Where you live can also affect when the first heat occurs--amount of daylight. I had pups from the same litter go to the south and the midwest. Southern pups came in at 6 mo.; other pups at a year.

My "norm" in the midwest is 12 months, although I had one at 14 months.

MWK

Earliest 8 months, latest 22 months.

Yes that is correct. Daylight does have an effect. My two girls that are 11 months show no sign of coming in season, but their littermate who lives 3 hours south went into season 2 weeks ago. My line usually comes in between 12-18 months when they live here in the NE.

I had that same thing where the 2 girls I kept went into season at about 13 months, one of their sisters that went south to N.C. came in at 9 months and the other sister down in PA at 10 months. I guess that's one more thing about "Living in New England"..... :)

The latest I've had was 19 months.

Most of mine are on a 6 month cycle and thats when they start. Longest is 2 years.

15-18 months here in the North for the first heat. I also find daylight affects heat cycles. When I have a girl due to come in during the winter, I keep the fluorescent light in my mudroom on until 10 pm. When I did not do this - heat cycle would be as late as 9 months after previous cycle, but when light is left on they cycle every 7 months.

(I also find keeping light on keeps pigment of nose blacker mid winter.)

Mine are 9 months and nothing yet. Not worried and I know my boys will let me know when it's time!

Johanne

I think it depends on lines... my oldest came into season for the first time around 8.5 months of age. I have heard that her daughters have come in for the first time as early as 6.5 months. My yellow girl came in for the first time at 15 months of age, her dam came in at 14 months for the first time. I have a female puppy that is young so it will be interesting when she comes in for the first time :)