Four new Herefords Australia version 6 BreedObject selection indexes are to be released in mid-October with the publication of the October 2019 Hereford BREEDPLAN analysis. Herefords Australia, along with staff from the Animal Genetics and Breeding Unit (AGBU) and Southern Beef Technology Services (SBTS), have finalised development of these selection indexes following approval from the Herefords Australia board. Earlier breeder feedback gathered via the recent Herefords Australia member survey has also been incorporated into the development of these new selection indexes. This feedback ensures that the new selection indexes are representative of the varied production systems that Australian Herefords are run in, including both straight-bred and cross-bred production systems.
Each of the new selection indexes describes a different production/market scenario and relates to a typical commercial herd using Hereford bulls. Producers are advised to use the selection index that most closely aligns to their production system. All four selection indexes are focussed on maintaining and improving eating quality. Significant premiums are applied for increasing marble score up to a marble score of 3. Pressure is also applied to early life growth to maintain low ossification scores and good MSA compliance. In addition, each selection index targets the following specifications.
Southern Self-Replacing Index – Estimates the genetic differences between animals in net profitability per cow joined in a commercial self-replacing purebred Hereford herd targeting the domestic market. Daughters are retained for breeding and so maternal traits are of importance. Steers are slaughtered at 18 months of age to produce 300 kg carcases with 10 mm P8 fat depth. A moderate cost is applied for cow feed costs during the annual feed shortage period which results in small increases in cow weight.
Northern Self-Replacing Index – Estimates the genetic differences between animals in net profitability per cow joined in a commercial self-replacing herd targeting the domestic market. This index is suitable for use by both straight bred Hereford herds and in crossbreeding programs where Hereford bulls are being used over a Bos indicus based cow herd. Daughters are retained for breeding and so maternal traits are of importance. Steers are slaughtered at 18 months of age to produce 340 kg carcases with 12 mm P8 fat depth. A high cost is applied for cow feed costs during the annual feed shortage period which produces little change in mature cow weight.
Southern Baldy Maternal Index – Estimates the genetic differences between animals in net profitability per cow joined in a commercial crossbred herd using Hereford bulls over Bos taurus females (e.g. Angus). A portion of the heifers are retained for breeding and so maternal traits are of importance. The steers and surplus heifers are destined for slaughter at 18 to 19 months of age. Steers produce 300 kg carcases with 10 mm of P8 fat depth, while heifers produce 270 kg carcases with 12 mm of P8 fat depth. A moderate cost is applied for cow feed costs during the annual feed shortage period which results in small increases in cow weight.
Northern Baldy Terminal Index – Estimates the genetic differences between animals in net profitability per cow joined in a commercial crossbred herd using Hereford bulls over Bos indicus females (e.g. Santa Gertrudis) where all progeny (male and female) are destined for slaughter. Steers and heifers are slaughtered at 18 to 19 months of age. Steers produce 340 kg carcases with 14 mm of P8 fat depth while heifers produce 300 kg carcases with 17 mm of P8 fat depth.
Further details will be made available upon the release of the new Herefords Australia selection indexes in October 2019.