The Better Breeding Blog Breed Better Animals

Thank you for joining me!

The Better Breeding Blog will be an informative series of posts that will explain in layman’s terms the science of animal breeding and how to apply this to your own animals. This information is evergreen and applicable to all species, and if I can cut through the rather intense maths and genetics behind successful breeding such that pretty much anyone can understand it, then I will regard this as mission accomplished!

There are two planned sections for this site. This section, the blog, will be more “freeform”. I don’t want to be caught in analysis-paralysis working out the best structure for my posts, or how to best organise them from day one. I’d never get started! Rather, I’ll post on whatever comes to mind first, and allow things to develop naturally from there. The second section is intended to be more book-like, and will be the repository for a more organised structure where posts will ultimately be collated into chapters. This section doesn’t exist yet.

There may be an assumption that this site is biased towards alpacas, but I cannot stress enough that this blog is for all breeders of all animals. The science is exactly the same regardless of species, and I welcome and encourage all feedback and suggestions from serious breeders looking to improve their own stock and future revenues.

The following are all important considerations when undertaking a breeding programme:

Knowledge and Understanding of Genetics and Inheritance
To know and understand the fundamentals of genetics and inheritance—and ultimately, better breeding—is half the battle. The aim of this blog is to give you these.

Information
It is crucial to have good information on your animals, whether those you already have or those you wish to acquire. Good information requires meticulous record keeping.

Application of Theory
To know and understand a concept is all well and good, but the best breeders are the ones that apply that knowledge.

Commitment
Have a goal in mind, and stick with it. Determine what to you is the perfect animal, and set out to breed it.

Patience
Genetic change is slower than you may realise. Your perfect sire may not be born overnight, but if you commit to your plan and follow through one step at a time, you will create that animal with time.

Perseverance
There will be setbacks, and the desire to jump on trends and fads of the day will be strong. Just think of the hare and the tortoise and do not deviate. A sound plan will always prevail, though it may appear dull and boring to flighty trendsetters!

Probably the first two “sciency” words anyone learns when entering the world of breeding is phenotype and genotype. An animal’s phenotype is what we can see or measure—eg coat colour, wool length, milk production. Its genotype is its genes that create that phenotype. Dominant, co-dominant and recessive genes all factor in genotypes, and we’ll cover these in more depth later.

Another word common in breeding is trait. People often use the words trait and phenotype interchangeably, but they are really two distinct things.
A trait is something that can be measured or observed.
A phenotype is the value for that trait.

Examples:

• Staple length in wool animals is a trait, “110mm/year” is a phenotype
• Temperament is a trait, “placid” is a phenotype
• Milk production is a trait, “6,000 litres/year” is a phenotype

Another thing worth clarifying is that people also tend to use the word “phenotype” to mean appearance. Coat colour is a classic example of this type of phenotype, and probably the one “everyone” learns in high school biology. But phenotype can also refer to performance. Speed (eg of Thoroughbreds and greyhounds) is an example of this type of phenotype. So is milk yield. The words phenotype and performance are interchangeable when referring to measurable traits as opposed to observable ones.

To summarise:
If it can be observed, it’s a trait.
If it can be measured, it’s a trait as well.
The value of a trait is a phenotype, and a phenotpye can refer to appearance or performance.

One last point to make: an animal has as many phenotypes as it has measurable and observable traits.

Back in the Hello and Welcome! post I alluded to the intense maths behind successful breeding. Here is your first formula:

P = G + E

Scarey, isn’t it?! Though I stress that this is an oversimplified equation.

In words:
Phenotype = Genotype + Environment

In other words:
Phenotype is the result of genetic factors (the genotype) and nongenetic factors (the environment).

Not all phenotypes have nongenetic influences—a pup born with brindle coat genes is going to be brindle whether born in a temperate zone or the heart of a desert. But many phenotypes do, and this should be considered when embarking on a breeding programme.

Consider exceptional stud stock, known to produce high quality progeny over and over. Now consider those progeny raised during extensive drought with no supplementary feeding. Those babies have to-die-for genotypes (as evidenced by their pedigrees), but those genes won’t manifest as to-die-for phenotypes. Those babies will probably grow to be stunted, malnourished adults underperforming in the traits they were bred for.

An example is medium wool sheep raised in harsh conditions so as to grow (force) a lower micron fleece than their genotype would otherwise code for. The animals are not at peak performance, and while the wool will be fine[r], it will probably be brittle and susceptible to breakage when processed on high-speed industrial machinery. Compare this to genetically-fixed fine wool sheep consistently producing a low micron fibre of even diametre and strength in less harsh conditions.

E in the simple formula above is often taken to be physical environment. This includes availability of feed, feed quality, water quality, altitude, soil, and the weather and seasons.

But E includes more abstract factors which are also environmental (nongenetic) influences on phenotype. These are: fixed resources, management, and economics.

Fixed resources are such things as farm size, workable land and labour - can additional, more nutritional feed be grown to boost phenotypes for example?

Management is the farmer’s policies. Policies could include supplementary feeding, vaccinations and deworming to increase animal health, which in turn leads to more productive phenotypes. Or a breeder may introduce animals with better genotypes to his herd to improve future generations’ phenotypes.

Economics covers all farm inputs (costs) and outputs (prices for animals and their products). Feed, labour and husbandry inputs can all affect phenotypic outputs, which in turn influence prices obtained.

The goal of breeding is to improve phenotype by improving genotype, but there is more to this than simply cobbling together a pedigree with desirable ancestors. Remember that P = G + E, and neither G nor E can be taken in isolation on your quest for P nirvana. Rather, you need to consider an animal as part of a system, something we’ll go into more in the next post.

As seen in the Traits, Phenotypes and Genotypes post, genotype and environment both shape phenotype in many cases. Simplistically, G + E = P

Consider a farm. It has:

• animals
• farmer(s)
• a physical environment (altitude, soils, seasons, climate, water and pasture availability and quality)
• fixed resources (land size, workable area, labour)
• management policies
• economic inputs and outputs

The animals are the genotypic input, with the rest environmental inputs. All these parts interact and ultimately influence the end phenotypes.

When you have a group of parts interacting to create a whole, you have a system. Here, the farm is a system and the animals and environmental inputs are the parts of that system.

 A breeder strives to improve phenotype by improving genotype. But for maximum genotypic improvement, a breeder must also consider his animals as part of a system, subject to the interactions of other parts, and make decisions accordingly. And these decisions could be different for different breeders, as their personal systems also are different.

For example, alpacas in Australia occupy a wide range of temperate climates, and management practices change to suit. Paralysis tick can be fatal on the east coast if not controlled for, but not in the drier inland where it doesn’t exist. Shearing and birthing are timed, for the most part, earlier with decreasing latitude. It was not uncommon for breeders located in the subtropical north in the early days of the industry to relocate to the temperate south, having lost valuable breeding stock (genotypes) and their young to ticks and the vagaries of hot humid weather that set them back several years.

Nowadays most alpacas are found in the traditional wool sheep regions of the country. The environments favourable to wool sheep genotypes would appear to also be favourable to alpaca genotypes. The next four posts will go more deeply into genotype-environment interactions, and how knowledge of these can improve breeding programmes.