The primary goal of an alpaca breeding program is to efficiently and safely impregnate females with the least amount of stress for all parties involved. The role of the alpaca manager is to
facilitate breedings to maximize a herdís development. Doing this effectively requires some knowledge of reproductive biology, an understanding of basic genetics, and interpretation of
behaviors that indicate reproductive status. Developing the ability to accurately identify aberrant
aspects of reproductive performance also helps improve program efficiency.
This article gives an overview of some of the reproductive techniques used in South America. In
addition, some troubleshooting tips are offered in an effort to provide the North American alpaca
breeder with new insight and practical ways to sleuth and avoid reproductive problems
within their herd.
South American Breeding Practices
Male to female ratio
While many North American breeders micromanage breedings, carefully choosing the right stud
for a chosen female, this is not the typical arrangement elsewhere. In South America, one stud
may reside in a group of females with the hope that heíll impregnate them all.
The best ratio of breeding males to females is discussed in great detail in South American
literature. Karl Koford, the preeminent vicuna researcher of the l950ís, cites a
preferred ratio among the large alpaca operations in Peru of 1 male alpaca for every 10 females.
Alpaca researchers at La Raya during the l970ís cite 1 male to 30 to 40 females for
maximal breeding. In larger herds with multiple males, Julio Barreda, one of Peruís well-known
alpaca breeders, recommends 3 males to 100 females or 8 males to 200 females. Finding the
ideal ratio is elusive because the number of females an average male can breed varies a great deal
depending on his unique capabilities and the conditions in which he lives. The track records of
two studs, operating simultaneously in the same large herd in North America, illustrate this point.
One male successfully impregnated 15 females in a two-year period, while the other impregnated
50. This result may be influenced by potency, dominance, or other variables. In large herds in
which the males commingle, male performance and reproductive focus can be hindered because
domination struggles interfere with breeding.
How often can a male effectively breed?
Males in South American herds have been known to copulate as many as 30 times per day for
lengths of time ranging from 3 to 50 minutes. However, by the end of the week the same males
may only copulate a couple of times daily, or not at all, despite the presence of open females.
Physical exhaustion caused by excessive breeding and the demands of protecting turf and females
from rival males can result in a decreased ability to breed.
Alpaca reproductive expert, Walter Bravo, PhD, has found that males who breed more than 4
times a day may actually be counterproductive. Male potency drops off sharply after 3 breedings
in one day and is rarely effective after 5 breedings in a day. Males that breed too many females in
a short period of time may, in essence, be shooting blanks. If their sperm is depleted, their
amorous activities are likely to stimulate ovulation without achieving conception, resulting in an
unbred female being out of the service pool for 15 to 20 days until her progesterone level declines
sufficiently and receptivity returns. In large South American herds, where males are rotated on a
weekly basis, it is possible for an individual female to be serviced by a succession of males who
have been so active that their potency is depleted, resulting in the female passing through the
South American breeding season (November through January) unbred. This way of breeding may
account for the low fertility rates in some South American herds in which as many as 40% of the
females in a herd will not produce a cria on an annual basis. The saddest irony is that a female that
has been exposed to this kind of "breeding program," but has not become pregnant, may actually
be labeled as infertile and culled due to no biological weakness on her part.
Efficiently managing male breeding potential
The South American literature on herd reproduction primarily discusses managing large alpaca
herds. Behavioral research findings from study of the wild vicunas and guanacos are a valuable
resource, and this information can be extrapolated and used to maximize breeding efficiency and
safely manage alpaca males here in North America.
In South America, a territorial male becomes the sentry guarding a grazing area where he breeds
his herd of females while repelling lesser males whose genes are literally chased and banished
from the gene pool. In free-ranging guanacos and vicunas, only the strong, agile, and
aggressive get to breed. Bachelor herds (groups of males of various ages) patrol the areas around the family
groups (females, crias and one territorial male), always watching for a sign of weakness or
faltering in the territorial male. Within the bachelor groups, the next generationís territorial males
are developing. Though alpacas are somewhat subdued compared to their wild brethren, these
basic instinctual patterns persist in domestic camelids.
It is important for the alpaca manager to realize that amongst the wild camelids (vicunas and
guanacos), the bachelor groups are generally compatible and arenít overly aggressive towards
one another. However, once a bachelor wanders into a territory with females and a territorial male,
individuals within the bachelor
herd may become increasingly aggressive with their herdmates.
In the early years of North American alpaca breeding, males were often run with a group of
females in a manner much like the
South American wild camelids,
with 1 male running amongst a
band of 10 to 15 females.
Typically, males were allowed to
develop an aggressive and
intolerant attitude towards other
males. As a result, the "herd sire"
would occasionally become a
management challenge, requiring
his own pen to minimize fighting.
Males in the permanent company
of females sometimes develop intractable habits of intolerance towards other males. Proximity to females increases this aggression. Just as in nature, when a bachelor group of vicunas moves close
to a territorial male, the individuals in the group begin exhibiting aggressive tendencies. Moving a
tranquil bachelor herd of male alpacas into close proximity of a female group can trigger aggressive behavior as males jockey to control the fence line nearest the females. In a fenced setting, with a breeding male on a common fence with rival males, the interaction between the
breeding male and the other males can be so distracting that the arrangement contributes to a
decrease in mating activities.
Creating an on-ranch bachelor herd has several advantages for the alpaca manager. The greatest
advantage is that male alpacas or llamas can be housed together in fairly large numbers. They
must, however, be out of sight from females. In order to avoid the development of territorial
aggressiveness when allowing a male to breed, the manager discourages the male from
establishing his territory by bringing him to breed on "neutral ground." The male is only allowed to
breed in this neutral zone and is then returned to the bachelor herd when his work is done. With
this technique, the male never establishes "a harem" and therefore never establishes a "harem
mentality." The breeding can be carefully monitored to assess the maleís breeding performance
(willingness to pursue a female, confirmation of penetration and copulation for a desirable length
of time). This method, which is sometimes referred to as "hand breeding," allows the luxury of
absolute certainty as to the quality of contact while limiting a particular male to two breedings a
day, thus assuring the maleís maximum potency with each breeding. This method also allows
breeders to assess the femaleís response to the male, thus monitoring the reproductive status of a
given female. Lastly, the conception date can be precisely recorded. The only prerequisites to
such a program are: the creation of an advantageous fencing scheme that moves males away from
females, the creation of a neutral breeding pen, and the training of males so they can be haltered
and moved easily between their herd setting and the neutral breeding pen.
Identifying and Sleuthing Problems in Reproduction
Fortunately, most alpacas breed readily and do
not have reproductive problems. When
problems do occur, the cause can be simple or
complex. Sometimes practical solutions are
unknown because the alpaca manager is
inexperienced, or they are simply forgotten.
Following are the authorís "Seven
Commandments to Wholesome and Fruitful
Remember it takes two to tango.
Reproductive problems can occur in either sex.
Often the female is suspected of being infertile
when she does not become pregnant. Until the
reason for lack of conception is positively
determined, both the female and male should
be considered as equal suspects.
Make sure the participants are healthy.
As obvious as this suggestion may be, it is often
overlooked because of inexperience or haste to
breed. Animals selected for reproduction
should be in optimum health. Females, stressed
due to the social demands and nutritional needs
of the last cria, are often pressed back into
service before they have had time to recover.
Animals should be body-scored before
breeding commences. Animals who are emaciated or obese are compromised reproductively.
Poor diet (too lean, rich, or imbalanced), parasite loads, and cria demands, all compromise
reproductive capability. Female animals about to become pregnant must be strong and vigorous.
This is especially important in alpacas because they have disproportionately large babies (often
around 20 pounds) as compared to the size of the mother (often around 150 pounds).
Donít blame him; it could be her fault.
If you are certain the male is potent and performing well, youíll need to consider whether the
female is a maiden or proven breeder. Solutions for a failure to conceive differ markedly between
maiden and proven females.
The absence of courtship behavior (normally
showing either receptivity or rejection) in the
maiden female is important and may indicate
several possible problems. Physical or
behavioral immaturity, insufficient hormonal response, or even an incomplete reproductive
tract may be possible causes. A good camelid
veterinarian can help diagnose the particular
causes of problems with a maiden. If courtship
behavior is present in the maiden female but
conception remains elusive, there are several possible causes, such as a persistent hymen
(requiring a veterinarianís intervention), too
much fiber covering the vulva which thwarts the
maleís efforts to penetrate, and a number of
serious obstructions which may not be readily
If a proven female is not conceiving and the
service sire is impregnating other females in a similar time frame, first study the femaleís
reproductive history. She may be a "slow" or
"problem" breeder. Some females conceive steadfastly every year shortly after giving birth,
while others consistently take a couple months or more to conceive. In addition, problems
such as dystocia in the previous yearís birth
may have compromised the animalís reproductive soundness.
A very common cause of a failure to conceive in proven females is the presence of a uterine
infection. An infection can make the uterine environment inhospitable for a fertilized egg or
developing fetus. Typically, the first indication of an infection is that the female will ovulate
(indicated by rejecting the male for 15 to 20 days following breeding), but be receptive to
breeding a short time after this period. She is clearly cycling, but not conceiving. There may be no
discharge or other overt sign that there is an infection. A uterine infection can be diagnosed by an
experienced camelid veterinarian by culturing the uterus. Commonly, a uterine flush (or wash) is
performed and the female conceives a short time later. The trick in administering the flush is to
make sure the veterinarian passes the solution tube past the constricted cervix and delivers the
solution directly into the uterus.
Donít blame her; it could be his fault.
The author knows of a breeder who sold a perfectly good female for half price because the
female had not become pregnant after six months of interaction with his stud. He later found out
that his "stud" was infertile. The lesson here is that the male should never be overlooked when
sleuthing reproductive problems. Donít be fooled by loose advertising rhetoric. Understand that a
"stud" is an animal that has actually impregnated females. Glossy, full-page advertising and
aggressive promotion provides no guarantee that a stud is capable. Be sure to ask about a studís
Data from research supports the theory that alpacas with bigger testicle size are more potent and
more likely to impregnate a greater number of females as compared to alpacas with smaller
testicles. During formation of ARIís now defunct screening criteria, leading camelid veterinarians
concluded that adult male alpaca testicles should each have a minimum measurement of 3.5
centimeters longitudinally. It is recommended that you measure the maleís testicles and observe
them to be roughly equal in size and consistency.
After considering testicle size, one needs to consider the behavioral health of the animal. Does he
pursue females persistently, heed to spit-off, and only appear minimally distracted by males in
nearby pens? The male who is excessively aggressive or meek, easily discouraged, or obsessed
with the whereabouts of nearby males, may be an inefficient breeder because of his aberrant
There are other considerations when assessing male performance. Male fertility should be viewed
as a continuum with many variables affecting it. Most males are fertile, but some are more potent
than others. Secondly, there are environmental factors that can affect male performance and
fertility. There have been instances in which males suddenly became sterile after years of good
performance. In all of the instances known to the author, a scientific reason was forthcoming.
Possible causes for abrupt changes in performance include severe and prolonged heat, injury to
the testicles, or penis sheath/penis damage caused by fighting. Bouts with disease or other injuries
may also be the cause of the problem. Unusually hot weather leading to heat stress can render a
male infertile for 60 to 90 days. Spring shearing and implementation of other cooling measures
can reduce the possibility of lost performance caused by heat stress.
Mounting does not mean that penetration has occurred. Females with full coats on their posteriors
are more challenging to penetrate and more problematic for a male. A heavily wooled female may
simply be impossible to penetrate. Tail-wrapping or trimming the fiber from the tail and around the
buttocks allows for surer access. As a warning to the reader, be aware that there have been
tragic incidents in which the penises of stud animals have become ensnared in hair so badly that
the blood flow was interrupted and a portion of the penis was lost. One of the most prolific studs
in the llama business lost his reproductive capability due to this phenomenon. Occasionally, the
stud may simply have a problem with bad aim and release semen on the exterior of the female
after a lengthy mounting. If a male appears to have trouble finding the mark, make sure the mating
is done with good breeding symmetry and check and direct the male to enhance his performance.
If the male keeps repositioning, it may indicate that he is having problems penetrating.
Learn to meet the needs of young or aberrant animals.
Uninitiated males and maiden females can
present special challenges. Many problems can
be overcome by changing environmental cues
to get the desired response. Males, who will
mount females and each other at a very young
age, are incapable of penetration until about 20
months of age at which time their penises can
extend into a femaleís uterus. Testosterone
production is almost nonexistent in both male
alpacas and llamas prior to 18 months.
First-time males, who are physically capable
and willing to breed, are sometimes sporadic
performers, and are easily discouraged or slow
to begin orgling and pursuing. Often the
reluctant young males can be coaxed into
breeding by allowing an older male to enter the
breeding pen to pursue and mount the female
in close proximity to the youngster. Usually, the
young male becomes stimulated by his older
brethren and begins orgling and wanting to
mount. By the time the young male is fully
ready to breed, the female may have already
kushed, making the inexperienced maleís job
much easier. With the rigorous chase
component of the courtship completed, the
older male is removed and the younger male is
allowed to mount and breed. This technique of
supplanting a younger male in place of an older
male can accelerate the learning and
reproductive performance of a young male by
several months. However, there are limitations;
few males consistently breed before 22 months
First-time females are sometimes difficult to
read behaviorally. This can be frustrating for
the manager who attempts to monitor behavior
to assess receptivity or conception. Rejection
is obvious in an older female as evidenced by
body posture, threats and spitting at the male,
but a young female may do nothing more than
be reluctant or refuse to be forced down. Often young females respond as much to their lowly
social status in the herd as they do to the hormonal changes in their bodies brought about by
conception. A behavioral change, however subtle, may be the only visible indicator of a young
femaleís reproductive status. Young females sometimes will allow themselves to be bred after
they are pregnant probably due to submissiveness. Being attentive and ready to separate a
breeding pair, especially when the male is aggressive and strong, is often necessary when working
with young females. Because maiden females are often difficult "reads", controlling the male by
keeping him on a lead rope usually allows the handler to carefully assess the femaleís response
before she is overwhelmed by a more experienced partner. If she is given a few extra seconds to
muster a response to a male whose advances are controlled at the end of a rope, she is more apt
to respond to her hormonal message of being pregnant and reject the male.
Avoid breeding females too young.
Breeders wanting to maximize financial return may breed females when they are too young.
Females reach biological maturity between 12 and 24 months of age and occasionally not until 30
months. However, there have been rare instances of females conceiving as young as 5 months of
age. A conception in a female this young is undesirable and will endanger both the dam and cria.
Do not assume that a female weanling is safe from the interests of males sharing a common
A breeder may elect to breed a female based on her reaching a prescribed minimum body weight
of 88 pounds, or an age of 12 to 14 months, which is an age often cited in South American
literature. These weights and ages are helpful benchmarks, but they need to be considered in the
context of the South American setting where breeding is viewed as an annual event that coincides
with the three-month wet season. Because pastures are rich during the wet season and sparse at
other times, all breedings occur only once a year. Therefore, breeding can only occur at
approximately 12 months of age or not again until 24 months. Peruvian breeder, Julio Barreda,
believes that females bred at 12 to 14 months are at greater risk and more likely to lose their
offspring or their lives as compared to older females, especially if birthing occurs during a poor
wet season with marginal forage.
A survey of five longstanding North American alpaca operations found that the average age for
introducing females into a breeding program is 18 months, with individual animals being bred for
the first time from 15 to 30 months. In choosing a date for breeding, breeders considered the
femaleís behavior, the season, and the femaleís overall size and health. Generally, spring and fall
babies are desirable with spring babies carrying the highest preference. The well researched
book, Llama and Alpaca Neonatal Care (B. Smith, K. Timm and P. Long, 1996, Clay Press)
suggests waiting to breed females until they are between 15 and 18 months with a body weight of
greater than 90 pounds.
A somewhat different consensus is developing
in Australia and New Zealand regarding the
appropriate minimum breeding age for
females. Roger and Clyde Haldane, pioneers
of the alpaca business in Australia, regularly
breed females at 12 months providing they
show receptive behaviors and are
approximately 100 pounds in weight. The now
defunct New Zealand alpaca research station
at Tara Hills on South Island conducted
studies that support Haldaneís practice. In the
Tara Hills experiment, about 60% of females
conceived at 1 year of age. The Haldanes
believe that there are no adverse effects in
breeding yearlings provided the diet is of
consistently good quality. They also believe
that the lengthy (approximately 342 days)
gestation of alpacas allows the safe breeding
of yearlings because the developing embryo
does not grow rapidly until the last trimester
and the female is fully mature when she is
ready to birth. This practice, however, does
not address the nutritional demands and
stresses caused by lactation on the young female that is barely mature at the birth of her first cria.
Create the optimum breeding environment.
Breeding behavior is enhanced in the correct setting. People talk of romantic locations and
although the needs are different, a romantic setting needs to be set for alpacas too. A properly
constructed breeding pen in an area out of the sight of male groups and in a quiet part of the
property will enhance a breeding program. Minimizing distractions enhances performance. The
pen should be large enough to allow the customary chase, but small enough to control the
interaction and assure the female will interact with the male. The breeding pen should be flat and
free of obstructions. The male is most efficient on flat ground, centered over the female in a sternal
position. If the male has to
struggle to balance himself, he
may not achieve the desired
prolonged penetration. Sloping
terrain or a female too close to a fence for a male to mount her
correctly are common
contributors to compromised
Pre-breeding (courtship) and
rejection can be fast and
somewhat violent. Rejection
may include attempts to jump
the fence or push through a gap
in a gate. This can result in injury. The breeding pen should be strongly constructed and
built to prevent airborne departures or injuries caused by
legs and/or necks becoming
entangled in fencing.
After discussion of these reproductive problems, we must remember that most camelids breed
readily without human interaction. Our involvement should only enhance the process and correct
situations that are preventing speedy and efficient conception and reproduction.
© 2000 Eric Hoffman