Age of puberty in cats

Re: Age of puberty in cats

Thomas Johnson — Fri, 27 Sep 2013 15:54:42 GMT

[quote user="Hannah Wynne Richards"]

Thomas How do you explain the fact that some rivers only contain(morphologically) female fish?

[/quote]

Okay, I've done a bit more reading and found this paper:

http://a0768b4a8a31e106d8b0-50dc802554eb38a24458b98ff72d550b.r19.cf3.rackcdn.com/sw2-014-tr-e-e.pdf

It certainly looks from this as if there is a significant effect of oestrogen related hormones on the sexual development of fish, but it isn't necessarily the hormones from the contraceptive pill that are the main problem, man made oestrogen mimicking compounds and natural human oestrogens are also implicated:

The natural oestrogens 17

b-oestradiol and oestrone were identified by TIE as major contributors to ‘in vitro’ oestrogenic activity of the Chelmsford STW effluent, on the occasions investigated (see table 2). The ratio between the two compounds showed marked variation during Experiment A, but was relatively constant in Experiment B when oestrone was present at a much higher concentration (oestrone concentrations three to 13 times higher than for oestradiol).

The synthetic steroid hormone 17

a-ethinyl estradiol was also detected intermittently outside, but not during, the experimental periods. The alkylphenolic compound, nonylphenol, and its ethoxylates (mono- and di-ethoxylates) were found at higher concentrations than the steroidal oestrogens in both trials. Alkylphenol concentrations varied markedly, however, being much greater in Experiment B than Experiment A. Nonylphenol was below the level of detection in effluents analysed in Experiment A.

Re: Age of puberty in cats

Thomas Johnson — Fri, 27 Sep 2013 14:33:14 GMT

[quote user="Hannah Wynne Richards"]

Thomas How do you explain the fact that some rivers only contain(morphologically) female fish?

[/quote]

The story in the link is based on research in America, but it states that some research cited in the report suggests that animal manure accounts for 90 percent of oestrogens in the environment and that sewage treatment plants remove virtually all of the main oestrogen -- 17 alpha-ethinyloestradiol (EE2) -- in oral contraceptives.

Re: Age of puberty in cats

James Laidlaw — Fri, 27 Sep 2013 11:23:06 GMT

[quote user="Hannah Wynne Richards"]

Thomas How do you explain the fact that some rivers only contain(morphologically) female fish?

There's got to be some environmental abnormality

Wynne

[/quote]

Wouldn't they die out pretty quickly? No males = no offspring

Re: Age of puberty in cats

Hannah Wynne Richards — Fri, 27 Sep 2013 11:06:17 GMT

Thomas How do you explain the fact that some rivers only contain(morphologically) female fish?

There's got to be some environmental abnormality

Wynne

Re: Age of puberty in cats

Thomas Johnson — Fri, 27 Sep 2013 09:50:51 GMT

[quote user="Martin Atkinson"]

Is it anything to do with the amount of hormone women on the pill piss into the sewers and the water gets re-cycled for drinking?

[/quote]

An urban myth I'm afraid:

http://www.sciencedaily.com/releases/2010/12/101208125813.htm

Re: Age of puberty in cats

Anthony Todd — Thu, 26 Sep 2013 17:36:41 GMT

[quote user="Hannah Wynne Richards"]

I've seen plenty of pregnant cats at 4/5 months!

Wynne

[/quote]

Burmese for sure, and remember that it's not the actual age that counts, it's the age when the owner thinks the cat is 4 or 6 or 10 months which is usually way way under the real age.

[sorry, got it the wrong way round! The cat is actually much older than estimated by the owner]

Re: Age of puberty in cats

Hannah Wynne Richards — Thu, 26 Sep 2013 15:12:29 GMT

Opposite end of the reproductive spectrum, and social factors may also play a part, but could the rising numbers of older mothers (40s) have something to do with increasing environmental oestrogen levels?

Wynne

Re: Age of puberty in cats

Anthony Dennison — Thu, 26 Sep 2013 13:49:53 GMT

Or the synthetic oestrogens that people can ingest from drinking water from plactic bottles?

Re: Age of puberty in cats

Martin Atkinson — Thu, 26 Sep 2013 11:30:20 GMT

Is it anything to do with the amount of hormone women on the pill piss into the sewers and the water gets re-cycled for drinking?

Re: Age of puberty in cats

Gillian Mostyn — Wed, 25 Sep 2013 21:05:50 GMT

Time of puberty in girls is strongly related to their weight, where it isn't in boys. It seems reasonable to assume that this will be related to the ability to give birth....not an issue for the boys!

Re: Age of puberty in cats

John Flynn — Wed, 25 Sep 2013 19:01:57 GMT

[quote user="tess"]

Puberty in teenagers now happens around 2 years younger than it did 30 years ago. No one seems to know why, and environmental factors have been suggested. Perhaps cats are doing the same????

[/quote]

Perhaps (with cats) there could be selective breeding also - only those early breeding queens got the chance to reproduce before going under the knife

Are cats actually coming into season earlier than 30 years ago then or have they always reached puberty at this age?

Re: Age of puberty in cats

tess — Wed, 25 Sep 2013 18:52:45 GMT

Not so sure about the boy thing . My son is 12 and there a few in his year whose voices have broken. Link below is for USA but UK is likely to be the same.

http://children.webmd.com/news/20121020/earlier-puberty-age-9-10-average-us-boy

Re: Age of puberty in cats

Hannah Wynne Richards — Wed, 25 Sep 2013 18:35:16 GMT

I could think of at least 3 different reasons for that:

a) girls who train are leaner, and so later reaching puberty

b) girls who are later reaching puberty are naturally better at gymnastics due to their body shape,

and

c) girls who are later reaching puberty aren't distracted by boys, and so train more

Wynne

Re: Age of puberty in cats

Thomas Johnson — Wed, 25 Sep 2013 17:47:10 GMT

[quote user="tess"]

Puberty in teenagers now happens around 2 years younger than it did 30 years ago. No one seems to know why, and environmental factors have been suggested. Perhaps cats are doing the same????

[/quote]

I'm sure I heard somewhere that it's partly due to body condition, girls who compete at a high level in gymnastics and swimming aren't reaching puberty earlier than they used to. Also there hasn't been as big a change in boys as girls.

Re: Age of puberty in cats

Niall Taylor — Wed, 25 Sep 2013 16:41:06 GMT

Surely it depends on weight as much, if not more, than age?

Niall

Re: Age of puberty in cats

tess — Wed, 25 Sep 2013 16:36:46 GMT

Puberty in teenagers now happens around 2 years younger than it did 30 years ago. No one seems to know why, and environmental factors have been suggested. Perhaps cats are doing the same????

Re: Age of puberty in cats

Hannah Wynne Richards — Wed, 25 Sep 2013 16:02:55 GMT

I've seen plenty of pregnant cats at 4/5 months!

Wynne

Re: Age of puberty in cats

Martin Atkinson — Wed, 25 Sep 2013 09:14:26 GMT

[quote user="John Flynn"]

I thought the average age of puberty in cats was around 9 to 10 months? I recommend spaying a cat at 5 months as that's what my forefathers did, and I've certainly never seen one noticeably pregnant at that age - indeed I doubt i've spayed a 5mth cat that even looked like it was in oestrous at the time.

[/quote] I would say that you've been remarkably lucky or living under a bushel John. Not frequent I''ll admit but I've seen a few cats come into oestrus at less than 5 months the youngest was 4, but of course it depends on the time of year. If you assume puberty was 9-10 months then I'd say most of your females would already be pregnant certainly in spring. I now recommend spaying at 4-5 months but tend to leave males to at least 6 and preferably 7-8 as I rightly or wrongly and irregardless of anything to to do with their bone/hip development, believe they benefit from a bit of testosterone to grow into more robust cats. It appears true that males are probably not sexually mature until near 9 months but the consequences of mis-timing it are not so serious are they?!!

Re: Age of puberty in cats

James Laidlaw — Wed, 25 Sep 2013 08:12:24 GMT

I still have some reservations with early neutering in male cats and associated hip disease. Not sure but I think it's more common in those neutered before 3 months - I'm not sure there's a lot of research on this though.

Re: Age of puberty in cats

Linda Filshie — Wed, 25 Sep 2013 07:43:39 GMT

How to tell you're getting old: when adult cats just seem to keep getting younger and younger

Re: Age of puberty in cats

John Flynn — Tue, 24 Sep 2013 23:30:44 GMT

every day's a school day

Re: Age of puberty in cats

Ana Santos — Tue, 24 Sep 2013 23:26:36 GMT

Just last week I got a 5 month old about 2 weeks pregnant. Living with a brother. Barely 2 kg of BW. I've done a few that suspected that were in season. The policy where i work is spaying whenever: as long as over (or very close to) 2kg.