Incubation is about hatch percentages – and every unhatched egg is an opportunity to review (and improve upon) your management practices Any competent incubator operator should be able to conduct a basic post mortem examination of the unhatched eggs.
Incubated eggs start to go off very quickly – so getting the examination done quickly is a good idea. I use a plastic tray and a knife with a sharp point. I carefully open the egg and pour the contents onto the tray. Comparing the result to an incubation chart will reveal (with reasonable accuracy) the day that any fertile egg embryos died.
OK……now for the results.
Twenty six eggs hatched. One chick subsequently died. Another one made it all the way through the hatch but lacked sufficient vigour to get out of the shell.
Ten of the eggs appeared to be infertile – 10%.
Another couple (2%) had cracked shells and had dried up. We’ll never know whether they were fertile or not. When you consider our egg handling methods, two cracked eggs in a 100 seems reasonable.
Seven embryos appear to have died in the first week or so. Another 10 embryos appear to have expired in the second week.
A total of 7 chicks have been euthanised because of malformed legs. My money’s on diet for this one…..and the embryos that failed to make it through the first and second weeks. You’ve only got to fall short on one amino acid – or vitamin or mineral – and the odds of getting a viable egg widen pretty quickly.
Now for the big one.
A whopping 45 chicks were about to start hatching at the time that we turned the incubator off. Some of them were still alive at the time that I conducted the examination.
This, coupled with the early arrival of 26 chicks, indicates that the incubator was running too hot (probably due to a faulty thermometer) for the entire hatch. That the first chicks were out almost 48 hours before the main body of the hatch suggests that the temperature problem was extreme.
Had all of these chicks made their way out, our hatch would have been around 67 – 68% – about what I’d have expected from my breeders.
Regrettably, the bad news doesn’t end there. Chicks continued to die in the days immediately after the hatch – we now have just 12 of the chicks left.
The chicks that survive the hatch, already traumatised by the circumstances of their incubation, often never quite recover from this setback. Some die and other just fail to thrive. It’s not viable to rear such a small number of chicks and, in most places they’d have been euthanised – but Jan got to them first – so now, they’ll enjoy a comfortable (and expensive) upbringing instead.
There are number of lessons that we can take out of this hatch:
- We need to invest in an accurate thermometer – this is an activity where accuracy (to a half of a degree) is essential.
- Hovabators are great little “fit for purpose” incubators – but they are not idiot-proof.
- There’s a need for far more rigour around incubator operation – particularly making sure that correct water chambers are filled.
This exercise demonstrated that, while incubation is easy enough to do, it requires pinpoint accuracy. Experience, while useful, is nothing without the necessary commitment to an established incubation regime.
Better luck next time.