Cheetah Semen Is Much Worse Than Domestic Cat Semen

by Michael
(London, UK)

Baby Cheetah - greatly inbreed - photo by San Diego Shooter (Flickr)

Two useful tags. Click either to see the articles:- Toxic to cats | Dangers to cats

Baby Cheetah - greatly inbreed - photo by San Diego Shooter (Flickr)

Yes, the sperm of a cheetah, the fastest land animal on the planet, is much worse than the sperm of the common domestic cat, the companion animal that you and I live with and from which we derive so much pleasure.

Eighteen cheetahs were subject to ectroejaculation. This sounds unpleasant. Ectroejaculation is a procedure that is usually carried out under general anesthetic and which is used to obtain semen samples from sexually mature male mammals. An electrode is inserted into the rectum and a small electric shock applied stimulating an ejaculation1.

The semen was obtained from Namibian and Transvaal cheetahs. Namibia is the home of the cheetah but populations are declining all the time (cheetah habitat).

Spermatozoal concentration and motility levels in the cheetah were one tenth of those of the domestic cat, on my reading of the data. Also the number of 'aberrant spermatozoal forms' where considerably higher in the cheetah compared to the domestic cat - 71% to 29.1%. 'Motility' means: the ability to move spontaneously and actively, consuming energy in the process2

Cheetah semen is 'markedly' inferior to that of the domestic cat. There is a much higher incidence of spermatozoa that takes on a different shape or that is a variation from the normal (= abnormal sperm, as I understand it).

The much higher level of genetic abnormalities in the cheetah are put down to inbreeding in the cheetah that has resulted in genetic homoygosity (the possession of two identical forms of a particular gene, one inherited from each parent). It said that one cheetah is almost a clone of another. The cheetah is higly inbreed. This increases the chances of mutant recessive genes becoming effective in producing unwanted phenotypes.

Why is the cheetah inbreed? Does this result in less virile animals? Does it further endanger this already endangered wild cat?

The inbreeding it is thought is a result of a population crash thousands of years ago. The Siberian tiger suffers from inbreeding reducing its fertility. There are 400 Siberian tigers but the population from a breeding standpoint equates to just 35 tigers (see Siberian tiger habitat). Is is argued that poor sperm causes infertility (see also male wildcat roaming).

There are arguments about the cheetah and how its fragile genetic makeup affects is prospects of survival. Some say it makes no difference. But one thing is for sure, on a classic measure of genetic health, the humble domestic cat is far healthier and is far better placed to survive.

There are about 500 million domestic cats in the world and there are 7,500 adult cheetahs3. You decide.


Major source: Unique seminal quality in the South African cheetah and a comparative evaluation in the domestic cat by: D E Wildt, M Bush, J G Howard, S J O'Brien, Meltzer, A Van Dyk, H Ebedes and D J Brand




4. Flickr original photo

Cheetah Semen Is Much Worse Than Domestic Cat Semen to Wild Cat Species

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Cheetah Semen Is Much Worse Than Domestic Cat Semen

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Jun 15, 2011 Clarification
by: Anonymous

Michael -
I would like to further clarify a few things.
Sperm morphology, motility and other parameters of an ejaculate are characteristic of an individual's spermatic phenotype, e.g. normospermic (< 60% normal sperm) or teratospermic (> 60% normal sperm). This phenotype will dictate the quality of the ejaculate throughout the male's life. Populations of animal species will have proportions of each phenotype, and it is suggested that as populations and genetic variability continue to decline, the proportion of the phenotypes can be skewed toward teratospermia. There are teratospermic domestic cats, humans, and males in most species that have the same quality of semen as teratospermic cheetah, so it is not necessarily that the entire species is normo- or teratospermic. Additionally, of the Siberian tigers that have been analyzed, the ejaculate quality suggests this species has a higher proportion of normospermic than teratospermic individuals (Pukazhenthi et al, 2006; Theriogenology 66:112-121).
It is not correct to describe the cheetah as containing a "fragile genetic make-up". It has low genetic variability and is highly specialized which are correlated to a higher risk of extinction due to the susceptibility to the same illnesses and a lack of ability to adapt to changing environments - something human beings are rapidly doing by introducing new species into ecosystems that spread disease and have no natural predators, displacing native wildlife with domesticated livestock, etc.
"Abnormal" sperm morphology can refer to many things, some of which do not necessarily interfere with fertility, e.g. cytoplasmic sperm droplets, but would not normally be seen on a normal spermatozoon. Sometimes these abnormalities can be induced by the medium, e.g. coiled tails, or method used to collect the sample, e.g. cytoplasmic droplets. Abnormalities which occur during actual spermatogenesis, like abnormal acrosomes or cephalic characteristics, would actually interfere with fertility and are seen to be a problem at a higher, potentially genetic, level.
Finally, the method is termed electroejaculation, and the probe is specifically designed for a species by taking measurements and tailoring the probe to maximize the surface area contact with the rectum while not causing damage. This is incredibly important in other taxa with intestines prone to perforation. Please be careful when describing this to others, as it can be misconstrued. Many people do not understand how difficult it is to breed non-domestic cats in captivity, and because human beings are not willing to stop breeding (as you pointed out), semi-drastic measures are required to aid natural breeding.

Jun 03, 2010 Reason
by: Michael

Hi Tracey, it is said that the original reason for inbreeding goes back tens of thousands of years but modern trends of population decreases only serves to compound the problem. Habitat loss is one reason for lower populations. Cheetah are also shot as they often live on farmland.

The Siberian tiger also has inbreeding problems as do captive tigers and all captive cats for that matter.

I only see one way, down, for all of the wild cats as long as the human population goes up - its logical.

Michael Avatar

Apr 19, 2010 Very interesting
by: Tracey

Hi Michael

I was very interested in your article however I've not yet had chance to read all the links.

Could it also be that the cheetahs natural habitat is slowly dissapearing thus forcing them closer togeather which is increasing interbreeding on the whole?

Our domestic cats are very adaptable generally whereas a Cheetah can only survive in certain circumstances or in captivity.

When their natural habitat is disrupted surely this can affect so much i.e. food sources, increase in predators on their young etc.

A domestic cats way of life can be turned completely upside down and yet he can adapt and survive, mainly because he has more at his disposal.

This is just my opinion however I'm certainly no expert!

3 thoughts on “Cheetah Semen Is Much Worse Than Domestic Cat Semen”

  1. I want someone to help me find serval semen for artificial insemination to a Bengal. I know it is being done. But where? I prefer this method rather than purchasing a serval. We will pay several hundred dollars to acheive this. Thanks.


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