Principles

We believe the principles behind achieving genetic gain are relatively straightforward.

Be at one with your breederOne change deserves anotherBeware the non-genetic factor! It’s all about offspring’s potential Think up, link up!Compare, compare, compare! Avoid change for change’s sakeAll inheritance isn’t made equalKeep time on your side

If we’re honest, few farmers can ask themselves these questions and say “sorted!”. Apart from anything else, there’s seldom a finite end point in the game of genetic gain.

The four genetic cornerstones simplify the steps to achieving the gain a particular farmer or farm operation seeks. Then, sitting beneath each cornerstone are specific B+LNZ Genetics initiatives that collectively feed into the overall driver of using genetics to help lift farm profit.

From a farmer’s perspective, follow these four steps and you’ll be well on your way to finding the optimal ram or bull for your operation.

SOURCING INFORMATION
1 Focus on heritable performance

Cornerstone 1

Non-genetic factors have a bad habit of skewing decision-making away from the most important factor in ram or bull selection – the potential of off­spring. A highly rated ram for genetic potential for lambing percentage, for example, might have been born a single.

Or an animal highly rated for growth might have had a slow start as a triplet. Or, a bull could have great genes yet its productivity is permanently compromised by adverse events early in life. Favourable rearing and feeding can also inflate an animal’s own performance but won’t aff­ect its progeny’s potential.

These are all non-genetic biases and we need to be very wary of them! Non-genetic e­ects also vary between farms, between years and between animals within a flock within a year. When estimating genetic potential we need to see past non-genetic effects as much as possible – hence the importance of estimated breeding values.

Our top tips

  1. Buy rams or bulls based on the best estimates of the potential of their off­spring using estimated breeding values (eBVs). You may have to assess some traits yourself where there isn’t an EBV, e.g. structural soundness.
  2. The biggest animal on offer may not carry the best genes for growth. He may be the offspring of a mature mother with plenty of milk, born early in the season and experienced less disease challenge than that of other animals.
  3. Check that the genetic evaluations behind the eBVs are based on all relevant available information (across flock evaluation carries more power than simple within flock evaluation, for example).

Case study

Focus on heritable performance - Colin Campbell (right, pictured with Peter Tod)
I’ve had an unusual path to sheep breeding, which means few preconceptions! Along the way one of my missions was helping launch SIL.

B+LNZ Genetics initiatives

a) Developing breeding values (BVs) for important traits
Providing information on the traits ram and bull breeders are performance recording to guide farmers to breeders who are focused on improving the traits that are most important to their farm management and goals.

b) Establishing one source of genetic information
Improving the accuracy of SIL BVs by conducting all-SIL flock evaluations weekly, that remove non-genetic effects as far as is possible.

c) Introducing new traits related to farm profit
Introducing new traits to more completely define genetic merit as it affects farm profitability, including maternal longevity, maternal body condition score, and refining the breeding goals for carcase merit.

2 Work with a breeder who uses SIL or breedplan

Cornerstone 2

Genetic engines used by SIL and Breedplan remove considerable bias in estimating genetic merit. They take into account such things as the age of a mother and the fact one animal was born earlier than another, and (in the case of sheep) as a single or as a multiple.

It also helps by favouring an average animal from a very good family over the best animal from an average family. Although it’s almost impossible to get 100% accurate parentage on all lambs and calves born using field recording, new DNA tools are helping ensure near 100% accuracy for parentage.

Bias in genetic information can also be reduced if there are good genetic connections between flocks or herds, built by usage of common or link sires. This sort of good connection is imperative for breeders to benchmark their own progress and for sourcing outside genetics to maintain progress in their own breeding programmes.

Our top tips

  1. Seek out ram or bull breeders who record performance in the traits you want to improve, and who can provide estimates of genetic potential derived from measured performance data, or from DNA tests for key traits. Generally those using full DNA parentage testing can supply more accurate genetic information.
  2. Clearly identify those traits you know you can get BVs for and those that you can’t such as structural soundness (your ram or bull breeder will be able to assist with both).
  3. Well-connected flocks or herds (built on usage of common sires with other flocks or herds) rather than breeders solely breeding from within their own herd or flock can provide the best genetic information.

Case study

Work with a breeder who uses SIL or breedplan - Richard Scholefield
Some people feel estimated breeding values (EBVs) from a genetic evaluation system like SIL or Breedplan are an unnecessary complication, and prefer visual selection.

B+LNZ Genetics initiatives

a) Increasing the accuracy of genetic information
Promoting best practice in the management of breeding flocks and in the collection of performance data.

b) Strengthening genetic comparisons across populations
Building genetic connectedness through support of industry progeny tests and co-operative sire referencing schemes.

c) Using DNA to increase accuracy of genetic information
Increasing the accuracy of pedigree in breeding flocks and herds without having to DNA test every animal. At the same time, increasing the accuracy of breeding values earlier in the life of animals.

APPLYING TO FARM MANAGEMENT GOALS
3 Align breeding values to your farm management and goals

Cornerstone 3

Our aim is to help you match your farm goals with directly comparable breeding values (such as carcase weight by a certain date; lambing percentage; lamb survival). Keep in mind that change isn’t always good – it’s only good if you’re not where you already want to be.

For example, there may be no benefit in pushing lambing beyond 180% if that compromises other traits or makes management more diffcult. So the genetic goal for some traits may be “no change”. Consider, too, that good farm management obviously depends on integration of changes to genetics with other systems e.g. pasture management, subdivision, crops, and health regimes. Genetics is not a silver bullet providing the sole route to performance improvement.

Remember, heritability varies from trait to trait. The number of lambs born, for example, has low heritability, while carcase attributes have relatively high heritability

Our top tips

  1. Identify the traits you are seeking to improve and the degree of improvement you want from these traits.
  2. Consider other non-genetic based initiatives on farm (new pastures, subdivision etc.) to ensure they complement your genetic goals.
  3. Ensure your ram or bull breeder’s improvement programme is aligned with yours. Your feedback is important to the success of their business so give your breeder a clear understanding of your needs.
  4. Assess your breeder’s genetic gain trend line for traits important to you
  5. Identify the traits that may be important to you and which cannot be measured genetically (e.g. structural soundness) and work directly with your breeder on these.

Case study

Align breeding values to your farm management and goals - Gary and Elizabeth Basher
Gary Basher (pictured with wife Elizabeth) spent four decades developing Howard Head farm in Upper Moutere with a breeding programme to reflect a very particular environment.

B+LNZ Genetics initiatives

a) Linking genetics to farm goals
Developing tools that align farm goals with available estimates of genetic merit such as FlockFinder, a tool for a farm’s genetic plan and benchmarking of flocks/herds.

b) Promoting the use of total profit breeding objectives
Encouraging the assessment of performance in all key traits for a given animal type, which means buying from breeders who are measuring all key traits.

c) Developing indexes relevant to farm management goals
Developing tools to help those who want to improve some traits while holding others at an optimum for their situation e.g. fatness (body condition), maternal size or litter size in sheep. This means new indices that ensure farmers don’t ‘overshoot’ the optimum level for any particular trait.

d) Developing easy-to-use industry standard indexes
Promoting use of standard indexes together with a small set of key, marker BV traits, keeping genetic information simple, relevant and easy to use.

e) Developing online tools to aid ram and bull purchases
Developing decision support tools to aid ram or bull purchases. This enables benchmarking of actual flock or herd performance against its genetic potential and considers defined performance targets.

4 Achieve and monitor ongoing genetic gain

Cornerstone 4

It’s often said you can’t manage what you can’t measure – and for good reason! You know the BVs of the animals you are buying and where they sit in industry percentile band tables.

It’s now a matter of (i) ensuring future ram or bull purchases continue to advance the gain you want and that (ii) you’re measuring the benefits on farm with minimal bias.

To minimise bias from measures of your animals’ performance on farm it’s important to look at longer-term average changes because even over three years climatic factors can have a distorting e­ffect.

It also means matching genetic change with changes in management - better subdivision, better grazing management or more strategic use of fertiliser to exploit improved genetic potential.

Our top tips

  1. Look at the performance of your own flock or herd against appropriate industry benchmarks i.e. for similar farm types.
  2. Assess your rate of genetic change against industry averages and monitor change in relation to the targets you’ve set.
  3. Work closely with your ram or bull breeder to understand that your respective strategies for genetic gain are taking you both in the same direction. Ask for genetic trend graphs to assess this.

Case study

Achieve and monitor ongoing genetic gain - Renata Apatu, Ngamatea Station
For us there are two sides to achieving ongoing genetic gain – buying the genetics to achieve it and using kill sheet data to measure and monitor it.

B+LNZ Genetics initiatives

a) Presenting information on breeders’ genetic progress
Seeking information that shows the genetic progress a ram or bull breeder is making. This will demonstrate they are delivering on a breeding programme that can give ongoing value.

b) Investing in New Zealand’s genetic capability
Increasing academic resources to encourage and train future genetic specialists through supporting academic teaching and graduate students.