Spring in the Riverina means cows are calving, groups are shifting weekly, and the feed run is getting longer every day. The paddocks are firming up after winter, but the alley distances are not getting any shorter. For a lot of operations in this region, the main vertical mixer is doing double duty: mixing rations and then grinding its way up and down every alley to deliver them. That costs more than most people account for carefully.
What it actually costs to run the main mixer the full circuit
A large vertical mixer is geared for processing. It runs a high-torque auger, drives a heavy planetary gearbox, and pulls significant hydraulic load just to keep the mixing system turning. When you take that machine down a 400 or 500 metre alley and back, you are burning tractor fuel and hours on an expensive drivetrain for a job that does not require any of that capacity.
On a commercial dairy in the Riverina, feed runs can go twice daily. Add up the tractor hours across a full year and the number is not trivial. Planetary gearboxes and auger bearings have finite service lives, and every kilometre of travel counts against them whether you are mixing or not. The machine that should be back at the bunker loading the next batch is sitting in first gear navigating a tight corner near the dry cow shed.
There is also the labour piece. A skilled operator who understands ration formulation and ingredient sequencing is valuable at the mixer. They are less valuable driving slow laps of the property. As spring calving puts pressure on feeding schedules, that time gets even harder to spare.
Keeping the TMR intact between mix and bunk
Ration segregation during delivery is a real and underappreciated problem. Long-stem forages, grains, and wet ingredients separate when a load vibrates over uneven surfaces or sits partially discharged in a sloped box. By the time the last pen gets fed, what comes out of the door is not what the nutritionist formulated. Cows sort it further from there.
A purpose-built delivery wagon is designed around that problem. The loading height is kept low so the already-mixed ration drops in cleanly without dropping it from height and breaking particle structure. Discharge is fast and controlled, not a slow trickle that lets fine particles settle out first. The geometry of the box is matched to transporting a finished mix, not processing one. That distinction matters at the bunk.
There is more detail on how delivery affects ration integrity in an earlier piece on TMR quality after the mixer, which is worth reading before you decide whether the issue is in your mixing or your delivery.
The off main mixer workflow in practice
The setup is straightforward. The vertical mixer stays at or near the feed pad. It loads, mixes, and discharges into the delivery wagon. The wagon then handles the alleys. The mixer starts its next batch while delivery is underway. That sequencing is where the throughput gain shows up, particularly when you are running two or three ration groups and calving has added a fresh cow mob and a hospital pen to the schedule.
The mixer does not idle. The tractor on the mixer does not clock up hours on delivery runs. If you are running something in the 18 to 21 cubic metre range, keeping it on batch duty rather than alley duty can add one or two additional batches to the day without extending the total time the operator spends on feeding. For a 300-cow operation heading into peak lactation, that matters.
For operations in the 150 to 300-cow range, the 10 cubic metre vertical mixer is often the primary unit. Pairing one with a delivery wagon of matched capacity keeps the system balanced: the mixer is not waiting on delivery, and the wagon is not waiting on a slow mix cycle.
Trailer versus custom box: the spring calving question
When cow numbers climb through spring and delivery distances stretch, the standard 25 Series delivery wagons handle most situations well. The LEO Agriculture 25 Series runs from 12 m³ (425 ft³) up to 18 m³ (636 ft³), with loading heights between 2.31 m and 3.04 m and maximum payload ratings from 3,800 kg to 6,400 kg. Those specs suit most commercial dairy layouts in the Riverina without requiring a semi-trailer tractor to pull them.
But there are operations where spring peaks push the numbers hard enough that a standard wagon becomes a bottleneck. If you are feeding 800 cows across six groups, and the fresh and transition groups need different rations delivered first, a 12 m³ wagon means more trips. The math changes.
For those situations, larger custom delivery boxes in the 28 to 40 m³ range are available on request, in either trailer or truck-mounted configuration. A truck-mounted box running a fixed route through the shed can dramatically cut cycle time when the alley layout is regular and the operator knows the circuit. Trailer-mounted versions offer more flexibility if the operation’s layout changes seasonally or if the same unit needs to move between sites.
The right choice depends on alley width, available tractors, how many ration groups you are running, and whether you can justify a dedicated delivery vehicle in the budget. There is no universal answer, but the worst outcome is undersizing the delivery capacity and letting it constrain a well-sized mixer. The reasoning behind getting mixer capacity right in the first place is covered thoroughly in a piece on running an 18 m³ mixer across multiple ration groups, and the same logic applies when you are sizing the wagon to sit behind it.
Practical considerations before the spring rush arrives
Lead times are worth thinking about now. Orders placed in late winter generally arrive in time to be operational before calving peaks. Waiting until you are already behind on feed runs means you are making a capital decision under pressure, which is rarely the best time.
A few things worth checking in your own setup before spring:
- How many kilometres does the main mixer travel per day on delivery, and what does that convert to annually in tractor hours?
- Are your bunk observations showing sorting behaviour that could be linked to segregation during delivery rather than a formulation problem?
- How many ration groups will you be running at peak spring calving, and can a single delivery wagon handle the sequence without the mixer sitting idle between batches?
- Does your alley width accommodate a 3 m loading height on the larger 25 Series wagons, or would a lower-profile option fit the shed better?
Running an off main mixer delivery system is not a complicated infrastructure change. For most operations it is a tractor, a wagon, and a revised daily routine. The complexity is in the sizing and sequencing decisions, not the equipment itself. Get those right before the cows do it for you.
