Location: Animal Genomics and Improvement Laboratory
Title: Implementation of Feed Saved evaluations in the U.S.Author
PARKER GADDIS, KRISTEN - Council On Dairy Cattle Breeding | |
Vanraden, Paul | |
TEMPELMAN, ROBERT - Michigan State University | |
WEIGEL, KENT - University Of Wisconsin | |
WHITE, H - University Of Wisconsin | |
PENAGARICANO, FRANCISCO - University Of Wisconsin | |
KOLTES, JAMES - Iowa State University | |
SANTOS, JOSE - University Of Florida | |
Baldwin, Ransom - Randy | |
BURCHARD, JAVIER - Council On Dairy Cattle Breeding | |
DURR, JOAO - Council On Dairy Cattle Breeding | |
VANDEHAAR, MIKE - Michigan State University |
Submitted to: Interbull Annual Meeting Proceedings
Publication Type: Abstract Only Publication Acceptance Date: 3/15/2021 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Feed efficiency is a trait of significant economic and environmental importance in the dairy industry. Feed costs can make up more than half of the total costs of dairy production. Improvements in feed efficiency can also have environmental impacts through potential reductions in manure and methane production, as well as reduced crop and land utilization. Measurements of feed efficiency rely on individual feed intake data; however, these data are expensive and time-consuming to collect, resulting in a very small phenotyped population. A concerted effort has been underway in the United States for over ten years to collect feed intake data in order to provide genomic evaluations of feed efficiency to the dairy industry. As a result of this effort, the Council on Dairy Cattle Breeding (CDCB; Bowie, MD) provided official evaluations for Feed Saved beginning in December 2020. Feed intake trials conducted during mid-lactation (50 to 200 days in milk) for a period of approximately 4 to 6 weeks in nine research herds throughout the U.S. have amounted to over 655,000 daily records of intake and yield. From these data, residual feed intake (RFI) is estimated with a linear model accounting for milk energy, metabolic body weight, change in body weight, and cohort effects. Current phenotypic data include 6,221 RFI records from 5,023 U.S. Holsteins born between 1999 and 2017 (as of December 2020). Phenotypic RFI are used to estimate traditional PTA in a linear animal repeatability model. Deregressed traditional PTA are then used to calculate genomic evaluations of RFI. These evaluations are combined with evaluations for body weight composite (BWC) to provide Feed Saved evaluations to the dairy industry. Progeny-tested bulls have an average genomic reliability of 38% for Feed Saved. Comparatively, young bulls have an average genomic reliability of 28%. Given the expectedly low reliabilities, a primary goal continues to be collecting additional phenotypes. Emphasis is also directed towards ensuring that phenotyped cows have close ties to current bulls actively used by the dairy industry. Participation in international collaborations will provide opportunities to further expand the reference population. In alignment with this, the next official evaluation (April 2021) will include phenotypic data from over 650 cow-lactations from three Canadian herds. Preliminary testing has indicated a 1 to 2% increase in genomic reliability from these additional data. Feed Saved is currently published by the CDCB as an individual trait. Future plans include incorporating the trait into an economic selection index. |