28 March 1997


With the winter feeding programme finished and cows back out to grass, now is the time to weigh up the performance of the old diet feeder and contemplate whether a new model might be on the cards. Peter Hill prepared this buyers guide to makes, models and designs available.

COMPLETE diet mixer/feeders come in all shapes and sizes as manufacturers have sought to find better ways of preparing, mixing and dispensing forage-based rations.

Reliability is an essential ingredient given the key role and often heavy workload of such machines and, arguably, simpler equals better in this respect.

However, build quality and material specification also have a bearing on this aspect and, as long as they are well built, a more complex piece of machinery can be just as reliable, if requiring a little more maintenance.

The type of machine chosen will, to some extent, be influenced by the type of feeds used. Most machines now include some form of slicing mechanism to reduce the length of forage but not all will happily cope with a well consolidated silage block, let alone an entire bale. Others will, however, as the accompanying equipment details indicate.

Designs for ingredient mixing equipment essentially fall into one of four principal types:

&#8226 In-line paddles (as on the Keenan FP, Reel-Auggie and West Mixer-Feeder) create a tumbling action; low power requirement and simplicity are main attributes, though if the mechanism needs to be operating while the feeder is loaded, two tractors are needed for the job. Twin augers on the side of the Reel-Auggie pre-process forage before it enters the main mixing chamber.

&#8226 Angled sweep paddles (Hi-Spec MixMax, Redrock Diet Mixer, Star Super-Mix and West Unique Feeder) have a similar action but also circulate ingredients around the tub and often have more aggressive slicing knives.

&#8226 Auger mixers (Storti Bulldog, Seko Samurai, Kuhn Euromix, Kverneland KD 500-Series and Star Super-Mix G-Series) can be filled and then operated by the same tractor under most circumstances and circulate ingredients around the tub to achieve a good mix. With blades on auger flights, slicing of forage is achieved at the same time and some machines will take a whole straw or silage bale.

&#8226 Vertical tub machines (AGM Leader Unifeed and Shelbourne Reynolds Power Mix) will also take whole bales which are quickly reduced by aggressive slicing blades on the vertical tapered auger that also mixes other ingredients into the forage.

The way feed is dispensed needs to be considered in relation to the layout and dimensions of feed passages, barriers and troughs. Keenan, West and Redrock machines dispense from a high point so that the elevators (involving extra cost and components) needed by others are unnecessary in most situations.

Most discharge from the front or near-centre of the machine, usually to the left side. However, Redrock offers a right-hand option, as well as rear mounted conveyors which helps when feeding in a dead-end passage.

Keenan also offers rear feed conveyors while the two vertical tub machines feed to either side using a hydraulic drive conveyor across the front – or optionally across the back, in the case of the Unifeed.

In terms of capacity, volume is a slightly misleading measure given that the mixing system components and the way they work can derate a machines theoretical volume; a better gauge is the number of cows that can be fed per fill which, after all, is what influences work rate and the size of machine needed.

And, given that feeding a complete diet or total mixed ration is something of a technical operation, access to nutrition advice through the purchase of a feeder may also be a significant influence on the choice of machine.

Hi-Spec BaleMix is designed to take whole straw or silage bales. Giant slicing/mixing auger of Hi-Spec BaleMix is complemented by rotor knives and fixed counter blade comb.

Kuhn Euromix comes with standard observation ladder and weighing system. Inside the Euromix is a bladed main slicing/mixing auger, plus auxiliary mixing and circulation augers.

Kverneland KD 500-series has an inlet for introducing minerals and other bagged ingredients at ground level. Four augers aim to do a thorough mixing job on Kverneland KD 500-series feeders.

Keenan FP feeders high-level discharge means there is no need for an elevator. Tumble paddles and fixed knives for slicing forage are found inside the Keenan FP.