I’ve just bumped into a Google Scholar study which tells me that tomcats (male cats who’ve not been sterilised) produce more sperm during the months of July to December than at other times of the year “thus indicating increased accessory gland activity during the breeding season”. The breeding season is spring and summer. But it did not occur to me that tomcats increased sperm production in during the season despite making sense.
An important point here is that the study was conducted in Brisbane, Australia. Their seasons are different to those in northern Europe hence the fact that the “sperm counts were higher in the latter half of the year, at the time of increased sexual activity for cats in the Brisbane area.” Spring is September to November in Brisbane. Summer begins in December until February.
The scientist discovered this through a method called electroejaculation which sounds horrendous but which apparently causes no discomfort and has no harmful effects. I presume they used electricity to stimulate the tomcats into ejaculating.
The study authors state that there was a large variation between the amount of sperm collected because it depended upon how long the electroejaculation went on for (also makes sense). The normal sperm counts in four cats ranged from 6-13 times 10Vejacute. I don’t know what that means to be honest.
The study authors suggested that as electroejaculation does not cause discomfort or harm “there seems no reason to assume that it could not be used routinely on stud cats”. The suggestion would seem to be that cat breeders should employ the method to understand when their stud cats are at their most fertile and improve their breeding practices. But perhaps they know or expect their stud cats to be in the mating mood during the season. But the findings of the study might allow breeders to fine tune their breeding practices.
I don’t have any more information because this article has been written on the basis of a short summary. The study author is I. Johnstone. This link takes you to that summary: https://doi.org/10.1111/j.1751-0813.1984.tb07220.x. It is published on the Wiley Online Library website.
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