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Joining in spring? Many clients join in spring, even though both ram and ewe fertility are lower at this time than in autumn. If joining in spring it is suggested that the rams be yarded with the ewes for some hours on a regular basis, early in the joining period.
Pre-joining Management: It is recommended that all ram treatments, including shearing, be completed 6 weeks before joining. A supplement of lupins over this 6-week period will improve semen supply.
Do You Have a Ram Paddock? Border rams are harder to keep in than Merinos. To ensure that they do not annoy the neighbours, particularly over the autumn when they seem to be most active in finding willing ewes, we recommend the use of a tightly fenced ram paddock.
Are Your Rams Fertile? A first stage check is to palpate the testicles with two hands. They should be a good handful in size, firm without being hard and with a modest sized epididymous at the bottom. A full test requires veterinary advice. There is a useful page at NSW Agriculture on this topic.
Poor Lambing Percentage? Poor lambing percentages are distressing, yet it is often hard to pin-point the reasons. It might be due to predation by foxes, poor conception by the ewes because of low body-weights, temporary heat-induced infertility in the rams, brucellosis in the rams, etc. There is more information on this topic at the NSW Agriculture website.
Why did that Ram die? Common causes of sudden death in rams, as in other sheep, are clostridial diseases, that are prevented by 5-in-1 vaccine. Wongajong Rams have been vaccinated twice as lambs, but still benefit from an annual booster. Rams also die from many other causes, including fighting, that are too numerous and complex to detail here.
Heliotrope poisoning: Heliotrope is a common poisonous weed that grows after summer rain in many regions. Borders are more prone to heliotrope poisoning than Merinos, because they eat it more readily than other sheep, so don't let your rams get too much of it.
Is this system of genetic specification being used in other animals and breeds? The system of calculating Estimated Breeding Values (termed Australian heep Breeding Values, or ASBVs) is the same as that used in most breeds of cattle (eg BREEDPLAN) and sheep, as well as pigs and poultry. However, the composite Dollar Index is set specifically for Border Leicesters.
Won't selecting animals by ASBVs lead to poor conformation? Separate culling of poor visual traits is needed, together with positive selection for good ASBVs. ASBVs can also be established for visual traits if they are recorded in a consistent way.
What is the Accuracy of ASBVs? For a single ram with a weight ASBV of +5kg (5kg heavier), the True Breeding Value may vary within a range of +3.4 to +6.6kg. In a group of 5 rams, this error is reduced to a range of +4.5 to +5.5kg, because some of the uncertainty cancels out.
What is the value of ASBVs to me? A ram with an ASBV of +5 for growth will breed lambs that are 2.5kg heavier (only half the genes of a lamb come from the ram). If the ram sires 200 lambs in a lifetime, this will amount to 500kg of extra lamb from that sire, above that from an unselected ram.
How can ASBVs be compared between flocks? This is done by the use of link sires, that are used in many flocks. All the $uperBorder$ flocks either use semen from common sires, or trade sires between their flocks. Neveretheless, it takes time to establish good linkages for traits such as Maternal weaning weight and Number of Lambs Weaned, because these traits need to trace pedigrees over 3 generations. These linkages will get better with time.
Can the ASBVs and the Dollar Index be compared across maternal breeds? It is an ideal to do this in the future, but it is not yet operating.