The maimed cattle were discovered in Santa Fe, Argentina and no-one can explain what caused the horrific injuries.
According to local farmers, the animals were mutilated following the appearance of “strange lights” in the sky, which they say were not stars.
Agricultural workers claim the phenomenon was caused by aliens or the legendary ‘chupacabra’ (goat-sucker), a folklore creature which feeds on animals’ blood.
Norberto Bieri, who owns one of the seven cows, said: “They did not have tongues or flesh around the jaw, but they did not take any animals away or remove their bones.”
He added: “It seems as though the clean incisions were done with a laser as there is no trace of a knife being used.
“The cows did not have signs of blood and nothing had appeared to eat them.”
Samples have so far proven inconclusive but confirmed the cows were not poisoned or shocked.
Bieri said: “Some people say chupacabra or aliens did it.
“Others believe it was rodents.
“The truth is, the cows are dead and there are no answers as to why.”
The farmer also claimed that there have been other recent cases of mutilated animals locally.
The Santa Fe cow mutilation match a hugely bizarre series of cases spanning decades in the USA which were featured in a book the 37th Parallel: The Secret Truth Behind America’s UFO Highway – written by Ben Mezrich.
Thousands of mutilated cows and horses, drained of blood and missing surgically-removed organs such as tongues and ears have been discovered along the 37th Parallel, a fixed geographical location based on a point’s distance from the equator, which runs through America.
In the majority of cases, there were reports of unexplained lights before and after the mutilations.
Authorities have looked into the disturbing crimewave and some people have theorised that the horrific acts were carried out by secret military personnel or by satanic cults.
Local media in Argentina said the hocicudos (Oxymycterus), rat-like animals endemic to South America, are responsible for mutilating the livestock.
More than 40,000 Americans have taken out insurance against being abducted by aliens.
They also suggested scavenger birds could also have eaten the cow’s flesh, as they like to feast on the softer parts.
Animal health expert Juan Calla Fontana said animals often die at this time of year “due to exposure and lack of food and therefore there is nothing mysterious here”.
A UFO hunter believes aliens mutilated and killed a herd of cows which died following a devastating storm.
Missouri farmer Jared Blackwelder and his wife, Misty, were devastated to discover 32 of their dairy cows had been obliterated on April 29.