I was experimenting in a way with my pure NH hens for this hatch. The question seems to often come up "how long do I need to wait before the eggs are purebred?" and I've seen every answer under the sun, but the one that predominates is that the hen will use the "freshest" semen to fertilize her egg. So, I put a trio of NH's in a pen together and started collecting their eggs from the first day. The only other roosters here are Barred Rocks so at hatch it is easy to tell which rooster fertilized the egg. Black chick means BR is the daddy, orange chick and it was the NH. I dated all the eggs so I'd know for sure. The earliest eggs by date (not by hatch order) all hatched out black chicks It appears that the hens' eggs did not start getting fertilized by the NH rooster (even though I saw him mate them immediately they were penned together) until about day 5. My point is, if you only separated your pure Sussex hens for 2 days, there is no guarantee who fertilized their eggs.
Awesome scientific study on the purebred vs. cross bred fertility!!!
I didn't care which rooster fertilized the hen's eggs, on the Sussex eggs that I pulled. I just knew the hens were my biggest girls - absolute MONSTER hens - and I was hoping that maybe I'd get a nice big-sized rooster with color out of "whatever" roo mated them. All I have in the barn right now are colorful Aloha boys. None are big, but all have great spotting! So, I didn't really care who the daddy was, only that with Mom being so enormous, that I'd have a chance for a rooster with some decent size and (maybe) some OK spotting. So right before I went to set a batch of "keeper" chick eggs, I pulled my two BIGGEST pure Sussex girls so I could make sure I raised their chicks with my "keeper peepers" to see how they turned out.
It is just weird to me that all three of the Sussex eggs by two different hens did not hatch, even though the other eggs set on the same date - did hatch? The entire batch of chicks had a fantastic hatch rate, and the Sussex eggs were fertile and developing as well. But then, no chicks on the Sussex eggs? Very weird. I had near 100% hatch rate but the Sussex egg were all failures.
I'm getting ready to pen all of my big fat Sussex hens together and put various small colorful Aloha roos with them in rotation, so we'll see if this was a random fluke or a trend?
My frustration lies in that every time I try to use a BIG hen or rooster, it seems I have issues! LOL. I've had problems like this before. Like one year, I only kept ONE colorful Aloha rooster, and I only had about 3 big hens. I had about 10 small Alohas. So the rooster had a LOT of girls to cover.
The big hens laid very big eggs, vs. the smaller hens, so I could tell the huge eggs were the big hen's. When I candled the eggs, however, the BIG eggs were always blank. The rooster had a wide selection of hens, so he favored the easier to mount small hens. He just skipped the big girls, leaving their eggs sterile. Eventually, I penned him with the big girls alone and finally got a few eggs. But by then, I'd hatched out a zillion chicks by the little hens. So by sheer numbers, the small girls won out that breeding season. LOL.
It's just funny to me how much the little chickens tend to biologically have the advantage over the big heavy chickens!