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Even when scanning percentage is 200+%, the 5 Stars still out perform

Case Study: John Renehan, Johnstown, Co. Kilkenny; Violet Hill Flock

The Violet Hill flock is run by John Renehan who runs a flock of 70 Pedigree Belclares and 45 Pedigree Texel ewes alongside a flock of 310 commercial ewes. John splits his lambing period between early and late, and the graphs below contains the scanning results of his early lambing Belclare flock.

As was seen in earlier case studies the 5 Star Replacement ewes have outperformed the lower indexed ewes in the flock, with an extra half a lamb between the 1 Star Replacement ewes and the 5 Star Replacement ewes.

John commented that “That looks very impressive . I’m very surprised for a genetically prolific breed to still have a difference of 0.5 of a lamb between a 1 and 5 Star Replacement ewe . It really solidifies the €urostar indices.”

Remember, even if you are a commercial farmer who doesn’t have €uroStars available on the ewes in your flock, if you consistently select your flock replacements bred from  4 and 5 Star Replacement rams then the breeding potential of the ewes in your flock will also gradually increase along with the profitability of the flock.

In this case John has ended up with a scanning percentage of 200+%, but it must be taken into consideration that ewes were in ideal condition at mating and are from a very prolific breed. If a commercial farmer was to start using 4 or 5 Star Replacement rams to breed replacements in their flock the scanning percentage will not jump significantly in a year, it would gradually increase over time, allowing farmers to hit the target scanning percentage that best suits their farming system.

There are 48 ewe scan results included in the below graphs. While the 1 Stars have outperformed the 2, 3, and 4 stars in this case, there is still a clear trend that ewes with high Replacement star ratings are having more lambs.

Scanning percentage per Replacement €uroStar

In this second graph we take a look at the average ewe Replacement index for the empties, singles, twins and triplets respectively. This is a more precise measurement than the €uroStars and is also displayed on the €uroStar sales catalogues and on the Ram Search bedside the €uroStar ratings. In this case there was only one empty ewe, but it is worth pointing out that she had already been given a poor Replacement Index, and this has been seen in previous case studies also.

The Replacement Index has very accurately predicted the ewes performance at scanning, with empty ewes having an average index of €-0.34 and the triplet bearing ewes having an average index of €0.35
The Replacement Index has very accurately predicted the ewes performance at scanning, with empty ewes having an average index of €-0.09 and the triplet bearing ewes having an average index of €0.30
VIOLET HILL BéLA (IE042821309437D) who is one of the Violet Hill Ram team this year. He was also used in the Central Progeny Test with his first progeny hitting the ground in 2017.
VIOLET HILL BéLA (IE042821309437D) who is one of the Violet Hill Ram team this year. He was also used in the Central Progeny Test with his first progeny hitting the ground in 2017.