Hello, new to hatching. Set of 6 Aylesbury ducks now on day 27 of incubation. Two moving about but can’t hear any cheeping and no pips as yet. Slightly concerned about this egg, large piece of shell had come off (pointy end- pic attached) morning of day 25, left him alone but membrane now appears a browny yellow and dark bruise-like patch has appeared at opposite end. No movement. Is he still alive/how do I check/if dead or infected will he affect the other chicks? Many thanks!