This photo by the Humane Society of the United States shows gestation crates in use at a Smithfield Foods pig breeding facility in Waverly, Virginia, in 2010.
Efforts to phase out the use of cages in food production are gaining momentum in Europe, challenging farmers and veterinarians to adapt to non-cage systems that can bring animal welfare risks of their own.
The European parliament has "tentatively scheduled" for early June a communication that will spell out its formal response to a petition calling for an end to various forms of farm-animal confinement, including cages for laying hens and farrowing crates for pigs giving birth.
The petition, signed by about 1.4 million people across 18 member countries, was received warmly this month by officials, including the European Union's agriculture commissioner, Janusz Wojciechowski.
"Whatever changes [that] will be ultimately decided will have to provide for appropriate transition periods, which give sufficient time to farmers to adapt, but also incentives to change," Wojciechowski said on Twitter.
Given that the EU is one of the world's largest and most powerful trading blocs, any rule changes there could have repercussions for trading partners globally. "We need to make sure that imported animal products have been produced according to the same animal welfare standards applied by EU farmers and accepted by our citizens," Wojciechowski said.
The extent to which cages can be used in food production varies dramatically around the world. In the United States, for three common means of containment — battery cages for laying hens, gestation crates for sows and veal crates for calves — 13 states have banned one or all of those methods, according to the American Society for the Prevention of Cruelty to Animals.
Farming practices in Europe also differ markedly among member states, with some, such as Austria and Luxembourg, having almost completely eradicated the use of cages, while others, such as Spain and Portugal, still use them frequently. (The "End the Cage Age" campaign, which organized the petition, has created a league table that compares the percentages of cage-free farmed animals among EU member states.)
For laying hens, the European Union in 2012 banned the use of battery cages — so called for their arrangement in connected identical or similar units — but farmers may use "furnished" cages, which are larger and typically include perches and nests. Lawmakers in Europe are now considering whether to prohibit furnished cages, too, effectively mandating non-cage farming for laying hens. Some countries, such as Austria, Germany and Switzerland, already have banned all cage systems for laying hens.
The use of gestation crates — tiny metal enclosures used to house individual pregnant pigs — is banned in the EU except during the first four weeks of pregnancy. The use of farrowing crates during birth also is permitted. Recommendations being considered in Europe include shrinking the maximum amount of time that sows can spend in gestation crates to four or five days, down from the current maximum of 24 days, among other changes that would let pigs roam more freely.
Benefits and pitfalls of cages
Veterinarians are playing a large part in deliberations. As part of this month's parliamentary discussion, lawmakers were presented with a report prepared by a team from Utrecht University's veterinary school in the Netherlands. The report, commissioned by the EU's Policy Department for Citizens' Rights and Constitutional Affairs, outlines alternatives to cage housing and their respective impacts on animal welfare. It mostly focuses on laying hens and sows, which account for a large proportion of caged animals in Europe and offer the greatest scope for change.
Caging hens is considered cruel because limited movement can cause bone problems such as osteoporosis. Being caged also prevents birds from foraging and dust-bathing — important behaviors that are hardwired in their brains.
Cages aren't all bad, however. Furnished cage systems perform better than non-cage systems with regard to mortality rates, parasitic disease, bone fractures during laying, feather pecking, cannibalism and crowding, according to the report.
Outdoor non-cage systems, otherwise known as free-range, have a lower risk of feather pecking and cannibalism compared with indoor non-cage systems, it said. However, the risk of parasitic disease and predation by birds of prey is higher outdoors.
"Even if you don't keep the animals in pens, that doesn't mean all of a sudden it's perfect," Dr. Ellen Meijer, one of three veterinarians who contributed to the report, told the VIN News Service. "Being able to keep animals in unconfined systems is a different skill. So for vets, it presents a different way of working and a different way of supporting the farmer, in training and in early detection of problems as they arise."
For laying hens, possible risk mitigation strategies in non-cage systems include separating hens into subcompartments and blocking off corners to prevent overcrowding and smothering. Perches shouldn't be set too high, the report suggests, to decrease the risk of keel-bone damage when hens jump down.
In free-range systems, hens should regularly be treated with parasiticides. Providing natural cover in the form of trees and shrubs can help reduce the risk of avian influenza and other diseases being introduced by wild birds, according to previous research referenced in the report.
The authors also cite innovative concepts in cage farming, such as the Rondeel and Kipster systems used in the Netherlands, which combine a large indoor foraging area with a smaller "verandah" on the outside to provide natural light and fresh air. The verandah is protected from above by over-head netting. Inside, additional foraging opportunities are offered to make the area more enticing to hens, such as alfalfa hay racks, straw bales, pecking blocks, sandboxes and platforms.
Safeguarding piglets a challenge
In giving pigs more space, the risks can be equally as complicated. Sows, which are naturally competitive, often are kept individually in cages around insemination and during piglet nursing. Removing them from snug cages ups the risk of them harming one another, farmers and their own piglets, according to the report.
When they're set free, risk mitigation can include putting sows from the same insemination group in "mixing pens" beforehand so they can get to know each other, with sufficient space for rank fighting — or avoidance of fighting — to prevent injuries, the report suggests. Electronic feeding systems might be used to alleviate the risk of weaker sows going hungry due to competition over food.
To stop piglets from being crushed, in the absence of farrowing crates, pens might be fitted with sloped walls, rails and bars. Sensor systems could even be used to predict the timing of farrowing and provide caretakers with an alert that a sow should be restrained.
"Well-designed pig pens have their own functional areas, so the pigs know where to eat, defecate, play and rest," Dr. Tijs Tobias, another veterinarian who worked on the report, told VIN News. "If pigs don't know where to eat and sleep, they may show undesirable behavior like aggression."
One obvious impediment to implementing more humane farming systems is their financial cost, Tobias said: "This is, of course, the big elephant in the room."
Tobias, Meijer and their seven co-authors acknowledge that wholesale bans across Europe could take years to accomplish. In the interim, they suggest that subsidies or conditional loans could help farmers ready to make a shift. Clear and reliable labeling of products regarding welfare aspects, meanwhile, could help consumers and retailers make informed choices.
"Often, society at large would like to have better welfare, but the consumer doesn't always want to pay for it," Tobias said. "Regulators might want to apply a new bottom, or minimum welfare standard, and slowly increase that level so you can reach non-cage housing in the end."
Meijer believes an already evident willingness by consumers in some countries to pay more for free-range eggs provides reason for optimism. "In eggs, we've seen that it's slowly evolving," she said. "While it takes time, producers and consumers can get used to the cost and set their standards that little bit higher."
VIN News Service commentaries are opinion pieces presenting insights, personal experiences and/or perspectives on topical issues by members of the veterinary community. To submit a commentary for consideration, email email@example.com.