Is this duck egg fertilized?

[NimsHouseGarden]

Hi! This is my first time checking for fertilization in duck eggs, my runner ducks have recently started laying again and I'm considering selling hatching eggs. I've witnessed my drake performing his "fertilization ritual", but this is his first year, so he may need some more practice.

I checked two eggs, one I feel pretty confident is not fertilized but the other has a red spec in the center of the white dot. No dramatic bullseye like I've seen in my chicken eggs. What do we think? The second picture I believe is the unfertilized egg.

(Note that I'm using these eggs for baking, so it's resting on chocolate batter)

 

[EggSighted4Life]

I checked two eggs, one I feel pretty confident is not fertilized but the other has a red spec in the center of the white dot. No dramatic bullseye like I've seen in my chicken eggs. What do we think?

The red speck is more an indicator of a meat or blood spot than fertilization.. See the following article.. about chickens but still SOMEWHAT relevant to ducks including cool video on egg formation.. (spots are usually non viable for incubation in MY experience.. will start embryo development but not fully hatch.)

https://www.backyardchickens.com/articles/common-egg-quality-problems.65923/

Before selling any hatching eggs personally.. I run a test batch or several test batches of my own to verify both fertility and viability.

Bullseye can be present even in the absence of males.. parthenogenesis (self fertilization) is a real thing in poultry though *usually* not viable or only male progeny will arise, according to the studies/experiences I've seen/read..

 

[NimsHouseGarden]

The red speck is more an indicator of a meat or blood spot than fertilization.. See the following article.. about chickens but still SOMEWHAT relevant to ducks including cool video on egg formation.. (spots are usually non viable for incubation in MY experience.. will start embryo development but not fully hatch.)

https://www.backyardchickens.com/articles/common-egg-quality-problems.65923/

Before selling any hatching eggs personally.. I run a test batch or several test batches of my own to verify both fertility and viability.

Bullseye can be present even in the absence of males.. parthenogenesis (self fertilization) is a real thing in poultry though *usually* not viable or only male progeny will arise, according to the studies/experiences I've seen/read..

Thank you for your thorough response! I did not consider things that may impact viability. I have someone close by that I will donate eggs to for a test batch before selling! Hopefully I will have some good results.

I did not know about self fertilization! That is wild!