An inventory of grassland use on horse farms.

The research investigates how various factors affect grassland usage and contribute to horse nutrition on farms in Central Germany.

Research Purpose and Methodology

• The main aim of the research was to quantify the potential contribution of grassland to horse nutrition. This was accomplished by examining the seasonal variations in the amount and nutritional quality of herbage, or plant material that animals can eat, available in an inventory of six horse farms in Central Germany over 2019.
• The Compressed Sward Height (CSH) of all horse-grazed pastures were measured monthly and translated into Aboveground Herbage (AGH).
• This information was then used to divide different regions into short grass and tall grass sward areas. Sward is the name for the portion of grass within an area of grassland that is available for grazing.
• Apart from this, four pastures were singled out each month for collection of area-specific herbage quality samples.
• The researchers also used grazing diaries and questionnaires to study the farm-specific management practices in order to identify factors that could influence the amount and quality of herbage biomass.

Findings

• The proportion of short grass sward areas increased as the grazing season went on. This indicates that the grazing intensity or stocking intensity of livestock increased (p=0.0010). Stocking intensity, measured as Livestock Unit Grazing Days (LUGD), remained constant on most farms, despite changes in grass growth.
• Herbage Crude Protein (CP), Metabolisable Energy (ME), and Acid Detergent Fibre in the organic matter (ADF) varied among the grass sward areas. Crude protein and metabolisable energy are important for maintenance and pre-caecal digestible Crude Protein (pcdCP) could be provided during the grazing season.
• This indicates that grassland has the potential to provide sufficient maintenance energy (4.2 ± 0.32 – 8.4 ± 0.15 MJ ME kg DM) and pre-caecal digestible Crude Protein (pcdCP) (37.0 ± 3.86 – 77.4 ± 4.44 g kg DM) during the grazing season.

Conclusions

• The findings underscore the importance of giving incentives for grassland management to provide herbage among horse owners so as to optimize the potential of grassland during the grazing season.