Selecting a Stud Male for your Female

Why do we bother to “select” a male to breed with our females?

In truth any male will breed but we are seeking a mating to our female that will show improvement upon her in her offspring. To do that we have to consider what we have in her, what are her strengths and weaknesses? She is unlikely to be conformationally perfect, and her fibre characteristics probably improvable.

Is she long or short legged; fine boned or heavy boned; what are her proportions and balance and are there correctable faults or characteristics displayed which we will need to have 100% perfect in our male to effect a correction in the progeny? What is her fibre like? Is it unimproved or well structured; does it lack density or lustre and so on? So many questions to consider and choices to make!

It is further complicated by the fact that phenotype, what we see, is no guarantee of genotype. There are always surprises in store. The genotype of an alpaca is only revealed with time and breeding.

With a herd like Bozedown Alpacas the stud males are bred to many females and by examination of their progeny we begin to reveal their genotype. The most important truism that counts is, “Quality Matters”.

So we need a selection of males of high quality from which to make a choice that complements our female. To improve we need to use animals that exhibit superior characteristics. The rate at which the superior trait is passed on depends upon its heritability. If heritability is 50% then the effect upon the progeny is only one half of the observed superiority. The change can be progressive but has to be maintained. It obviously makes no sense to use a male animal with faulty conformation as if the fault is passed on, it sometimes can be difficult or impossible to remove later. Many physical traits are lowly heritable so trying to improve poor conformation can be time consuming and unsuccessful.

It is essentially a waste of time. The screening of alpacas for faults by breed societies or individuals is therefore an important exercise in order to eliminate poor physical traits, before we even consider breeding.

We can be more certain of building progress when we are able to use males that exhibit “dominance”. When a male exhibits dominance, depending upon the level, his progeny are consistent in presenting his superior qualities. This makes him a valuable animal as his performance is to some extent guaranteed. Strong dominance will stamp his “look” upon progeny for all to see; he certainly justifies his stud fee! Look about you and you will see examples of dominance displayed in the Bozedown herd. The use of progeny testing is the only sound way of measuring the superiority of one male animal over another. Anything else is largely guesswork!

Given that our animals are physically sound we are fortunate that the “quality traits” that we seek to employ have reasonable levels of heritability. Fibre density, diameter and weight are all moderate to highly heritable and therefore we are rewarded with relatively quick and obvious improvements.

Fibre quality is very important but complicated to define. There are several parameters that measure fibre quality; some are quantitative i.e. measurable, others are subjective and can only be felt. There is a tendency to concentrate upon the measurements and to ignore how it feels. How fleece feels is called “Handle”.

Fibre density can be measured but is difficult. A good indication of density can be made both by opening the fleece and exposing more or less skin depending upon density and the resistance to pressure felt when compressing the fleece. Obviously high density leads to high total yield of fibre at shearing.

The measurement of a fibre’s diameter gives an indication of fineness and probable softness. The measurement of groups of fibres indicates both the mean fibre diameter and the range of fibre diameter about that mean, an indicator of uniformity. We also measure the percentage of fibre above 30 microns as an indicator of the presence of coarse hair and potential for prickle in a garment. Fineness of fibre is important as the intrinsic value in a fleece is linked to its fineness and softness.

So we have three main parameters by which to judge fleece quality: fineness, density, and handle. I have put them in the order of importance as I see them. They are not independent of one another and can confound each other. For example density can be gained at the expense of fineness and handle, but realises a greater yield. Some very dense fleeces can be reasonably fine but lack handle and lustre (shine), and that can be very important in how the garment made from it looks and feels to the wearer! It is a balancing act and usually improvement in a particular direction has to be taken in stages, building quality over time.

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