WARNING! Photographs and information on this page although
of an informative and scientific nature, may offend or distress.
Split Penis
What is split penis?
This is seen in varying degrees as an incomplete closure of the
urethral opening on the underside of the penis. It can show as a minor split at the tip to all the way down to the base. Occasionally
it may only be split at the base.
As
a result young bucks are often mistaken for does. It is not until they have either developed testicles or if left unchecked
at that point, then when put to a buck for a mating that it becomes evident.
Characteristically the penis will have a curve to it when sexed and may not
be able to achieve a full erection.
The buck may be fertile, dependant on where the split is located,
as some sperm may find its way to the right place.
There are many theories about the causes of split penis. We believe it is
a recessive genetic trait and therefore is carried by both the buck and the doe.
This condition causes no pain or discomfort. However it is an undesirable trait, care should
be taken not to line breed with carriers or those displaying the condition.
Below are some photos
showing a split penis, by kind permission of Donna Williams MPCS from Whistler, BC, Canada
(http://www.snow-berry.com/welcomehollands.htm)
Donna has recently shown these photos to an ARBA convention (Nov 09) in an attempt to make more people aware
of the problem.
Below, picture of a young buck, just over 9 weeks old with split
penis. The penis often appears to resemble an elongated vulva.
Below, 3 pictures of a buck with split penis. In adults bucks, at
first glance the penis can appear normal, until you examine the underside.
Below, picture of a doe for comparison.
Line Breeding
What is line breeding?
Line breeding is essentially
another word for inbreeding, although line breeding is a less taboo term. It could be considered as inbreeding but
with a pedigree.
A traditional example of line breeding would be mating
father to daughter> father to granddaughter> father to great granddaughter.
However,
other methods can include; half brother and sister or cousins. This is a more gradual way of line breeding and ultimately
means that you will not have to outcross as often as less genes will be shared.
It
is highly recommended that you DO NOT mate full brother to sister.
Why
line breed?
Most exhibitors will line breed to ‘set’ good type. When line breeding you get to know your stocks development
and can easily identify desirable characteristics and in turn undesirable.
Line breeding is also a good technique to use when limited
on space or stock.
Importance
of out crossing (bringing in new blood)
We would highly recommend out crossing every third
generation. It is important to do this, as with every generation you are increasing the risk of doubling up on problematic
genes such as malocclusion, split penis, non descended testicle(s). It can make the difference between a defective gene being
carried or being displayed.
Remember any faults you do find are ones that are already being carried in your lines. It is better to discover any
problems sooner rather than later as this way you can take steps to breed out the problematic genes.
Click
either here or here for probably the most in depth readings on the subject we could find on the internet.
Below
is an example of a line breeding chart.
Reproduced
with permission from Pamela Nock |
The line-breeding chart to the
left shows a common method of crossing a paternal (buck) and maternal (doe) line. Blue represents the paternal line
and red represents the maternal line.
"A" (buck) and "B" (doe) are the two original rabbits
the breeder is starting with.
"A" and "B" are bred together, producing the litter "C"
(doe) and "D" (buck). The litter has 1/2 of the paternal and 1/2 of the maternal lines and is the "F1"
generation.
"C" is bred back to her sire "A" which produces the doe "E". "E"
has 3/4 of the paternal and 1/4 of the maternal line. "E" is an "F2" generation litter.
"D"
is bred back to his dam "B" which produces the buck "F". "F" has 3/4 of the maternal line
and 1/4 of the paternal line. "F" is an "F2" generation litter.
The doe "E"
is bred back to the original sire "A" producing the buck "G" who is 7/8 of the paternal and 1/8 of the
maternal line. "G" is an "F3" generation litter.
The buck "F" is bred back to the
original dam "B" producing the doe "H" who is 7/8 of the maternal and 1/8 of the paternal line. "G"
is an "F3" generation litter.
At this point
in the breeding program, the 7/8 "F3" generations can be crossed to each. The buck "G" will be bred
to the doe "H" producing the "F4" generation litter "I" which contains 1/2 of the paternal and
1/2 of the maternal line.
"J" is a new buck that will now be introduced by breeding to the doe "I"
producing litter "K" which has 1/2 of the new paternal line, 1/4 of the original paternal line and 1/4 of the original
maternal line. Litter "K" can now be bred to "G" and "H" beginning the process over again
now using "G" and "H" to breed subsequent offspring back to.
If a trio was used to start the
original herd, two separate lines can be started with each original doe, and the two lines crossed when reaching the "F3"
generation. |
Breeding rabbits
& the dwarfing gene
Breeding rabbits isn't all cute fluffy happy endings. There are the obvious concerns such as finding homes
for all the babies. Scattered litters, the over zealous mum who takes her cleaning duties too far and chews off the odd ear,
cannibalism to abnormal kits. There is a great deal to contend with.
There are several different types of
abnormal kits you may come across if you are breeding mini lops (some are found in other dwarf breeds of rabbit too)
The
most common form of an abnormal kit is the peanut.
Firstly, you need to know that there is the false dwarf (DwDw)
and the true dwarf (Dwdw). Each rabbit will carry the genetic code to determine its size. Peanuts occur
when two true dwarfs are bred together. A peanut is the result of receiving two doses of the (dwdw) gene. Chances of producing
peanuts in such a litter are 25%. The peanut is a congenitally defective kit that fails to thrive. Some will be born dead; others
will survive a few hours or days. Dependent on what else is on the genome, it may survive several weeks, but the outcome is always the same, death.
Whether it is the pituitary gland that malfunctions and will not
release enough growth hormone to sustain the kit or a failure of
the target cells and organs to respond to this hormone we are unsure of. Peanut kits are easily identifiable
as they are usually a 1/3 size of their normal sized litter mates. The eyes are usually bulging, the ears very small and the
pelvis area and limbs are smaller than normal.
Comparison. True dwarf above, 'peanut' or double dwarf below.
The eyes are usually bulging and ears very small.
The pelvis area and limbs are smaller than normal.
We have never witnessed Max Factor or Hippo kits and do not know of anyone who has, but there is
information to be found on the internet.
Another
type of abnormal kit is the foetal giant. Due to the stress of a prolonged and difficult delivery of the oversized kit, usually
2 to 3 times normal size, it will have died from asphyxiation. The following kits, if any, will either been born dead or may
be delivered alive but are normally scattered by the mother due to stress.
It has been suggested that over feeding a pregnant doe may be the cause
of this. Most breeders keep a pregnant doe on her normal rations increasing only in the last week before she kindles.
Pregnancy and kindling in does is not stressful to their bodies, it's the feeding that takes its toll on the doe, at which
point she should be fed freely.
An
additional area for consideration that may be a cause of a foetal giant is when conditions for kindling aren't
exactly right. That is to say lack of light/heat/correct nutrition.
Consider in nature, what time of year the mating occurs? From Spring time and onwards when the vegetation
is growing, perfect for nourishing the pregnant and lactating doe and later her kits. So, perhaps if any of these requirements
are missing the does body will have some resorption of the foetuses to give the remaining one (or more) a better chance of
survival. As a result more nutrients will be supplied to just one foetus or few, certainly less than initially conceived.
Conversely, extreme heat may also cause this condition.
Nature can be cruel. It is important that should you decide to breed you consider these complications and the possible
outcome.
Occasionally the dam may be at risk her self due to a kit being stuck, requiring an immediate visit to the
vets. Removal of a stuck kit can be done by an experienced keeper, but if due care is not taken, injury to the dam or
the breaking apart of the stuck dead kit may cause further complications. Stroking a doe gently but firmly on her abdomen
may sometimes encourage contractions.
Some does will retain kits, often
being delivered dead several days after the rest of the litter or may retain their kit(s) indefinitely which may result
in either infertility or an infection.
