When designing pig handling and loading facilities and systems, it is useful to consider the pigs’ basic behavioural characteristics. Incorporating features based on pig behaviour will make it easier to move the pigs with less effort on your part and will be less stressful to the pigs.
Pigs have a wide-angle 310 degree vision, which allows them to see behind themselves without turning their heads. They are easily distracted by objects to the front and to the sides and if they can see a gap, they are likely to try and get through it.
Pigs are distracted by sharp changes in floor texture and appearance. They will baulk at sharp changes in slope and will only proceed if sure-footing is available. They prefer to go up rather than down a slope and are unsure about changes in flooring e.g. going over gaps or hollow-sounding boards covering a drain in a concrete floor.
Pigs will stop or baulk at sudden changes in lighting conditions such as a shaft of sunlight or a shadow across a pathway. Therefore, it is best to keep lighting in loading facilities as uniform as possible.
Pigs have a strong flight reaction and will run when threatened. They prefer to stay in close visual and physical contact with each other and have a tendency to group together when forced.
Pigs are generally cautious of new places and move faster if they have been regularly moved. They have good memories and will remember both good and bad experiences.
Laneways and ramps can be single or double width. Construct them wide enough to accommodate at least two pigs abreast (900 mm to 1000 mm for two baconer pigs; approximately 550 mm for one adult pig) this allows physical contact between the pigs thus working with the social characteristics of pigs moving in a group.
If the laneway narrows, include an offset panel at ramp entrances, rather than a funnel-shaped entrance, to prevent pigs wedging (see Figure 1). A roller on the corner will also assist. Gates along lanes, at the entry to the ramp and part way along the ramp will prevent pigs returning.
Lanes and loading ramps should be constructed of a non-bruise material with no sharp edges or protrusions. The ramp should be easily adjustable to cater for differences in truck height – counterweights or endless chain systems are useful for this purpose. A level platform at the top of the ramp and a solid section to bridge the gap between ramp and truck assists in keeping the pigs moving.
Constructing a catwalk, with a handrail for safety, along the outside of the ramp will allow staff easy access to the pigs on the ramp, which will improve pig movement.
Laneways and ramps.
- Extend the lane horizontally outside the shed for about 3 m before the ramp so that the ramp does not start immediately from the shed.
- Design laneways leading to loading facilities with a gentle curve so that the pigs can see a short distance ahead and will not be distracted by activity further on (relevant for large numbers of pigs and can be the forcing yard).
- Design semicircular forcing yards (approximately 0.32 m squared per baconer pig) with a swinging, solid-panel ‘forcing’ gate, from the laneway to the ramp or into scales, to hold and gradually turn and move individuals from a group of pigs (relevant for large numbers of pigs and assists in weighing facilities).
- Provide weigh scales with solid sides and a see-through exit door to allow the pig to see the way out; a sliding gate with a mesh panel just prior to the scales directs the pig to its next move and reduces its need to turn around and prevents it from interfering with the scales.
- Provide laneways and ramps with solid side panels 1 m high to prevent distraction from pigs, people or objects outside.
- Construct a ramp long enough to ensure the slope of the ramp does not exceed 20 degrees at all ramp heights – a 1-in-3 construction gives 18º. The ramp can be of concrete stairs.
- Install a solid roof or shadecloth over loading ramps and provide lighting to dark areas.
- Use non-slip flooring – a broom finish to concrete is usually sufficient for most laneways leading to handling and loading areas.
- Stamp or coat concrete floors in handling areas and ramps with a non-slip compound.
- For timber-floored ramps, add cleats at least 25 mm high, spaced 200 mm apart to improve traction in slippery conditions. Cleats for smaller pigs need to be closer together to prevent slipping between the cleats and damage to dew claws.
Before moving pigs, first prepare the laneways with gates fixed into position, using solid gates where required. Remove objects including pools of water from laneways before moving pigs.
Use a solid pig board (900 mm x 600 mm with hand-holes) behind a group of pigs. Handling pigs in smaller groups will reduce the potential for jamming and will generally improve the pigs’ flow through loading facilities.
If a group of pigs is jamming, don’t force the pigs at the back but encourage those at the front to move. Try lightly tickling/patting their sensitive backs or use their side vision. Use driving aids such as canvas or cloth flappers (pieces attached to a light rod) and rattles. Do not use sticks or poly piping; do not hit the pigs – good welfare and meat quality as well as efficient moving need to be kept in mind.
To get the pigs used to being moved, a leading behaviour researcher, Temple Grandin recommends ‘walking the pens’: stepping into the pens, getting the pigs standing and just moving so that they flow around you; do not stir them. Grandin suggests that it should take about 15 seconds in a wean-to-finish pen of about 30 pigs, or 50 weaners. Ideally, the pens should be walked every day. Walking the pens is especially useful for pigs that stay in the same pens from weaning to sale. It also helps with meat quality as it can reduce stress at market time and Grandin advises that US processors can tell at slaughter which suppliers walk the pens.
To get the best performance out of your pigs observe good animal welfare practices. When mixing with the pigs, be calm, quiet, nonaggressive and display steady behaviour towards them as this helps to move the pigs smoothly and efficiently. Poor human behaviour in handling pigs negatively influences pig performance and reduces meat quality. Research such as that by Australian Paul Hemsworth and team is summarised in the Prohand training materials, shows that good handling can benefit pig performance and profit by reducing fear and stress, resulting in more pigs being born to each sow per year as well as increased growth rate.
Geoff Pollock; Alison Spencer