ARE GINGER CATS ALWAYS MALE?
No. This is a common misconception. Ginger cats can be either male or female although ginger females are less common.
The genetics of ginger is explained in more detail in Tortoiseshell and Tri-Colour Cats (ginger is caused by the same gene as tortoiseshell), but this is a short version for those wanting a quick answer.
The ginger gene changes black pigment into a reddish pigment. The ginger gene is carried on the X chromosome. A normal male cat has XY genetic makeup so he only needs to inherit one ginger gene for him to be a ginger cat. A normal female is XX genetic makeup so she must inherit two ginger genes to be a ginger cat. If she inherits only one ginger gene, she will be tortoiseshell with some ginger areas and some black/brown areas.
The ginger gene is called a sex-linked gene because it is carried on a sex chromosome.
Also, if you look closely, ginger cats have tabby markings though these may be faint or only visible on the face, tail and lower legs. They are also visible in the ginger areas of tortie cats. This is because the gene that turns off tabby to give solid colour cats does not work on the ginger colour.
ARE GINGER FEMALES RARE?
No. They are less common than ginger males, but they are not rare. It is possible to selectively breed ginger female cats by mating ginger males and ginger females together. They will have ginger offspring.
ARE GINGER FEMALES STERILE?
No. They are just as fertile as other female cats!
IF THE GINGER CAT HAS WHITE MARKINGS, DOES THAT INCREASE THE LIKELIHOOD IT IS FEMALE?
No. This myth was sadly propagated in a British cat magazine that should have known better! White spotting is not sex linked. It isn't related to the cat's gender and it cannot influence the cat's gender. The relative frequencies of ginger-and-white males and females is the same as ginger-without-white males and females.
ARE TORTOISESHELL AND CALICO CATS ALWAYS FEMALE?
No. Though they aren't very common, tortoiseshell and calico males occur more often than most people realise and more of them are fertile than people realise.
The genetics of tortoiseshell males is explained in more detail in Tortie Tomcats, but this is a short version for those wanting a quick answer.
WHAT CAUSES TORTIE AND CALICO TOMCATS?
The most common cause seems to be chimerism. Two embryos bump into each other in the womb and merge together. If one is black and the other is ginger and one or both are male the result may be a tortie tomcat (or calico tomcat if the embryos had white patches).
The next most common cause seems to be XXY genetic makeup (Klinefelter Syndrome). An embryo gets one X chromosome with the black gene, one X chromosome with the ginger gene and one Y chromosome that makes it male. This chromosomal abnormality used to be thought the most common cause, but recent research shows chimerism is probably more common.
The third cause is somatic mutation. A ginger male embryo devlopes black patch in the same way as some babies develop port wine stain birth marks.
ARE TORTIE AND CALICO MALES ALWAYS STERILE?
No. It depends on which of 3 conditions has caused their colouration.
Those with XXY makeup are infertile and often have other physical abnormalities due to having too many copies of some genes..
Those with chimerism are fertile but they can only pass on either the ginger colour or the black colour, but not both, to their offspring.
Those with somatic mutation are fertile because the black patches are just birthmarks.
ARE TORTIE AND CALICO TOMCATS VALUABLE?
No, but people who advertise them as "rare" would like you think so!
Because they are either sterile or they only pass on either ginger or black to their offspring, they are no more valuable than any other cat (value will also depend on what breed it is). Some superstitious people think they bring good luck.
ARE WHITE CATS ALBINOS?
Most white cats are not albino. Albino means a total absence of pigment. Albino cats will have pink eyes or very, very pale blue eyes.
ARE WHITE CATS ALWAYS DEAF?
No. There are several genes that cause the white coat colour. Only some white cats will be deaf.
The genetics of white cats, blue eyes and deafness is explained in more detail in White Cats, Eye Colours and Deafness, but this is a short version for those wanting a quick answer.
Pure white cats with blue eyes are more likely to be deaf than white cats with green, yellow or orange eyes. They have the Dominant White gene which can affect the way the inner ear develops.
Pure white cats with one blue eye may be deaf on that side.
White cats with tiny smudges of colour, or which had tiny smudges of colour when they were kittens, are less likely to be deaf because the white colour is caused by a different gene called White Spotting.
White cats that have Siamese ancestry are less likely to be deaf because they have the "Siamese Blue Eyes" gene (a type of albinism) which isn't linked to deafness.
WHAT DO CATS USE THEIR TAILS FOR?
Among 4 legged animals, having tails is more common than not having tails. What's more interesting is not why a cat has a tail, but how it uses its tails.
Cats use their tails for balance. Watch a cat walking along a fence top or chairback and you'll see it move its tail as a counterbalance - a bit like a tightrope walker using a pole. Cats also use them for communication - there's a diagram near the bottom of Cat Body Language. The tail tells other cats (and owners) what mood the cat is in. There's even one theory, not widely accepted, that the stripes on a wildcat's tail and the cat's ability to hiss fool predators into thinking it is a snake.
Another use of the tail is to help the cat defecate. The muscles at the base of the tail where it joins the body are used in squeezing the faeces out of the rectum (where it is temporarily stored ready for a convenient opportunity). If you watch a cat doing defecating you'll see it jerk its tail sharply downwards a couple of times as it finishes - a bit like a toilet flusher. That empties the rectum.
Cats that completely lack tails can have problems with incontinence or constipation. Some Manx cats can have this problem as do cats that have lost their tails in accidents (vets try to leave a stump of tail). Owners of affected cats have to manually express faeces from their cat's rectum.
INFERTILE STUD CAT - WILL HORMONES HELP?
An 18 month old male failed to impregnate several different females over 3 oestrus cycles each. He was unrelated to the females who were proven breeders. The male had not previously been used in breeding, but was seen to mate the females each time. He was physically mature and both testicles had descended, but were noted to be rather small and the stud was sexually unaggressive. The breeder queried the use of hormone shots to improve the chance of kittens.
Hormone shots might increase the eagerness to mate and the frequency of matings, but would not change the underlying infertility. He might not be making any sperm; he might make sperm that is defective (not motile, deformed, unable to penetrate the ova etc) or an anatomical malformation might prevent the sperm from being ejaculated. Extra hormones would not fix any "broken machinery".
Getting a sperm count done isn't common in domestic cats, but it isn't impossible and it has been done with wildcat species in conservation programmes. To obtain a sperm sample, the stud cat must be sedated/anaesthetised and ejaculation is triggered by a electrical pulse to the prostate. The ejaculate can be analysed to see how many sperm are present and if they are healthy. Getting a swab from a female just after mating might be an easier way to obtain a sperm sample; the results would be less accurate, but it would be possible to see if sperm are present and whether they are normal.
If the problem is one of low sperm count, increased mating frequency would improve the chances of conception, but there are serious implications for the breeding line. If the cause of the poor fertility is genetic, the offspring would carry this trait into future generations.
WHY ARE THERE NO PORK CAT FOODS?
I did a study on cat foods during my University days and one of the topics was the range of flavours. In general, these mirror the foodstuffs and flavours in each country's human food chain (since humans are the purchasers) and are constrained by any prohibitions on certain ingredients (in the UK, equine is a prohibited ingredient) or local availability of ingredients.
There is nothing intrinsically wrong with pork as a pet food. It is no more likely to cause diarrhoea than any other meat. According to the PFMA (Pet Food Manufacturer's Association), pork is a permitted meat. Whiskas produced a Pork variety for a short while (available only in the small size cans), but this wasn't around for long. While it may not be specified as "pork" or "pig", the ingredient of "meat byproducts," "meat derivatives" or "animal byproducts" can include pork. In the UK, there are several varieties that contain ham or bacon (also pig products) in combinations e.g. chicken-and-ham or chicken-and-bacon varieties. Overseas, I've seen a canned rabbit-and-pork variety.
Historically, pork had a bad reputation because it was associated with tapeworm. Any tapeworm eggs would be killed off by the high temperatures used in cat food manufacture. There may simply be less pork left over from the human food chain. Much of what's left after on a carcass ends up in sausages or pork pies. Even pigs' trotters can be eaten. It's joked that "everything but the squeal" gets used.
There are people that consider pork unclean or offensive for religious reasons which might be another reason it doesn't appear as a flavour, but may be present as a meat or animal byproduct/derivative.