More Genetic Selection Stuff

Okay, continuing with heritability of traits, here is a chart that actually breaks down each individual component of an Angora coat to determine the heritability of each separate characteristic (I realize this is a little in-depth for even the most neurotic among us, LOL, but it's definitely interesting information:)). This chart is also taken from the 'Rabbit Production' book on pg. 334 (8th Edition):

Trait--- % Heritability

Wool Yield: 1st and 2nd harvest 0.20-0.23
1st thru 5th harvest 0.19-0.33
3rd or later harvest 0.23

Wool Characteristics:

Back bristle length 0.25
Back down length 0.16
Back lock structure 0.17
Compression 0.19
Haunch bristle length 0.25
Haunch down length 0.15
Homogeneity 0.18
Resilience 0.18
Tautness 0.09

Basically the point here and what the authors seem to be trying to say is that Wool is fairly changeable and subject to improvement by selection. On pg. 335 of the same book it says, "Since heritability is moderate, genetic progress for wool traits will largely be determined by how rigorously the breeder selects. This will in turn depend, in part, on the size of the herd. If the herd consists, for example, of only 2 bucks and 10 does, the breeder cannot practice intense selection because there will not be many offspring from which to select, despite the high degree of genetic influence for wool traits."

In other parts of this book and according to info. I have read from other sources, serious linebreeding cannot occur in herds that consist of fewer than 50 animals. While it is not necessary to have hundreds of rabbits (and not practical in our case with the maintenance needs of an Angora), a decent-sized gene pool is still important to create in order to preserve vigor and variation in your herd. Lots of breeders I know have smaller herds and simply buy stock in from other rabbitries every once in awhile, but I have a closed herd here so I have enlarged my herd to approx. 60 FAs in order to keep going without bringing in new stock.

Another interesting point according to many long term breeders is that it is far easier to improve and set Wool than it is to fix Type. I am finding that wool faults in many of my own rabbits fix themselves in 1-2 generations if I breed each doe to a mate that compliments their shortcomings, but Type is much more difficult to set, and it is a long, slow process of building and improving one section at a time. When I breed to work out a type problem, I find that I need to put alot more thought into what I am doing and who I am breeding in order to improve a certain trait because they do not fix themselves overnight:(.

More stuff next time and have a great week!:-)

Bunny Misc. Stuff

I have come to the conclusion today that it is beyond impossible to take a good picture of a rabbit before the age of 12 weeks:(:(. As I think about it now I realize that I have been trying to do this for years---I have been taking them out, distracting them, encouraging them to pose, cajoling, threatening, holding them down and then releasing them at the last possible second, and using all kinds of silly/useless methods to try to make them do what they obviously do not want to do, which is sit in one place for as long as it takes me to snap a semi-legible picture, LOL.

The littlest ones are the worst, of course. Their nosiness constantly overtakes them until they become so distracted by the table (top, sides, and bottom), the room, kids, walls, camera, etc, etc, that there is nothing to do but forget the whole thing and stick the little buggers back in their cages:). This is the kind of thing that they do:

This,

this,

this,

this,

and my very favorite, which is this:

So from now on I am just going to photograph those bunnies who are mature enough to handle a .236 second distraction on a grooming table, and leave the rest for a later date, LOL:).

I got lots of grooming done this weekend and have more to do again tomorrow, but here are a few of the finished buns who will be staying around here for future showing (with the exception of one or two).

The bunny below is an Ermine, who came out of the last litter of Evariste and Pierre. The color Ermine is not recognized in the FA standard, but it is basically a derivative of the Chin gene that can be used to produce other, showable colors. I am currently playing with the idea of using this rabbit to produce some Chins in the future because it is an absolutely stunning color, but I am not quite sure if I want to add one more project (or color) to those I already have.

This bunny below is another buck out of Eva's litter, a Sable. This bunny is actually for sale at the moment because I have another Sable buck that I am keeping. He is 11 1/2 weeks old and is a very large, solid baby with wonderful density and color. If you would like further details you can email me at amy@spangangoras.com. I will be delivering several rabbits to the Sheep and Wool Festival in Rhinebeck, NY in October and can easily take him along.

And below is an older baby who is currently in Junior Prime at approx. 4 months of age. This is 'Spang's Isadore' and she is a Sable Pearl out of Neva and Dijon.

Below also is a Chestnut buck who is nearly 4 months old (sorry about the horrendous green line running through the picture:( ) out of Devaki and Dijon. He was due to be sold a couple of weeks ago but then I noticed that the ring color in his coat was not developing as it should so I am keeping him here instead. He is a beautiful rabbit with fabulous type and wool, but Agoutis I have had in the past with faint rings in the baby coat did not often develop good definition in the adult coat, so I am keeping him here until the Sr. coat develops to see what happens. If he pans out and looks good then I may use him to produce more and better Chestnuts. If not, he will have to be culled.

This little girl is a littermate to Isadore, the Pearl doe shown above. She is by far one of the best bunnies to come out of my summer breedings---large, well-balanced, with great type and color (and good wool too, LOL). Her name is Spang's Magdeline:

And this is a Fawn buck below---a littermate to the Chestnut buck. He is also a nice bunny with particularly good fawn color, though clearly he is not at his best in front of a yellow wall (LOLOL). This is Spang's Henryi:

There are many more up and coming babies (too young to photograph now) who are also promising and who will make nice additions to the herd. All in all I am very happy with the results of this year's breeding season. Nice litters were born and none of them (with the exception of the Ermine and one lop-eared bunny) were unshowable. There were no genetic DQs, and everyone was healthy.

Anyway, last but not least---here are 3 pics that I included of our trip last week to Mystic Seaport and Mystic Aquarium. The first is of some (crazy!!) people climbing up the mast of a 19th century whaling ship that was on display to furl the sails, and the last are of my boys clowning around behind a painted funny-board in the Seaport village, LOL.

More stuff again next time. Have a great week!:).

Genetic Selection--Part I

-Another repost from the old blog:)


Many experienced rabbit raisers say that the real skill of a breeder lies not in their ability to breed, but in their ability to cull. If we sit down and really think about this, breeding becomes much more of a challenge than it may first appear because there are so many questions to ask about why we are doing what we are doing, and so many things to consider with the variables involved.

Genetic characteristics fall into two general categories, Qualitative and Quantitative. Qualitative traits are those which require only one or a few pairs of genes to express themselves, and Quantitative characteristics are influenced by many pairs of genes. Examples of traits that fall into the Qualitative category include wool color or the presence of wool itself (vs. fur), and examples of Quantitative traits include fertility, growth rate, milk production, wool density, and disease resistance. In other words, the improvement of quantitative traits is difficult and takes longer simply because there are so many genes at work producing effects that accumulate slowly over a much longer period of time (this principle is known as additive gene action).

Here are some portions of a great Table located in the 'Rabbit Production' book on pg. 326 which describes the heritability percentages for certain Quantitative traits. Much of the info. on this chart relates to meat production characteristics, but much of it also applies to the behaviors and traits of practically any rabbit breed. Several characteristics are listed along with a % of heritability for each trait according to the studies that were conducted:

Trait Percent Heritability (range according to various studies)

Litter Size born alive 2.1--10.0
Nest-building ability 24.0
Milk Production 27.0--45.5
Enteritis and Pnemonia deaths 12.0
Body weight: 1 day 40.0
30 days 17.0
56 days 22.6
70 days 12.0--38.0
77 days 19.0
Gain: 28-70 days 17.0
30-70 days 44.0
30-77 days 23.0
Loin Width (56 days): 60.0

There is another, more detailed Angora chart included in this book that breaks down the heritability of certain wool characteristics which I will post later this week. To boil the whole thing down simply---there are certain traits which are very easy to breed into a line, and others which are much more stubborn to set and require more deliberation and effort on the part of a breeder. Things like Milk Production or Growth Rate (which according to this chart are highly heritable), are easier to improve than something like 'Litter Size born alive', which is very vague and would depend very heavily on environmental variables.

I will post alot more on this topic since it is interesting and has alot of bearing on the traits we select for and how much progress we can expect to make in our breeding programs. 'Rabbit Production' sums it up very well on pg. 330 when it says, "the higher the heritability and the more intense the selection, the more rapid the expected rate of progress". If we manipulate traits that respond most readily and then cull hard to get the desired results in our herds, we cannot help but end up with litters that consistently outperform their parents (which is the goal of any good breeder, LOL:)).

Guidelines for Color I.D.

Here are a couple of helpful guidelines to follow for identifying certain colors in the FA standard in the nestbox. Color ID gets much easier and less-terrifying over time, LOL, especially when you own the parents, grandparents and G. grandparents and have a good idea what to expect. Even when the bunnies come from brand new lines though, identifying them is not so difficult if you know what to look for. The colors below can develop into several different varieties depending on what is in the background of the baby and what it carries genetically, but narrowing the field is the first step toward eliminating confusion and helping to identify them as adults later on.

COLOR AT BIRTH--5 DAYS

1) Pink/White--will be either REW, BEW, Pointed White, or Pearl
2) Solid Black--will be either Black, Seal, or Gold or Silver Tipped Steel
3) Solid Brown--will be either Chocolate, Sable, or Gold or Silver Tipped Chocolate Steel
4) Solid Blue--will be either Blue, Gold or Silver Tipped Blue Steel, Sable or Smoke Pearl

5) Solid Grey/Purplish--will be either Lilac or Gold or Silver Tipped Lilac Steel
6) Black with white belly--will be either Chestnut or Chinchilla
7) Brown with white belly--will be either Chocolate Agouti or Chocolate Chinchilla
8) Blue with white belly--will be either Opal or Blue Chinchilla (Squirrel)
9) Tan with white belly--will be either Lynx or Lilac Chinchilla
10) Tan with blue, black, chocolate, or lilac mask and demarcations along the sides--will be one of the Torts
11) Solid Tan--light or dark Red/Orange--will be one of the widebands (Cream, Fawn, or Red), OR possibly Sable because Sable does start off tan in some cases

12) White Splotches mixed in with any other color--will be Broken

I have not included unrecognized colors such as Self Chins, Sable Chins, Smoke Pearl Chins, Ermines, and Tan patterns, etc. in this description, only because they do not occur often and do not fit the accepted color standard for the breed. Unusual colors CAN occur, of course, but they are not that common and only confuse the issue for beginning breeders, so it is better to focus on the accepted ones first:)

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More next time again as life settles down and there are way less bunnies hanging around this place, LOL. We are now down to only about 30 or 40 rascals, so soon I will be able to catch my breath and sit down again, at least until the whole thing starts over in the fall. :-D :-D