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#60878 - 09/13/02 02:02 AM large japanese quail.
Anonymous
Unregistered


I have 5 japanese quail hens, that weight between 200 and 300 grams each. I have read that the hens are only ment to be between 110 and 150 gram? Is this normal? They lay eggs that are 12-15 grams.

Thank-you

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#60879 - 09/15/02 12:16 PM Re: large japanese quail.
R. Okimoto Offline
Lord of the Fowl

Registered: 07/18/02
Posts: 1498
Loc: Arkansas
300 grams is still within the normal range for Japanese quail. This would be for unselected lines. There are lines of Japanese coturnix that exceed 1000 grams for some individuals of the line. Some people claim that they have obtained quail up to 20 oz (1.25 lbs). Seven Oaks Game Farm used to sell a line that got to be about one lb.

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#60880 - 09/15/02 02:02 PM Re: large japanese quail.
Anonymous
Unregistered


How would I go in selective breeding for larger birds? Would I start off with a 300g hen and 250g male,(or largest I can find) and only breed with the largest offspring?

I dont think there are any of the improved size quail here in Australia yet.

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#60881 - 09/15/02 03:01 PM Re: large japanese quail.
R. Okimoto Offline
Lord of the Fowl

Registered: 07/18/02
Posts: 1498
Loc: Arkansas
Selecting for body size is one of the easiest traits to select for and one in which you can expect to make the most progress. The pitfalls are if you accumulate too much inbreeding and your line falls apart.

If you can maintain a breeding population of a couple hundred birds you can expect to maintain a decently healthy line. You should start with as broad a genetic base as you can find (birds from several breeders). Whenever you select for any given trait you begin to select related individuals because they share the most genes that you want to keep in your line. You have to try and avoid this. To do this you should keep some type of pedigree. This can be as simple as keeping say 4 breeding pens of 60 birds (A, B, C, D, 240 total breeders) and keeping the chicks separate. The next generation you can breed males from A to females from B (your new mating A2) and males from C to females from D (your new mating B2), males from B to females from A (your new mating C2) and males from D to females from C (your new mating D2). Repeat the A to B, C to D etc. In this way you are mating fairly unrelated birds all the time.

For quail selecting body weight at 4 weeks of age has been found to accurately reflect adult body weight. This is an advantage because if you weigh the birds at 4 weeks and cull the ones that you probably do not want to breed you don't have to feed them for another 4 weeks until you start getting fertile eggs. If you use the wild-type Coturnix you can accurately sex the birds at this age and keep only the breeders that you need and a few extra. You should keep 2 females for each male. You should be able to maintain fairly good fertility by mating 20 males to 40 females in a colony breeding cage. As the birds get larger the fertility decreases and you may have to increase the number of males that you keep for breeding.

How much progress you make depends on the accuracy of your selection and the number of birds you raise to obtain your breeders. If you raise 400 birds from each mating (A, B, C, and D 1600 total)the selection intensity would be high because you would be selecting the 10% largest males (20) and 20% largest females (40), and progress should be rapid. Remember to keep extra breeders. The problem is that if disease or other environmental factors make your body weight selections inaccurate. You have to raise healthy stock and raise them all the same way with a good diet.

So, the way to do it would be to gather a diverse genetic stock (there is no use starting with highly inbred stock), make your matings, raise your chicks to 4 weeks of age, weigh them as accurately as you can, keep the ones you like best for breeding along with a few extras, make your next series of matings and repeat.

You can experiment by starting with just a few birds, but inbreeding depression will likely kill your line after a few generations of selection. As the birds get larger their hatchablity goes down. Our large line only has about a 30% hatch rate at this time (they weigh around a pound or more).

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