As anyone who has watched their waistline expand from “30-something” to “40-something” will tell you, some things should never be measured. On the other hand, measuring as part of research efforts like the Efficient Dairy Genome Project – aimed at enhancing feed efficiency and reducing methane emissions in dairy cows – is vital for expanding our knowledge.
“We are working to get a better picture of how rations and ration components work with the genetics of our research herd,” said Dave Seymour, a Ph.D. student at the Centre for Genetic Improvement of Livestock, Department of Animal Biosciences at the University of Guelph.
Crunch time
With his expertise in animal measurements of feed efficiency and its use, Seymour knows that crunching the numbers is critical to success.
“Right now, I’m helping with phenotyping the animals at the research facility, such as the measurement of methane emissions,” said Seymour.
“Once we get enough data, I will handle most of the analysis in calculating residual feed intake (RFI) or feed efficiency.”
It sounds easy enough, until you actually go to do it.
“To determine RFI we gather the daily feed intake of all animals and include other factors like growth, body weight and milk production. Then we look at where all the food is going: Is it to milk, body mass or somewhere else?”
After that, they compare the animals and compute an average feed intake for all combined sources. Animals who eat less than average have a low RFI and thus are more efficient.
They test the animals at a specific stage in their lactation which equates to roughly 150 days in milk.
“That is mid-lactation which is a more energy neutral stage where milk production is just starting to come down. There is an energy balance at that point so it gives us a better idea of the average energy requirement of the animals, which in turn relates to feed intake and feed efficiency.”
Model behavior
Where it gets interesting for industry is the next step in the process.
“That information can inform different statistical or breeding models to identify the best animals for breeding selection. Since all the animals are also being phenotyped, we can see what areas of the genome are most linked to feed efficiency and incorporate that into breeding programs.”
Oh, and then there’s the little matter of saving money for producers and playing a part in saving the planet.
Milked by taxes
“Right now, we don’t have a methane tax like we do a carbon tax, but I think that’s a real possibility down the road. Already there is concern about the environmental impact of dairy production in Canada.”
By increasing feed efficiency, though, not only will the producer’s feed costs go down, but methane emissions will also be lowered. In Seymour’s view, it’s a classic “win-win” scenario.
Still, there’s a lot of work ahead to get to that point, but Seymour is pleased with the progress thus far.
“For methane emissions, we have been testing about two cows a week, four times a day from Monday to Friday. So far we have around 50 animals tested and hope to have about 200 by the time the project wraps up next December.”
All that measuring takes time and effort. For researchers on the Efficient Dairy Genome Project, though, it’s time well spent. Unlike measuring your waistline, science is one area where ignorance is never bliss.
