Thursday, June 3, 2010

Fatal Newborn Black Spot

This photo was submitted by a breeder who lost all the chicks in one clutch within the first three days of hatching. A subsequent clutch did not have the black spot and no deaths.

Neonatal Black Spot

Death in nestlings less than five days old, with an enlarged gall bladder appearing as a black spot on the right side of the abdomen, is most likely due to a viral infection with a single stranded DNA virus known as circovirus. Weak chicks that fail to beg for food and show the black spot may appear in nestlings as young as one day old. It is more common in the first and third clutches.

The canary circovirus, known as CaCV is transmitted by "carrier" birds and can be found worldwide. Circovirus, although a different virus, belongs to the same genera of circovirus that cause psittacine beak and feather disease but CaCV is species specific for canaries.

Circovirus in passerine birds was first documented in 1995. It is highly contagious and difficult to kill even with disinfectants and can survive on surfaces for up to six months. Breeding with identified known carriers should be discontinued and the aviary thoroughly cleaned.

Like other virus diseases it is unaffected by treatment with antibiotics. Careful records and selective breeding of birds free from this problem is critical. Working with an avian vet, diagnosis can be confirmed by necropsy or by PCR (polymerase chain reaction) testing for the virus in questionable carriers. Keeping birds free from other diseases will help control the problem. A vaccine is being developed.

Although I have not used Dr. Rob Marshall's KD powder (google for source), theoretically it could help protect healthy members of the flock and strengthen the flock's natural resistance.

4 comments:

Panos said...

I think that s one of the most common causes of death of young birds.

Pierre said...

Have you references on the development of a vaccine for canaries?

Darren said...

Hi Linda
Any developments on a treatment/prevention for black spot ?

Panos said...

Hi,please,i need your help.My one pair of red-black canaries gave me 3 clutches of eggs.The first two were normal,all the babies were ok.At the third,all 5 chicks were born with that black spot.The one died,but the other four live today their 4th day.I hand rear them the first day with creme putting in tylosin,and then till now esb3,giving esb3 in the water of the parents as well.The babies seem to move normally,ask for food...what could i do???I can t take one of the dead ones to a vet,cause its pretty expensive to test and not all vets no about canaries pathology...The other birds i took from that pair,are now fully grown up birds,are they in danger???Are they carriers???Please,answer me to panos0411@yahoo.gr ,it s my e-mail,thank you