How to manage the farrowing arc or hut

Maintaining the farrowing arc or hut properly is important. This information looks at design, paddock layout and preparations to make during the farrowing period.

Back to Outdoor farrowing environment page

Why is the farrowing arc or hut important?

Defra's code of practice for the welfare of pigs has specific recommendations for pigs kept outdoors, including:

  • Farrowing arcs should be sited on level ground to reduce the risk of overlying. Suitable fenders should be used to prevent very young piglets from straying during the post-farrowing period
  • Farrowing arcs should be insulated and have provision for some degree of extra ventilation, such as manually controlled flaps

Choosing which type of arc or hut to use

There are many different types of farrowing arc/hut designs and the type you choose will depend on budget and personal preference.

Consider the following points when deciding which type to use:

  • Is the sow is able to stand up and lie down comfortably, in terms of length and width?
  • Are the sow and her piglets safe from injury?
  • Is the sow able to make full postural adjustments, including turning around?
  • Will the arc or hut help maintain sow body condition? For instance, insulated huts help maintain a relatively stable internal temperature and, in turn, maintain sow appetite
  • Can the sow and piglets nurse comfortably?
  • Can the sow build a functional nest?

If you have different types of arc on the same unit, measure the performance differences from the various designs and use them to make informed decisions.

It is also a good idea to share the data with other producers and compare performance.

Consider the paddock layout

Make sure arcs are sited on the best land available and consider the following:

  • Ensure the site chosen is the best land available and is free-draining and level
  • Each arc should have a fender that is in working order
  • The direction arcs face should be adjusted according to the season and topography of the site
  • Arcs or fenders should be at least 1.5 m from the fence line, allowing sows enough space to move around without getting an electric shock
  • Reduce draughts by digging in the base of the arcs
  • If used, place curtains on the door fronts before farrowing to help wet piglets stay warm
  • Ensure all vents or flaps are working as draughts cause piglets to lie in unfavourable areas, increasing the likelihood of crushing
  • Ideally, sows and gilts should be placed in single farrowing paddocks for ease of management
  • Individual farrowing paddocks should be 20 m² and weed-free
  • Drinkers and troughs should be no more than 10 m from arcs and avoid electric fence lines

Preparing the arc or hut

Providing the correct environment for both sows and piglets in the farrowing arc will help to minimise mortality, maximise piglet growth rate and maintain the sow in good condition ready for the next cycle.

A well-prepared and organised farrowing paddock will make your role easier and more productive.

After weaning

  • Move the arc to a fresh piece of ground within the farrowing paddock and remove bedding from the paddock
  • Weather permitting, leave the arc upside down so that the inside is exposed to sunlight
  • If appropriate, wash and disinfect the arc
  • Repair any broken or damaged areas of the arc

Before moving sows in

  • Remove large stones from inside the arc and check it is situated on a fresh piece of ground
  • Place wads of dry wheat straw (or chopped barley straw) in the hut. You will save time by placing the wads on the ground of the intended arc site before you tip the arc over
  • Dig in any ruts under the arc to reduce draughts. This involves spreading soil over the gaps between the ground and the arc
  • Place the fender near to the arc, unless drop-front fenders are used, in which case these can be attached and the front dropped
  • Check the back vent to ensure that it is still in place after moving the arc and adjust according to the weather
  • Double-check the water provision and fence lines before the sows are moved into the farrowing paddocks
  • If there is variation between the size of arcs, try to allocate gilts and smaller sows to the smaller arcs

Before farrowing

  • Check the back vent and adjust according to weather conditions
  • Check the bed prior to the expected farrowing date to see if any additional straw is needed, especially if strawing up is unlikely to occur at weekends
  • Provide wheat straw for nest building. Barley straw should be avoided as the stems are long and stalky and can get wrapped around the piglets
  • Providing too much straw too quickly can cause problems. Young piglets will not have the strength to push through large amounts of straw to reach the teats. They could also get stuck underneath which puts them greater risk of being laid on by the sow
  • Flatten out the straw if the bed is uneven
  • Check again for draughts; fill any holes with straw or cover with soil
  • Check when to attach the fender and any door curtains with your line manager
  • If the fenders do not fit properly, use cable ties to ensure there is a flush fit between them and the arc


First 48 hours

  • Leave the bedding alone. Any disruption of the bed/nest can break the feeding pattern
  • Consider the amount of liquid produced during farrowing and its contribution to dampening the straw
  • If there is a step in and out of the arc, place some straw in the fender area to make a temporary ramp. This will help piglets climb back in if they fall out of the arc

First two weeks

If you check piglets/beds while the sow is feeding, remember that the piglets’ greatest heat source has just left the arc. The amount of time sows spend in the arc determines how much straw is needed.

Sows that spend a long time out of the arc will not be providing heat to the piglets, so more straw will be needed for warmth. Sows that only leave the arc to feed and drink will need less straw, as piglets will gain heat from the sow for most of the day.

  • Try to keep the spread of farrowing to a minimum within the same row of individual paddocks, e.g. seven days maximum. This will make feeding and weaning easier
  • At weaning, remove and reposition arcs, keeping them in neat, straight lines
  • Remove soiled bedding and place farrowing arcs onto a fresh part of the paddock between every farrowing
  • Piglets need to be kept clean, dry, warm, well-bedded, draught-free and experience minimal temperature fluctuations
  • A fostering box is an important tool and must be easily cleaned and disinfected after each use
  • General appearance and tidiness of the unit is very important. On-farm conditions reflect the standards shown from landlords of arable land in terms of hygiene, tidiness and enthusiasm.

Useful links