The first return on the financial – and genetic – investment in the ram comes from the slaughter or sale of his wether sons in late year two-early year three. Including the two pre-sale years the ram spent on the breeder’s property – since that’s where the ram’s genetic merit was determined – the average genetic and financial return period from offspring growth-slaughter productivity is four years (ie: the mid-point of years three, four and five).
As an aside, the same investment return period mentioned applies to terminal sire ram breeds because we’re only interested in lamb growth-carcase merit on all of their offspring.
Buying a dual-purpose breed ram means from one perspective we’re really making more of a genetic investment than a financial one. We’re investing in the inherited future reproductive and lamb rearing potential of the ram’s daughters and expecting them as a result to earn a positive financial return from lamb production throughout their lifetime on the farm.
Daughter productivity starts in year four when the ram’s first crop of two-tooth daughters are mated, lambed and weaned and ends in year 10 with the final sale of offspring from the third crop of daughters as mixed-age ewes. Obviously we’re interested in more lambs weaned per daughter and hence more lambs available for sale.
The total productivity of our ram’s daughters spans a six-year period (years five to 10) with an average return period of about seven to eight years (ie: the midpoint of years five to 10).
As a matter of interest similar daughter productivity calculations applied to dual-purpose beef cattle (such as Angus) and deer (Red) indicate an average period for returns on genetic investment to be generated over 11 and 12 years respectively.
The future repercussions of buying a ram are considerable, both genetically and financially. It can take quite some time before any potential benefit can be actually returned to a farm’s business. This reinforces the importance of what we’re looking for when buying a ram and what the potential of that ram’s genetics offer in terms of the bottom line when his daughters start producing offspring.
That goes for all maternal-type rams used in any given year. The higher their genetic potential for both offspring growth and lamb productivity of their daughters the better the investment independent of how long before that investment is fully realised.
I guess the biggest pity in many of New Zealand’s commercial flocks is that we don’t know the sires of each individual two-tooth ewe so we never know which sires in the team are the better earners genetically – and financially.
All in all it’s another likely case for the individual recording of animals in this country’s commercial flocks where the long-term value is highly likely to be worth the short-term cost.
Ramming it home
Years 0-1
Let’s assume the breeder performance records with SIL, the ram survives as a lamb and passes all structural and Breeding Value-index culling inspections prior to being put up for sale as a two-tooth.
Years 2-4
A commercial breeding flock owner buys the ram and uses him for three consecutive years.
Years 3-5
Being a dual-purpose flock the three crops of wether lambs by this ram are either sold store or slaughtered.
Years 4-6 – continuing through years 7-10
Ignoring hogget mating in the flock the retained two-tooth daughters of the ram are first-mated in years four, five and six. These ewes remain in the flock – subject to culling, deaths and so on – until age-culling after their fourth weaning. The last of the ram’s daughters are culled in year 10.
Years 5-10
All wether lambs weaned by the ram’s daughters are either sold or slaughtered.
