CHILLIWACK – The unprecedented heat this summer has producers and consumers alike wondering what life will be like in the future as climate projections anticipate further temperature increases across the province.
The Pacific Climate Impacts Consortium at the University of Victoria says Chilliwack could average as many as 29 days over 30°C each year, up from eight today. This will help boost the average annual temperature in the Fraser Valley by up to 4.3°C by 2050.
Temperatures will not only increase, the range will also grow as temperature extremes become part of the new normal. The eastern Fraser Valley will be among the areas most impacted, with a temperature spread of about 12°C to 15°C, compared to a historical range of around 9°C and 11°C.
Livestock and poultry in the Fraser Valley are especially vulnerable to extreme heat events. The area is home to 50% of the province’s dairy operations and nearly 40% of BC’s poultry and egg producers.
Since the optimal ambient temperature range for dairy production is between 0°C and 20°C, higher temperatures will negatively impact productivity and cattle health. Some adverse effects of heat in animals include higher respiration rates, increased sweating and water consumption, lower feed intake, reduced fertility, lower butterfat content and lower milk production, a BC Agriculture & Food Climate Action Initiative (CAI) report says.
A research team at the University of Wisconsin-Madison found that heat stress can cost farmers upwards of several hundred dollars per cow per year.
The potential impacts of higher temperatures on animal health and productivity are prompting producers to future-proof their barns.
Some approaches include raising the ceiling height to allow for more airflow, investing in larger and more powerful fans, and using evaporative and conductive cooling techniques.
Bill and Jenny Van Reeuwyk of Summershade Farms Ltd. in Abbotsford were prepared for June’s heatwave, but their cattle were still impacted by the heat.
“In the new barn we put up four or five years ago, it’s completely open with huge fans and we’re going to put misters in there after what happened this year,” says Jenny.
The cattle’s milk production dropped and they were less active but the Van Reeuwyks were fortunate to not have lost any animals to the heat.
Indeed, ventilation plays a significant role in keeping cattle cool. Barns with large curtains help maximize air flow and improve the effectiveness of evaporative cooling over the animals, the BC Climate Change and Agriculture Initiatives report says. Natural ventilation, circulation fans and exhaust ventilation are most commonly used in the dairy sector.
“We put up a new barn just a few years ago and built it with very large side curtains. It’s wide open on the sides so the wind can flow right through. That really helps keep the cattle cool,” says Mark Ricka, a dairy producer in Chilliwack. “We have fans placed everywhere in the barn so there are no dead spots of air.”
Ricka also installed fans in each robotic milking room so the cattle always have air moving overhead. His 200 milking cows also fared okay during the heatwave, but feed intake dropped a bit and they stood more than normal.
Enderby dairy farmer Rene Miedema, who has been involved in interpreting the Climate Action Initiative report as a member of the Dairy Industry Research and Education Committee (DIREC), uses natural ventilation and fans to keep his 110 milking cows as comfortable as possible in the summer heat.
In his 12-year-old barn, they installed “large curtains so that we can open up the barn. We are lucky the barn is oriented east to west, so we have a lot of natural air flow,” he says. “Our summers in the Okanagan are fairly warm so we added two 72-inch variable-speed fans. They have made a tremendous difference. Our barn does remarkably well until 35-36°C, which is good, but I don’t think anybody was ready for 40-45°C.”
In addition, evaporative cooling is an effective way to cool cattle in dairy barns. Sprinklers and misters are the most common and effective tools in areas with low humidity.
“We put up a soaker rail. When the cows come up to eat, there are nozzles that point down and spray the cows’ backs while they’re in the feed alley,” Ricka says. “It’s not a mist. It’s more of a soak with a garden hose. It cools them down because they get wet and then the fans move air overhead.”
Conductive cooling is another strategy farmers can use to cool their herds. Waterbeds, for example, can be used under bedding to remove excess heat from cattle. Piping under the bedding area is another option, which circulates cold water.
Radiant barriers and breeding initiatives are other approaches to manage heat.
“We put solar panels on our barn and I noticed the next summer they acted as a radiant barrier. It was a happy accident, because they definitely lowered the temperature in the barn,” Miedema says.
The needs of each operation are unique, and the efficacy of tools will vary from farm to farm. Producers should consider operation size, location and costs of additional equipment required, water consumption and the amount of operation and maintenance that are required to implement each mitigation strategy.
“I think after this heat wave, a lot of farmers will look at misters if they can manage it. We have a lot of tools, I’m just not sure what tools are available to manage over 40°C,” Miedema says.
“Everyone was quite shocked with that heat. When I was walking through the barn, my fans were going full bore and it was like walking through a blast furnace. There is going to be a lot of talking amongst farmers. I will connect with farmers with misters to see how they made out in the heat. That’s the next logical step for me and then after that, I don’t know.”
Fortunately, research is ongoing to gather more information and evaluate the applicability of different technologies in the dairy sector as the effects of a changing climate make themselves felt across the province.