Alpaca Breeding for Genetic
Gain
Mother Nature was surveying the long Andean backbone
of South America. She watched the Vicuna in Peru run like the wind and
the Guanacos of Patagonia roam the fertile plain. Everything was beautiful.
Her plan was working. But , as she looked up the coast to North America,
trouble was on the horizon. The first men were making their way down
the continent. Soon they would discover the wild camelids.
Mother nature hatched a plan. She encoded the Vicuna with a blueprint
for the alpaca. She could see a time when certain Vicuna would evolve
and become known as alpaca. The genius of her vision was alpacas, with
fleece as soft as an angel's wings. No one would kill these docile,
productive creatures. The wild vicuna would not be necessary for their
pelts and could live in peace. As an extra measure of insurance, Mother
nature added a few chromosomes for density and fineness for the alpacas'
new owners to uncover.
The Incas unlocked nature's alpaca plan and prospered mightily. Alpacas
with fine dense fleece were grown in abundance, supporting their entire
kingdom. Then came the Spanish. These were men that Mother nature apparently
didn't contemplate. They wreaked havoc. Alpaca breeding became disorganized
and the animals' fleece became hairy as a result of crossbreeding with
Llamas.
But Mother natures genius is still locked inside the alpacas. Every
once in awhile a cria is born with fleece finer than angel's hair. We,
as an industry, can again solve natures puzzle. We need to get organized.
We need a plan.
The traditional livestock industry employs a number of breeding systems
which can be successfully employed in raising alpacas. The systems discussed
below provide an organized approach for alpaca breeding that can be
useful to large and small breeders. It is also important to understand
how genetics, heritage, and the environment can influence the quality
of our bloodstock. Understanding which genetic traits are present in
the alpaca you are considering for purchase and what selection criteria
to employ for individual animals can be valuable to both beginning and
experienced breeders.
The business plan at Northwest alpacas is based on breeding alpacas
which produce low micron fiber in high volumes. This strategy should
enable us to compete effectively at several levels: 1) The textile market,
which pays a significant premium for fine fiber; 2) With sheeps wool,
the bulk of which is coarse; 3) The South American alpaca fiber producers,
who select their breeding stock and sell their fiber based on volume,
not fineness; and, 4) With other ranches selling bloodstock that produces
alpacas having coarse hair and lower fleece weights. We are also looking
to produce a uniform, "typey" alpaca which does well in the
show ring. Alpaca fiber is known as a specialty fiber. In fact every
fiber, other than sheeps wool, is known as a specialty fiber. Wool is
grown world wide in huge quantities -- 432,000 tons in 1994 alone (source:
Wool International). Specialty fiber production totals only 142,000
tons per year. Of this, only 4,000 tons are alpaca. Scarcity or rarity
is one of alpacas' major competitive advantages.
R.C. Couchman, a well known Australian fiber expert, authored an extensive
series of articles for Llama Life about alpaca fiber. He made the following
point many times over -- "Fineness is what specialty fiber is all
about." Alpacas shouldn't compete with sheep, which produce large
volumes of coarse fiber, when they have an excellent potential to produce
fine, soft fiber and receive a significant price premium upon sale.
Fiber density on the animal or the weight of a shorn fleece is an important
component of an alpaca's value. Every alpaca costs about the same to
maintain. An animal which produces twice the fleece in a given period
will be twice as valuable, all other things being equal.
BREEDING SYSTEMS
Ranchers who breed a wide variety of domestic livestock employ a large
number of breeding systems to improve their stock. I have summarized
these different systems below:
Random Mating: This is the simplest mating system;
it means that any male in a mating group has an equal chance to mate
with any female in the same group. In the simplest form of random mating,
also called "syndicate mating," a group of males is put with
a group of females; the male parentage of offspring is then unknown.
Like to Like: Genetic Inbreeding: Animals related by
ancestry are mated, such as father-daughter, half-sibs, etc. Inbreeding
is used in an attempt to capitalize on an individual animal's superiority
and to develop inbred lines for later crossing, to exploit heterosis
(hybrid vigor).
Genetic Outbreeding: This involves the deliberate mating
of unrelated animals. It might be used to avoid or correct the deleterious
effects of inbreeding, or in the crossing of populations to introduce
genes (migration) or to exploit hybrid vigor. Like to Like Mating Assortative
- Phenotypic: This involves mating animals with similar characteristics;
if sires and dams have been selected on high fleece weight, for example,
there might be further subdivision so as to mate sires with the heaviest
weights to dams with the heaviest weights, and so on down the line.
Unlike Mating - Disassortative - Phenotypic: Here animals
with dissimilar characteristics are mated; in practice, it is sometimes
called "corrective" mating. For example, dams with coarse
fiber might be mated to sires with low micron counts, to obtain cria
with finer fiber. This, of course, assumes that the effects of the genes
are strictly additive.
The American alpaca gene pool is small by any standard, this makes inbreeding
an inefficient method of improving herd quality. Line crossing is also
difficult because there are few, if any, established bloodlines. Random
mating is likely to have little qualitative gain, especially since rigorous
culling is not practiced due to the small general herd size. Unlike
mating is most effective when trying to eliminate undesirable traits
within a population. Genetic Outbreeding is the norm on American and
Australian alpaca ranches.
Northwest alpacas has organized their breeding program around the concept
of like to like phenotypic mating with the added benefit of using line
bred males. We have increased the likelihood of superior offspring by
selecting females from diverse herds in Peru that have exercised selection
pressure and culling techniques for many, many generations. The Northwest
Alpacas breeding flock is 80% Peruvian and 20% Chilean. The females
originate from Accoyo, Rural Allianza at Macusani, Numoa, and Huarapina.
We have also collected choice females from Cohcatanqa and Sollocota
in the Puno district of Peru. The stud males are primarily from the
Accoyo plantel herd, with one from Rural Allianza.
We have chosen all our breeding males based on our view of alpaca perfection.
They have low micron counts and high fleece weights. Hemingway, our
Rural Allianza male, is from their plantel herd located in Macusani.
This herd is known all over Peru for its fine fleece. Don Julio Barreda's
Accoyo males have been line bred in families for many generations and
are consistently beautiful. It is by no mistake that Don Julio is called
the world's finest alpaca breeder. His males are proven and renown throughout
Peru for their pre-potent genes.
The NWA breeding system allows the Accoyo males to add significant hybrid
vigor to the unrelated, but phenotypically similar, females. We will
use our Allianza male, Hemingway, to genetically outcross the Accoyo
bloodline. Eventually, we will have developed our own distinct bloodline.
Every livestock producer aims to improve the quality of their stock.
Historically, breeders chose animals phenotypically, or in other words,
based on their physical appearance. More recently, genetic selection
theory has been developed that allows breeders to make more informed
decisions, which accelerates the improvement of their stock. Genetic
theory is founded in math -- formulas, probability, and prediction.
Bloodstock pedigrees are very important.
American alpaca breeders have an additional resource in the form of
pedigrees from the Alpaca Registry. The Registry registers alpacas only
after their bloodlines have been scientifically verified by the U.C.
Davis Serology Laboratory. These pedigrees can be used to eliminate
uncertainty when making breeding and selection decisions.
GENETIC GAIN
Genetic gain is defined as the increase in average levels of herd production
from one year to the next due to the selection of superior animals for
breeding. For alpaca breeders, production is influenced by a number
of economically important characters. In addition to type or appearance,
these include fleece weight, fiber diameter, uniformity, and the absence
of high micron guard hair.
In estimating genetic gain for one or all of these characters it is
assumed that nutritional and management conditions remain constant.
The rate of genetic gain in any production character is governed by
three factors:
- Heritability - the degree to which each characteristic may be inherited
- Selection Differential - the superiority of selected breeding animals for each characteristic
- Generation Interval - the average age of breeding animals
HERITABILITY
The problem with selecting breeding stock solely on the basis of phenotype
is the effect that the environment plays in the visual aspects of a
given animal. An alpaca in Chile may have 20 micron fleece, but is it
the result of genotype or nutrition? Imported alpacas often produce
much higher micron fleece after a few months on American soil and high
protein diets. The environmental variable must be isolated before a
breeder can be sure that the trait they are selecting for is heritable.
Once the environmental effects are accounted for, heritability must
be established. Alpacas have had few breeding trials or genetic studies
completed to determine the heritability of such genetic traits as fleece
weight, fineness, crimp, staple length, or uniformity. Almost all other
fiber bearing animals have established extensive heritability profiles.
Cashmere and mohair goats, together with all breeds of sheep demonstrate
high heritability indexes for such traits as fiber fineness, fleece
weight, staple length, and clean fleece yield. Alpaca fleece characteristics
should also be highly heritable or, as Couchman put it, "The
heritability of total fleece production in almost all domestic fleece
growing animals is around 0.3 or 30%. I would, therefore, expect to
see similarities in alpacas and Llamas."
Thirty percent heritability is considered high and means that breeders
selecting for specific fleece qualities can expect excellent gain. The
amount of gain is greater when selecting for one characteristic. In
other words, selecting just for fleece weight, for instance, will show
more progress than attempting to also lower fiber fineness at the same
time. In fact, some traits are non-complimentary and selecting for fineness
may inhibit a breeders ability to also select for fleece weight.
SELECTION DIFFERENTIAL
Consider the following example where you are selecting to increase fleece
weight. Within a selection of potential alpaca herdsires from the same
herd that have received same nutritional and management conditions,
you might find a normal distribution of variation in fleece.
If you wanted to select the heaviest 5 percent of fleece cutters for
replacement sires, the average fleece weight of these selected herdsires
would be about 25 percent heavier than the average for the whole herd.
This superiority above the average is called selection differential.
The higher the selection differential, the higher the gain on average.
GENERATION INTERVAL
Generation interval is simply the average age of dams and sires in the
breeding herd. For example, if females first produce a cria at two years
and are bred a total of five times, then the average age of dams in
the herd at any one time will be:
2 + 3 + 4 + 5 + 6
----------------------- = 4 years
5
A breeder can make a similar calculation for males.
The two intervals are then averaged to determine the generational interval
for a given herd. The longer the generation interval (that is, the longer
dams and sires are kept), the smaller the genetic gain in production
from one year to the next. This is because the breeding population will
contain proportionally fewer of the younger, more improved breeders.
There is no doubt that breeders can benefit by studying genetics. The
bottom line is that careful breeding will produce superior results.
For genetic gains to be fully understood and used to achieve further
progress, the breeder needs to measure his success in objective fashion.
Fleece histograms, the recording of fleece weights, measuring staple
length, and tracking animal body weights are all important measures
of a successful program.
COLOR
Color is another very important element of fleece and animal value.
Peruvian breeders select almost exclusively for white, Chilean animals
are not as highly selected, but come in many colors. Color is one way
American breeders can compete in the fleece market. There is often a
market premium paid for natural colors in short supply and high fashion
demand.
At Northwest Alpacas, our goal is to breed primarily for four colors:
black, white, light fawn, and dark fawn. We are aiming to produce uniform
color over the entire animal. We are not breeding for pintos, grays,
roans, or fancy alpacas. This goal is not meant to demean other colors,
but is our method of reducing color variables in our breeding program.
Alpacas which have been selected for color over time by mating white
to white, fawn to fawn, will have a higher likelihood of throwing true
to color cria.
MEASURING SUCCESS
At Northwest Alpacas, we have achieved a uniform group of Alpacas
free of leg faults and bad bites. All of our alpacas are conformationally
correct and exhibit strong alpaca type. In past years, when the conformation
of the domestic herd was generally defective, we worked very hard to
eliminate flaws in conformation. Today, our primary focus is fleece
quality.
Fleece production can be objectively measured. Fleece testing is becoming
wide spread, where only a few years ago no one fleece tested their alpacas.
Fleece histograms are used to illustrate four major elements of fleece
quality.
Micron Count - The average diameter of 66% of a sample, which includes
2,000 measured fibers, is reported as micron count. In alpacas, average
micron count can range from 15 to 45 microns. For an adult Alpaca, 25
microns or less is desirable. (Source: The Average Micron of Grade Superfine,
Bolivian and Peruvian Alpaca Manufacturers.)
Standard Deviation (SD), the first measure of uniformity,
is calculated by determining the range of fiber diameters making up
the average. A fleece sample with an average micron count of 20 and
a SD of 5 microns would be composed of fibers varying by 10 microns.
In other words, half the sample would average 5 microns below 20 and
half would average 5 microns above 20. Acceptable standard deviations
are dependent on the micron count of the fleece being tested. For instance,
fleece with a micron count of 17 should have a maximum SD of 4.25, while
25 micron fleece should have a maximum SD of 6.25. (Source: Cameron
Holt, Melbourne Institute of Textiles)
Coefficient of Variation (CV) is the second measure of uniformity and
is expressed as a percentage. The above example of a 20 micron average
and a SD of 5 would have a CV of 25% (SD divided by micron count equals
CV). CV allows for the comparison of uniformity among animals with differing
micron counts. A CV of 25% or less is desirable. (Source: Cameron Holt,
Melbourne Institute of Textiles) Percent of Fleece Over 30 Microns -
This expresses the percentage of coarse fleece in the sample. Five percent
or less is desirable. (Source: Angus McColl, Yokum-McColl Testing Laboratories)
You may want to consider using the following formula when evaluating
animals from your herd for fleece quality and production value. The
lower the micron count and the higher the fleece weight, the higher
the relative score and the better the animal. The formula's primary
value is for comparing one animal to another on a relative base.
Fleece Weight
---------------------- = Individual alpaca Rating Factor
MC-(CV-25:5)
Fleece weight or density is maybe the most important
quality contributing to the value of an individual animal's fleece production.
Rural Allianza in Peru culls their females if they do not produce 5.5
pounds of fleece annually. Don Jullio Barreda looks for 8 pounds on
females and over 10 pounds on males.
I accounted for uniformity in this equation by using Cameron Holt's
formula for "spinability" as expressed on the histograms produced
by the Melbourne Institute of Textiles. A more uniform fleece is said
to have better "spinability." A fleece with a coefficient
of variation that is 5% less than a fleece of comparable micron count
will spin a yarn that performs and feels as if the fleece was one micron
finer.
ALPACA TYPE
Alpaca type is a more subjective measure of value, but holds great importance
in the show ring and has significant influence on buyer preference.
At Northwest Alpacas, where we specialize in Huacayas, we pay particular
attention to the shape of an alpaca's head, the strength of its wool
cap, and the fiber coverage on its face. All of these features are indicative
of the animal's breeding and fiber coverage over the body. I also look
for an animal which will fit into a square, not too long in the body
nor too tall. All of this contributes to a pleasing look for the animal.
Don Julio Barreda designed his Accoyo ranch logo based on his vision
of the ideal Huacaya alpaca. It is very hard to argue with the components
of type illustrated by Don Julio. Perfect harmony.
Each breeder needs to make their own decision about the goals for their
breeding program. Most livestock industries award quality. The best
animals bring extraordinary prices. Quality and constant improvement
are the best hedge in ensuring a prosperous future.
Mike Safley – Breeder, Show Judge, Author
Article reprinted with permission of Mike Safley, www.alpacas.com