Constructing a good handling unit can cut labour hours by as much as 18% by allowing handlers to complete a variety of tasks efficiently and safely.
To achieve the best design, farmers are advised to visit other sheep farms to see handling systems in action, finding out what works and how things can be improved.
This is according to Teagasc sheep adviser Edward Egan, author of the Teagasc publication A Guide to Designing a Sheep Handling Unit (free PDF).
Below, Mr Egan addresses some key questions about designing a sheep handling system.
Animal behaviour: How to improve sheep flow
- Avoid sharp corners and dead ends in the design, as it is not good for sheep to lose sight of their flock-mates
- If your handling system requires sheep to turn 90deg when moving in groups, this is best done by using a gradual curve
- Sheep need to be able to see a clear route ahead of them to capitalise on their flight behaviour – use see-through gates to provide this clear route
- Sheep want to follow sheep, flock together and use similar routes
- Sheep can learn a handling system after three to four goes
- Use a non-return gate to stop sheep reversing back down the race (see Non-return ramp and forcing pen diagram)
Open sides: Where to place them
- Locate at the end of each race
- Locate at the end of each foot-bath
- Use see-through gates between pens where you want sheep to go
Solid sides: Where to place them
- Place to keep distractions out of sight
- Use them to focus sheep where you want them to go
- It is often good to have solid external boundaries, race sides and foot-bath sides
- If using timber, leave a 50-100mm gap between the lowest timber rail and the floor to assist drainage and slow the rate of rotting
- Use on external boundaries, race sides, between adjoining pens where sheep move in opposite directions, and to block the sight of sheep either stationary or being handled
Where should I locate the handling system?
- Sheep should easily flow from main paddocks into a holding paddock then into the handling unit
- Ideally, design a handling unit with entrance gates to three or four paddocks
- Adjacent roofs need working gutters
- Ensure a clean surface underfoot. Ideally, this is done by having entrances with 150mm hardcore topped with 100mm of 12.5-25mm round store to keep sheep clean and feet stone free
- The ideal collecting pen floor would have a bottom layer that is 150mm of compacted hardcore, a mid-layer of 1000-gauge polythene membrane and a top layer of 125mm of concrete
How do I design the collecting pen?
Collecting pens should offer easy access to paddocks, roadways, yards and sheds, which may also act as additional holding pens for large groups
The collecting pen’s role is ideally to hold all the sheep that will be gathered
It can be used in conjunction with a holding paddock (0.4-0.8ha) which should be obstacle free, well fenced and free draining
- Collecting pens should be 3-4.6m wide to prevent sheep retreating past the handler.
- The entrance gate should be 3-4.6m wide.
- Lowland ewes require 0.5sq m per ewe without lambs and 0.65 sq m per ewe with lambs, so for 100 ewes with lambs, 0.65sq m x 100 = 65sq m.
- Gates into and through collecting yard should be see-through. This encourages the sheep to move forwards, drawing them towards other sheep and space.
- The boundaries of pens should be solid. This stops sheep getting distracted by other sheep.
What dimensions should the forcing pen be?
The next stage is the forcing pen – the pen immediately before the drafting race. The aim of the forcing pen is to provide an even flow into the race.
Three access gates typically run from this pen: one from the collecting pen, one to the race, and one to the drafting pen.
- It should be big enough to hold 20% of the collected flock, to save time refilling and still allow easy movement of sheep
- Ideally, forcing pens should be semi-circular with three hung gates on a centre post
- Entry angle to the race should be at 30deg if it is funnel-shaped, channelling sheep into the race by being wider at the start and narrowing towards the exit gate
- If your using a circular forcing pen it should be 3.6m in diameter for a 150-ewe flock or 4.88m in diameter for larger flocks
- Boundary fences around the outside of the pen should be at least 1.25m high
- Internal fences should be at least 1m high
Do I need a dosing race?
While dosing can be undertaken in a larger pen, a dedicated dosing race can speed up the job.
Some handling units have two races:
- A narrow drafting race for sorting, 45-50cm wide
- A wider dosing race for treating sheep and checking ewes’ udders, 75-80cm wide
The dosing race can run parallel with a drafting race or a foot-bath, or the dosing race can be located alongside a boundary wall to minimise materials and cost.
The drafting race can be located centrally, potentially allowing sorting on both sides of the drafting race.
- At least one side gate at the rear of the dosing race is recommended to allow treated sheep to exit into a pen
- A 6m x 80cm dosing race holds roughly 16 ewes and a 6m x 50cm race holds nine ewes
- A width of 75-80cm is ideal where a handler works alone inside the dosing race. Any wider and holding sheep and especially young lambs becomes hard
- Allow 0.35sq m for each lowland ewe without lambs
Considerations for the drafting race
A drafting race should be central, easily accessible and long enough to allow “looking time”, which is particularly important when drafting three ways or more.
Ideally, the race should have a concrete floor extending 60cm either side of the race, giving a firm level walkway for handlers.
The aim is to have sheep in single file for sorting.
- A vertical V-shaped race stops sheep and lambs turning around
- Aim for 50cm wide at the top and 28cm wide at the bottom of the V
- A straight sided race should be 45-50cm wide
- Height should be up to 0.85m
- Length should be 6.1-15.25m
- Allow 0.3m for every 10 ewes above 200 ewes, up to a maximum length of 15.25m
- Should be at least 5m from race entrance to encourage sheep into the race
- Drafting gates located along the sides of the race should be at least 1.2m long
- Sorting gate handles should be at least 12cm long
- Handles should be at elbow height
- Having a see-through gate at the end of the race encourages sheep forward
- Aim for three-way sorting with two gates and one person, or four-way sorting with three gates and two people