An Italian farm became an open-air morgue earlier this month after around 50 cows were poisoned by young sorghum plants, a tragedy experts blame on drought.
The Piedmontese cattle on the farm in Sommariva del Bosco, near Turin in northwest Italy, died suddenly due to acute prussic acid poisoning on Aug. 6, according to the local IZS animal welfare body.
This acid comes from dhurrin, which is naturally present in young sorghum plants, although not in the same high concentrations as those found in samples taken at the site.
"We suspect that the drought caused this very large quantity of dhurrin within the sorghum plants," said Stefano Giantin, a vet at the Istituto Zooprofilattico Sperimentale for northwest Italy, who is on the case.
With normal growing plants, the amount of dhurrin would lower as the plants grew larger. But since the ongoing drought has stunted the growth of sorghum plants, dhurrin has concentrated inside them.
Prussic acid poisoning in cattle is quick and brutal, with symptoms occurring 10-15 minutes after ingestion and death some 15-30 minutes later. It causes respiratory, nervous and muscular disorders.
Dhurrin naturally occurs in sorghum, particularly in young shoots that use it as a defense against herbivores, but when digested, releases prussic acid, also known as hydrogen cyanide.
But "normally, it doesn't cause death," Giantin told Agence France-Presse (AFP).
In the samples taken from Sommariva del Bosco, the concentration of dhurrin in the shoots was at an unusually high level, which Giantin said appeared to be the result of the drought that has hit Italy and much of Europe this summer.
A dose of more than 700 mg/kg of prussic acid is considered fatal for cattle, but the animals at Sommariva were found to have quantities of more than 900 mg/kg in their blood.
The only way of saving affected cows is to inject them with sodium thiosulfate, to neutralize the hyrogen cyanide.
With this, experts were able to save around 30 cows on Aug. 11, when three more farms in Piedmont were hit by the same phenomenon – although not before 14 died.
The head of Italy's Civil Defense has expressed concern over increasingly frequent extreme weather conditions.
"We will continue to have more and more dangerous storms and we should be more attentive," Fabrizio Curcio said, according to a La Repubblica newspaper report Wednesday.
He went on to say that choosing the right approach could make the difference between life and death.
Flooding is common throughout Italy in August and early autumn, however not to this degree, Curcio said.
The pedalos lie far from the water's edge and the flat stone slabs around the Sirmione peninsula are exposed after drought reduced the level of Italy's Lake Garda to a 15-year low.
Italy's largest lake, a major tourist destination nestled among mountains in the north of the country, is suffering like many others from months without rain.
"We are currently at 30 centimeters (12 inches) above the (benchmark) hydrographic level," compared to an average for this time of year of between 80 and 100, said Gianluca Ginepro, head of Garda Unico, which promotes the lake.
It is the lowest since 2007, when levels dropped to 9.9 centimeters, according to official data.
Tourism was holding up well, he said, although operators of trips across the lake had switched from hydrofoils to catamarans.
"The possibility of providing water for agriculture has dropped," Ginepro said.
Farmers have also been hit by a lack of water in the River Po, which stretches across northern Italy and is suffering its worst drought in 70 years.
But the issue goes beyond Italy, with land across Europe parched by a lack of rainfall and sweltering temperatures, driven by climate change. Several other European countries, as well as reporting record temperatures during recent heat waves, have also reported low levels of water in rivers.