We keep getting some eggs which are bad....not from being cracked and they aren't old either. I think they are from one of the new hens from the rescue from chicken farms. Never had this before.
It's rare but not impossible to get bad eggs from hens -it's usually a sign of disease or an infection - potentially salmonella which can get into the hens from rodent faeces. From what I understand the egg laying process is slowed when the hen is diseased in any way and the bacteria are transferred into the eggs which can take more than a day or two to form and as such the bacteria have time to turn the egg rotten. Normally you would see a greyness to the raw egg and a merging of the yolk and the white - ... almost as if it had been lightly stirred - there is not always a strong putrid smell that you would get from really bad eggs - just a bit of an 'off' odour to them.
If this is what you are seeing you need to try and isolate the hen that is laying these - not easy but it's essential otherwise you run the risk of other hens being infected.
It can also happen when the hen has developed a tumour which impacts the reproductive tract - again slowing down egg production - very common amongst ex-batt hybrids I'm afraiid - the tend to die quite quickly once the tumour develops - you can often feel a tumour in the abdomen or with a gentle finger up the vent. Also, if the hen has been egg bound at some point and has survived then the reproductive tract can be damaged and produce the same sort of problems.
All the ex battery hens we have rescued have been pretty much clear of bacterial disease and parasites as they are generally laced with antibiotics and antibacterial agents on a continuous basis - takes a while for this stuff to work out of their system but the advantages are that rescue hens are generally pretty healthy - despite looking like refugees from a concentration camp !
More usual explanation is that it's eggs that have been hidden in the straw of a nest box and not noticed for a few days .. the heat of the straw can be enough to 'turn' an egg. Make sure that you are vigilant about egg collection on daily basis.
Also ...be very careful about cleaning any soiled eggs - it's easy with this wet weather for eggs to be muddy if the run is muddy - it's best not to wash them - although it's a temptation - as this removes the bloom on the outside of the egg and any bacteria in the mud (possibly containing poop) can then make it's way via osmosis to the inside of the egg - which will go off pretty quickly - just a day or two sometimes. If you have to clean eggs then I tend to use a dry piece of kitchen roll or one with just a hint of water that is warmer than the egg - and immediately wipe the moisture off with a dry piece of kitchen roll. It's better, really, to clean eggs just before you use them.
I know one backyard hen keeper (stupid woman) who cleaned all her eggs by dipping them in a weak solution of bleach to 'kill the bacteria on the shells' and then complained that 'her' eggs gave all her family the runs whenever they ate them ...she took a bit of convincing that eggs as laid are usually pretty clear of bacteria (I'm NOT suggesting that anyone on here would be that dopey !) - just commenting on the way past ...
Sorry if I'm teaching you to suck eggs ... you may already know some of this.
