REASONS FOR PERFORMING STUDY: Documenting the grazing and activity patterns of adult and juvenile horses will supply novel data that will inform the development of better pasture and land management strategies and provide insight into the high frequency of musculo-skeletal and foot problems that beset domestic horses.

GPS technology has enabled the collection of the required data with a degree of accuracy not previously available (Tomkins N. and Filmer M. 2007).

HYPOTHESIS OR OBJECTIVES:

• To determine the effect of paddock size and foaling on the activity level of mares.
• Provide a data base for comparison between domestic and feral mare and foal activity.

METHODS: Four domestic mares due to foal within 2 weeks of each other were tracked for 1 week in each of 3 paddocks (0.8, 4, and 16 hectares) to determine movement patterns and activity levels using a global positioning system (GPS, modified Wintec G-Rays 2). The same mares and their foals were again tracked (4 hectare paddock) for 1 week from the third day after foaling and again for 1 week (4.2 hectare paddock) when foals were aged 3 to 5 weeks. GPS data gave daily distance traveled and integration with Google Earth Plus (Google) provided aerial photographs of the subject paddocks with GPS data overlay. Aerial photograph grazing patterns were analysed visually and preferred paths were located using a handheld GPS (Garmin Rhino520 handheld mapping GPS, Garmin, USA).

RESULTS: Dry mare’s activity increased by 30% moving from a 0.8 hectare to a 4 hectare paddock (Table 1) and again by 18% when moved from a 4 hectare to 16 hectare paddock.

Daily distances traveled by mares prior to foaling ranged between 4.2 and 7.6km (mean 6km).

Mare activity increased slightly following foaling but 3-10 day old foals on average traveled further than their mothers (7.3km compared to 7.2km for mares).

On average foal travel did not change between 3-10 days age and 3-5 weeks age.

Mares underutilize some pasture areas and tend to travel on set paths.

GPS tracks overlaid on Google Earth satellite photograph.

• Green track represents movement in 4 hectare paddock
• Pink track represents movement in a 16 hectare paddock.
  

CONCLUSIONS & CLINICAL RELEVANCE: Activity levels of mares vary with paddock size. Distance traveled by new born foals in the domestic situation is similar to that of the mare. Foals are capable of traveling over 7 km daily within the first 3 days of life.

This movement may be important to stimulate the growth and adaptation of musculo-skeletal structures including the foot in the new born foal. Mares tend to select favoured pasture and tracks between pasture rather than utilizing the full paddock. Strategies for changing grazing and movement patterns can be investigated once a data base of normal activity is established.

Comparative data on activity levels of feral horses is being collected to investigate the potential activity patterns of the new born foal in a free roaming situation and the effect of variable activity levels and terrain on foot structure.