Genetic gain – are we squandering a great opportunity?

Ben Williams, Sustainability Manager UK and EU, Leprino Foods

Dairy production is a manufacturing industry. This is a statement that can spark all sorts of interesting discussions and debate. However, at its heart inputs enter the system, they are processed, and outputs leave. They are at least akin to a manufacturing system, if not a direct parallel.

In Manufacturing, the machinery of production is sought to be optimized through aligning with the pull of demand. Inputs and resources flow through the system and, upgraded machinery can increase throughput, boosting the productivity of the manufacturing system. If newer, faster machines are deployed, there is always a risk of underutilization of their true potential, if the surrounding production environment limits their capacity or creates ‘bottlenecks’.

The same challenge can be observed in dairy production, newer, potentially higher yielding animals are brought into the herd under the promise of genetic gain. This is measured by an increase in the Productive Lifetime Index (PLI) with lifetime being a key word we’ll discuss later. Bringing a high yielding cow into a system that has bottlenecks, means that the potential gain is often lost in the system. The dairy production system at its very core doesn’t really seem to recognise that risk, even the way farmers may introduce themselves, suggests that there is a lack of understanding value creation in the dairy system,

‘Hi, I’m Ben and I have 300 cows.’

In manufacturing that is weird, it’s not normal. ‘Hi, I’m Ben and I have 3 metal presses.’ Who cares? ‘I’m Ben and I generate £500,000 of revenue’, that’s an interesting discussion.

Starting to focus on yield or return, the value in production, is key to a ‘sustainable’ dairy system – Both profit and planet.

So, what constrains yield in dairy? Let’s look at the cow day (see Figure 1) a cow likes to lie down for 14 hours a day, feed for at least 6 (in lots of short breaks not one long feast), drink, socialise and display normal behaviour for another 2-3, leaving at best 1-2 hrs for everything else ‘we’ want to do to the cow including milk her. Any limitation on these values and the optimal environment in which to express behaviour is constrained. Losing one hour of lying time, loses a litre of milk, a mile spent walking to the parlour, loses a litre of milk, lack of optimized day night cycles to encourage lying, loses litres of milk. We often measure the optimization of a cow’s environment by access to grass or suitable housing. In both scenarios we may well limit the cow. In grazing scenarios, grass is a long way from the parlour, limiting intake, water can be at the far end of fields, limiting intake. In the housed system we use measures such as ‘stocking density’, the cubicles per cow to assess suitability however, having the right number, doesn’t mean they are suitable for the cow. We often see bed lengths too short, head rails too low and limited lunge space that leaves cows perched on beds rather than fully engaged. In manufacturing, if your workers were 140% more productive sat on comfy chairs you’d buy them the comfiest chairs. A dairy cow produces 140% more milk lying down than stood (McWilliams et al, 2022).

Let’s imagine the cubicles are plentiful, comfortable and at least close to feed (less than 10m), can the cow still get there or is access limited by one way in or out and a great big bully cow blocking? Is there enough feed face? Legal provision does not necessarily meet genetic provision. What about water? Again, legal does not mean palatable, at a high enough flow rate or accessible. A cow should not derive dry matter from the drinking trough. Limiting any one of these, creates a bottleneck and biological pressure on the cows. In a pressured system, we see distribution from the norm, some cows do well, often confirming our bias that we have succeeded in producing great cows, some won’t. These are our unproductive animals and ‘voluntary culls’, I suspect if you asked her, she wouldn’t class herself as a volunteer. Those are the cows ‘we broke’.

Surely this isn’t commonplace though. We all know ‘good farms’ with high yielding cows, those impressive operators we aspire to see more of. We have worked with some of our best operators to embed lean thinking into their management processes, centering the cow as the sole value creator on the farm. The result was a reduction in the cost of production (3-6ppl YOY), often due to increased literage or fewer losses for the same inputs. In essence optimizing the cow flow and environment to ensure they can realise their full potential.

So what? That’s easy to do, just takes experience/good advice/good collaboration with your advisors. Yet we still see the same rubbed necks, lame cows and poor retention rates across the sector. The advice for whatever reason is not being delivered, used or acted on. What’s more interesting is that the poor flow through the day-to-day environment is amplified by poor flow through the production cycle. Let’s be frank, in a production system the machinery of production has a finite lifespan, the same being brutally honest is true of a cow, they like us, will not live forever. Data provided for average UK lactation has moved between 2.8 (NMR) and 3.6 (BCBC) depending on your source and time of assessment (affected by milk price and cull value). Looking at when a cow reaches peak varies hugely by breed and system, but a 1st lactation cow is biologically limited to around 85% of an adult’s yield, in Leprino herds, peak lactation is seen around 3rd lactation with a stable curve to 6th and even 7th lactation before dropping back beyond 8th (see Figure 2). This tracks similarly to research by the likes of De Vries (2021) and Dallago et al. (2021) which suggests 3rd-5th lactation animals are the most productive and profitable of cows, before a loss of genetic gain (from lower replacement rates) and old cow costs start to affect the value of the cow. This would suggest that a replacement rate (allowing for TB losses, mortality and expansion plans) of 20% would be the most ‘sustainable rate of replacement (factoring in business performance and carbon footprint).

Leprino herds tend to operate a 32-38% replacement rate (the rate varies across the year depending on exits from block systems and all year round). This is a long way from the sustainable 20% figure and aligns with the 2.8-3.6 lactations we see of longevity. Again, so what? If we replace them, thanks to sexed semen, genomics and the ability to select bulls on a number of ‘proven traits’, what we lose in 3rd lactation plus cows, we gain in genetic potential. Each generation comes in better than the last! Or does it? And if so, at what cost?

Here is the first misconception, when we look at the impact of environment on potential, this is often set or limited by the calf facilities, the push for larger numbers of heifers, stretches the capacity of the calf rearing environment. What we find in Leprino herds is that the average 1st lactation animal yields around 75% of a peak 3rd lactation yield, not the realistically achievable 85%. As I shift ever more animals away from my peak yielding lactations (3rd-5th) and into my lower yielding 1st lactation animals (at best 85% of adult yield and more often than not, worse than that) I lower my total herd average. Not necessarily drastic but enough to lose litres in my tank equivalent to any potential genetic gain I would have seen. The cost of lost litres of milk, due to overproduction of heifers to Leprino farmers in Wales alone is circa £8.1 million per year (valuing milk at the long run average price of 30ppl). This is a lost opportunity cost, a value not seen on the books but there for claiming if we make the movement of animals in the system more efficient.

But genetic gain is permanent! Even if I lose in my 1st lactation, my entire system will catch up and see a step change in yield. The only permanence in any system is death! Death actively removes genetics from the system and of the heifers born into the system around 15% never make it to calve in, furthermore, a large number never make it to their second lactation. Going back to the measure of genetic gain – PLI, the key word is lifetime. We gain little to nothing if its dead. Even a heifer that has provided 1-2 calves before passing has likely passed you a compromised cow, into a compromised system. We know that genetic markers, epigenetics, are inherited and set not by genetic potential but by environmental pressure. Plus, a hope of reaching a newer, higher peak of milk from older cows is never achieved if you don’t keep them to beyond 3rd lactation (ideally an average of 5th). Replacing 32-36% of the herd means that ‘on average’ this is mathematically impossible.

So, we see a system in which innovation, of huge value – genetic gain, is squandered.

• Should we lambast the farmer for ineptitude?
• The genetics companies for a failure to support the farmer in using their product effectively, whilst pushing semen sales through advising unsustainably high replacement rates?
• The milk recording organisations that fail to provide data that gives any meaningful insight?
• The levy bodies with their KE events that teach the same tired tropes of sticky plaster solutions?
• The feed advisor, building designer that can’t make a bed the right length, or suggest the feed face is compromised?
• The dairy processor that pushes an assurance scheme that looks at paperwork and less at actual cow welfare?

The honest answer is all of the above. For whatever reason we have all lost sight of what drives value in our system – The cow. If we want to see true progress for better bank balances and a better planet, we need to improve how we manage our farming systems from the day to day to the strategic guidance and support. If we don’t, despite all the amazing technology at our disposal, there will be no change. In fact, we may as well pee into the wind.

References

Dallago, G.M., Wade, K.M., Cue, R.I., McClure, J.T., Lacroix, R., Pellerin, D. and Vasseur, E. (2021). Keeping Dairy Cows for Longer: A Critical Literature Review on Dairy Cow Longevity in High Milk-Producing Countries. Animals, 11(3):808.

De Vries, T.J. (2021). Digest Paper – Profitability And Efficiency Of The Five Lactation Average Dairy Cow. Available at: Digest Paper – Profitability and efficiency of the five lactation average dairy cow (cattlebreeders.org.uk) (Accessed on 26th May 2023)

McWilliams, C.J., Schwanke, A.J. and DeVries, T.J. (2022). Is greater milk production associated with dairy cows who have a greater probability of ruminating while lying down? JDS Communications, 3(1): 66-71.

The figures referred to in this paper can be found in the full Digest PDF, available to members in the Members area.