Update on breeding Objective
At the time of writing, (Oct 2020) we are debating whether to conduct another AI program. We are also considering how much focus we should place on fertility and carcase traits.
Mutton and lamb turnoff and prices are becoming much bigger profit drivers in our flock and we are believing we need to place greater emphasis on fertility and carcase traits. Our dog fences are giving us consistent excellent lambing results.
Currently we are increasing our focus on yearling bodyweights, meat yields and fat and muscle traits in addition to our wool and adult bodyweight traits. This will allow us to produce sheep that both produce valuable fleeces and also give us a valuable carcase in as short a time as possible.
The best science going on sheep breeding emphasizes the importance of using objective measurement of the key economic traits to identify the genetically superior animals in a cohort and then to use these better animals to breed the next generation.
Dunblane's philosophy is that the spreadsheet has replaced the sheep classer as the tool of the trade for accurate sheep selection. The hocus pocus of the sheep classer can't match the ability of targeted measurements, good scientific technique and spreadsheets to more accurately identify the best 1-3 rams in a group of 200 or the best 120 breeders in a mob of 1,500 maiden ewes.
Dunblane has been breeding and using our own rams for over 10 years. Our ram breeding nucleus is based on several AI programs using semen from Australia's most elite merino sires. Dunblane offers an opportunity for producers to access high quality genetics at cost competitive prices.
Our ram breeding program follows "world's best practice", as advised by Sheep Genetics Australia. Our selection program aims to maximize the genetic progress across our flock. We are aiming for sheep that will give us the widest possible margin between what price we receive for our wool and what it costs to produce, hence maximising wool profit for our wool producing business.
Rams are bred utilising world's best practice to achieve maximum genetic progress. Not only do we measure all the important economic traits of our sheep, we actually use the data extensively to ensure we are maximising genetic progress.
Dunblane has conducted several Artificial Insemination (AI) programs to import some of Australia's best genetics into our flock. Semen selected for our AI programs came from the top 1-2% of Australian rams identified through objective measurement. These individual rams all rank very highly on the Sheep Genetics Australia or the Central Test Sire Evaluation database.
Sires that we used include leading sires from Kia-ora, Hazeldean and Billandri. Our broad use of rams has minimised any risk that may come from inbreeding.
Ram Breeding Program
In 2009, we decided to breed our own rams because we wanted far greater control over our genetic destiny. For the commercial flock at Dunblane, we wanted rams of the highest possible genetic merit that would breed sheep that produced high value fleeces, were highly fertile, were easy care, were not susceptible to blowfly and produced wool at a very low cost of production. We were also aware of the increased value from mutton sales and wanted sheep that provided increased opportunities for our wethers and cull for age (CFA) sheep.
We have adopted all the various technologies such as electronic tags, stick readers, sheep handlers etc. to make the work of sheep assessment, data collation and selection both less labour intensive and more accurate. For example, all female and entire male sheep bred on the
property are tagged with electronic tags to maximise the genetic pool for assessment to in turn maximise genetic progress and to ensure ease of data capture and accuracy.
At this year's general shearing, we will side sample and fleece weight and body weight approximately 1,500 maiden ewes to identify the next 80 ewes as new entrants into the ram breeding nucleus. We use the Sheep Genetics Australia's RAMPOWER program for calculation of a 7%MP index on each of these animals so we can identify the top performing ewes.
Advice was sought on all aspects of setting up a ram breeding nucleus flock, including importation of external genetics, role of genomics, the use of Australian Sheep Breeding Values (ASBV) for internal selection of both males and females. SHEEP GENETICS AUSTRALIA, the Mackinnon Project and Anne Ramsay of Stenhouse Consulting have played key roles here.
We have seen considerable changes to our sheep since aggressively adopting these parameters and techniques. See Flock Performance.
Fertility is an increasingly important profit driver in merino sheep production systems. To achieve a high level of genetic fertility, we have placed selection pressure on the following:
- All young rams are critically assessed for testicle size
- The selection indexes we have used will improve our flock's fertility
- Our selection for lower wrinkle score and open faces will improve the fertility of our flock
- We have placed a moderate selection pressure on FAT and MUSCLE EBV's as these traits are associated with increased fertility in marginal environments
- Most years, we will sell all MA ewes following pregnancy scanning that aren't pregnant
Over the past 3 years we have marked >80% across the flock. Whilst much of this great result can be attributed to our wild dog exclusion fences built in 2015-2017, we are confident in the genetics of fertility in our sheep.
Easycare Sheep, Welfare, Blowflies and Mulesing
Dunblane ceased mulesing over 10 years ago.
Fly strike outbreaks represent a major animal welfare risk in sheep flocks. Blowfly strike can result in a significant workload and take a lot of profit out of a wool sheep flock. Reducing labour costs per DSE is critical to business profitability.
At Dunblane we decided that mulesing was not an acceptable way to protect sheep from blowfly strike. Hence we stopped mulesing 9 years ago.
We wanted sheep that are safe from the risk of fly strike and also required very little labour input during the production year.
To this end, we have focused on reducing body wrinkle and improving wool quality traits.
Nowadays our fly treatment equipment gathers dust in the shed. We are totally comfortable that there is very little risk from blowfly to our sheep and our business. We have received premiums for our non-mulesed wool in the market place and regularly see good competition for our non-mulesed wool at auction or on WoolTrade during flat or declining wool markets.
Our Top Sires from the 2019 drop
These top sires have delivered across the wide range of traits that we are measuring. The ram without a F on his side is a champion sire from 2 years ago.