It would be “kinder to shoot” the hundreds of thousands of unwanted male dairy calves due to be born in Ireland this year, rather than export them to the Middle East or let them die on the farm, experts have told the Guardian.

Irish farmers have hit a streak of gold on dairy exports, and as a result the industry has rapidly expanded, with the national dairy herd rising from about 1m in 2010 to 1.6m this year.

But that creates a whole new problem. Dairy cows generally give birth every year in order to maintain their milk output. But male dairy calves are no use to the farmer as they cannot produce milk, which means that Ireland will need to deal with as many as 800,000 unwanted male calves this year, in what has been described by the Irish agricultural press as a “calf tsunami”.

Q&A Why are we reporting on live exports? Show Hide This week the Guardian’s Animals Farmed series is focusing on the global live animal export trade, which, despite welfare and disease concerns, has quadrupled over the last fifty years. Nearly 2 billion animals a year are loaded onto trucks or ships and sent off to new countries on journeys that can take weeks. Every day at least 5 million creatures are in transit, in a secretive global trade in live farm animals. And those numbers are just the cross-border journeys. They do not include long journeys within countries, which are becoming more frequent due to a trend that has seen smaller slaughterhouses close down. We’re taking a moment to focus on some of the implications of this global trade.

The situation is further complicated by Ireland’s “compact calving” system, which sees most calves born in a 12-week period from February to April, and the swift removal of calves from their mothers. Both increase the need for extra short-term labour, which can be costly or hard to find.

The Irish beef trade has formerly been a useful outlet for unwanted dairy calves, but demand last year was sluggish, and selective breeding increasingly means that dairy calves may not be suitable for beef anyway.

Exporting the calves is another option. Although campaigners are opposed to the trade, the Irish government has described it as “a vital safety valve for the beef sector”.

The only alternative is to shoot the calf at birth, or to let calves die of neglect. In 2015–16 New Zealand, another country with a large dairy industry, was hit by the male calf scandal when videos and reports of starved and abused male dairy calves were widely circulated by welfare organisations.

“The danger of having so many calves in 2020, on top of the existing pressures, means there is an emergency welfare case to be made, although no one wants to talk about it, for killing the calves on a one-off basis at three or four days old,” said a senior figure in Ireland’s state agricultural network. The source spoke to the Guardian on condition of anonymity for fear they might lose their job.

“We know there is going to be suffering. We know the farmers can’t manage and we need to offer a realistic solution to ease that suffering, for the calves and the farmers,” the source said.

“Vets often say they are only called to treat female calves. The whole reason New Zealand is in the situation of killing calves at four days old is because they had the same problems with valueless male dairy calves about four years ago.

“Vets are not called to sick pigs [in Ireland],” the source added. “And this is the way we are going with male calves.” Calves and pigs are worth significantly less than the cost of a vet, so it can be cheaper to simply let them die.

Difficult as the decision is, the source said it was preferable to letting them “die in their own scour [diarrhoea], which is what is happening now and we know is going to get worse”.

Although most dairy industry professionals refused to openly discuss the possibility of a cull, Cork based cattle vet Bill Cashman spoke on the record. “When a male calf has no value, or is a net cost, with the best will in the world a farmer, especially when under intense day and night work [pressure], will prioritise female calf care over the bulls.”

Although Cashman said it was a “wanton waste” to kill any animal at birth, the immediate priority was to ensure that “males are not suffering from a lack of care and disease” or spreading those diseases, and “that means a cull at one or two days old. I would not leave them longer.”

Asked how a cull might work, Cashman said, in line with the Federation of Veterinarians of Europe policy, he would prefer to see it happen on the farm, to avoid transport, by lethal injection. “It’s instantaneous. A visit could be made every second day [during calving season.]”

The option of exporting the calves may provide a financial return for farmers, but campaigners have queried the welfare implications of sending young, unweaned calves on long journeys by ship or truck. The minimum age is supposed to be 14 days, but the same source told the Guardian that it looks as if some farmers are registering calves as born earlier, in an attempt to get them off the farm as quickly as possible.

European veal farms are the main export destination for younger calves, while older animals – male and female – tend to sell to Turkey, Libya, Morocco, Lebanon, Russia, Tunisia, Rwanda or Kosovo for beef and dairy use.

Mistreatment has been well documented. In a 2018 report on farm animal welfare the European Court of Auditors noted Ireland was guilty of infringing calf transport rules. A 2016 investigation by Compassion in World Farming showed that some journeys were lasting over 27 hours, in cramped conditions with no drinking facilities. In May 2019footage taken at a at a French control post appeared in Cherbourg by animal activist group Eyes on Animals appeared to show calf mistreatment.

There is also concern about slaughter conditions in non-EU countries.

But the Irish government has repeatedly pledged its support for the export sector and has encouraged companies to form their own representative organisation. In January 2017, Ireland’s minister for the Department of Agriculture, Food and the Marine (DAFM), Michael Creed, reportedly told the Irish Farmers’ Association annual meeting that the live export trade was “critically important”.

There has been a rise in the number of cattle exported over recent years although the value of industry for livestock – at about €110m (£94m) a year – has declined 6% year-on-year.

“It is not boosting the economy,” Caroline Rowley, from Compassion in World Farming, said. “It is not stimulating prices, live export volumes are going up each year but factory prices are not following. It is not helping the average livestock farmer. The only winners in this outdated industry are the exporters.”

Colorado-based animal science expert Dr Mary Temple Grandin told the Guardian that from a welfare perspective slaughtering very young calves is likely more humane than a long journey by sea without milk replacer. The drawback, she said, was a potential food waste issue. Asked what happens to their slaughtered calves, New Zealand’s Ministry for Primary Industries said in an email they are “typically processed for pet food”, which goes some way towards addressing Grandin’s waste concerns.

Although no farmer would endorse the idea of an emergency calf cull on the record, there was agreement on individual calf neglect issues. Denis Drennan is a dairy farmer and committee chairman with the Irish Creamery Milk Supplier Association. Drennan, who has 60 dairy cows, summed up the reaction of many farmers to the idea of a cull, saying if he was shooting animals at birth, he was not a farmer.

Asked if male calves are sometimes left to die, or whether there are farmers who only call a vet for a female calf, Drennan said yes.

Where a vet might cost about €150 at night, domestic prices for calves, which can earn farmers anything from €30 to €80 per head at auction, reportedly fell as low as €0.50 per head last year. Live exporters, meanwhile, estimate their 2020 prices would stay in the €30 to €60 range.

Replying to questions about a potential emergency calf cull Ireland’s DAFM said by email that it “continues to engage with and work closely with stakeholders in relation to the incremental increase in the number of calves born on the dairy farms over the past few years, with a focus on rearing, management and market opportunities for such calves, including opportunities for intra-community trade to other EU member states.” The department’s statement went on to say that “in addition to its direct oversight of animals presented for export”, it will “continue its range of inspections and controls on farms and at sales to monitor compliance with animal welfare standards”.

One result of that engagement appears to be a December DAFM announcement that Irish government veterinary inspectors “will accompany calves from Ireland to the control posts in Cherbourg”, without prior warning. It said too that rubber teat water drinkers will be mandatory for unweaned calves from 1 December 2020.

Reacting to the new rules, Eyes on Animals’ Nicola Glen said she was pleased to see the “serious welfare issues associated with the transport of Irish calves” were finally receiving proper attention. However, she said it was unclear how the vet checks would work in practice and that although the new rubber teat rule was an improvement on the existing system of hard-to-access metal pipes, December 2020 was too far away. Eyes on Animals will continue its inspections until it sees concrete results, she added.