Biological hay preservative for mould control and high-quality feed

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Adding a biological hay preservative to hay and straw inhibits the yeasts and fungi that can lead to spoilage and poor-quality feed.

BioStart HayKing is a combination of fermentation extracts that inhibit hay decomposition microbes – ensuring bales store better, remain cooler and result in better feed.

Our biological hay preservative inhibits the growth of the yeasts and fungi that use up feed energy, heat bales and produce mycotoxins that affect animal health.

Designed and manufactured in New Zealand specifically for and with Kiwi farmers and contractors, HayKing comes in two forms:

  • An easy-to-store liquid that is applied straight from the can through one of our custom Ascot Pump applicators with in-cab control and volume monitor.
  • Granules applied through our Ascot Pumps Granule Applicator with in-cab control.

HayKing works best when used with good haymaking practices.  Only bale when moisture levels are below 24% and be sure to apply the correct rate of HayKing.


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Directions for use:

Accurately measure the moisture content of high moisture hay before baling using either a moisture meter or carry out a microwave test.  Do not use HayKing if moisture levels exceed 24%.

If crop conditions change, the application rate can be changed from the cab using a dash-mounted controller.  The controller enables you to regulate the application rate to meet light, medium or heavy crop loadings.

Bale size Minimum application rate
Conventional small bales up to 35 kg Moisture content 18% 15 mL per bale
Moisture content 21% 20 mL per bale
Moisture content 24% 25 mL per bale
All other bales: Per tonne (1000kg) rate Moisture content 18% 300 mL/tonne
Moisture content 21% 470 mL/tonne
Moisture content 24% 670 mL/tonne

Material Safety Data Sheet

HayKing Granules
HayKing Liquid

Label information

Download the product label here.


Handling precautions

When mixing or applying, avoid contact with skin and eyes. Wear protective clothing, gloves and goggles. Flush applicator thoroughly with water after use. Do not eat or drink while using. Wash hands and face before meals and after work. Wash protective clothing after use.

Storage instructions

HayKing contains fermentation extracts. Store out of direct sunlight and below 30ºC, otherwise, product efficacy may be affected.

Empty container disposal

Triple rinse and return to an approved recycling centre.

Label information

Download the product label here.

Empty container disposal

Triple rinse and return to an approved recycling centre.