Surface Scanning Electron Microscopy of Suri Alpaca Fiber and Other Members of the Camel Family
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SCIENCE
Surface Scanning Electron Microscopy
of Suri Alpaca Fiber and Other Members
of the Camel Family
By Andy and Dr. Cheryl Tillman
SEM scanning demonstrates that the To provide a baseline to other members
cuticular cell length, height, and scale of the Camel Family, 19 llama, eight
edge angle of suri alpaca fiber is huacaya, six vicuña, five guanaco, and
measurably different from huacaya two de-haired Bactrian camel samples
alpaca, cashmere, wool, and other were also analyzed. Other specialty
members of the Camel Family. fibers analyzed included one sample
The Washington State Disease Diag- each of white angora rabbit, washed
nostic Lab (WADDL) in Pullman, WA fawn mohair, and Bombay silk. Two
analyzed 35 suri alpaca fiber samples samples each of Soft Rolling Skin®
with surface scanning electron micro- (SRS) merino wool, and both domestic
scopy in February through November (in the grease) and very fine, washed
2005 for the authors. The WADDL white Chinese cashmere were tested.
normally uses the Electron Microscopy SEM scanning demonstrates that the
and Imaging Center (EMIC) to cuticular cell scale length, frequency,
identify virus and bacteria species for height, and scale edge angle of suri
the state of Washington. Samples were alpaca fiber is measurably different
Suri fiber is characterized by an indistinct scale prepared by EM Supervisor Chris from these other specialty fibers and
edge that is difficult to visualize even with Davitt, Ph.D., who took two micro- other members of the Camel Family.
digital imaging tools. graphs of each fiber sample. Cuticular scale length is expressed as
the Mean Scale Frequency (MSF) per
Terminology 100 micron (µ) field of view as meas-
ured by the SEM. High-luster suri
appears to be most similar to cashmere,
Angstrom (Å): A unit of length, equal to one ten-millionth of a millimeter,
though it has an even longer and lower
primarily used to express electromagnetic wavelengths.
Compound Microscope: An optical microscope with two ocular lenses. scale height. This study has important
Cuticular Cell Scale: The external-most structure of hair. implications for the alpaca industry,
Highly Evolved: a merino or huacaya that has a high frequency of crimp, or including AOBA and the AFCNA. Suri
a suri with unusually high luster or tightly-penciled locks. alpaca breeders can now claim to pro-
Mean Scale Frequency (MSF): The number of cuticle scales per 100 micron duce a natural fiber which has luster
that are the mean of the data set. that is equal to or greater than cashmere.
Micrograph: A digital photograph of the SEM sample. Due to its very low cuticular scale
Micron: 1/1,000,000 of a meter (1/10,000 of a millimeter, or about 1/25,000th of height, both suri and huacaya breeders
an inch).
can explain why their products have
Scanning Electron Microscopy (SEM): Use of the electron microscope to
view the surface characteristics of an object.
superior handle, compared to wool of
South American Camelid (SAC): A literal translation of Camelidos Sud Amer- similar average fiber diameter (AFD).
icanos, incorporating all the members of the Lama genus, including the
alpaca, llama, guanaco, and vicuña. Sample Demographics
Transmission Electron Microscopy (TEM): Use of the electron microscope Samples were collected from 35 suri
to view an object on-end, rather than on the surface of the subject. alpacas, comprised of 20 male and
15 females. Thirty of the suris were
158 ■ Alpacas Magazine
Most of the straighter fiber samples had excep-
tional luster and a low MSF.
The narrow flat lock was highly correlated to
luster in this study.
offspring from the 1991, 1996, and “Yocum-McColl” sample site used for
1998 Bolivian importations to the laser scanning. The second phase of
USA. These animals were randomly fiber samples had a slightly lower MSF
selected from our own herd based on than the first. Twenty of the suri
whether we had fiber samples or fleeces alpacas had a uniform age range of 11
saved from the previous year’s clip. to 13 months at the time of sampling.
Three Australian suris were also tested. Eight samples from Phase 2 were sec-
These were first-generation suris from a ond or third fleeces, rather than virgin
suri x huacaya cross that were pheno- fleeces (and these animals were three to
typically suri. Two more of our suris five years old). Three of these could be
were from Peruvian origins. Fiber sam- compared to the same animal’s virgin
ples were collected in two phases. The fleece. MSF was within +/- 10% of the
first phase of 14 samples was collected virgin fleece. No significant difference
from shorn virgin fleeces. The remain- was noted between the first and subse-
ing (majority) of samples were taken quent fleeces. The remaining seven A well-locked suri in his second fleece, like
from unshorn suris using a uniform animals were 21 to 25 months old. this animal, typically had an MSF of 7-7.5.
Spring 2006 ■ 159
According to ARI statistics, over half of measure the length of each scale on a
all suri alpacas in the United States are fiber, the height of scale, frequency of
colors other than white. About two-thirds scale, angle of scale, and fiber diameter.
of this study were colored: eleven subjects For the purposes of this article, the rel-
were white, eight brown, seven black, atively simple International Wool Tex-
five fawns, three greys, and one beige. tile Organization (IWTO) DTM-XX-97
The majority of samples (21) had a methodology was used with the excep-
twisted style of lock, including several tion of viewing the samples at 1,000 X
with a highly-evolved “pearl” lock of magnification rather than 600 X. The
3-4 very small inter-twined locks. The higher magnification was necessary for
style of lock ranged from cotted to accurately measuring suri scale height,
“independent.” The remaining samples which is almost impossible to measure
had either a narrow flat lock (3), a rela- even with digital imaging tools. Wool
tively straight fleece that clung closely has a scale height of
Image-J was much more stable on our Commercialization of SEM?
Windows XP platform than the A used SEM costs USD$50,000. Add-
Macintosh-based Scion Image, which is ing the other peripherals can raise the
an industry standard in SEM labs. price to USD $250,000. Training to
Surface SEM of suri alpacas was first prepare the samples and take micro-
conducted in the United States in 1998 graphs would take at least a term of
at the University of Idaho at Moscow, college-level classes in statistics and
by Suvia Judd and Deborah Berman.2 imaging software. SEM is a powerful
Judd and Berman analyzed two fiber tool that can help breeders determine
samples and hypothesized a high corre- the inherent luster of their most valuable
lation between scale length and luster. animals. But it is unlikely that SEM
SEM of South American Camelid (SAC) will ever be as common a test procedure
fiber has been published at least three as laser scanning for determining AFD.
times prior to Judd and Berman in 1988 The cost of the equipment is just too
(Phan), 1996 (Antonini et al), and 1997 great. Cuticular scales can be visualized
(IWTO). Antonini’s study is particularly by an inexpensive optical microscope
important. Extracting the data on just by coating the fiber samples with a lac- A bright fleece like this has a fan-shaped rather
Peruvian suris from that of Argentine quer that enhances the contrast of the than a twisted lock.
SAC with “Lustre” established that scales. While sample preparation may
Peruvian suris have a MSF of 7.5. This be as time-consuming as SEM, this is a
is equal to cashmere. The 1997 IWTO much less expensive method of docu-
study of specialty fibers is one of many menting MSF. Unfortunately, the lac-
which have tried to find an economical quer greatly exaggerates the cuticular
method of testing large quantities of scale height of the sample. Since SAC
cashmere for purity. The very low MSF fiber has a very low scale height, SEM
of cashmere, compared to wool, makes is still the preferred method of analyz-
SEM an effective tool to identify ing surface scale structure.
blended shipments of cashmere.
The author’s sample of suri and Luster
specialty fibers is the largest domestic Luster is the primary, and probably
analysis conducted to date. the only, reason the textile industry
purchases suri alpaca fiber.
Sample Preparation Suri can be used in many of the same
Dr. Davitt prepared the fiber sample by applications as silk and cashmere. It is
cutting the center 13mm (½ inch) out frequently blended with merino, silk,
Luster is the primary reason the textile industry
of the locks. Dr. Davitt believed using or cashmere to add luster to the fabric
purchases suri fiber. This brushed suri coat by
the center of each sample was prefer- used in men’s suits. Beatriz Canedo Patiño is made from 100% suri.
able to one close to the skin or near the “Luster is strongly associated with mo-
tip, and I concurred. The fiber sample hair, based on its relatively large sur-
is mounted on an aluminum disc with face cuticle scales and low cuticle scale
electrically-conductive tape and edge height relative to merino wool.” 3
screwed into place on the sample
dish. A SEM dish holds twelve The end-use of suri alpaca fiber is sub-
13mm sample discs. stantially different than Baby Huacaya,
The fiber samples were placed in which can compete for fineness with
a vacuum chamber and coated with some grades of merino wool. Suri is
20-30 angstroms of pure gold. A high more likely to be used in a semi-
voltage is applied in a vacuum chamber worsted or woolen manufacturing
to a bar of 99.9% pure gold, which process and huacaya in a worsted yarn
coats the fiber samples with a plasma like merino. Our study of eight hua-
of gold ions. The SEM is actually caya alpaca samples demonstrated that
visualizing the gold ions that coat the huacaya breeders can selectively breed
sample, not the fiber sample itself. for enhanced brightness in their fleece.
Platinum and aluminum can also A reduction in MSF of 25-30% should
be used to coat the samples. be relatively easy to accomplish.
Spring 2006 ■ 161
Lock emphasis on an “independent lock,”
It would be premature to assign value than any other characteristic, including
to one lock type over another until a luster or conformation. Our SEM
more thorough SEM is made of suri study did not identify any correlation
alpaca fiber. between a twisted lock and luster. If
The authors had hoped to identify anything, they may be inversely pro-
some correlation between lock types, portional. In this study, the relatively
which naturally occur in the suri alpaca, straight fleeces, and those with a nar-
and the length of scale which is highly row straight lock usually had a longer
correlated to luster. Our sample size and lower scale height than animals
was too small to conclusively identify a with twisted locks. Suri breeders, the
trend. However, it is probably accurate AOBA Show Committee, and the
to say that a straighter fleece is more Judges Training Committee should
likely to have a very low MSF than a keep abreast of SEM technology as it
twisted lock. A literature search suggests applies to suri alpaca fleeces. It would
that some lock types may actually inhib- certainly be premature to favor one
MSF 4.6. Second and third fleeces had a very it perceived luster more than others. lock type over another until the results
low MSF. Pictured is a 3 month re-growth on For instance, a high frequency of of TSN 100-fleece study is completed.
"Rewinds" third fleece. There is no reason not
to show shorn suri’s in AOBA halter classes!
crimp in cashmere does adversely affect
the perceived luster of the fiber. Scale Height
“Perceived luster of wool is affected by The scale height of suri alpaca fiber
staple structure and fiber curvature. was almost impossible to measure,
Low curvature in wool allows the fibers even with digital imaging tools. It is
to more closely align. As Khan (1996) essentially a mono-filament, like silk.
reported, if the staple crimp form in The height of scale on suri alpaca fiber
wool was ‘planar’ (sinusoidal as was almost impossible to measure, even
opposed to helical), such wool would with digital Image-J software. This char-
have a high luster. On this basis, the acteristic is probably as significant to the
use of perceived luster as an aid in the textile industry as suri’s very low MSF.
classifying of cashmere may be con- The scale height of both suri and hua-
Twenty-one of the 35 suri samples were from founded by different cashmere fiber caya fiber has not been accurately report-
well locked individuals like this. A twisted lock curvature. Thus luster of cashmere ed in previous scientific literature, which
probably does reduce luster compared to a should be assessed on manually is probably due to the fact that an opti-
straighter fleece.
straightened fiber to minimize any cal rather than SEM has been used.
effect of fiber crimp.” 4 “The smoothness of alpaca and mohair
compared to wool is due to the scales
Applying McGregor’s findings to suri being around half the height of wool at
alpacas may suggest that a tightly twist- around the same micron.” 10
ed (helical) lock may diffuse light more
than a straighter fleece. It may also While Mr. Sporle made an important
make the handle feel coarser than it and accurate observation about the
actually is. Analysis of the Baby Camel handle of alpaca and mohair, scale
supports the notion that crimp and/or height is much lower than “one-half
a twisted lock may reduce luster in the height of wool.” In our study, it
SAC fiber. was one-tenth the height! Huacaya
“Wool with larger fiber crimp ampli- fiber had slightly taller scale height
tude is associated with softer handle. than suri, but was still typically under
Wools exhibiting a coiled (helical) 3/10µ. The most highly evolved Soft
crimp configuration receive harsher Rolling Skin (SRS) merino fiber like
handle scores than wools with sinu- that analyzed in this study had a scale
soidal (wavy) crimp configurations.” 3 height of 3-4 micron, and most merino
is
Compare the lack of scale height of this suri The low scale height of suri can clearly be seen The scale edge of suri is so indistinct that it
sample to that of merino or cashmere (see in this micrograph which shows three damaged was difficult to measure even with digital
photos on p. 168-169). cuticle scales. Notice how thin they are! imaging tools.
“The greater the directional friction appeared to be elliptical. One vicuna
effect due to the wool fiber cuticle had distinct grooves. Since there were
scales, the harsher the handle.” 3 frequently two fibers in each micro-
graph, and occasionally three, we ana-
This opinion is further enhanced by lyzed nearly 200 suri and huacaya
J.E. Watts and Janie Hicks: fibers for roundness. The elliptical sam-
“Fine cylindrical fibers have low scale ples tended to come from suris that
height. When these fibers are also long, were well locked, but not exclusively
the fiber scales will be long as well as so. More research will be needed to
flat. The combination of long flat scales determine what, if anything, this differ-
imparts a smooth or silky feel to the ence in fiber profile means. TEM
wool.” 5 and/or skin biopsies would be a more
accurate way to determine if a hair fol-
Because wool has such a high scale licle is round or elliptical.
height compared to suri, whether an To an end-user, the very low scale
individual fiber is round or elliptical is height of suri is probably of much
Elliptical Suri Fiber – MSF 5.25. About 30% of
probably not as important to alpaca more significance than if an individual
the alpaca samples had one or two grooves
breeders as it is to merino producers. fiber is round or elliptical. You can running along the surface of the fiber, indicating
appreciate this for yourself by feeling they are probably elliptical rather than round.
Round or Ellipical Fibers? the “hand” of a neck scarf made from
While Watts’ and Hicks’ SRS system is pashmina (cashmere) or merino wool
not universally accepted, their research of similar AFD.
strongly suggests a correlation between
handle and a round rather than ellipti- Transmission Electron
cal fiber. When I showed these SEM Microscopy (TEM)
micrographs to Ian Watt, he soon TEM can also be used to visualize the
found fibers that he believed were ellip- cortex of a fiber sample. The percent-
tical rather than round. These are easily age of orthocortical and paracortical
identified by two thin grooves running cells in the cortex is important. Wool is
parallel to the direction of the fiber bilateral, with both orthocortical and
with a rounded segment between them. paracortical cells, which is responsible
About a third of suri and huacaya for its crimp.9 Cashmere with more
samples had one or two grooves run- mesocortical cells, has a higher
ning the entire length of the fiber. microfibril packing density than wool
Most were completely round. No of the same diameter, so it has less
llama, guanaco or camel samples curvature. Optical analysis of suri fiber
Spring 2006 ■ 163
suggests it is not bilateral, and this
would help explain why it is such a
straight fiber. It is much more time
consuming to prepare samples for TEM
than SEM, and therefore more expen-
sive. TEM will probably require indus-
try support from ARF, AOBA or TSN.
Statistical Analysis
“7.0 Scale/100 micron seems to be a
distinctive parameter for suri.” 6
Dr. Davitt supplied the author with
1.7 megabyte, 8 bit gray scale, TIFF
files captured with a Scion Grabber
card from the SEM. Two micrographs
were taken of each sample. One to
MSF 5.O Suri is nearly as bright as mohair but MSF 5.75. Suri breeders need to reduce the AFD three fibers could be measured in each
has a much lower AFD. of their clip to be competitive with other specialty micrograph. These black and white
fibers. This sample is both fine (
Suri alpacas do have guard hair. Here we see a The number of scales per 100µ varied depend- Bright Huacaya – MSF 11. Huacaya fiber had a
24µ secondary fiber in front of a 40µ guard hair. ing on where you counted them. Suri guard hair higher MSF than suri and a 70 degree rather
had a MSF of 8.65 with a range of 4-13. than 45 degree scale edge angle.
■ MSF 5.5 2nd & 3rd fleece to identify. There was a significant dif-
■ MSF 5.8 virgin fleece ference between the MSF of guard hair
■ Range 3-10.25 on suris between Phase 1 & 2. This
■ MSF guard hair 8.65 was probably due to the uniform col-
■ Range 4-12 lection site used in Phase 2 and the fact
■ Phase 1 & 2 combined MSF 6.15 we intentionally included some samples
■ Substantially lower than Antonini’s that were “hairy” or had a stronger
Peruvian data (7.5). AFD in Phase 1. It is probably accurate
to say that SAC typically have guard
MSF should not be disassociated hair with about 16 scales/100µ.
with scale height. When the scale
height is impossible to measure, and Huacaya
you have to zoom in on the micro- Eight huacayas were evaluated, five
graph to 200% actual size to even visu- males and three females. Samples were
alize a scale edge, you have what is collected from virgin fleece. These were
essentially a mono-filament like silk. highly-evolved huacayas, with 2.0 to
Fine Huacaya – MSF 11.0. Huacaya samples
Several of the suris with a relatively 3.0 crimp per cm, clearly defined
were very fine, seldom exceeding 19µ.
high MSF of 7-8 were so smooth that bundling, and two were unusually
it still had a very slick, cool handle. bright. AFD was 16-19 micron. While
our suri samples were randomly select-
Guard Hair ed, based on fleeces or Yocum-McColl
Primary hair follicles (guard hair) of samples we had on hand, these hua-
the Camel Family had a distinctly dif- cayas were hand-picked to represent a
ferent scale pattern than the secondary dense, bundled, extremely fine, or very
fibers. With the exception of vicuñas, bright fleece. Huacaya samples had an
they were usually much stronger (high- MSF of 11.0, which is similar to wool,
er AFD) and had an extremely high with a range of 8.0-12.0 MSF. This
frequency of scale. These primary fibers correlates to an average scale length of
had extremely low scale height, and 9.0µ. Scale height was greater than suri,
despite their AFD and scale frequency but typically
ples, the longest scale length also had to a single-coat fleece of this quality.
the greatest amplitude of crimp. This These llamas had a scale height less
was a bright, well-bundled, “elite” than or equal to huacaya alpacas.
fleece. Primary and secondary fibers Handle could be either warm or cool.
were nearly the same AFD, though the The suri-llama samples had an MSF
primary fibers could always be identi- of 7.0, which is slightly superior to
fied by their high frequency, and Antonini’s Peruvian suri alpacas. Six of
“sheepy” scale pattern. the 11 donors were top ten World
Futurity suri-llama champions. Alpaca
breeders should take note of how
quickly llama breeders have been able
to improve fiber characteristics.
Huacaya breeders should be able to add
brightness to their fleeces relatively
quickly using SEM, and suri breeders
Guard hair from a short-wool, double-coat llama should be able to simultaneously
had a MSF of 16.5 with a range of 14-19. This reduce AFD while increasing luster.
sample is 50 micron AFD, which is not unusual.
Llama Baby Camel
There are three distinct breed-types of The two Baby Camel samples (Bactrian
llama raised in the United States. We camel) were imported from China.
tested examples of each, including: a They had been de-haired to less than
traditional short-wooled, double-coated 2% coarse fibers (>30µ). The Baby
ccarra llama (32µ AFD and >50% Camel was very fine,
■ De-haired baby camel finer secondary fibers. It would be
■ Low MSF (6.875) interesting to analyze de-haired
■ Higher scale height than suri guanaco roving.
■ Crimp reduces luster & handle
■ Brighter if straightened
Suri breeders should be proud of the
fact that a random sampling of Bolivian
suri alpacas equals or exceeds the MSF
of washed and de-haired Baby Camel.
Baby Camel – MSF 6.875. Crimp greatly reduced
the luster of this de-haired roving. Straightening
the fibers showed its inherent luster.
Guanaco
Dr. William Franklin, one of the Vicuña
world’s leading authorities on guanacos We analyzed three wild and three
and vicuñas, supplied wild-caught gua- domestic vicuñas. Dr. Franklin sup-
naco samples from the Falkland plied the vicuña samples from the
(Malvinas) Islands. Four of the samples Pampa Galeras National Vicuña
came from the back near the top line, Reserve in Peru, and Dr. Toni Cotton
and one from two males who were bit- the domestic vicuñas from Jack and
ing each others’ necks. Four were red- Miriam Donaldson’s farm in Findlay,
dish-brown to fawn in color and one Ohio. The wild vicuñas were two
sample was white, probably coming adults and one cria. Samples were col-
from high on the side. This was truly a lected from center/middle back, top
random sampling! center neck, and center of back with
■ 5 samples from the Falkland Islands guard hair intact. The domestic sam-
■ MSF 11.0 ples were from adult males, and had Guanaco fiber was characterized by 60 micron
guard hair and very fine undercoat. The guard
■ 10-60 micron AFD been de-haired by hand. Staple length
hair is in front of the 10-12µ undercoat .
■ Lower MSF than vicuña was 40-50mm. The providence of cap-
■ Distinct guard hair with undercoat tive vicuñas is not as likely to be as
pure as wild vicuñas, especially in
Based on the similarity of their inci- European zoos where South American
sors, the guanaco is probably closely exhibits will frequently house all the
related to the llama, whereas the vicuña members of the SAC together.
is closely related to the alpaca. The However, these samples had largely
MSF of these authentically-pure guana- similar MSF and AFD.
cos certainly supports a close relation- ■ 6 samples (3 wild-caught)
ship between the guanaco and the dou- ■ Range 8.5-15 scales/100 microns
ble-coat ccarra-type llama. The under- ■ MSF 12.1875
coat of the guanaco samples was very ■ 12-15µ AFD
fine, and some fibers were as small as ■ Very uniform
10 microns! However, the guard hair
was much more prevalent than any of The vicuña samples were among the
the other breeds or species of SAC, and most interesting of the study. They
several 60-micron guard hairs would had a higher MSF than either hua-
Vicuña – MSF 12.875. The vicuña samples had a
dominate nearly every micrograph, cayas or llamas, and the difference higher MSF than llama, guanaco or huacaya.
making it difficult to isolate the much- between primary and secondary fibers AFD 12-15µ.
Spring 2006 ■ 167was difficult or even impossible to MSF is intermediate between a huacaya
determine by SEM. This may be one and suri, which may or may not be due
reason the MSF was higher, since with to their huacaya ancestry. (The suri
all other members of the SAC, it was with lowest MSF had the greatest per-
possible to count primary and second- centage of huacaya pedigree). The scale
ary fibers separately. This will be edge and height on 2 of the samples
amusing to those of you who have was more distinct than most suris, par-
ever de-haired a vicuña fleece. (Those ticularly one of the blacks.
little red guard hairs are easy to see but
hard to pluck out!) The MSF and Paco-Vicuña
AFD of the vicuña samples were the A paco-vicuña is the offspring of an
most uniform of all SAC tested. This alpaca and a vicuña. A single paco-
is a significant observation, consider- vicuña sample was evaluated from the
ing the random nature of the wild- herd of Phil and Chris Switzer in Estes
caught samples. A follow-on analysis Park, Colorado. Five fibers were ana-
Suri x Huacaya Cross – Average MSF 8.4. Three of vicuña fiber with SEM should lyzed in two micrographs. The provi-
F1 or BC1 suri x huacaya crosses from Australia probably analyze guard hair separately dence of this animal could not be veri-
were analyzed. from the under-coat. fied, but this breeding male had many
vicuña-like characteristics, including
HYBRIDS: body size, weight, bi-coloration, staple
First-Generation Suri x length, and personality. It was an in-
Huacaya Cross utero offspring out of an imported
Kenneth Madl of Aviana Farms, sup- Chilean huacaya.
plied three colored suris from his herd ■ One sample
which is agisted in Strathbogie, ■ Range 11-17 scales/100 microns
Victoria, Australia. Two were black and ■ 13.6 MSF
one silver-grey, 11 months old. Two ■ 13-24 micron AFD
were F1 suri’s with 2-3 generations of ■ Higher MSF than huacaya or vicuña
suri x huacaya crosses in their pedigree,
and one was a Back Cross 1 with two This animal had the highest MSF of
generations s x h and one s x s. Two of the series, which probably goes a long
these went on to win their classes at the way toward proving its vicuña pedigree.
2005 Australian national alpaca show. The uniformity of AFD was not nearly
Over 3,200 suri alpacas were imported as pronounced as a pure vicuña.
Paco-Vicuña – MSF 13.6. Paco-vicuñas had the into the United States from Peru,
highest MSF in the study, and a much greater
Bolivia, and Chile between 1991-98. OTHER SPECIALTY FIBERS:
range of AFD than the pure-bred vicuñas.
With such a large population to start Soft Rolling Skin (SRS) Merino
with, the vast majority of American As anyone who has ever shopped for an
breeders do not cross huacaya and suri expensive man’s suit can tell you, ultra-
alpacas. Many fewer suris were import- fine merino wool should probably be
ed into Australia, and as a result it is a classified as a “specialty” fiber. Even an
commonly-accepted practice in that untrained hand can distinguish the dif-
country to cover a huacaya female with ference between a 16µ wool and more
a suri male. common fabric. When merino is
■ Three samples from Australia blended with cashmere or suri, the
■ Two true black, one silver-gray handle improves even more. The two
■ Range 6.25-11 scales/100µ SRS merino samples we tested had a
■ 8.4 MSF (intermediate between MSF of 8.6, which is exceptional for
huacaya & suri) wool. These two- and three-year-old
merino rams had a scale height of just
As the photos indicate, these alpacas 3-4 microns, half that of most sheep
are phenotypically suri and would not breeds. However, the abrupt scale edge
SRS Merino – MSF 8.6. While half the scale
be out of place in most colored suri was easily measured. These were
height of other sheep breeds, SRS merino is
still more than ten times greater than huacaya alpaca herds in the United States. remarkably well-bundled fleeces, with
or suri alpaca. While it is a small sample size, the each lock measuring less than ½ cm
168 ■ Alpacas Magazinewith SEM, the alpaca industry should
be able to substitute suri fiber for many
applications that currently use cash-
mere or mohair.
SRS Merino Fleece
Mohair Fleece
with 6-7 crimps per cm. (This is two White Chinese cashmere, MSF 8.625, 14.2µ AFD.
to three times the curvature of a typical Mohair
huacaya). The two samples were pro- We evaluated a single sample of
vided by Ian Watt of Moro Bay, imported fawn mohair. Most mohair
California. production comes from South Africa.
Mohair is brighter than cashmere, and
Cashmere subjectively, appears to be as bright as
SEM has demonstrated that suri fiber suri. This sample had been washed.
is most similar to cashmere and Even though mohair is very coarse
mohair. These goat fleeces must be de- (typically■ Single coat fleece from the silk worm’s cocoon, and again
■ 11-15 micron AFD after it is wound. It was very bright.
■ Spiral scale pattern Even at 1,000 X, it was not possible to
■ Range 10-12 scale/100 microns see where the filaments had been reeled
■ 10.6 MSF together. It appears that silk is the only
natural fiber which has a smoother
Angora is so fine and without guard surface structure than suri.
hair that we could easily measure three
fibers per micrograph. The deep Challenges and
grooves between the spiral-shaped Recommendations
scales probably reduce the handle of SEM of suri fiber is a fortuitous con-
Angora in the same way that an abrupt vergence of research and marketing.
scale edge effects wool. The scale edge Suri alpacas have a lower MSF and
angle is similar or greater than huacaya. much lower scale height than cashmere,
but no one knows it! To secure their
Bombay Silk – AFD 10-12µ. Silk does not have Bombay Silk place as the natural fiber with the
a cuticle scale since it is reeled together from Imported Bombay silk had an AFD of greatest combination of fineness and
4-20 filament ends from the silk worm. 10-12 micron. “Bombay” silk comes luster, AOBA judging standards need
from the mulberry leaf eating silk to prize luster as highly as an independ-
worm. One-hundred-ten-thousand ent lock structure. And we believe this
tons of silk are sold each year, making needs to occur in the show ring, not
it the dominant luxury fabric in the just on the score card for a fleece com-
world. Since it is not a mammal, silk petition. Additionally, we recommend
does not have a cuticle scale structure. that the Alpaca Research Foundation
Silk is reeled together from 4-20 indi- (ARF) help sponsor research on suri
vidual filament ends to make a single fiber. (The Suri Network already is).
monofilament that adheres together Clearly, AOBA and the Alpaca Fiber
due to the gummy texture on the sur- Cooperative of North America
face of the filament. Silk is washed in (AFCNA) both need to make suris’
warm water to separate the filament unique characteristics an integral part
IWTO methodology views fiber samples at 600 X
magnification which allows 5-6 fibers to be Acknowledgements
analyzed at a time. Dr. Davitt increased magnifi-
cation to 1,000 X so suri scales could be visual- The authors would like to thank the following friends and colleagues for their assistance:
ized more easily. ■ Dr. William Franklin, who supplied us with wild-caught guanaco and vicuña samples
from Pampa Galeras and the Falkland Islands.
■ Dr. Toni Cotton of Findlay, Ohio, who provided the domestic vicuña samples.
■ April and Richard Angotti of Benvenuti Farms in Bend, Oregon, who
provided the highly-evolved huacaya samples.
■ Sherry Sheridan of Aloha Farms in Bend, Oregon, who provided the
double-coat llama sample.
■ Susan Tellez for her foreign language literature search of SEM of the SAC.
■ Kenneth Madl, who provided us with many publications on contemporary wool and
cashmere research from Australia, and his first-generation suris from suri x huacaya
crosses.
■ Ian Watt, for help in identifying round versus elliptical fibers, and for providing the
highly-evolved SRS merino samples.
■ Our local wool guild, the Textilians, who provided us with cashmere, silk, and Baby
Camel (Bactrian camel) samples.
■ Angus McColl, who provided the white Chinese cashmere.
■ Dr. Kathleen Cullen of Spokane, Washington, who provided the white Angora.
■ Chris and Phil Switzer of Estes Park, Colorado who supplied the paco-vicuña sample.
MSF was not related to AFD as it appears to be
■ Dr. Chris Davitt, WADDL, who prepared and scanned the fiber samples and tutored
with other specialty fibers. This is good news
since it suggests you can select for enhanced me on the use of imaging software.
luster and reduced AFD simultaneously.
170 ■ Alpacas Magazineof their marketing and advertising cam- ■ The “long smooth scale”™ of suri
paigns. The low scale height of huacaya fiber averages 16.3µ long
fiber compared to wool can also be ■ Huacaya samples averaged 9.0µ
emphasized! To be competitive in the ■ This equates to a MSF of 6.125/
luxury fiber market, suri breeders need 100µ suri and 11.0 MSF/100µ
to reduce the AFD of their clip. huacaya
Fortunately, there was no correlation ■ MSF was not correlated to fiber
between luster and AFD in either this diameter.
or Antonini’s study, and it should be ■ A low MSF was not correlated to a
possible to select for both characteris- twisted lock and may be inversely
tics simultaneously. related
Cheryl and I have been raising alter- ■ Scale height on both huacaya and
native livestock for over thirty years. suri is much less than previously
It would be premature to assign value to one
As a result we usually take a macro reported.
lock type over another until a more thorough
view of the issues which face our study of SEM is made of suri alpaca fiber.
industry. We have learned that if you
do not breed for something, you lose Andy and Dr. Cheryl Tillman funded this
it. Whether this is maternal ability research on suri alpaca fiber. The Tillmans
(milk production), thriftiness, confor- imported the influential colored suri alpacas
mation, or luster, if you take a charac- from Hacienda Acero Marka near La Paz,
teristic for granted, you will lose it. Bolivia in 1996. Andy has raised llamas since
The results of this research are both 1975 and alpacas since 1982. He is a member
exciting and sobering. For instance, of The Suri Network research committee.
there is certainly no reason not to Cheryl Tillman has been a camelid veterinarian
show shorn suris in AOBA halter since 1985. She sits on the board of directors
classes, due to the close correlation for the US Animal Health Association, serves
between a virgin, 2nd, and 3rd fleeces on the AOBA/ARI Government & Industry
MSF. On the other hand, we are Relationship committee, and has reviewed
probably not using some of our best research proposals for Morris Animal
males, those with the greatest luster Foundation for many years. They can be
and lowest MSF. contacted at andy@tillmansranch.com.
Summary A fan-shaped lock and narrow flat lock may be
It would be premature to assign value under-appreciated for luster.
to one lock type over another until a
more thorough SEM study is made of REFERENCES
suri alpaca fiber. Like many scientific 1. College Physics, 4th edition, Franklin Miller Jr., pg. 659
enquiries, this one has raised as many 2. Purely Suri magazine, volume 2, 2004, Suvia Judd and Deborah Berman, pg 18
questions as it has answered. The 3. “Is Merino Wool a Luxury Precious Fiber?,” Bruce McGregor, Australian Farm Journal,
authors have scanned enough fiber July, 2003
samples to determine that suri alpaca 4. “Influence of Nutrition, Fiber Diameter, and Fiber Length on the Fiber Curvature of
fiber is measurably different in scale Cashmere,” B.A. McGregor, The Australian Journal of Agricultural Research, 2003
length, frequency, edge height, and 5. J.E. Watts and Janie Hicks: The Soft Rolling Skin® (SRS)® Breeding System for Alpacas.
edge angle from wool and huacaya 6. “SUPREME-Project: Cuticular Cell Mean Scale Frequency in Different Types of Domestic
fiber. It is probably most similar to South American Camelids (SAC)”; M. Antonini, E. Frank, M. Gonzales, F. Pierdominici,
cashmere and mohair but with an even S. Catalano, M.V.H. Hick, & F. Castrignano; European Symposium on SAC, University
lower scale height. The “take home” di Camerino Press, Matelica (MC) Italy, pp. 142-152 (1996)
lesson from this SEM study is that 7. IWTO DTM-XX-97: “Quantitative Analysis of Blend of Wool with Specialty Fibers by Scanning
what is truly unique about suri alpaca Electron Microscopy,” International Wool Textile Organization (1997)
fiber is its luster. This should be kept 8. “Characterization of Specialty Fibers by Scanning Electron Microscopy”; Phan K.H.,
foremost in mind in any future discus- Wortmann F.J., Wortmann G., and Arns W.; Shriftenz. Dtsch. ; Wollforxchungsinst;
sion of possible breed standards, end- p. 106 (1988)
use, or show standards. 9. Properties and Performance of Goat Fibre, JD Leeder, BA McGregor and RG Steadman (1998)
■ Suri and huacaya fleece can be differ- 10. Elite Natural Fibre, Grower Expectations & Processor Requirements, Peter J. Sporle, 1994
entiated by SEM 11. Alpaca: Large Scale Industrial Perspective on Fiber Processing, Juan Pepper, 2005
Spring 2006 ■ 171You can also read
