Hello,
My laying hen flock might have a salmonella outbreak. I call it an outbreak, but it's likely going on for at least a year+
I have 2 flocks currently. 1 is my laying hens, coop and run. 2. is meat/replacement chickens out on pasture in chicken tractors. Some of those are the off-spring of the layers, 1 rooster and 1 hen. All the others came from other places (incubated eggs).
Obviously, i have not run any laboratory tests, as even if i knew where, or can afford them, if these tests came positive would likely result in the state having all my birds destroyed, which cannot be, as they are a significant source of protein for us. The original flock was of 21 hens and one rooster, as mixed between 1 and 2 years and a couple 3 years old. now it's down to 16. the rooster and 1 hen, were butchered last week. the other 4 died during the summer, . 1 of the 4 that died, it was found several hours after death so had to incinerate, the other 3 i caught them dead from less than one hour, so were processed anyway to not waste the meat. All of them, had bronzed livers. The one that i processed last week, also had bronzed liver. Overall egg production dropped significantly respective to the previous year, yes, hens get old, but production don't drop 60% or more. other clinical signs i see in some hens, especially two hens, that shit greenish looking, liquid. One of those hens is the mother of my poor house hen (I have a thread about her). The house hen died highly likely of salmonella as well. Even, after a real veterinary gave her real antibiotics, she was ok for one month and then started getting sick again and died. I didn't figure out for a long time how the house got sick in the first place as she was away in the field on pasture and not in contact with her mom or the other hens, so it may even be that it was passed through the eggs.
Other observations, were poor hatch rate, and chicks dying within the first week. Some other hen have a slightly whistle/rale.
I read on poultry dvm, that in such cases, the only solution to eradicate this, is butchering all of the chickens and starting over. Including their off-spring. But the rooster that lived with the hens didn't have a bronzed liver. and the two chickens (a pullet and a cockerel) that are their off-spring and live away from them, are not sick, their shits are fine and they are perfectly healthy-looking, the pullet even lays some eggs.
The source of the infection, is most likely that i ignorantly had their feed outside like everyone else does here, that attracts sparrows in big flocks, it's over 3 months that i have their feeder inside and sparrows have disappeared.
For now, I am taking out hens that are not laying at all (mind that they have artificial lights, so they should lay, and yet i get 3 eggs a day if i am lucky). the other flock remains separate. I feel bad, because every time i look in there i say "look mom, that's the mother of the house hen, i cannot kill her" or referring to another hen that i like cus she's a good layer "but she is such a good layer, i cannot take her out".
Also, how would i go about disinfection. the outside run is just soil. the coop is wood. other than cleaning, scraping I don't have an idea how to actually disinfect the area before bringing new pullets in. It is going to be really cold soon, but i doubt it kills bacteria
My laying hen flock might have a salmonella outbreak. I call it an outbreak, but it's likely going on for at least a year+
I have 2 flocks currently. 1 is my laying hens, coop and run. 2. is meat/replacement chickens out on pasture in chicken tractors. Some of those are the off-spring of the layers, 1 rooster and 1 hen. All the others came from other places (incubated eggs).
Obviously, i have not run any laboratory tests, as even if i knew where, or can afford them, if these tests came positive would likely result in the state having all my birds destroyed, which cannot be, as they are a significant source of protein for us. The original flock was of 21 hens and one rooster, as mixed between 1 and 2 years and a couple 3 years old. now it's down to 16. the rooster and 1 hen, were butchered last week. the other 4 died during the summer, . 1 of the 4 that died, it was found several hours after death so had to incinerate, the other 3 i caught them dead from less than one hour, so were processed anyway to not waste the meat. All of them, had bronzed livers. The one that i processed last week, also had bronzed liver. Overall egg production dropped significantly respective to the previous year, yes, hens get old, but production don't drop 60% or more. other clinical signs i see in some hens, especially two hens, that shit greenish looking, liquid. One of those hens is the mother of my poor house hen (I have a thread about her). The house hen died highly likely of salmonella as well. Even, after a real veterinary gave her real antibiotics, she was ok for one month and then started getting sick again and died. I didn't figure out for a long time how the house got sick in the first place as she was away in the field on pasture and not in contact with her mom or the other hens, so it may even be that it was passed through the eggs.
Other observations, were poor hatch rate, and chicks dying within the first week. Some other hen have a slightly whistle/rale.
I read on poultry dvm, that in such cases, the only solution to eradicate this, is butchering all of the chickens and starting over. Including their off-spring. But the rooster that lived with the hens didn't have a bronzed liver. and the two chickens (a pullet and a cockerel) that are their off-spring and live away from them, are not sick, their shits are fine and they are perfectly healthy-looking, the pullet even lays some eggs.
The source of the infection, is most likely that i ignorantly had their feed outside like everyone else does here, that attracts sparrows in big flocks, it's over 3 months that i have their feeder inside and sparrows have disappeared.
For now, I am taking out hens that are not laying at all (mind that they have artificial lights, so they should lay, and yet i get 3 eggs a day if i am lucky). the other flock remains separate. I feel bad, because every time i look in there i say "look mom, that's the mother of the house hen, i cannot kill her" or referring to another hen that i like cus she's a good layer "but she is such a good layer, i cannot take her out".
Also, how would i go about disinfection. the outside run is just soil. the coop is wood. other than cleaning, scraping I don't have an idea how to actually disinfect the area before bringing new pullets in. It is going to be really cold soon, but i doubt it kills bacteria
Apart from your attachment to some of your birds, there is an argument for not culling those of your flock who appear still healthy and/or got better from it, namely that they may have natural immunity or have better resistance than those who got very sick and died, and you don't want to kill them and lose those good genes. I think endless antibiotics is definitely not the way to go. I will do some reading and thinking and get back to you again later. And meanwhile I'll call up some of BYC's experts who may be able to give you some clear and solid advice 
