Every year in Australia more than 320 million chickens are raised and killed for their meat, these are known as broilers. The vast majority of chicken meat comes from chickens raised in crowded sheds. These sheds house 10,000-20,000 birds at one time.

Describing a broiler shed, The Poultry Digest 1998 quotes from the findings of a Melbourne University report "to enter a chicken shed is to enter an atmosphere full of contaminants: dust, gases, micro-organisms, chemicals".

Accelerated growth of birds

Broilers only live for about eight weeks before being processed for human consumption. At the turn of the century it took a broiler 96 days to grow to slaughter weight (about two kilograms), today it takes 37 days as a result of selective breeding for quick meat growth.

Selective breeding and the addition of growth stimulants to feed, results in baby birds which have the bodies of adults. The March 2000 report on broiler welfare by the European Scientific Committee on Animal Health and Animal Welfare (SCAHAW) concluded "most of the welfare issues that relate specifically to commercial broiler production are a direct consequence of genetic selection for faster and more efficient production of chicken meat and associated changes in biology and behaviour".

Such accelerated growth rates of birds cause problems to chickens. The anatomical characteristics of their gait have altered causing leg and joint problems. In some cases the legs cannot support body weight leaving chickens to starve or dehydrate, as they are unable to support themselves and cannot access the automated feed and water systems found in the sheds.

Health issues

During the seven-week growing period, chicken droppings accumulate on the litter (straw, ricehulls, sawdust or wood shavings) which covers the shed floor resulting in wet litter with a high nitrogen content. Because of the pain in their legs many birds squat down on the floor, the result can be hock burns and breast blisters. The previously mentioned SCAHAW report cited scientific evidence which showed that lame broilers spend up to 86 percent of their time lying down.

Exaggerated growth rate can also cause heart failure and the build up of ammonia and dust in the sheds can cause respiratory problems. In 1998 the Federal Department of Primary Industries said respiratory disease was one of the major causes of broiler deaths.

Cambridge University professor Donald Broom described the modern day broiler hen as "rather like a child who is nine-years-old in weight having to stand on the legs of, say, a five-year-old". Indeed broilers reach slaughter weight within about 40 days of being hatched, whereas non-broiler chicks do not reach adulthood until about five or six months after hatching.

Birds in severe pain, unable to support the weight of their body

The faster a bird grows the higher the incidence of leg problems. Endemic studies have shown that 90 percent of birds have a detectable abnormality in their gait. Pathological leg conditions which have been found in broilers include: tibial dyschondroplasia, twisted leg, tibia septic arthritis in joints, "kinky back" and slipped tendons Ð all of these leading Nairn and Watson in a 1972 study on broilers to conclude "we consider that birds might have been bred to grow so fast that they are on the verge of structural collapse".

Abnormal heart failure

Though they only live a few weeks, broilers suffer old-age illnesses such as heart attacks, as their hearts and lungs are unable to keep up with the fast growth of their body muscle. Heart attacks and the so-called acute death syndrome are major causes of mortality. Heart failure is directly related to the exaggerated growth of chickens. The strain on their cardiovascular system is enormous, the congestive heart failure which causes ascites Ð a pooling of blood fluids in the abdomen. The SCAHAW report states ascites affects nearly five percent of broilers worldwide. The high oxygen demand of rapid growth in the modern broiler combined with restricted space for blood flow through the capillaries of the lung results in an internal accumulation of yellow or blood-stained fluid. Compared to other chickens, heart related mortalities have only been observed in broilers. Cardiac arrhythmias have been found in broiler chickens as young as seven days of age.

Transport and slaughter

As the birds grow their condition worsens and they become less mobile, unable to reach the waterers and feeders, up to two percent of broilers are killed prior to slaughter due to leg and joint problems. In an article in The Guardian (14/10/1991) Professor John Webster of Bristol UniversityÕs veterinary school said: "Broilers are the only livestock that are in chronic pain for the last 20 percent of their lives. They donÕt move around not because they are overstocked but because it hurts their joints so much."

Before slaughter the broiler must endure capture and transportation. Catchers walk through the sheds at night grabbing birds by one leg and carrying them in bunches (up to five chickens in one hand) to crates. These crates are then stacked onto trucks.

In transit the broiler, who has spent its life in a darkened shed, is exposed to light and traffic noise, some died during transport a result of the rough handling or heat stroke.

At the slaughterhouse chickens are shackled to a conveyor belt which carries them along the processing line. The line passes across an electrified water bath, which is intended to stun the birds before an automatic knife cuts their throats, birds then proceed into a scalding tank, to loosen their feathers before plucking. Unfortunately some birds lift their heads and miss the electrified water bath and therefore may be fully conscious when their throat is cut.

Pictures from www.factoryfarm.com

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