Why are we hatching so many males?

[Del1977]

My 12yo daughter is trying to start up a coturnix quail business to may pocket money but having trouble building up her breeding groups as she keeps hatching a large percentage of males. (and also having poor hatch rates, but that's another thread). Last hatch that is now old enough to start sexing there are only 2 obvious females out of 11. One is white though, so not sure how to sex that before it reaches maturity. They are 4.5 weeks old. And previous batch she only got 2 females out of 8! Have another just hatched batch so fingers crossed there are enough females in that batch to get things up and running. She wants two groups of 5 females to one male.

Is there anything that influences gender? Wouldn't be so bad if she was getting 50/50 mix or the opposite mix to what she is getting, but to be hatching so many males all the time is just frustrating. And they are harder to sell.

 

[fishforbrains]

I wish I knew. I've hatched out two batches of courtnix- first one was 100% male, which was a) unbelievable, and b) a real blow since we want them for eggs. They were tasty, though. Second batch I went for jumbo browns instead of the regular size, from a different egg supplier, and although they are only 3 weeks old it looks like we are doing better with four females and two males.

 

[Invision]

Some say studies think that heat changes the % of males to females. I know that in Reptile world see this easy.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1629050/

Really it just takes time figuring out what works for you with your incubator. My last two dry hatches I went on the low side of temp, first batch (15 eggs) I ended up with 3 males 12 females, this last batch I set 48 eggs and so far it's looking like more females than males. same incubator same temp as the last batch. First time I hatched quail I listened and followed all the instructions on here and I ended up with 10 females and 22 males... that was a styrofoam incubator with 99.5 to100.5 ratio 45% humidity... My incubator now runs at 22% and I check only the egg temps daily with one of those kid thermometers for your forehead... make sure the egg temp center is 99.1 to 99.4. As stated though I've only done this test on 2 batches so don't base your incubation on my numbers.

 

[Del1977]

Some say studies think that heat changes the % of males to females. I know that in Reptile world see this easy.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1629050/

Really it just takes time figuring out what works for you with your incubator. My last two dry hatches I went on the low side of temp, first batch (15 eggs) I ended up with 3 males 12 females, this last batch I set 48 eggs and so far it's looking like more females than males. same incubator same temp as the last batch. First time I hatched quail I listened and followed all the instructions on here and I ended up with 10 females and 22 males... that was a styrofoam incubator with 99.5 to100.5 ratio 45% humidity... My incubator now runs at 22% and I check only the egg temps daily with one of those kid thermometers for your forehead... make sure the egg temp center is 99.1 to 99.4. As stated though I've only done this test on 2 batches so don't base your incubation on my numbers.

Interesting. Our most recent hatch, now 4 days old, were set 0.2 degree Celsius lower than previous batch in an attempt to induce a slightly later hatch as we were away for the weekend, returning only on hatch day, so will be interesting to see if we have more females. You've had the kind of ratio we need!

 

[Invision]

Interesting. Our most recent hatch, now 4 days old, were set 0.2 degree Celsius lower than previous batch in an attempt to induce a slightly later hatch as we were away for the weekend, returning only on hatch day, so will be interesting to see if we have more females. You've had the kind of ratio we need!

Remember though, mine is internal egg temp not incubator temp. Just because you dropped the temp in the incubator doesn't mean the eggs are less. Only way to know for sure is checking the egg temp.

 

[fishforbrains]

In birds. just as in mammals, sex is determined by what type of chromosomes end up in the fertilized egg. Mammals have an XY system where XX is female and XY is male. Birds have a WZ system where ZZ is male and WZ is female. Incubation conditions can preferentially kill off one sex, aka maybe WZ quail embryos are very heat-intolerant and even a half-degree to high could reduce WZ hatch rates, skewing your sex ratio but also reducing your hatch rate and possibly reducing the health of the chicks that do hatch.

See here:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1629050/
To our knowledge, there is, so far, no evidence that incubation temperature can affect sex ratios in birds, although this is common in reptiles. Here, we show that incubation temperature does affect sex ratios in megapodes, which are exceptional among birds because they use environmental heat sources for incubation. In the Australian brush-turkey Alectura lathami, a mound-building megapode, more males hatch at low incubation temperatures and more females hatch at high temperatures, whereas the proportion is 1 : 1 at the average temperature found in natural mounds. Chicks from lower temperatures weigh less, which probably affects offspring survival, but are not smaller. Megapodes possess heteromorphic sex chromosomes like other birds, which eliminates temperature-dependent sex determination, as described for reptiles, as the mechanism behind the skewed sex ratios at high and low temperatures. Instead, our data suggest a sex-biased temperature-sensitive embryo mortality because mortality was greater at the lower and higher temperatures, and minimal at the middle temperature where the sex ratio was 1 : 1.

 

[Invision]

There you go, someone with schooling answered. I for one did not want to go to class for that long... Thanks for the info, definitely keeping this in my favs!

 

[HammerSA]

I myself, have just started breeding with 2 males and 4 females (Ratio 1:2 obviously). Hatched in a cheap 12 egg chinese incubator, which to give them their due was not that far off. Checked the temps with 2 other thermometers and one other hygrometer. The only problem? Temp was out by 0.3 deg C. So perhaps I got lucky. Nonetheless I can give you this info regarding the humidty. The first batch I started with the incubator completley dry and only added 2ml of warm water, which bumped the hum. to 70%. Thereafter I only replaced 2ml again when the alarm went off at 45%. So it was a 45% to 70% swing until taking the eggs out the turner to hatch. Then filled all 5 trays with water and let it sit at 80% all the way. 12 hatched, but had to cull 6 due to curled toes ( NOT splayed leg). The next batch of 20 odd eggs upon starting, I added 4ml of warm water and again up to 70% and would refill 4ml warm water every time 45% alarm went off. When setting to hatch also filled all five trays full and let hit 80%. Had 15 hatch, culled three due to curled toe/splayed leg. Had 12 up to today where one dislocated leg and had to be put down sadly at a week and a half old, and he was a nice big one too. This has been my experience and I am by no means an expert on breeding quail, but these have been my limited findings so far according to my records. I hope this will help you in some small way and keep perservering. My apologies tje reason for thi sthread is male/females. The first batch out of the six now have one definate male, one maybe and the rest are all female. The 2nd batch I will have to keep tabs and let you know, as they are only 1 1/2 weeks old.

 

[fishforbrains]

So it seems that if you're getting an odd male:female ratio there's something off about your incubation conditions that is preferentially killing the females in the eggs. My first batch, all male, did have a very low hatch rate and I suspect it was a little too hot-the thermometer I was using apparently reads low (I checked it against two other thermometers). The second batch, where I got closer to a 1:1 ratio was incubated at about half a degree lower.

-I've only had problems with splayed legs when I tried to use a homemade incubator and hand-turning, meaning lots of fluctuations in temp and humidity. I got good hatch rates, but both batches of Gambel quails had really high rates of splayed legs. Haven't had a single incidence of splayed leg in any of three species of quail since I bought a hova-bator with an automatic egg turner.

 

[Del1977]

Any reason why you culled the ones with leg problem rather than trying to fix? Just curious, as I know it can be fiddly. We have successfully fixed all our quail with curled toes and/or splayed legs, no that we have problems with every hatch, and it does seem to be more common in the late hatches that require assistance, but have never had to cull any for that reason. Had to put cull one that had a slipped Achilles that we couldn't fix and have had to cull two that had serious skull deformities. Curled toes and splayed legs are pretty easy to fix it you want too, but I realise some people only want to breed the fittest and strongest and would rather cull any with problems.