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Observations on Fleece Color
Inheritance Patterns
by George Davis, MS
Color is one of the most important characteristics of alpacas because it can
have a major influence on the end use of fleece. During the seven years in which
significant numbers of alpacas have been in New Zealand, the preferred color has
changed. Initially, the strongest demand was for solid whites, but in the past
two years, black has become the most sought-after color. white fiber allows the
greatest opportunity for dyeing and so has been important where alpaca fiber is
traded as a commodity, but in New Zealand the craft industry uses most fiber in
its natural state. Multicolor (paint) alpacas are popular as novelty animals,
but their fleeces require careful sorting or blending, and they are not as
popular as solids in stud flocks.
Assigning color to an alpaca is subjective. while disagreement over white or
black is unlikely, a range of interpretations on the intermediate shades is
common. Defining standards and consistently interpreting the differences between
light, medium, and dark shades of fawn, brown, and gray are difficult; add to
these variations picturesque descriptions such as caramel, champagne, cream,
apricot, peach, strawberry, coffee, and rose gray, and the potential for debate
is almost limitless. For example, between the various hues of fawn and brown is
a range from off-white to very dark brown. In classifying shades, the problem is
where to draw consistent lines between them. In alpaca fleeces as in human hair,
the shades of gray depend on the ratio of pigmented to unpigmented fibers. The
fiber mills in Arequipa, Peru, have devised detailed color charts to help
standardize color identification, but it is never done with 100 percent
precision.
The New Zealand alpaca flock is based on Chilean bloodlines, and the imported
animals were of a wide range of colors. The AgResearch alpacas descend from 137
females and 17 males imported in 1989 and 1990. From these and subsequent
generations we have 438 births representing progeny of 31 males and 216 females
with full pedigree records. Pen matings have ensured accurate identification of
sires. This data set is small for the purpose of establishing the inheritance of
coat color in alpacas, but it does give some preliminary indication of the
outcome of matings from the somewhat heterogenous Chilean alpaca population.
Humberto Gandarillas proposed that four genes control coat color in llamas
and alpacas,
1 and among his conclusions was the proposal that colored
is dominant over white, brown is dominant over black, and solid is dominant over
spotted combinations. More recently, Julie Koenig has presented a more detailed
model involving eight genes
2 that contradicts that of Gandarillas in
relation to the inheritance of brown and black, and white and color, proposing
instead that black is dominant over brown and that white is dominant over color.
The Australian Alpaca Association, which recognizes twelve colors, is
establishing a very large database of color inheritance. The "1995 ARSC
Advisory Committee Final Report and Recommendations"
3 also
suggests that The Alpaca Registry, Inc., use its database to further
understanding of color genetics. Records from these two large registries should
utlimately resolve some of these issues, but accurate pedigrees and consistency
in assigning color will be essential to refine the inheritance models of
Gandarillas and Koenig.
The assignment of color in the AgResearch alpacas has been based on the main
body (ignoring head, anterior neck, and socks). Colors were simplified to white,
brown, black, gray (mixed white and black fibers), and roan (mixed white and
brown). The multicolors were described as piebald (white and black patches) or
skewbald (white and brown patches). Although this is a very simplistic approach
that ignores the subtle shadings of brown and fawn, it does ensure consistency
in assigning an animal to a particular group. Coat color was determined at skin
level to avoid mistakes in identifying color changes caused by weathering
effects.
Table 1 summarizes the coat colors resulting from the AgResearch matings.
These data are from a small sample of the Chilean alpaca population so they must
be interpreted with caution. However, these bloodlines have had significant
influence on the present New Zealand population, and the outcomes of these
matings are likely to be quite relevant in the future. where there have been
many generations of selection for specific colors (white or fawn, for example),
genetic variation in color in likely to be much less than otherwise, and
therefore the color of progeny is more predictable.
Table 1 Coat Colors 437 Progeny with Known Parentage
| Colors of Parents |
Colors of Progeny |
| Parent A |
Parent B |
White |
Brown |
Black |
Gray |
Roan |
Piebald |
Skewbald |
Totals |
| White |
White |
51 |
10 |
0 |
0 |
0 |
8 |
12 |
81 |
| White |
Brown |
15 |
29 |
3 |
2 |
2 |
2 |
10 |
63 |
| White |
Black |
4 |
5 |
6 |
0 |
0 |
1 |
1 |
17 |
| White |
Gray |
1 |
2 |
5 |
2 |
0 |
0 |
2 |
12 |
| White |
Roan |
3 |
5 |
0 |
0 |
0 |
0 |
0 |
8 |
| White |
Piebald |
11 |
0 |
3 |
0 |
0 |
5 |
6 |
25 |
| White |
Skewbald |
17 |
3 |
0 |
0 |
1 |
1 |
12 |
34 |
| Brown |
Brown |
2 |
52 |
14 |
1 |
0 |
1 |
6 |
76 |
| Brown |
Black |
1 |
11 |
14 |
1 |
0 |
3 |
0 |
30 |
| Brown |
Gray |
2 |
2 |
3 |
3 |
0 |
1 |
1 |
12 |
| Brown |
Roan |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
1 |
| Brown |
Piebald |
1 |
1 |
0 |
0 |
0 |
1 |
0 |
3 |
| Brown |
Skewbald |
0 |
0 |
0 |
0 |
0 |
0 |
2 |
2 |
| Black |
Black |
0 |
2 |
19 |
0 |
0 |
2 |
3 |
26 |
| Black |
Gray |
1 |
0 |
7 |
1 |
0 |
0 |
0 |
9 |
| Gray |
Gray |
0 |
2 |
5 |
9 |
0 |
0 |
0 |
16 |
| Gray |
Roan |
0 |
2 |
0 |
0 |
0 |
0 |
0 |
2 |
| Gray |
Piebald |
1 |
0 |
1 |
0 |
0 |
0 |
0 |
2 |
| Gray |
Skewbald |
2 |
0 |
0 |
0 |
0 |
0 |
0 |
2 |
| Roan |
Roan |
0 |
1 |
0 |
0 |
2 |
0 |
0 |
3 |
| Roan |
Piebald |
2 |
4 |
0 |
0 |
0 |
1 |
0 |
7 |
| Roan |
Skewbald |
2 |
4 |
0 |
0 |
0 |
0 |
0 |
6 |
| Totals |
|
116 |
136 |
80 |
19 |
5 |
26 |
55 |
437 |
The observant reader will notice that the table lists 437 animals, not 438. A
skewbald female that had been mated by a white male produced a brindle cria
(black and brown mixed in blotches throughout the fleece), which defied the
simple classification system used in the table.
Where both parents were black (26 progeny), 73 percent of the offspring were
black and only 8 percent brown; where both parents were brown (76 progeny), 68
percent were brown and 18 percent black. If brown were completely dominant over
black, no brown progeny would be produced where both parents were black, whereas
if black were completely dominant over brown, there would be no black progeny
where both parents were brown. Our flock records do not quite fit either model,
although they are closer to the dominant brown model.
In one instance, a cria was born brown, but when the fleece was about 2.5
centimeters (1 inch) long, it suddenly changed to black, leaving a distinct band
throughout the fleece. The cause of this dramatic change is unknown. Many genes
have been proposed for coat color in alpacas, but no one has ever suggested a
chameleon gene!
Mating two white parents (81 progeny) resulted in 63 percent white and 25
percent multicolor. where only one parent was white (159 progeny), the
percentage of whites dipped to 32 percent and multicolors remained at 25
percent. White progeny from 132 matings in which the parents were either black
or brown were uncommon (2 percent), which supports the proposition that white is
dominant over colon If white were recessive, many black or brown alpacas would
be likely to carry one white copy of the gene, so that when they were mated
together, white progency would occur in about 25 percent of births.
We have not used multicolor sires and therefore have no information on the
outcome of matings between two multicolor parents. Mating a multicolor with
white or brown (64 progeny) produced 42 percent multicolors, but mating a
multicolor with gray or roan (17 progeny) gave only 6 percent multicolors. Where
a gray or roan sire was used over any color (80 progeny), the incidence of
multicolors was only 6 percent.
In summary, although the inheritance of coat color in alpacas is complex,
mating like with like - both animals of the same color - seems the best approach
to obtain white, brown, black, gray, or roan. Nevertheless, for many alpaca
generations to come there will continue to be enough mysteries to ensure that
selecting for color can be either a joy or a frustration.
About the Author
George Davis has published 130 papers on sheep, cattle, and alpaca breeding
and production based on twenty-five years' experience in New Zealand and Korea.
In 1994, he received the prestigious McMeekan Memorial Award from the New
Zealand Society of Animal Production for outstanding service to agriculture. He
has been a speaker, primarily on subjects related to fiber production in
alpacas, at several Australian Alpaca Association national seminars and was a
guest speaker at the 1995 AOBA conference.
- J. Tillman, "Coat Color Inheritance in Llamas and Alpacas," Llama
World 1, no.3 (1983): 4 - 7.
- J. Koenig, 1995 Conference Notebook, Alpaca Owners and Breeders
Association, 4th Annual Conference, June 7-11, Estes Park, Cob.: C49#54.
- "1995 ARSC Advisory Committee Final Report and Recommendations,"
The Alpaca Registry Journal 1, no.1 (Winter-Spring 1996): 13-26.
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