Three gold nuggets from 2025
Rather than write an article about a single topic, for a change I thought I’d share with you three little nuggets we collected last season. I hope you enjoy them!
MINDSET SHIFT
One of the coolest nuggets to come from our Wingman farmers last season was been watching their mindset shift from a Breed -> Bull-based conversation. Over the course of our interactions, farmers have realised that when we’re looking at their herd improvement strategy, they need to stop thinking about using a breed-based bull team (e.g. Friesian, XB or Jersey bull team), and actually start thinking who are the best INDIVIDUAL bulls are within that breed that will help drive their herd improvement strategy.
Being breed agnostic with your bull team gives you the opportunity to create some hybrid vigour in your herd e.g. low liveweight Friesian sire over Jersey X dams creates an awesome 500kg F10J6 animal. Or you can do the reverse - a high liveweight Jersey sire over a Friesian X dam to create a J10F6 cross. Instead of selecting sires based solely on breed, try selecting them based on their liveweight and other useful traits they might bring to the table. Knowing what your optimum herd liveweight is, and selecting a bull team that is breed agnostic to help you achieve that is absolutely key.
BASE COW UPGRADE
This created a fair amount of consternation amongst farmers who watch their herd’s BW/PW like a Hawk! I thought industry did a pretty good job of explaining it, but I saw people get a bit hot under the collar because all the numbers associated with their herd changed overnight and they thought their herd had gone backwards. The most important piece to understand in all of this was that although the numbers attached to individual cows might have changed, their RANKING did not – “the genetic base cow changes BW to reflect the positive genetic gain but has little to no effect on the BW ranking of cows. A base cow change doesn’t affect which bulls you are going to use, and it doesn’t change the cows you are going to keep.” (DairyNZ website). In effect, your best cows are still your best cows, and your worst cows are still your worst cows.
Speaking of worst cows, everyone now has more negative PW cows after the ‘Base Cow’ upgrade from a 2005 cow to a 2015 cow. However, the link between the Base Cow upgrade and PW was not well publicised (if at all). My guess is that industry inferred that because there were changes to BW, then there would be changes to PW as well. I was a little disappointed that nothing was mentioned in this respect, which is possibly related to the entity that ‘owns’ the PW index. That’s a story for another day however.
Simply put, the five traits that make up PW (Fat, Protein, Litres, LWT and SCC) are also a part of BW. It stands to reason, then, that if the values of those traits changed in BW after the Base Cow reset, then they would alter PW. As a consequence, everyone now has more negative PW animals. The rankings haven’t changed – the poor cows are still the poor cows – it just looks bad when farmers were feeling like they’d got on top of low PW cows and then the goalposts go and shift!
EFFICIENCY AND LIVEWEIGHT
An interesting phenomenon that occurs with alarming regularity is everyone’s most ‘efficient’ cow usually weighs LESS than a herd’s average for liveweight (sometimes by as much as 10-15kg). This is calculated VERY crudely by looking at the top 10% of animals on a PW basis, and then comparing their average liveweight to the rest of the herd.
One theory I have about this phenomenon is that the no-choice ‘team’ approach (whereby a range of bulls creates a team average) has created more outliers in the population in all traits – particularly for udders and liveweight. Whilst the liveweight of the team might look ok on paper, there is very little ability to optimise the liveweight for any given mating on any given day. For example, a big bull over a small cow works great in terms of the next generation’s liveweight, but a big bull over a big cow does nothing other than increase the daily maintenance requirement and possibly reduce efficiency on a kgMS/kgLWT basis.
The difference between the most efficient cows and everyone else in the herd tends to be higher in Friesian herds because of what’s called ‘liveweight creep.’ Over the last few years we’ve seen an insidious increase in the liveweight of the daughters from Friesian bulls, almost to a point where some of them are getting too big and are requiring more feed for maintenance as opposed to milk production. There was a 100kg difference in the liveweight of Friesian daughter-proven bulls in one catalogue last year – 100kg! How on earth are farmers meant to try and standardise their herd liveweight with such a wide range?!
This efficiency/higher PW is often offset by a slight reduction to fertility. Seeing elite, high PW animals with a lower Fertility BV relative to herd average is not uncommon; I can’t recall a single instance where the top 10% of animals in a herd on PW had a better average Fertility BV compared to the rest of the herd. Elite high-producing cows or not, we need to be taking fertility seriously in everyone’s herds – farmers can’t afford to have top cows dropping out of herds or being handicapped by a lower Fertility BV and struggling to get back in calf again.
And there you have it, three little nuggets from this season – 1) it’s not about the breed, it’s about the bulls WITHIN a breed; 2) the RANKING of your cows is more important than the number attached to them; 3) bigger isn’t always better – your SMALLER cows are potentially your most efficient animals.
