Pied Peachfaced Lovebirds

Pied is a mutation that often creates confusion for beginning breeders. Pied acts by removing melanin (a dark pigment) from selected portions of a bird’s feathers and body. The result of this removal is that some or all of the bird's feathers will be either yellow, or a paler shade of green than on a normally colored bird.

The confusion about this mutation arises from the fact that the pattern of melanin removal is different in every bird that carries the pied gene. Some pied birds are almost entirely yellow (photo below), while others might be entirely green. Most pied birds fall somewhere between these two extremes, showing some green and some yellow feathers.

The fact that the yellow feathers of a pied bird may look very much like the yellow feathers of the lutino causes some breeders to assume that the two mutations are closely related. Actually, although both lutino and pied act by removing melanin from the bird’s feathers and body, they are entirely unrelated mutations. You can not produce a lutino by breeding heavily pied birds together, nor can you produce a pied bird by breeding a lutino to a normal green. Their effects are independent of each other.
It is possible for a lutino bird to carry the pied gene, but such a bird will be very difficult to distinguish from a Non-pied lutino. The pied acts by removing melanin from portions of the bird at random, but since the lutino mutation removes all the melanin anyway, there is nothing left for the pied gene to do. The only way to visually distinguish a normal lutino from one that carries the pied gene is by looking at the bird’s forehead. On the non-pied lutino, the transition line between the yellow of the head and the red of the face should be smooth and even. On a pied lutino, the line will usually be jagged and broken.

American pied is a dominant mutation, so any pied parent bird can produce pied offspring, however, the exact mechanisms involved in creating the pattern of "pied-ness" are not fully understood. I believe that pied is caused by a single dominant "trigger" gene, but the exact pattern of its effect depends on many other, ordinary genes. There are an almost infinite number of possible combinations of these other genes, and many of these combinations might cause a bird to not appear pied at all, even if it carries the trigger gene. By the same token, the "ordinary" genes would have no effect on the bird’s coloration unless the trigger gene was also present.
This would explain why pied birds often have similar, but slightly different color patterns than their pied parents. Only half of the genes that determine the pied pattern are passed on to the child from the pied parent. This also explains why pied can sometimes "hide" for a generation or more. Occasionally, a bird which looks like a normal Peachfaced suddenly produces pied young. Such a bird would carry the trigger gene, but its other genes would hide the effects of the pied. The bird’s offspring would have slightly different combinations of "ordinary" genes, which might allow the pied coloration to be seen.

 

 
home madagascar lovebird

green fischer's lovebird

 

Photo credits: Medium Blue Pied and Medium Green Pied lovebirds by Blake Ma; violet pied by Vera Appleyard