In the paper, Séralini examines the raw data from pathology reports of dairy cows belonging to German farmer Gottfried Glöckner, co-author of the paper.

Between 1997 and 2002 Glöckner fed his herd feed containing up to 40% GM maize, and saw the proportion of healthy cows with a high milk yield fall from 70% - a normal rate – to 40% with a peak mortality rate of 10%. Around 30% of his herd was unhealthy, the farmer said.

The study says: “The GM maize, subsequently withdrawn from the market, was at the time the only intended managerial change for the cows. It is proposed that it provoked long-term toxic effects on mammals, which are typically not observed in the usual high-turnover (more rapid than 3 years) conditions of intensive farming.”​

Disappearing act​

The paper, entitled “Pathology reports on the first cows fed with Bt176 maize (1997–2002)” ​was published in the journal Scholarly Journal of Agricultural Sciences (SJAS). ​It had been presented at a press conference organised by the Committee for Independent Research and Information on Genetic Engineering (CRIIGEN) on Tuesday 26 January in Brussels, and was available online​.​

But this link now redirects to page which states the domain name expired on Wednesday 27 January.

When asked by FoodNavigator if he was aware the domain would expire, Gottfried Glöckner sent an email response, also received by website Retraction Watch: “​We did not know why!?”​

The Scholarly Journal of Agricultural Sciences ​appears on a list​​ of “potential, possible, or probable predatory scholarly open-access publishers,”​ compiled by Scholarly Open Access which describes itself as providing critical analysis of open access publishers.

Cadherins and toxicity​

Symptoms included long-lasting paresis syndrome – without infection or fever –, kidney biochemical failure, some liver toxicity, some muscosal problems and, in the most serious case, a break on the mammary gland.

In the study, which can be consulted on the GM Watch website​​, Séralini details how Glöckner carried out examinations in collaboration with the German ministry of Health, university laboratories and Syngenta (then Novartis), for bacterial and viral infections, as well as parasites and mycotoxins but none were found. “The deaths were not linked to infectious or genetic diseases,” ​writes Séralini.

Séralini writes: “As a possible scientific explanation for these pathologies, it is known that the cadherin family of transmembrane proteins play an essential role in the bovine kidney as well as during gestation and in epithelial cells. It was recently discovered that some cadherins are involved in the mechanism of toxicity for Cry1Ab the toxin produced by this GM Bt maize,” ​write the authors.

“This hypothesis may explain some symptoms at the level of the kidneys and mucosa or epithelia. This does not exclude other possibilities, such as the presence of new toxic metabolites in the GM maize.”​

They call for more long-term feeding trials to be performed before other market releases of GM Bt-producing plants, as well as Roundup-tolerant GMOs.

The paper also says that, during the initial two-week trial period when the GM Bt maize was developed by then-Novartis one cow died due to electrolyte and muscosal problems. “This information was not public at the time, but one of the authors of this article (Gilles-Eric Séralini) had access to the file as an expert on GMOs for the French government.”​

The pathology reports were made available to Séralini following the end of a court dispute between the farmer and Syngenta in which Glöckner sued the company for losses. He was awarded partial compensation.

The Séralini saga: Retractions and republications​

Professor Séralini and his lab came to prominence after previous research published in 2012 linking the consumption of Monsanto's NK603 GM maize and its associated herbicide Roundup to long term toxicity and cancer in rats​​, gaining huge media attention in part due to photographs of the tumour-ridden rats.

But amid heavy criticism​​ from many in the scientific community, and rejections of the study by several high profile regulators including EFSA​​ and the editors of the Food and Chemical Toxicology​ (FCT) journal where the study had initially been published, eventually leading to its retraction. Séralini claimed the decision was based on 'unscientific double standards'​​ and the paper was later republished in Environmental Sciences Europe​​.