Should TEMP be "lowered a bit" late in incubation?

[Junkmanme]

Howdy, Folks!

In looking for something else on the Internet, I came across an interesting "study" regarding incubation of "meat chicks" (presumably Cornish X).

I provide here the "link" to the article for the purpose of promoting a discussion on this Forum:

http://ps.fass.org/cgi/content/full/86/12/2685

Could it be that a "slight reduction" in temperature (say 1 or 2 degrees F) after day 14 could possibly produce HEALTHIER CHICKS ?????????

I'd be very interested in comments from experienced hatchers........

Whatta ya Think?

-Junkmanme-

 

[rebelcowboysnb]

I have thought about running my hatcher a few degrees cooler an see how that works.... Never actually tried it..... As for the link, its not very readable. Maybe its just me but hes got to much going on at one time to be able to easily keep up.

 

[Katy]

I never have and would think it would just lead to delayed hatching.

 

[Akane]

This experiment does not test lowering incubator temperature and the effects. It only tests incubating high versus normal temperatures and of course found that high temps were bad. The only direct mention I see to incubating lower the last few days being beneficial is quoting another study. Otherwise they only lowered the incubator air temp because they were measuring internal egg temp. The same as anyone on here using a water wiggler would adjust to that temperature instead of the air temperature. You could infer that lowering the temperature might help but there is no test here proving it. You would have to run your own experiment.

 

[muddstopper]

I dont think some of you folks read the entire study.

The present discussion concerning high or normal incubation temperatures referred only to the egg temperature and not to the incubator air temperature, because the 2 were not the same and could not be compared in a consistent manner. As demonstrated in Figure 4, when the machine air temperature was 37.3°C on E14, the internal egg temperature reached 38.2°C. To maintain the internal egg temperature at 37.9°C on E19, the machine air temperature had to be reduced to 36.3°C, a difference of about 1.6°C. These findings were in agreement with Meijerhof and van Beek (1993) and Lourens et al. (2005), who showed that air temperature was simply not equal to embryo temperature and that embryo development and hatchability were more likely to be influenced by embryo temperature than by air temperature. Incubation has been not only characterized as 1 of the most critical components of overall broiler performance but apparently has now become 1 of the more difficult parts of broiler management, because it can no longer be assumed that the internal egg temperature will be the same as the machine air temperature and must be measured independently (Meijerhof, 2000; Lourens et al., 2005).

If you do the temp conversions you will see that they where not running excessive high temperatures. what they are saying is that the internal egg temps and the air temps are not the same. Incubator air temps where 37.3C or 99.14F. Since most incubator temps recomendations call for temps of 99.5. I would say the temps used in the study are right in line with what most of us try to achieve. Still, at the 99.14 air temperature, the internal egg temps would be around 38.2C or 100.76F. To maintain an internal egg temps of 37.9C, or 100.22F the air temperature had to be lowered to 36.3C or 97.34F. The study also went on to say that as the incubating chicks developed that their development caused an increase in internal egg temperature. The net result of these increased egg temperature leads to malformed organ development. The study also went on to say that it was these increases in internal egg temperature that could be part of the problem with sudden chick death syndrome and other problems that result in the premature death of the chicks.

Now how much of this is true, I am not in a position to say, but how many times have you had chicks pip and not hatch or die prematurely during the incubation process, or simply have eggs to stop developeing. It could verywell be that in our attemp to maintain a steady incubator air temp of 99.5F during the entire incubation period, that we are actually causeing our own hatch rates to decline. I think this study is well worth considering and would merit further experimentation with our own incubations.​

 

[Junkmanme]

In line with what muddstopper has commented, It seems that as the embryo develops, it is producing heat also. Therefore my thinking that perhaps a very SLIGHT decrease in temperature after perhaps the 14th day might actually be a help to developing "healthier" chicks.

As Katy said, it MIGHT delay the hatch a day.....but, that really is insignificant to the "Backyard Chicken" raiser.

I need to re-read the article myself to try to glean more than just a "cursory" understanding of it.

It does get one to thinking....

-Junkmanme-

 

[Akane]

Actually most of my hatches with the biggest number of dead in shell after pipping were on the low side for temps. I've had better hatches at 104F than when I let the temp drop to 98-99F the last week figuring it was better than risking it getting too hot. I can't say that has anything to do with the number that died though. I'd rather place my bets on humidity if I had to. However even though I don't believe temp is the reason for the hatches I've had higher deaths I really think dropping the temp enough to delay hatching by a day would result in far more deaths and weaker chicks than continuing as things are. The chicks in the study still hatched on day 21. They aren't dropping the temp to a point they delay development. I think that would run into the opposite extreme and possibly even have some of the opposite problems when you looked at organ development and yolk sac absorption.

If their change in temp is that small I don't think it's even feasible in most people's incubators anyway. I'm happy when my still airs stay between 99-102F. That's a good incubation period if the room and incubator stay stable enough to not go outside that range all 3 weeks. How many can adjust the temp down as they go without dropping it extremely low? If I touch my little giant's thermostat I better be sticking around all day to check it every hour because it's going to be off. The hova I do end up slowly adjusting because it tends to gain in temperature as the weeks go on and it takes a large turn of the dial to bring it down so I'm not concerned about it dropping below 100F. There's no way I could control it down to a degree. That's assuming you have an accurate thermometer too. Most of the thermometers we're using aren't even accurate to the degree and I've been shopping around for something far better than the cheap thermostat/hygrometers everyone always suggests buying. I don't find this applicable outside of large hatchery or scientific studies unless you want to drop the money for a good cabinet size incubator and more accurate thermometer.

 

[walkswithdog]

I did find it interesting. I do like using an internal egg type set up, I've gotten better results since using it and I worry less about air fluctuations. I didn't get much difference using a water wiggler with water inside, over a jar of "Flarp" kids putty. The variation there was less than .3 degrees, and any variation may be that it's time to recalibrate the thermometer - again.

If I had a lot of time and money I'd compare the whole - what to use for inside the fake egg - set of questions. Gel, water, silicone, jello, Flarp, silly putty, etc.

I had noticed that temps creep up overall at the end of hatch. My hatching area in Darthbator is about .5 to .8 of a degree cooler. It's worked well that way. There's no change in the hatching area of the cabinet one, I do increase ventilation toward the end, and it probably does drop it a tad as well, I'll have to check the thermometer's memory...

I like having to think about it more. And don't mind fiddling with things to see if it can get any better. Thanks for the Article.

 

[muddstopper]

I think you are very correct that in most backyard hatches, we simply dont have the proper tools to control our temps and humidity levels to the exacting levels needed to prove or disprove any studies that are found on the internet. Still, these type studies do have merit and gives one pause to think what if. As you mentioned, with the current affordable incubators, any change in temp adjustments would mean babysitting the incubator for hours just to be sure we didnt overdo our corrections. I am hopeing to change that. Take a look at this thread, https://www.backyardchickens.com/forum/viewtopic.php?id=248824.

I dont have this controller in hand yet as we are still waiting on the software engineer to finish writing the software, and then it still has to be tested. While the software is programmable in this controller, its not set up to to raise or lower temps beyond the the initial setting, but is supposed to be accurate to 6/1000 of a degree, and will read temps and humidity in 1/10 increments. Until reading this thread, I thought such accuratecy was overkill. To make this same controller programmable to change desired setting during the incubation period should only take a software tweak, provided the microchip we are using has sufficient memory. If this is the case, you could be able to set the desired temps for incubation periods of 10-12-14 days, or whatever and then have the controller automaticly change to another desired temp for the remaining number of days.

After reading this thread, and the thread by Speckelhen about her egg-o-meter. I am considering also adding a seperate thermostat whereas the sensor would be mounted in a plastic egg for placement in the incubator trays. This would be a inexpensive electronic thermostat and would act as a backup to prevent the actual egg temps from overshooting the desired temperature inside the eggs. We already have this type of thermostat on hand and would only mean incorporating a digital readout so you would know what the actual temperature is. To maintain a high degree of accuratcy, it would also require a slightly more expensive sensor which would probably double the cost of the eggometer thermostat. The sensor in our digital programmable controller cost $35 buying in bulk from the manufacturer, where as the sensors found in your accurite type thermometers only cost a few pennies. Both sensors do the same thing, but being accurate cost$$

I am going to talk to my engineer in Thialand to see what changes can be made without having to completely redesign the controller. Since the first prototype is already built and waiting on software, we probably wont change anything until after testing.

 

[shelleyd2008]

I've never done it with chickens, but I do with quail. They seem to hatch quicker/easier if the temp is lowered in the hatcher, so from about day 14 (for quail, equivalent to day 17 for chickens) until they hatch. I've seem recommendations on lowering the temp for ducks and geese too, and guineas seem to hatch better with a degree lower hatching temp. I don't see why it wouldn't be helpful to chicks.