Sunday, 26 February 2017

What To Do When Egg Candling Is Not An Option

New 2017 Farm Logo
Our farm has been involved with emus since 2009. After a year of intense research we bought our first emu eggs from a farmer in Oregon. It has been an exciting and rewarding journey. However not for the faint of heart. Many challenges and setbacks with incubator failures, threatening wild wolves, searches in vain for appropriate processing facilities, strained bank accounts labouring under pen and housing construction costs, inefficient feed bills as our herd (mob) grew to an economical size........list is long but nothing new to livestock farmers starting out. Now we are feeling the confidence of getting over the steep
learning curve and creating a 
manageable business plan.

Dry conditions bring deer & predators


So last year (2016) we took the advice of the sages and gave a year's rest to this blog diary. You might say we took a sabbatical (from Wikipedia: the sabbatical year or shvi'it {Hebrew: שביעית‎‎, literally "seventh"} is the seventh year of the seven-year agricultural cycle) to recharge our batteries and provide ourselves with some distance from the detail.



We have now been able to percolate the big picture highlights as we see them. This year's blog will continue in it's effort to help start-up emu farmers by consolidating and linking to the chronological detail of past posts. So with that in mind we will start at the beginning....with the egg and what we have learned about how to successfully incubate them as they are large, thick shelled and opaque to a most candling devices. (click here to see earlier post on this topic)

The techniques of artificial egg incubation started in the late 1800s and have been refined to support a huge world wide industry of big (and bigger) and smaller hatcheries. There are only a few basic principles (beyond the given of cleanliness) in managing egg incubation: temperature, humidity, fresh air and egg turning.


Optimum temperature across most birds is 36C (96.8) - 38C (100.4F). After start of season calibration with a good thermohygrometer like one made by Oakton you should be able to trust the dials on your incubator. Some people test several times during the season. Embryos grow from the consumption of nutrients in the yolk and albumen. Waste products (water and carbon dioxide) are expelled from the shell during this growth and consequently room is made for the absorption of oxygen through the shell pores (30,000 in an emu egg) (most concentration at the air sac end of the shell). This mechanical process is facilitated by the relative humidity conditions in the incubator usually run at about 30% RH for emu. This elimination of waste products can be measured as egg weight loss and is consistent for all birds at 15% of the original weight over the course of incubation regardless of egg size and incubation duration. As the embryo grows the air space increases to roughly 15% of the volume of the egg and will be the chick's first breathing source during hatch.

To supply oxygen to the embryo and remove carbon dioxide from the egg shell an outside fresh air system needs to be provided to the incubation room (and hence the incubator) and an accompanying outside exhaust. In the early stages of incubation an extensive vascular membrane (CAM) is set in place by the embryo to facilitate this gas exchange through the shell pores. To ensure the effectiveness of the CAM the incubating emu egg needs to be turned through a full 180 degrees at least 3 times per day. Without proper turning parts of the vascular system may be cut off and die with the weight of the growing chick

Now the principles of temperature, fresh air and turning are properly taken care of. What is left is to manage the speed at which the chick grows through the incubation period. This, as we said, is determined by egg weight loss and in an artificial setting managed by the farmer. The chart below has evolved over our years of hatching emu eggs and has been a confidence builder for us as we deal with the eggs that don't conform to the norm (lol). We hope it will be useful for you as well.       
  (for a larger view click here to our bcemufarm.ca page)
 
  
Small print inside egg reads: Chick grows as yolk and albumen are taken in.

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