Saskatchewan's Ministry of Agriculture estimates that farmers are facing a loss of $300,000 after the death of more than 200 cattle in a grazing pasture north of Shamrock, Sask.

The deaths have sparked a widespread investigation by the ministry, animal protection officers and veterinarians.

At a news conference in Regina on Monday, Chief Veterinary Officer Betty Althouse said the ministry is currently waiting for post-mortem test results from the Western College of Veterinary Medicine at the University of Saskatchewan, which should be back by the end of the week.

The water tests are expected to come in Tuesday, but Althouse said it was likely dehydration that killed the cattle due to concentrated salt in the water.

Extreme heat, water supply issues

Water evaporation during hot weather can lead to a salt content that is higher than the ocean, Althouse explained. Consuming water with that much salt can lead to death in humans and animals, including cattle. 

The cattle were found dead in pasture operated by Shamrock Grazing Ltd., a company that leases Crown land from the province and charges ranchers several hundred dollars per head to oversee grazing and water access over the summer. It hired a new pasture manager earlier this year.

Betty Althouse at cattle scrum in Regina

Chief Veterinary Officer Betty Althouse said the cattle were likely killed by dehydration, although officials are still awaiting test results. (CBC)

According to local ranchers, about 680 head of cattle were moved to a new plot of land on July 1, then checked on July 2. The dead cattle were discovered five days later.

The RCMP detachment in Gravelbourg, Sask., responded to the scene after receiving a complaint.

Shamrock Grazing Ltd. president Glenn Straub told CBC News the pasture and water supply had been used before. He would not comment on the possible cause of death prior to the release of test results. 

Althouse said the incident is a reminder that water sources can change over time depending on run-off and heat.

"I think the important message here is that you do need to test the water. Make sure animals do have access to fresh water, that the water source being used is tested on a regular basis, especially if conditions change."

Both cows and calves were among the 200 head of cattle that died. Another 240 were moved to new pasture after the deaths. Althouse said that herd is under veterinary care, with shade, fresh water and required medical treatments.

'Make sure animals do have access to fresh water, that the water source being used is tested on a regular basis, especially if conditions change.' - Betty Althouse, chief veterinary officer

Weaker cattle are being brought back onto water slowly; some are on an IV solution and others are being given electrolytes.  

"Usually as long as water is provided not too quickly, slowly the animals will recover over time," Althouse said.

Farmers facing huge financial loss

Some areas of Saskatchewan are more prone to higher-than-average salt content in water, according to Althouse, but salt poisoning could happen anywhere. The ministry hasn't yet seen a similar case this year, and Althouse said it's the most deadly case she's heard of in the province.

A total of 30 producers owned cattle on the property, but between six and 10 owners were affected by the deaths. The ministry estimates that those farmers are collectively facing $300,000 in financial loss.

"It's very difficult," Straub said. "It's not always the financial part. To these cattlemen, it's almost like losing their family."

CBC News spoke to several ranchers who lost cattle. They describe a disturbing scene of rotting carcasses littering the pasture and floating in the dugout.

They suspected that the deaths were due to extremely high temperatures and a problem with the fresh water supply.

"It's heat and certainly some human error," said rancher Russ Coward, who had cattle that died.

Coward said his primary concern now is to help the animals that are still weak, as well as calves that were orphaned.

"We don't believe anyone was malicious, and we just hope there are some lessons that can be learned from this."

Deaths being investigated

Some live animals have also been transported to the university for testing.

The RCMP say they are assisting animal protection services. No charges have yet been laid.

The cattlemen didn't know what kind of insurance or compensation may be available to them to cover their losses.

The land was previously operated by the Prairie Farm Rehabilitation Administration, until it was privatized.

Ministry staff are advising the company on safe burial practices, and Althouse said there are no concerns of disease at this point.

Shamrock is located 80 kilometres southwest of Moose Jaw, Sask.