lymphoid leukosis diagnosis

[slurlinem]

Just out of curiosity, what was the breed of these two? A lot of Legbars seem to be having issues with this. I would love to test my current flock to see who is a carrier and who isn't.

Oh, interesting. I received 30 ”Cream Legbars” (which honestly seem instead to be mixes) and 20 have died. I am new with chickens and suspect LL from all I”e read. My other chickens seem to be fine. I need to get to the bottom of this.

 

[LikeTurkeys]

Oh, interesting. I received 30 ”Cream Legbars” (which honestly seem instead to be mixes) and 20 have died. I am new with chickens and suspect LL from all I”e read. My other chickens seem to be fine. I need to get to the bottom of this.

Sorry for your loss What age did they pass? If they died young (<16 weeks) it's unlikely to be LL.

 

[slurlinem]

Sorry for your loss What age did they pass? If they died young (<16 weeks) it's unlikely to be LL.

One was dead upon arrival (three-day USPS shipping). The death continued at a few days, a couple of weeks, four weeks, six weeks and ongoing. I had one die two days ago, and another today. Now I'm down to 8 of the 30.

The necropsy declared that *because* the few I sent for necropsy all died at 14 weeks, it was more likely Marek's. Faulty reasoning, since that analyst didn't have the entire history.

The BCMs that arrived from the same cooperative (likely a different breeder within the cooperative hatchery) and besides two DOA (again three-day shipping to my remote location), they are all still thriving and healthy. My original (inherited) flock are mostly alive. I did have a couple old gals die, but I now think one was egg-bound. I've another old gal who looks like she is on death's door. I have no idea how old they are, as I got them from the estate of a nonagenarian who passed in our area. (I now understand the folly of taking on such birds and won't repeat that.)

It is my belief that these legbars had LL which was transmitted to them in ovo, from their mothers. I have one more legbar who has had a bum leg for a long time. The other 7 have no symptoms.

I appreciate any thoughts here. Thank you for your response.

 

[LikeTurkeys]

One was dead upon arrival (three-day USPS shipping). The death continued at a few days, a couple of weeks, four weeks, six weeks and ongoing. I had one die two days ago, and another today. Now I'm down to 8 of the 30.

The necropsy declared that *because* the few I sent for necropsy all died at 14 weeks, it was more likely Marek's. Faulty reasoning, since that analyst didn't have the entire history.

The BCMs that arrived from the same cooperative (likely a different breeder within the cooperative hatchery) and besides two DOA (again three-day shipping to my remote location), they are all still thriving and healthy. My original (inherited) flock are mostly alive. I did have a couple old gals die, but I now think one was egg-bound. I've another old gal who looks like she is on death's door. I have no idea how old they are, as I got them from the estate of a nonagenarian who passed in our area. (I now understand the folly of taking on such birds and won't repeat that.)

It is my belief that these legbars had LL which was transmitted to them in ovo, from their mothers. I have one more legbar who has had a bum leg for a long time. The other 7 have no symptoms.

I appreciate any thoughts here. Thank you for your response.

IMO, the Marek's diagnosis is much more likely. LL needs a bare minimum of 14 weeks to show symptoms even if passed in-ovo. Also, the mortality is rarely above 10%, occasionally up to 20% if there are other contributing factors (such as Marek's serotype 2 vaccination), but certainly not >70% like you're describing.

The few that died in the beginning, were likely either shipping stress or another chick killer like coccidiosis.

Your original flock could have been carriers of MD, spreading it to new chicks that have not been exposed yet. Were either your Legbars or BCM vaccinated to your knowledge?

In my experience, Legbars also have a poorer immune response than other breeds, possibly because of their newness to the United States and a limited gene pool. Many breeders have poor fertility, weaker chicks at hatch, and odd 'runts' that don't grow the way they should.

Health and vigor should always be selected for above appearance - something that has not occurred in Legbars as much as it should.

 

[slurlinem]

The Legbar chicks were a mile from the older flock until they were 8 weeks old. They were not vaccinated.

My Maran chicks are 11 weeks old and are in (seemingly) perfect health. They are in an adjacent run, from which I cleaned all litter. I cleaned the house after the Legbars were there.

I know that my 5 marans in the older flock were not vaccinated. I have no knowledge of whether the others were vaccinated.

Thank you for helping me sort this out. I must understand fully.

 

[charlotte-and-the-bees]

The Legbar chicks were a mile from the older flock until they were 8 weeks old. They were not vaccinated.

My Maran chicks are 11 weeks old and are in (seemingly) perfect health. They are in an adjacent run, from which I cleaned all litter. I cleaned the house after the Legbars were there.

I know that my 5 marans in the older flock were not vaccinated. I have no knowledge of whether the others were vaccinated.

Thank you for helping me sort this out. I must understand fully.

Passing comment, but IIRC a number of the studies I’ve read about leukosis are about Legbars. Maybe some increased susceptibility.

We have both Marek’s and Leukosis in our flock. My suspicion based on what I’ve read is the comorbidity occurred due to maternal transmission to egg + the Marek’s vaccination. If anyone’s interested I can track down the source here. In my personal case, it seems like a perfect storm of bad luck. We’re meticulous with their health, haven’t had issues outside of the normal tiny ones you might expect with an immunocompromised flock. In any case, it’s heartbreaking. Just spending time loving on the girls we have.

@slurlinem I would definitely recommend sending off for a necropsy if you can. It’s extra cost I believe for the definitive testing on Marek’s vs. LL, but the vet who did our last necropsy gave the diagnosis based on cell activity. I can share our 2 necropsy reports. The one for ALV had different presentation.