otters and selfs.

Sexing At 12 Days

Once upon a time, I could sex kits reliably at 10 days old.  These days, I'm not as good, but maybe with practice I can get it down again.  You may remember that I sexed Chesna's and Lisi's litters at 1 day old.  Let's see how I'm doing (if I'm sexing right at the 12-day mark).

Z1: Day 1 thought "Doe?" Day 12 looks to be buck

Z2: Day 1 thought "Buck?"  Day 12 looks ambiguous

Z3: Day 1 thought "Buck?" Day 12 definitely doe.

C1: Day 1 thought "Doe?" Day 12 ambiguous

C4: Day 1 thought "Buck" Day 12 leaning toward doe

C6: Day 1 thought "Buck". Day 12 looks like doe.

C7: Day 1 thought "Buck". Day 12 looks ambiguous.

C8: Day 1 thought "Buck?". Day 12 looks like doe.

Cs 2, 3, 5 may have gotten mixed up.
Originally thought all bucks.
Day 12, looks like 1 doe, 2 bucks.

OK, so I guess I'm still working on it.  On some of the obvious day 12s that don't match the original guess, I can see where I was wrong.  We'll check again another week to see if we're getting any better.  This just goes to show how difficult sexing kits can be--I've been doing this for 15 years, and I still have problems.

In case you're wondering about why I try to sex so early, I do this so that I can confirm sales and availability to buyers as soon as possible.  Many people cite that "something can happen," but I've very rarely lost kits after 9 days old, and I can usually tell by day 3 which ones are likely to die.  By "rarely" I mean I can count the number of kits lost at those ages on one hand.  So, my thinking is that the younger I can accurately determine sex, the sooner I can confirm availability for interested buyers.  I still won't sell the kits until they're 8 weeks old, but if I can give the buyers a month heads up that I do indeed have the rabbits they want, then that gives the buyers a month to prepare.

I also took a video of sexing kits at this age to demonstrate just how difficult it can be.  I'll upload it, soon, but right now my internet connection is just a bit slow.