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What Makes a Champion
Introduction
I want to talk about “the fleece on the alpaca”, and I should like to start by asking, which are the important characteristics in the fleece ?, and are all characteristics equal from the economical and technical point of view?
According to the present AOBA Rules, judges must pay the same attention to the fiber characteristics as well as to conformation (50% fleece, 50% conformation). However, according to what we know from other alpaca producing countries, the fleece is given higher emphasis – 70% - in case of Perú and – 60% - in case of Australia . The reason? In the case of Perú they have a very old tradition of alpaca breeding and a highly advanced modern textile industry. The finer the fiber, the higher the economical return end product will give. Then for the Peruvian breeders the most important trait is fineness, so most of the effort in genetic improvement has been done by introducing fineness into the alpaca fleece. I believe that fineness should be also highly emphasized in the American Herd of alpaca.
Which are the other important characteristics of the alpaca fleece?, how are they correlated or associated with fineness? I will mention some of them:o Crimp formation
o Staple length
o Density
o Uniformity
o Luster or Brightness Also, there are other important characteristics utilized in the modern textile industrywhich are difficult to measure on the animal, like:o Medullation
o Resistance to Compression ( Newton and Kilotex).
o Washing yield
o Wax and Suint percentage
o Mean staple strength
o Resistance to traction
o Content and type of vegetal material
o Resilience
o Color
o Breakage position, etc.
And I can add many more. Fiber Fineness
The current wool and fiber industry has completely changed its system of assessing fineness from the traditional quality number (counts) to the mean fiber diameter or micron system.
Fineness is the results of the Genetic Make-up of the alpaca, influenced by the Environmental conditions. In sheep the heritability of mean diameter (fineness) is about 0.5 and we can extrapolate this figure to the alpaca fiber heretability. However we must know that there is no fineness heritability studies in alpacas, so, this percentage must be taken with caution.
What does 0.5 of heritability mean? Heritability describes the strength of inheritance of a character, i. e. whether it is likely to be passed on to the next generation or not. According to Prof. C.Dalton, heritability is “For a given trait the amount of the superiority of the parents above their contemporaries which on average is passed on the next offspring”. The notation h 2 is given to heritability and is expressed on a scale from 0 to 10, or 0 to 100% where:
Low or weak heritability : 0 – 0.1 (0-100%)
Medium or intermediate: 0.1 – 0.3 (10-30%)
High or strong: 0.3 or above (30% or more).
This means that in sheep fiber fineness is highly inheritable. And we can assume with caution, that fiber heritability is also highly inheritable in alpacas .
The differences founded in different strains of alpacas coming from different countries and breeders, are very marked as a results of generations of selection for fineness.
Breeders must take into consideration that there is a tendency for fine fleeces to be light in production weight, because the genetic correlation between fleece weight and fineness is negative. In other words, more fine less weight. This sometimes means lower returns to breeders (sometimes fleece buyers, do not pay for fineness, but for weight).
However, many other genetic factors are involved in the expression of the heritability. The number of Primary and Secondary follicles in the skin of the newborn alpaca, have a mayor influence in determining fineness, and the fleeces produced by sheep with high follicle number in the skin tend to be both finer and heavier. However, here is where nutrition plays a very important role. Nutrients, particularly amino-acids are needed for the growth of individual fibers and are supplied to the follicles, through an extensive network of blood vessels and capillaries.
It has been found in sheep, that follicle maturation, i.e. from development to maturation has ceased by the time the lamb is 6 months old and the most effective period of follicle maturation, as shown in the next diagram, is from 80 days after conception to 70 days after birth. Therefore, a high level of nutrition during this period is vital to ensure optimum follicle development. If the pregnant ewes in this critical period do not received a very good nutrition, the growing and maturation of Primary and secondary follicles will be low in spite of the high genetic make-up of the mother for high follicle numbers. As I said before: Fineness is the result of the Genetic make-up of the alpaca, influenced by environmental conditions (Food intake in this case).
Follicular Development time line for alpacas
Effects of Nutrition and Photoperiodicity on Fiber Production.
In sheep, research has shown that there is an important relationship between nutrition and fiber production. It is worth noting that wool grows continuously throughout the life of the sheep. However, the quantity and quality of the fiber produced each year will vary according to seasonal conditions and the nutrition available to the sheep. This concept can be extrapolated and the knowledge applied to the alpaca.
Sheep maintained under natural conditions of feeding and climate, showed a minimum wool growth-rate in winter and a maximum in summer, regardless of temperature changes. Many studies support the evidence that wool growth rate depends mostly on photoperiodicity. Growing differences were more marked in animals under natural feeding (natural pastures).
This is the wool growth rate during the different seasons of the year Is there particular reference to which country this applies to i.e. Peru?):
Winter: 14%
Spring: 20%
Summer: 34%
Autumn: 32%
In Perú the shearing time is during the spring, because the natural environmental conditions improve, especially food availability and temperature.
In USA in spite of the excellent feeding strategies all the year round, shearing should be done also in spring, in order to take advantage of the longer photoperiod of the summer months.
In periods of prolonged drought the fiber produced in the highland of Perú is usually much finer, as alpacas often lack adequate nutrition to enable them to maintain maximum fiber production; and such wool is often termed: “Hungerfine”. If the drought is particularly severe the fiber will become so thin that the tensile strength is reduced significantly.
In the last 10 years, I read some studies done in USA by some American breeders, showing the great increase in fiber diameter of alpacas fed at the quarantine stations of Perú, after being brought from the highland breeders.
These studies show us the changes in the level of nutrition from minimum levels to overfeeding and the effect this has on the fiber diameter, from “hungerfine” fleeces to overfed alpacas fleece. Nevertheless, other important information has been neglected such as range of variation of fineness, the percentage of animals that showed minor changes, the nutritional status of the animals, the quantified level of nutrition in both places (highland and quarantine) the geographical area from where they originate and the season of the year when studies were done (photoperiod). This type of study resultsin erroneous conclusions, creating more confusion and confounding the evidence of the few bonafide scientific reports done elsewhere.
I want to mention one of the most important pieces of scientific work done by Angus Russel, who reached the following conclusions:
“The alpaca fiber production is influenced by nutrition, but the effect is proportionately greater on fiber length that on diameter. This offers opportunities for increasing fleece weight with only a minimal penalty in terms of fiber quality”. Thus he concluded, the relative contributions of length and diameter to the increased fiber weight resulting from the higher level of nutrition are of the order of 80% and 20% respectively.
In the next figure you will see the changes in body weight in adult alpacas, the fetal weight increment and the percentage of natural forage production in the highland of Peru:
Relationship between Crimp and Fiber fineness
Crimp, also called “character”, is the waviness you see along the fiber and the staple. One way to measure crimpness is the number of waves per inch or centimeter. A caliper is used to compare the scale with the natural undulations of the staple.
Crimps per inch show high values on the back (saddle) and neck and are less pronounced on other parts of the body.
The suggested Grades for fine Wool based on Length of Crimp/depth of crimp ratio, are the following:
Good: Very deep crimp, in relation to crimp length, good character, usually high number of crimps per inch (how many?).
Average: Average crimp, depth in relation to crimp length, fair character, usually average number of crimps per inch. (how many?).
Poor: Shallow crimp in relation to crimp length, poor character, usually few crimps per inch. (how many?).
Some researchers working with different breeds of sheep and different strains found that the relationship between fineness and crimp shows some departures from average; in other words, is not strongly correlated with fineness.
However, when dealing with individual breeds and also some strains, the relationship is positive, and one can predict the diameter with a probable error of about two microns.
According to Wickham fineness is not strongly inherited and is controlled by a variety of environmental factors including nutrition and internal and external parasites (that indirectly influence nutrition). A high clover component of the diet has been shown to have a beneficial effect while cooper and zinc deficiencies are very detrimental.
In the Peruvian conditions of alpaca breeding, crimpness is highly appreciated by the breeders. They report that “in 90% of the cases a crimped fiber is a visual indicator of fineness”.
When I visited an alpaca textile factory in Perú, where the fleece sorting is carried out entirely by woman’s hands, the highly crimped fleeces end up in the very fine fleece section.
In a very recent study, 20 fine fleeces were selected by 4 trained people (10 with good crimp and 10 without crimp). Results showed that the crimped fleeces were in the range of 17.5 – 22.0 microns, and in the other non-crimped fleeces, the range were of 18.0 – 27.0 microns (one was 18 microns and the average was 24.0 microns).
What can we extract from this little piece of work? :
(1) Hand fineness evaluation was very good,
(2) Good correlation between fineness and crimp and
(3) the number of fleeces were not enough to have statistical results.
I myself would like to investigate with a large number of Huacaya fleeces, from different age, sex, color and strain, the widespread opinion that crimp is related positively with fineness.
The presence of crimp, is not only a probable indicator of fineness, but also has some other qualities:• Highly appreciated for the hand spinners
• High crimp frequently inhibits the felting that results in cotting
• Hand spinning of crimped fleece, produces a more regular and uniform yarn
• Some textile researchers have found crimp to contribute some desirablequalities that are useful in quality textile production.
• Crimp is related to dense fleeces. High crimp tends to form very dense locks or staples.
• Crimped wool is more circular (transversal section) and therefore less elliptic and has less medullation. All these important characteristics deserve a “must”. They MUST be taken into consideration among the important traits of the alpaca fiber. And also, deserve a carefully study in the field with people trained in performing fleece studies, experimental design and appropriate statistical analysis.
Fiber diameter, age and Length of the Staple
In Perú, between 40 - 50% of the alpacas are shorn annually, and the other 50% are shorn between 1½ and 2 years. It has been shown experimentally, that under fair to good nutritional levels in natural pastures, alpacas can be shorn annually, and the staple length will be superior to the 7 cm requested by the textile industry.
Shearing each year, rather than every two years, the breeder gains about 30-35% more in fleece weight, that means higher economical return.
With an annual regime of shearing, an increase of fiber diameter of around 0.30 microns yearly it is expected, and also that the length of the staple diminish in about 0.36 cm each year.
Also, here is a Table of the staple length (cm) in relation to age and breed.
However, in this study, the number of shearings can not be separated from age. In other words is the shortening of the length of staple due to the aging of the alpaca or the number of shearings it has undergone in its lifetime? Shearing could possibly have an indirect effect through nutrition, since on a constant ration more food might be required to maintain body temperature immediately after shearing and therefore less food might be available for fiber growth.
However studies done in sheep, on free choice rations, the appetite tend to rise after shearing and consequently wool growth may be increased.
Factors that affect Fiber Length
The next most important component to fineness is Fiber/or Staple Length, where the fiber is going to be processed in the mills. The length of wool in the grease is usually expressed in terms of Staple Length, and is the length of each lock from root to the tip of the fiber. The mean fiber length, of the individual fiber tends to be greater than the staple length, and is the total?average length of a group of single fibers after being stretched completely, and you will find that the fiber length of a crimpy lock is longer than the staple length. For breeding purpose staple length is widely used.
In sheep wool, fibers longer than 100-125 mm are highly priced. The same follows for alpaca fiber, however, alpacas under natural pasture conditions (Highland of Perú), produce the following staple length from the first shearing at 10 months of age to more that 8 years:
Huacaya females: from 123 to 89 mm
Huacaya males: from 126 to 104 mm
Suri females: from 160 to 114 mm
Suri Males: from 168 to 117 mm
The growing of the fiber length is governed, as is fineness, by the genes, and also influenced by the environmental factors.
We know that around 30% of the fibers break in the early stages of processing, when the fiber is healthy, sound and untangled, but 60% or more of the fibers may break when they are tender and/or entangled. This breakage is the result of a temporary reduction in the growth rate of the fibers, and is associated with a thinning and shedding of some fibers from the follicle. Thus tenderness and cotting of fiber must be regarded as factors leading to shorter lengths.
There are four main factors that influence unsoundness of fleece:
• Winter reduction in fiber growth.
• Pregnancy: According with studies done in Perú, lactating mothers will produce 5% less fleece weight, and those lactating and gestating, will produce 8% less fleece weight.
• Poor nutrition and
• Parasitism.
Improving winter nutrition is the solution to this problem, as well as good nutrition in the last third of gestation and during the first sixth months of the crias lives. Drenching alpacas is good management practice to avoid the effect of parasites in the quality and growth of the fiber. However it must be remembered that susceptibility to cotting is reasonably heritable and that selection for fleece weight will produce alpacas that are more resistant to both unsoundness and cotting.
Luster and/or Brightness
Wools differ in the quality and quantity of its luster. Luster is defined as the sheen, gloss or shine of the fleece. However, luster is not only a visual observation of sheen, is also incorporates the tactile silky feeling of touching the fleece.
The luster characteristic depends, not only from the outer cells of the fiber (cuticle scale), but from the size and straightness of the fiber. It is not easily perceptible on isolated fibers, but more obvious in the locks where many fibers are clumped together, also in thread, yarns and cloth fabric.
The Peruvian breeders use the term “Brightness”, when some Huacaya fleeces shows a sheen or luster. Luster is an important characteristic in the Suri fleece but is not very common in Huacaya breed. The wool industry describes three types of luster: silvery, silky and vitreous. The silvery luster is found in the finenest Merino wools with high degree of crimp; the silky luster is present in the long staples of British breeds, like Lincoln and Leicester; and the vitreous, in the Mohair and other goat fibers. Von Vergen studies in the alpaca fleece, mention that Suri shows a silky luster and Huacaya has a silvery luster.
Most of the expression of softness of handling correlates to fiber fineness and luster.
Written by Dr Julio Sumar
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