Sheep Genetics (SG) is the largest and most comphrehensive accross flock sheep genetic benchmark in the world. Lambplan provides data services for the prime lamb breeds & Merinoselect serves the wool and sheepmeat industry based on the merino. There is significant overlap in carcase & disease traits which are common to both, still caution is needed when comparing different breeds of sheep.
Australian Sheep Breeding Values (ASBV's) are the common genetic language used.
Australian Sheep Breeding Value (ASBV’s) are provided in the Petali Merino catalogue for 9 important traits:
YWT - Body Weight (kg)
Rams with higher YWT ASBVs produce progeny that grow faster & are heavier at a certain age.
YCFW - Clean Fleece Weight (%)
Rams with higher YCFW ASBVs produce progeny that will produce more wool fibre.
YFD - Fibre Diameter (um)
Rams with more negative YFD ASBVs produce progeny which produce a lower fibre diameter wool.
YSS - Staple Strength (N/Kt)
Rams with more positive YSS ASBVs produce progeny that have higher N/kt.
YSL - Staple Length (mm)
Rams with more positive YSL ASBVs produce progeny that will produce longer wool fibre length.
YWEC & PWEC Worm Egg Count (%)
Rams with more negative WEC ASBVs produce progeny who have a higher genetic potential to resist worm burdens. WEC ASBV’s estimate an animal’s genetic ability for carrying worm burdens - a combination of being genetically less likely to pick up worms (resistant) and being able to cope immunologically with worm burdens (resilient). WEC ASBVs are expressed as a % relative to a count of 500 epg.
YFAT - Fat Depth (mm)
Rams with more positive FAT ASBVs produce progeny that are fatter. More fat is associated with higher reproduction rates, greater lamb & weaner survival. Ewes also lose less weight when nutrition is restricted.
YEMD - Eye Muscle Depth (mm)
Rams with more positive EMD ASBVs will produce progeny that have more muscle, independent of weight, plus higher lean meat yields. More muscle is associated with less worms & better staple strength, higher body condition & produce more twins.
EBWR - Early Breech Wrinkle
Estimates the breech wrinkle score for animals at lamb marking.
The Merino Production (MP) index rank animals on their ability to produce progeny for a fine wool operation that has significant surplus sheep sales. The index is aimed at producers whose sheep income is a balance of both wool and sheep sales.
Trait 10 yr $ Gain 10 year change
YWT 44% +8.2kg
YCFW 17% +8.3%
YFD 22% -1.1
YCV 17% -1.2
Other traits are measured or scored at Petali including Breech Cover & Dag.
If more information is required please ask or look up ASBV’s on the Merinoselect website www.sheepgenetics.org.au
Australian Sheep Breeding Value (ASBV’s) are provided in the Petali White Suffolk catalogue for 6 important traits:
BWT - Birth Weight (kg)
BWT estimates the genetic difference between animals in live weight at birth.
WWT - Weaning Weight (kg)
WWT estimates the genetic difference in body weight at weaning or 100 days of age.
PWWT - Weight (kg)
PWWT estimates the genetic difference in body weight at 225 days of age.
PFAT - Fat (mm)
PFAT estimates the genetic difference in fat depth at 45kg live weight.
PEMD - Eye Muscle Depth (mm)
PEMD estimates the genetic difference in eye muscle depth at 45kg live weight.
PWEC - Worm Egg Count (%)
PWEC estimates the genetic difference in worm burden at 225 days of age.
WEC ASBV describes the value of an animals genes for carrying worm burdens - a combination of being genetically less likely to pick up worms (resistant) and being able to cope immunologically with worm burdens (resilient).
The Lamb 2020 index has been developed to suit terminal sire breeders with clients targeting a 22 kg lamb carcass, from either a Merino or first-cross ewe base where worms may be a significant challenge to lamb production.
TRAIT Emphasis 10 year Change
BWT 8% 0.10kg
WWT 24% 2.7kg
PWT 25% 3.5kg
PFAT 9% 0.2mm
PEMD 22% 1.3mm
PWEC 12% -30%
If more information is required please ask or look up more ASBV’s on the Lambplan website www.sheepgenetics.org.au/LAMBPLAN
Ranking animals for each traits within the national flock is very important to successful selection & breeding. We can see if a sheep is in the top 10% of the breed (trait leader in blue) by looking at the percentile list.
Merino Percentiles list
Terminal Percentiles list
rank the ASBVs from top 1% to down to the bottom (100%).
Breech Wrinkle - EBWR
Early Breech Wrinkle (EBWR) and body wrinkle have an estimated heritability of 0.35, which is similar to body weight, staple strength and eye muscle depth. Environmental effects also have a significant effect on the expression of wrinkle, sometimes called ‘feed wrinkle’. For example;
twin born lambs are 0.3 to 0.5 score plainer than a single born lamb
maiden lambs are 0.2 to 0.3 score plainer than lambs from older ewes
drought lambs are 0.5 to 1.0 score plainer than lambs born in good feed conditions.
Accounting for these feed effects is one of the reasons why a Breech wrinkle ASBV has been developed. All Petali stud lambs are scored at lambmarking for Breech wrinkle. This is an ideal time to assess lambs & the development of the new ASBV is a very timely & valuable tool.