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By Miguel Angel Martin Espada (C.N.J. and F.O.C.D.E.
Judge)
Following the famous " Treaty of Roller canaryculture " by Evaristo
Fratantoni, some Spanish authors and , even, some Code of Song mentions
like physiological factors that influence in the tone of the sounds
produced by the canary the following ones:
-The diameter of the bronchi. - The wide bronchi
determine a loss of velocity in the expulsion of the air; on the
contrary narrow bronchi expel air at more speed.
-The length of the esternotraqueal muscle. - When this one is short
disables the elongation of the traquea. A short trachea or that
is not extended with facility elevates the tone of the sound.
-The rigidity in the walls of the traquea. – Rigid walls increase
the tone of the song.
-The position of the larynx. - Since the larynx in spite of not
having vocal cords, can be obdurate or be opened and modify therefore
the tone(*8).
We have already seen that the scientists do not agree totally with
the observations of Fratantoni, but we have believed advisable to
mention them.
Figure 4. Cerebral nucleus that take part in the song function:
Jarvis and Nottebohm, " Motor-driven gene expression ", 1997 The
National Academy of Sciences of the the USA: www.pnas.org
The complex song mechanism that we have just described is controlled
by the central nervous system - see black arrows at 4.a) -, emphasizing
two main cerebral nuclei located in the telencephalon: the High
Vocal Center (HVC) and the Robustus Archistrialis
(RA); that through the neuronal network, the craneal nerve
XII or great hypogloss, located in the rachidian bulb, and of the
hipogloss nerves (also called tracheosyringeal), send their information
to the muscles that allow the production of the sound in syrinx.
Next to these cerebral nuclei we find others, connected of one or
another form with one or both of the main ones. The most relevant
are the Medium Magnocellularis Nucleus (MMAN) and
the Lateral Magnocellularis Nucleus (LMAN), also located
in telencephalon and connected neuronally with the HVC, the first
one, and with the RA, the second; the LMAN plays an important role
in the learning of the song and its motor development. Other cerebral
nuclei of importance in the song are Nucleus Intercollicularis
(ICO), located in mesoencéfalo, connected with the RA and
craneal nerve XII; Nucleus Interface (NIF), connected
to the CVS; the UVA, connected with the CVS; and the
cerebral area X, connected with the CVS. The proximity of some of
these nuclei with the hearing centers of the brain is related by
some experts to the capacity of memorization and learning of the
birds and the later motor development - figure 4.b) -. In fact,
recent studies propose a double mechanism in the memorization of
the songs: the first one consists in the memorization based on the
motor expression of the song (or, which is the same, memorization
of the song through its practice and vocal development, expressed
through the plastic song or review); the second is based on the
storage in the memory of the songs listened to by the canaries.
Both mechanisms interrelate, since a young canary deprived of the
sense of hearing is incapable to develop a normal song, which demonstrates
that the bird must be able to hear its own vocalizations to memorize
them suitably and to compose its song.
Scientists, and among them Fernando Nottebohm (he is the
author of most of the studies on neurological control in the song
of the canary), have demonstrated clear sexual differences in the
size of these cerebral nuclei, specially of the CVS and the RA.
The volume of the CVS and the RA is much larger in males than in
females. Also it has been shown that the size of these nuclei is
directly related to the hormone level in the blood, concretely of
the masculine hormone: the testosterone; to greater hormonal level
greater is the volume of these two cerebral nuclei (* 9). Also it
has been related the size of these cerebral nuclei to the complexity,
variety and duration of the song: to larger volume greater musical
capacity. Although the fact that a canary has a very voluminous
CVS and RA does not imply a better song necessarily, just shows
faculties that the canary may or not develop (* 10).
Returning to the hipogloss nerves, that, as we have seen, are in
charge to transmit the information generated in the brain to the
syrinx, we should explain that the right hypogloss controls the
right part of the syrinx and the same happens with the left. This
explains for the scientists the independent operation of each one
of the syrinx sides.
Be that as it may, the scientists have demonstrated that the intervention
in the song function of each one of the sides of syrinx is unequal,
being on the left side the greater weight to the sonorous production
in the case of the canary and most of passerines (lateral vocal
control with predominance of the left side).
The studies demonstrate that if the nerve right hipogloss is sectioned
the bird only lose some elements of the song, that are replaced
by noises or silences; on the contrary, if the left nerve is sectioned
will disappear most of the song motives. The effects of the section
of the left hypogloss vary according to the phase of the development
of the song in which the bird is:
-Subsong: After a brief time interval, the young bird retakes
his sonorous emissions with normality, the bird replaces the functional
loss of the left nerve with the right. The left nerve does not regenerate,
although there are exceptions that confirm the rule and, luckyly
for us, one of them is the canary. If the left nerve is sectioned
between the 13th and 27th day of life, the
nerve regenerates and both sides of the syrinx share the sonorous
production (there will be sounds emitted by the right side, sounds
produced by the left and others, a third approximately, in whose
production both halves take part).
-Plastic song: The bird remains his entire life in this phase
of the song, without getting to crystallize a song of stereotyped
adult. The canary returns to be an exception, since he is able to
replace the loss of the left side with the right and to get a song
like an adult.
-Stable song: The sounds produced by the left half are replaced
in the song by silences or noises.
In the search of the possessors of the best voices and song aptitude,
the breeders of canaries have selected the morphology of our canaries
looking for certain characteristics present in most of quality singers:
Great head.
Torax amplitude.
Average volume or size
Horizontal position of song (* 11).
The three first morphologic characteristics seems, considering the
mentioned studies, that could be taken like indications of a greater
cerebral capacity, a respiratory system more developed and songs
of average tonalities, more musical, neither too high nor very deep
(* 12).
1,2,3, Conclusions.
1ª) We must look for the perfection of our canaries voices. The
voice timbre must be rich and agreed with the characteristics of
the type of turns that we try to develop in the repertoire of our
canaries. It must have, and be able to develop, a pitch registry
as wide as possible. In addition, it must be able to develop the
song with the appropriate intensity at every moment , with faculties
to modulate it and to grant to the song the most delicate musical
shades. The sounds emitted by our canaries must be clean and clear,
with an excellent diction (must predominate the vowel sounds, more
musical than the consonántic) and with the proper duration
to be able to be appreciated without boring to the listener.
2ª) We will try to obtain birds whose song comes
as close as possible to our ideal form. In order to obtain it, we
must work the innate pattern of song of our canaries by means
of the development of the predisposition to the transmission of
songs based on tours of noncontinuous rate, mainly in the discontinuous
ones; and this is because the predominance in the song of the tours
of semicontinuous rate would confer to the song a precipitation
sensation that would result in a clear loss of musicality.
1.3. - Method of selection. Integral selection of reproducers.
There are different selection methods that the breeder uses according
to the objectives to fulfill. In the present work we will opt for
a method of integral selection, that combines phenotipic
selection, functional and genetic.
Although it is certain that our fundamental objective is the song
and, in addition, a certain morphologic type that favors the song
aptitude, also are of extreme importance the genetic selection in
the creation of a good line of singers and the functional selection,
since without good organic, sanitary conditions and of vitality
a satisfactory development of the song is not possible.
By phenotipic selection we will understand that selection
made based on the perceivable characters by our senses (* 13) and
whose ideal pattern represents the objectives that we have already
seen (* 14, 15).
By functional selection, is understood the made looking for
a correct organic and physiological operation, as well as a perfect
sanitary state in our birds. These characteristics facilitate us
the breeding , since the value of our canaries as breeders is measured
in the functional valuation. As an example we will mention some
of the parameters that are used to measure the functional value
of the breeders in attention to their individual and familiar characteristics:
characters of the new born and index of survival; growth, development,
jump of the nest and age of separation from the parents; vitality;
resistance to the diseases; reproductive behavior, fertility, etc.
The breeding reports facilitate the functional valuation, whatever
more data gather greater will be their utility (* 16).
Finally, we call genetic selection to the made based on the
phenotipic and functional valuation of the ancestors of the birds
object of study and, in addition, in case of adult canaries, of
the descendants (the denominated test of the lineage). Also we can
value the phetotipic and functional characteristics of other related
birds and their descendants (brothers, cousins, nephews, etc.).
We cannot either forget the analysis of the inbreeding degree, distinguishing,
although the reality is more complex, between narrow inbreeding
(between relatives of 1º and 2º degree), average (between relatives
of 3º and 4º degree) or distant (of 5º degree in ahead) (* 17).
We shouldn´t confuse the degree of kinship with the inbreeding rate
or index , this last one is obtained by complicated mathematical
formula, difficult to apply in our case because of the complexity
of the inbreeding crossings that usually we make.
The instrument more adapted to make the genetic valuation of a unit,
a family or a line of song is its pedigree (* 18). Like with the
breeding card, whatever more data contains, more useful it will
be, in opposite case it will be a relation of useful numbers for
the breeder that makes it, but senseless in most of the cases for
others.
The kind of selection within the integral method will often depend
on the aspects to improve in our canaries. For example, when in
our birdroom we begin to have serious problems during the breeding,
due to the decrease in the reproductive capacity caused by the phenotipic
and genetic selection in damage of the functional one, we will have,
under risk to lose all the obtained throughout many seasons, to
focus during years on the functional selection, keeping the birds
with greater reproductive aptitude.
Sometimes, before canaries of unsatisfactory song and with the purpose
of not losing the genetic contribution of a line that has demonstrated
its excellent song value, we will prioritize the genetic valuation
to the phenotipic.
1.4. - Selection of males.
The selection of males must be made, applying what already we have
seen, based on the following parameters:
1º) Absence of song education with masters or electronic means.
2º) Perfection of the voice, to which a certain timbre or color
and a pitch registry are inherent, as a manifestation of suitable
song apparatus and a good state of health.
3º) Dominion of the vocal faculties, made clear through the correct
control of the tone and intensity of the song and a good diction.
4º) Aptitude or musical talent, declared through the slowed down,
rythmical and melodic transmission, as well as the richness in modulations
of tone and intensity and in the different tours or variations that,
to an correct duration, conform the song or songs of the canary.
5º) Emission of a varied repertoire, based on tours of noncontinuous
rate, with plinth in the discontinuous of limitless phonetic text
(flourishes, slow flourishes and cojoint variations) and with the
complement of other tours of noncontinuous rate as clucks and a
minimum touch of watery tours (preferably slow water and semibound
water forming cojoint variations with clucks) (* 19).
6º) Absence in the repertoire of negative tours (scratches, stridencies
and nasalities), degenerative (those that in their phonetic text
predominate phonemes prone to scratches, stidencies or nasalities
such as the consonants Ch, R and G; and the vowels I, E and A, when
they do not go accompanied of other phonemes that smooth their sound);
and tours of continuous rate (* 20) (or at least that does not form
basic part in the structure of the song or don´t serve like support
tours (* 21); when a bird emits a tour of continuous rate of short
duration, at the beginning or at the end of the song, or drags it
at the end of a flourish or finishing a cojoint variation in R,
without reduction of the tours of discontinuous rate, we can tolerate
it, although if in the descendants of that canary the quantitative
presence of continuous rate tours is increased we will have to retire
them of the breeding, since in this case we are in a desviation
of the type of song that we try to obtain). It is preferable as
a breeder a bird of repetitive song and little varied repertoire
but without defects, that another one of rich and varied repertoire
but with defects.
7º) Hierarchic role carried out in the flight cage (bird dominant
or nondominant) (* 22).
8º) A correct morphologic type (great head, toracic amplitude, wide
back, medium size, short legs, smooth, compact and shining plumage...)
and a suitable position of song (horizontal). According to Giorgio
de Baseggio, the male transmits to his descendants, in nine of each
ten cases, the following characteristics:
-Stature (large, medium or small).
-Color and quality of the plumage.
-Bearing (position in which the bird exhibits the harmonic beauty
of its morphologic type in the cage).
9º) Although implicit in the previous points, perfect functional
and sanitary state.
10º) A breeding card and pedigree that guarantees the presence of
all the phenotipic, genetic and functional characteristics exposed
in the previous sections in the ancestors, descendants (if it is
an adult bird) and other members of the family, like guarantee of
its transmission to the following generations.
The knowledge of all these parameters will only be possible supposing
that the birds to select are from our birdroom or from some friend
of total confidence. The rest of the cases we will have to trust
the good faith and transparency of the breeder of which we try to
acquire the canaries.
When choosing a male from another birdroom as important as analizing
carefully its song is the knowledge of the environmental factors
that have surrounded it from their birth to their maturity (absence
of teachers, hearing of the other canaries of the breeder, experience
of the breeder, the premises, feeding, etc.) and, of course, of
the breeding card and pedigree (with examination, if it is possible,
of the song and the phenotype of the birds (* 23) that in those
doccuments appear).
We should never select like reproducer a male without total guarantees
of its genetic value, even if its song is excellent. We have to
consider that if it has been educated with teacher we have no guarantee
of the type of song that the bird is predisposed to (some lines
have been selected by its capacity of copy and can be educated with
birds from other line of song(* 24)).
1.5. - Selection of females.
Selection of females is more complex and difficult than males for
an obvious reason: the male sings and we can appreciate his greater
or smaller song aptitude, but the female doesn´t. Let us see the
selection parameters, in many cases identical to the already seen
for the males.
1º) Absence, in the birdroom, of song education with teachers or
electronic means.
2º) Selection of the females based on the males already selected,
two by each male (it is recommendable for the beginner to acquire
males and females from the same breeder, considering always the
breeder´s advise(* 25)).
3º) Females must be from the same line or song direction than males.
When valuing song compatibility of male and female we will consider
similarities in the apparatus of phonation, that determines the
voice, or timbre of voice, on one hand, and of innate song pattern,
that determines the type of tours that the canary is able to emit,
on the other hand. In order to study the compatibility of voices
in the case of the female, we will observe in the first place the
voices of its brothers. In order to study the compatibility of its
innate pattern of song we will analyze and value the song of its
father and brothers or stepbrothers of father, considering the the
parameters 2º to 7º of the previous point (* 26).
4º) Valuation of the quality and sonorous complexity of the calls
or other sound manifestations, like indicative of the phonic apparatus
qualities
5º) A suitable morphologic type (great head, torax amplitude, wide
back, medium size, short legs, smooth, compact and bright plumage...).
We will use the females to correct the morphologic deficiencies
that the males show and as a way to balance the song phenotipic
selection made in these, in damage of the morphologic phenotipic
selection. According to Giorgio de Baseggio, the female transmits
to its descendants, in nine of ten cases, the following characteristics:
-Type.
-Head.
-Form.
-Physical Constitution.
6º) Perfect functional and sanitary state. From the point of view
of the functional valuation it is of capital importance to know
the reproductive qualities of the females of the line or family,
because if they are bad breeders we will save unnecessary sufferings
using foster mothers.
7º) A breeding card and pedigree that guarantee the presence in
ancestors, descendants (if it´s an adult bird) and other family
members of all the fenotype, genetic and functional characteristics
exposed in the previous sections , like guarantee of their transmission
to the following generations.
Notice also the considerations exposed in the previous point when
speaking of the difference between the selection of own and other
breeder birds, as well as the precautions to take in this last case.
1.6. - Selection of foster mothers.
As we will see , the best practice in song canaryculture it is to
leave hens alone feeeding the youngsters (to avoid copy risks).
This practice demands a great effort to the female and determines
that the breeder must be sure to have hens able to take good care
of the chicks by themselves
In order to finish this chapter we will make reference to the selection
of foster mothers, essential point in the agenda of every high selective
canary breeder.
Three are the reasons that justify this affirmation:
1º) The females that do not feed the youngters will be able to do
more laying (although it is not recommendable more than four per
year and resting a minimum of two weeks between layings) and to
extend their reproductive life (* 27).
2º) The phenotipic and genetic selection usually causes the forgetfulness
of the functional selection, with the consequent decrease in the
reproductive capacity of our canaries.
3º) When we´ve got a high quality line of canaries we cannot leave
the success in the breeding just on females able to feed properly
to the youngsters; some great quality hens probably will not be
able to do it.
If we do not have a familiar trunk with outstanding hens by their
reproductive qualities that can be selected to make the functions
of foster mothers, we will have to look for another fanciers hens
able to do that role.
The more selected it is our line and greater is in it the inbreeding
rate, more neccesary becomes the use of foster moms. Their number
never is sufficient, because even if we´ve got many of them, throughout
the breeding season, probably we would wish to have more, as there
are always some hens that don´t behave as we hope (even if a female
breeds properly a year this does not mean she´ll do the same the
following , in fact females that have bred 7 or 8 birds, if don´t
not receive the needed attentions during molt and winter, probably
will not raise any birds the following season).
Notes:
8 Fratantoni also mentions the role of neurohormonal
nature impulses, that we will talk about ahead.
9. In the first days of life the volume of the CVS and the RA is
small, without significant differences between males and females.
With the pass of the days and as increases the level of testosterone
in the blood, the volume of these nuclei in the brain of the males
will increase and at the same time will evolve the sonorous manifestations
(calls, subsong and , after this, plastic song). With the beginning
of the molt , the growth of the nuclei stops, coinciding with a
slope in the hormonal level in blood. Finalized the molt the growth
continues until becomes stabilized when the maturity of the song
or stable song is reached. Every year, the adult birds will repeat
the process during molting: low level of testosterone in blood,
diminishes the volume of CVS and RA and the song of the canary goes
back to the phase of plastic song. Until the molt does not finalize
and the testosterone level starts to raise, along with the volume
of the cerebral nuclei, the canary does not return to a stable song.
This it is the reason why adult males copy and even completely replace
his song during the molt. The importance of hormones in the song
is so relevant that by means of the injection of testosterone in
hens scientists have been able to cause them the emission of clear
masculine songs.
10. Let's imagine a canary that has copied of another one a simple
and monotonous song, in spite of having faculties to have developed
a rich and varied repertoire.
11. Canaries that sing on vertical position usually emit their songs
in a more strident and precipitated way. For this reason it is recommended
to raise the perches of the show cages , so inadequate positions
of song can be, at least, partially corrected
12. Scientists have shown the relation between the size of the bird
and the tonalities of their song. Large canaries usually sing in
deeper tones.
13. In this way we include in the phenotype the visual characters
and also the song.
14. Let's remember that the phenotype is the result of the action
on the genotype of the environmental factors, in ample sense
phenotype = genotype + environment
Another form to express previously this is reflected in Walter´s
triangle, in which an individual is represented as an equilateral
triangle whose base is the hereditary patrimony and whose sides
are the feeding and the environment respectively (we include the
feeding among the environmental factors).
15. The judgment form of a bird song , unlike in other specialties,
has a relative value, since it reflects the valuation of the song
emitted during the fifteen or twenty minutes that the judgment lasts;
a canary does not sing exactly twice in the same way and its quality,
although it did not vary the repertoire, is not constant. We have
to be conscious that the algid period, qualitatively, of the song
is proportionally very short within the vital cycle of a bird (development,
maturity and declivity) and that many birds do not arrive at the
contests at the optimal moment of their song (by immaturity or exciment).
The duration of the period of song fullness will be one of the parameters
that we will have to work on. In spite of the saying, for a beginner
a judgment form emitted by a judge of recognized technical solvence
can be a useful instrument to replace his deficiencies with respect
to the song of the race, more by knowing on what tours the canary
bases its song that by the points that can have.
16. View breeding card example in the ANNEX.
17. We distinguish straight or linear kinship (the existing between
individuals that descend from others: greats-grandfather, grandparents,
parents, children...) and collateral kinship (the one of individuals
that do not descend from others but that they come from a common
trunk: uncles, cousins...). In order to measure the degree of linear
kinship of a bird with another one, we will count the number of
generations that there are until the ascestor or descendant which
interests us, excluding the generation of the bird from we started
off. In case of collateral kinship, we will count until the closest
common ascestor the next one and then we will continue counting
until arriving at the second bird, the resulting number will be
the kinship degree. Let us see a practical example:
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2º
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`A X B
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`C X D
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1º
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`E X F
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`Z
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Being Z the exemplary object of study, and E and F, its parents,
will have a degree of linear kinship of 1º degree, whereas to A,
B, C and D, the grandparents, will have of 2º degree.
Let us see another genealogical tree now:
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2º
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`A X G
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`H X I
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1º
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`J X K
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Y
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Is there any kinship between Z and and Y and in case that there
is in what degree? Well, checking the pedigree we see that both
have a common ancestor, the male A, common grandfather (they are,
therefore, cousins brothers, since their respective fathers were
stepbrothers). Following the rules exposed we see that from Z to
A there are two degrees and from A to Y two more, therefore between
Z and Y exists a collateral kinship of fourth degree.
18. View pedigree card of four generations in the annex. After having
used cards of five and six generations, we have reached the conclusion
that the most practical cards are those of four generations; since
from the fifth generation the statistical percentage of the genes
of each one of the birds that form it is reduced to the minimum:
1ª Generation: parents, 50% (1/2).
2ª Generation: grandparents, 25% (1/4).
3ª Generation, greats-grandfather, 12.5% (1/8).
4ª Generation: greats-greats-grandfather, 6.25% (1/16).
5ª Generation: 3,125% (1/32).
By that reason when a racially mixed bird, product of the crossing
between two different races, is crossed with birds of one of the
two parentales races during other three generations has been considered,
in principle, pure bred, since the percentage of genes of the race
in the fourth generation is of 93, 75%.
- G1. A X B = C (50% A / 50%B).
- G2. C X A = D (75% A / 25% B).
- G3. D x A = E (87, 5% A / 12.5% B).
- G4. E X A = A (93, 75% A / 6,25%B).
19. View our ideal form.
20. The absence of continuous rate tours in the song of our canaries
is not capricious; we already saw the mutual incompatibility between
the continuous rates and the discontinuous ones. The culture, development
and qualitative and quantitative improvement of the tours of discontinuous
rate implies the progressive elimination of all vestige of continuous
rates in the song of our canaries.
21. Tours of continuous rate that arise in the song of our canaries
at the end of the phase of plastic song or maturation (in the month
of October and begining of November) are pardonable, but those birds
that emit them from the beginnings of their song ( two months old)
sounds of continuous rate demonstrate a genetic predisposition for
the transmission of such and they do not have to be used like reproducers,
except for causes of greater force.
22. As we will see at its moment, the role played by a canary in
the hierarchic scale of the flight cage is very important, since
if this one was the dominant bird, its subsong will have been taken
like reference by the hierarchically inferior males. With this dominant
birds we have an extra guarantee of the heredability of their song
that has not been copied at all . Their non dominant brothers have
contributed with less information to the development of the song
of the flight . For that reason it is important to know what male
takes the guideline of each flight, since, even if their song is
of a little bit less quality, it has been developed mainly just
by himself
23. We know that most of us have not enough room in our birdrooms
to take care of the song of our adult birds. Sometimes we must even
ask relatives or friends to keep the adults for us, knowing that
they have common canaries that for sure will affect negatively to
the song of our birds during the molt. Yet even in the case of adult
canaries with a very degenerated song we often can get some information
about the type of song that they used to have when we selected them
as breeders
24. When birds from a certain line of song are trained with a teacher
from a differnet one, they usually don´t assimilate in a right way
the song of the teacher, since their apparatus and their innate
model of song haven´t been selected in the same song direction that
the teacher.
25. An advice: do not begin with more than two males and four females.
26. Although the song is determined by sex (on the basis of hormonal
secretions), we start from the hypothesis, and so subject of discussion,
that the genes that govern the innate pattern of song are bound
to sex (to chromosome Z), therefore the female would contribute
to its children the information contained in the inherited masculine
sexual chromosome of its father. However, the song is a character
of Quantitative Genetics in whose manifestation take part multitude
of genes, many of which are not related directly to the song function
(like which they determine the different morphologic characters
that we have seen that they influence of one or another form in
the sonorous transmission).
27. A female that feeds the youngsters usually has a reproductive
life of three or, in the best of the cases, four years. The females
that do not feed, if they are properly treated, can be used five
or six years (I have even seen nine years old hens breeding).
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