Why heat hits pigs harder than most stock
A pig in a heatwave is an animal whose main cooling system never arrived. Pigs have very few working sweat glands, so the route horses and people rely on — evaporation off damp skin — barely exists for them. A hot pig's options are behavioral: find shade, find water or mud, stretch out on cool ground and pant. When the weather removes those options, body temperature climbs with nothing to check it, and pigs can move from uncomfortable to in trouble faster than most keepers expect. That is why heatwave provision for pigs is not enrichment or kindness on top of normal care; the shade and the wallow are the cooling equipment, and they need to be in place before the hot spell, not improvised during it.
Shade that moves air, not just shade that blocks sun
The test of a pig shade is not the darkness of the shadow but the air inside it. A roof on open sides — a field shelter with the ends open, a tarp rigged high, a purpose-built shade over a hard standing — lets every breeze pass through at pig height, carrying heat away. A low, enclosed hut that happens to be dark can be hotter inside than the field outside it. Size the shade for the whole group lying flat at once, with room to spare: pigs that have to pile together to fit under the cover are heating each other, and the lowest-ranking pig, pushed out to the sunny edge, is the one the heatwave will find first. Site the shade on ground that drains, because the most popular corner of a pig paddock turns to soup quickly, and check that the shadow actually covers the pigs at midday, when the sun is highest and shadows are shortest — morning shade that wanders off the pigs by noon is a decoration.
The wallow: shallow, muddy and in the shade
Dig the wallow where the shade already is, or shade where the wallow is; a wallow in full sun becomes a warm bath that pigs avoid. It needs to be shallow — a broad, dished hollow rather than a pit, deep enough in the middle for a pig to submerge its belly and sides, with sloping edges every animal can walk in and out of, including the smallest. Fill it and keep it filled: in a heatwave the wallow loses water to evaporation and to every pig that climbs out wearing a coat of it, so topping up is a daily job, sometimes twice daily. The mud is the mechanism. Pigs plaster themselves deliberately, and as the water in that mud evaporates it draws heat from the skin — the pig wearing its own swamp cooler. Keep the wallow away from the feeder so it stays a bath rather than a dining area, and expect the ground around it to need the same drainage thinking as the shade.
Heatwave watch: the signs and the threshold for the vet
During a hot spell, look at the pigs at midday rather than only at feeding times, when even a struggling pig may rouse itself. Early signs are panting that does not settle in the shade, restlessness, pigs spreading out and lying apart, and feed left untouched. Move a pig showing those signs into the shade and the wallow, offer cool drinking water, and wet it down gradually with cool — not icy — water while you watch. A pig that is staggering, breathing with its mouth open and tongue out, or too weak to rise is an emergency: keep cooling it gently, stop any handling that stresses it further, and call the vet at once rather than waiting for the evening to bring relief. Build the watching into the day's jobs so it cannot be forgotten in a busy week: with KinsLe Care Teams, the midday heat check and the wallow top-up can run as set duties for the duration of the hot spell, each timestamped as it is done.