When breeding Roller canaries it should be the aim of every Roller fancier to raise good birds.  There are those who breed for quality and others are only interested in quantity.  What is the best procedure to attain success?  There are varied views on the matter and every fancier has his own methods.
Some adopt the stock bird principle.  By this I should explain that such fanciers consider the mating of a first class cock with a hen that is herself related to a winner, to be mistaken idea.

Their method is to mate first-rate birds to those considered of average quality.  No doubt winning birds are bred by this system, but when I started the fancy I did so by procuring two high priced – top quality cock birds – and their sisters.
With my first year’s breeding I produced first-rate youngsters.  It must be the aim of breeders, not only to produce winners, but birds that, in their turn, produce birds of equal merit in line breeding.  On the continent we place great value on our hen birds and consider the hen the proper medium to produce winners.  The hen carries in her blood good (or bad) qualities of the song and this should never be overlooked, especially when breeding for schockel.  Neither should it be overlooked that birds must be big, healthy and strong if they are to bring a deep toned Ho-Ho schockel.

In 1948 I bred a young male bird from a cock that was outstanding in Bass, Hollow Roll, Hollow Bell and Flutes.  The father on that bird was without schockel, but the mother was known to be a good schockel hen.  The youngster proved to be outstanding in Bass, Hollow Roll, Hollow Bell and Flutes.  The following year I paired the youngster back to his mother and from this mating I got three cocks and a hen.  These birds were outstanding in five tours only – Bass, Hollow Roll, Hollow Bell, Schockel and Flutes.  They were never out of prizes and gained specials in Hollow Roll, Bass and Schockel.  This satisfied me that the hen carried the Schockel and gave it her sons.  This we call line and strain breeding and call the birds the Hollow Schockel strain.  Birds of this strain sing five tours only.  Next to the Hollow – Schockel strain stands the Gluck strain.  This strain can only be bred for three years without deterioration. After three years we resort to the so-called “blood refresher”.  Blood from the Hollow strain of birds is introduced into the water and gluck strain to prevent the tours becoming flat and hard.  The system of blood refreshing is the reason why some breeders on the continent cultivate two separate strains that they keep entirely separated in different breeding rooms with the young trained in separate cabinets, taking care that the strains do not intermingle in any way. 

Also, after a blood refresher they provide a separate cabinet to house the young cocks from the Hollow Roll to Gluck pairing.  Others cultivate one strain only and make a mutual arrangement with another fancier to exchange birds for a blood refresher. 
To the Glucke strain we also have another distinct division.  Only a few fanciers in Belgium possess birds that are outstanding in Water Roll and Deep Bubbling Water tours.  As a matter of fact we are afraid of the Water tours because we realize that a breeder must be very skillful indeed to be able to breed good youngsters possessing those tours.

The trouble with Water is that is inclined to mix with other tours and ruin them, nevertheless a good deep, mellow water is one of the most pleasing tours of the Roller song.
To maintain the deep, mellow tone in a Hollow – Schockel bird, most fanciers here feed their contest stock on sweet, nutty rape and give each day a little egg food.  The diet is rigidly adhered to during the training months of October and November, except that the cock birds are given, once a week, a little mixed seed comprising Niger, Mawseed, Plain Canary and Oats.  One important thing to remember is that you can nearly always manage tot introduce Gluck into your Hollow Schockel strain by using a good Glucke tutor.

It is not very difficult matter to maintain good quality Schockel in a Hollow Roll strain, but it is extremely difficult to breed and maintain good deep Schockel in a Glucke strain.

From an Article contributed in 1950 by a Continental Fancier.
(Reprinted from the South Australian Roller Canary Magazine 1990)