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Twelve different families, mothering almost 1000 stud ewes annually, to produce true medium wool sheep. |
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Collinsville is run on a commercial basis comprising of 22,000 merino ewes producing 10,000 merino wether lambs |
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Collinsville’s cropping program consists of 3,500 hectares. This consists of wheat, barley, oats, canola, peas and lupins. |
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Irrigation program is run at North Booborowie and is mainly used to background wether lambs coming into the feedlot |
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Expanding operations in agricultural and station areas, and establishing lamb feedlotting for the domestic market |
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How much do you know about EBV's? Collinsville are enhancing their Estimated Breeding Values for clients. These figures will be on display at this years on-property sale on September 23rd 2008, so you may ask what is an EBV, how can it be reported and calculated and how do you go about using these EBV’s? We have given you a brief description about EBV’s which may give you a better understanding of the figures that will be presented to you on sale day and hopefully this will help you in choosing the right sire or sires for your mating program. What is an EBV? Estimated Breeding Values or EBV’s, are used to describe the expected genetic performance of an animal and are expressed as deviations from a whole group average. An EBV is the best assessment we have of an animal’s genetic merit. We can never know the true genetic merit of an animal because of the influence of environmental factors that can alter the expression of an animal’s genes. But measured information contains a lot of clues that can make our prediction very accurate. The information can come from direct measurement or correlated characters on an animal’s own performance, and from information on relatives. What EBV’s can be reported? Any trait that can be measured or scored can have a breeding value estimated. The common, and economically important, traits usually reported include fleece weight, fibre diameter, coefficient of variation for diameter, staple strength, body weight and reproduction rate. How are EBV’s calculated? If an animal has measured information on fleece weight, fibre diameter and body weight, it is possible to calculate EBV’s for each of these traits. Since an EBV is an estimate of genetic merit, we can take the phenotypic deviation for any trait and multiply by the heritability for that trait. For example; if an animal had a greasy fleece weight deviation of 120%, measured at 12 months of age the breeding value would be calculated by: +20 (deviation for GFW) * 0.4 (heritability for GFW) = +8.0 % breeding value for GFW
If more than one trait exists in the measurements, the genetic correlation between all the measured traits is used to further adjust the predicted value, until all the measurement traits in the data are taken into account. We can also use information on the early environment of an animal (birth date, type of birth and rearing, age of dam) to improve the prediction. But an EBV looks beyond the animal’s individual performance – it will also include the performance of all known relatives such as the sire, dam, progeny, half-sisters, uncle etc. Using EBV’s: For the ram breeder, EBV’s are very useful for comparing animals that usually cannot be compared on performance information alone, such as sires and dams and progeny. They can also be used to predict the value of animals from their pedigree alone by using the sire and dam EBV’s. But the greatest value of EBV’s is to the commercial ram buyer. Producers can purchase rams that have precisely the genetics they need. Because EBV’s are provided on a trait-by-trait basis, ram buyers can decide what traits they need for their operation and then find the rams that excel in those traits, knowing that they are comparing rams on their genetic value not on their environmental treatment. |
