30/12/2012 11:40 GMT | Updated 28/02/2013 05:12 GMT

Are Vegetarians Fooling Themselves? A Case For the Vegan Option Continued

There are several types of vegetarian. Lacto-vegetarians eat dairy products but not eggs. Ovo-vegetarians eat eggs but not dairy products. Ovo-lacto-vegetarians eat eggs and dairy. But vegetarians who have chosen to forego meat in order to avoid the killing of animals may find that they are - albeit unwittingly - complicit in just that.

Since the overwhelming majority of farm animals are factory farmed (95% in the UK and Canada, 99% in the US) it is likely that their eggs and dairy products are sourced from the intensive agri-industries. These systems are designed to suit the industry and as a result the needs of the animals are disregarded.

Take eggs. Hens in the commercial sector are bred for high egg output. Being no good for meat male chicks are an unwanted by product. Thrown alive into grinding machines or into bins for gassing with carbon dioxide, their remains are used for animal food or fertilizer.

Even hens selected for the organic and free-range egg market are sorted this way. Although these birds have the freedom to exercise, have litter for dust- bathing and areas for nesting, they are kept in large colonies - up to 3,000 in the organic sector and 4,000 in the non-organic free-range sector. With flocks too large for birds to form a natural pecking order they often, in their stress, turn on each other. In order to avoid 'cannibalism' (which can cause 25-30% mortality) farmers - even organic farmers, though only with special permission - resort to beak trimming, a hugely painful and disabling mutilation.

When egg production begins to fall off - usually after about one year of laying - hens are taken to slaughter. Their carcases are used for cheap food products like soups, pastes or stock cubes, or processed into fertilizer. This is intensive production. A healthy free-range chicken can live for 15 years.

Then there is intensive cows' milk production. In the UK this accounts for 95% of all cows' milk production, including organic. To ensure a constant supply of milk cows calve once a year. Those with no commercial value are killed at birth. Those to be kept as dairy herd replacements or destined for the veal and beef markets are removed from their mothers within a few days of being born.

Meanwhile dairy cows, having been treated as little more than milk machines, will be culled after two to five years of milking (depending on the intensity of the system) and their carcases processed into cheap food products like soups, pastes and pâté.

Goat milk production is also becoming more intensive. 'Zero grazing' is becoming more common (as it is for dairy cows) which means that animals spend all their lives inside. As in the dairy cow industry mothers and offspring are separated at birth. And, like dairy cows, female goats, worn out by excessive milking, might be culled after only a few years of milking and sold as meat. A goat's natural lifespan is between 15 and 20 years, a cow's 17 to 20.

And what of sheep's milk products: cheeses like Feta, Halloumi and Roquefort? Dairy ewes are worn out more quickly than ewes that are farmed only for lambs. 'Spoiled udders' (a trade euphemism for mastitis) are a common cause of culling. 10 - 12 years is a sheep's natural lifespan, a dairy ewe's five to seven.

When labels read "Suitable for vegetarians" it might be more appropriate if they came with a warning: "Suitable for vegetarians ??". For if eggs or dairy produce have originated from factory farms then buyers are complicit in supporting the intensive egg and meat industries that involve slaughter and cruelty on a massive scale.

Only at small retailers, farm shops and farmers' markets can customers find out if the food they buy has a compassionate provenance. The extra expense means that animals will not have suffered the cruelty inherent in the factory farming system, reared with such brutal efficiency that their entire lives are, in effect, torture.

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