User:Rstephansen/sandbox

Introduction

The widespread use of genomic information in dairy cattle breeding programs has presented the opportunity to select for scares phenotypes of feed intake and feed efficiency. That means animals from research and commercial herds can serve as reference population to calibrate a genomic prediction equation. Genomic breeding values of selection candidates are then used to enhance genetic progress of feed intake and/or feed efficiency. Phenotypes for feed intake, however, are still an important limiting factor for obtaining high accurate breeding values and performing genetic analysis for feed intake and feed efficiency. Based on the experiences gained through several initiatives, we provide guidelines on the recording and handling of feed intake records for genomic and genetic evaluations.

Disclaimer

The fact that specific device manufacturers are mentioned in these guidelines is in no way an endorsement of the devices or their accuracy by ICAR.

Definitions and Terminology

Table 1. Definitions of Terms used in the guideline of recording feed intake for genetic evaluation

Term	Definition
DM	Dry Matter
DMI	Dry Matter Intake
EID	Electronic identification device
FS	Feed Saved
PMR	Partial mixed ration
REML	Restricted maximum likelihood
RFI	Residual feed intake
TMR	Total mixed ration

Scope

The scope here is to provide guidelines for of recording feed intake for genetic and genomic evaluations of feed intake and/or feed efficiency. Figure 1 illustrates the main elements of the guidelines and links for a detailed description can be found below.

Sub-sections

Links

Acknowledgements

Authors of the document are, in alphabetical order:

Maria Frizzarin, Teagasc, Ireland

Birgit Gredler-Grandl, Wageningen Livestock Research, Netherlands

Jan Lassen, VikingGenetics & Aarhus University, Denmark

Rasmus Bak Stephansen, Aarhus University, Denmark

Karoline Bakke Wethal, Geno, Norway