I'll poke my head into the conversation----
Ive not worked at a large animal slaughterhouse but I have worked for a live hange poultry processing plant. Want to know the WHOLE process?? (and yes I have worked in every dept from live hang to pack out)
The chicken as you know are grown in commercial houses which house roughly 5,000 chickens per house. these houses are 2-3 football fields long and about as wide as a football field, so they are long skinny houses. You have two types of chicken growers, you have broilers and hatchers.
With broilers the eggs are raised in a commercial hatchery with the utmost sanitary conditions when they are hatched they are taken on a chicken bus in crates and taken to a farm where they are placed in the chicken house. For 6-8 weeks the farmer feeds the chickens to company specifications, and every round the houses are inspected by the USDA to make sure the house is fit to raise chickens in. After 6-8 weeks the larger chicken trucks with the cages are brought in and they catch chickens, it takes a crew of 10-12 people (truck drivers included) to catch them and it is an all-night task.
Then the chickens must be kept a certain degree. When they arrive at the processing plant, they are backed up to a large row of fans that maintains a certain air temperature while the chickens wait to be offloaded and put on the line. If the chicken gets out or is dead they remove it before it ever hits the line. The chickens that are alive and loose, cannot go on the line because of possible contamination issues. There is a small flock of chickens that hang out around the chicken plant because 2-3 from each shift gets loose.
Now once they are in the building they are live hung upside down by their feet, now of course the chickens are flopping as chickens do, they go through a long tube that when they enter, the cross a high voltage electrical wire that kills them instantaneously. While the chickens are going in the shock tube, an audio recording of Muslim blessings are played over and over. This is a requirement of company customers, the chickens have to be blessed before they are killed. It sounds ridiculous but it is true.
Once they come out of the shock tube, they are defeathered, heads are cut off then they go into evisceration where all of the guts are removed. This is done mechanically and manually to ensure that all the guts are removed. If guts are found in the production area of the plant USDA shuts the place down.
Once they are gutted - they go into the chiller where they remain for up to two hours. If the chickens are too warm they cannot run them on the line in production.
when they come out of the chiller they come down a chute and into a bin where a line loader (a la me) would load them onto cones to start the processing part. First the drums were cut off, then the wings, then the breast, then the thighs, and then the tenders. At the end of the line there is a scraper that scrapes left over meat off the carcass into a bin that goes to pieces. The pieces are then boxed, frozen, and then shipped to dog food companies (I do believe we shipped to Eukanuba at one point)
Now what happens to each part??
They go on to a belt after being processed and sent to pack out where they were weighed, bagged, boxed, and labelled. They had to be inspected 3 times, once by QA, once by USDA and once by HACCP. (we called it hasip). If it didnt get by QA it sure as heck was not going to get by the other two.
The breast fronts are put on a belt and sent to the breast table where we do the following types of cuts (named for the company ordering it)
Carolina (the shoulder ball was removed) bones removed and cut in half
butterfly - no cutting but removed bones
Fat-Free, all fat and bones removed - this is what you eat when you order chicken from Applebees.
4-10 - butterflys bones removed but leave the shoulder ball
Then there are the thighs which were sent to a thigh table, inspected for bones, fat removed, then sent to pack out
the tenders had the tendons cut off and boxed. This was by far the easiet job but the most tedious.
The drumsticks were sent directly to pack out as there is no need to further process them.
and thats the story of a poultry production plant. I dont think any part of it was inhumane and trust me if there is any inkling of being inhumane USDA shuts the plant down for inspection (there is a USDA office on site of this facility) As a matter of fact plant employees and USDA workers are not allowed to talk to each other. They may stand side by side on the line but they cannot converse. This is because they dont want the employees bribing the USDA or the USDA bribing the employees. This is company policy not USDAs.
I feel that my local chicken plant is humane.
And yes I am very much a carnivore and animal lover.