I had the best luck with freezing right away. The pullet died in front of me and I did as my vet told me: I held her upside down and rinsed her feathers the wrong way under cold water, then I bagged her and then I double and triple bagged her. I took her immediately to my vet who packed her in one of those styrofoam coolers and dry ice and sent her to rollins.
If a death happens on the weekend, you can do the rinsing thing and then pack it off to rollins on Monday morning, Dr. Aziz will not have a problem with this as long as the bird had recently died before being rinsed and frozen. Its worth the $30 to have them do the necropsy in a lab away from the other birds just in case the cause of death was infectious.
The reason he said that it wasn't worth it to send just one is because there are only a few symptoms that infectious diseases present in chickens. Usually, if you don't see coughing, wheezing, gaping, sneezing, disorientation, lethargy, purple comb and wattles, anorexia (green diarrhea) or neurological symptoms and you don't see more than one death, it is most likely something genetic. I've seen perfectly healthy looking birds fall over dead from heart failure because a dog runs through the yard. Sometimes its genetic or just something unique to one bird.
[/quot. Didn't know about the freezing method. Nobody mention that, they wanted her that day but I live to far for the drive myself. That's good to know, hopefully I won't have to do it. I think mine was genetic because I lost two day olds showing the same symptoms, they were the smallest of the six and the other four died 4-7 months later. Still miss them. It will be a year next week when it all happened.