New Genomic Predictors for Improved Reproduction03 December 2012
AUSTRALIA - Brahman herd profitability should rapidly increase during the next decade with the adoption of new genomic predictors for fertility, reports Meat and Livestock Australia.
Recent genomic advancements mean northern cattle producers are getting closer to having tools for improved fertility and animal survival.
Following seven years of Australian research, breeders can now identify bulls at weaning age, or even earlier, with strong reproductive traits.
Research Project Leader Dr Sigrid Lehnert, of CSIRO’s Livestock Industries’ division, told Meat and Livestock Australia that the new genomic predictors focus on both male and female fertility traits that lead to improved pregnancy and weaning rates.
“The northern cattle industry is committed to Brahmans because the breed is so well adapted to their environment,” Dr Lehnert said.
“However, Brahmans do have significant reproductive issues. It’s not uncommon for producers to have five-year-old cows that are pregnant with only their second calf. We’re aiming to genetically improve fertility so that cows raise more calves during their lifetime.”
Researchers found that reproductive traits such as age of puberty (age at first ovulation for heifers and, for bulls, scrotal size and semen quality) and length of the post-partum anoestrus (interval between calving and return to oestrus) are highly heritable.
“With genomically-enhanced estimated breeding values, producers will be able to select their herd bulls earlier in life without having to wait for other phenotypic indicators. Some selection decisions can be made at weaning, allowing for far more rapid genetic progress,” Dr Lehnert said.
The Beef CRC announced these genomic prediction equations at this year’s Beef Australia, saying they allowed development of genomically enhanced estimated breeding values (EBVs) through the Brahman BREEDPLAN analysis.
A genomic test for fertility in the tropical breed Nellore, is already available in Brazil. However, Sigrid said the test is not based on the very sophisticated phenotypic measures used in the Australian-developed model.
Further research Work by Australian beef researchers will continue to ensure the industry is able to tap into the advances made by genomic science.
“Reliable gene marker predictions for Australian beef cattle that can be made independent of pedigree are definitely a future goal of our research,” Dr Lehnert.
According to Sigrid, the genetic gains made during this project highlight the significant value of multidisciplinary, multi-organisational co-operation.