Some Like It Cool
As the land struggles to recover from its hottest summer for decades, Liz Shankland has advice on protecting your pigs when temperatures soar
What is it with the Brits and the weather? We complain constantly about it, if it’s too wet, too cold, or — as in recent months — too hot. The unusually hot weather began as early as April in some places. Temperatures in June and July, which regularly topped the 30°C mark, were experienced pretty much everywhere and rivalled those recorded during the UK’s longest previous heatwave in 1976.
Following on from one of the coldest, snowiest and most disruptive starts to a year for decades, the Mediterranean-style summer might have seemed like a blessing when it first arrived, but for anyone with land and livestock it quickly turned into yet another battle with the elements. Natural water sources ran dry, crops were scorched and ruined, grassland fires caused chaos and the subsequent shortage of not just good grazing but also hay and bedding straw, left many farmers without vital supplies and increasingly out of pocket as prices rocketed.
As well as having financial implications, the prolonged extreme weather has meant an ongoing struggle for those working hard to keep animals comfortable and healthy. Even if the temperatures cool over the coming weeks, meteorologists are adamant that hot spells like this will occur again, so everyone should be thinking now about ways of coping next time around.
The importance of water
I was fortunate that, when I moved to my second smallholding, I had learned from past experience the importance of maintaining a good water supply to the more remote paddocks.
When I moved into my new place, I hired a team of builders to lay underground pipes from the farmyard and up to the woods and installed a series of automatic drinkers. I invested in a rooftop harvesting system powered by an electric pump which pushed rainwater from collection tanks up to the drinkers but, having farmed through previous droughts, I made sure that there was provision to switch over to mains water as soon as supplies began to run low.
Obviously, all animals need to drink, but with pigs the dangers of dehydration cannot be overemphasised. More than any other species, the pig is acutely affected by water deprivation, which can result in salt poisoning — a very real and potentially deadly condition. The pig’s normal diet contains a small percentage of salt (around 0.4% to 0.6%) but, if insufficient water is available, even this small amount can become toxic and can kill within 48 hours.
The first sign that something is wrong is usually a pig going off its food, so always check if there is sufficient water if a pig does not want to eat. The condition worsens as salt accumulates, leading to clinical symptoms such as staggering and lack of balance, nose-twitching and convulsions. Attempting to rehydrate at this late stage
will sometimes make matters worse, as water is drawn into the brain, causing it to swell. If the signs of water deprivation are recognised early enough, slow, careful rehydration via the rectum may be possible, but this is best attempted by your vet.
Heat stress — often called heat stroke — is another problem of which pig keepers should be aware. All pigs need to stay cool, whether indoors or out. Pigs are pretty poorly designed when it comes controlling their own body temperature; they cannot sweat in the same way other mammals do, only being able to perspire a little from the snout. If pigs are unable to wet their skin, they cannot get cool. A further problem is that pigs actually generate a significant amount of heat: research suggests as much as a 1KW electric fire.
If pigs are kept indoors, good ventilation is essential, while outdoor pigs must have adequate shade and, where possible, mud wallows. Heat stress shares some common symptoms with salt poisoning. Pigs can be lethargic, off their food and they may stagger as if intoxicated. Other signs include: Rapid panting/faster than normal respiration Increased water consumption (up to six times as much) Frequent urination (causing a loss of electrolytes) General discomfort and distress Constant wallowing Trembling Slower pulse rate Diarrhoea (which means a further loss of vital fluids) Some of the effects on breeding stock may not be obvious until a litter is produced — or lost. Oestrus can be disrupted, with sows and gilts having erratic seasons; fertility in both males and females may be poor and quality of boar semen in particular can be affected for several weeks; embryos may be reabsorbed; boars may be lethargic and reluctant to work; in lactating sows, milk supply may reduce or stop completely.
Think about ways in which you can adapt your facilities to make life easier — for your pigs and for yourself. Aside from the serious health risks and discomfort caused by overheating, it should also be remembered that lack of appetite can have a knock-on impact on farrowing rates and growth of pigs being raised for meat.
Liz Shankland is the author of the Haynes Pig Manual and Haynes Smallholding Manual. She teaches courses in pig husbandry and smallholding at Humble by Nature in Monmouthshire (www.humblebynature.com).
Keeping your pigs comfortable and well hydrated is essential
If pigs are unable to wet their skin, they cannot get cool RIGHT This pig is enjoying cooling off in a wallow