Would Jesus have advocated the disgusting torture that animals endure throughout their lives in present-day slaughterhouses? While you clearly say eating dead animals is okay by God and the Bible, the Bible also says slavery is fine and selling one's daughter is okay. So, is absolutely everything in the Bible truly applicable to present-day life?
For a very good question, you ruined its presentation with inconsistencies and poorly framed reasoning. I wonder what it is with animal-rights activists that make so many of them sound like mindless hate mongers? I will happily accept the backhanded compliment that I was clear in proving that the Bible does allow men to eat meat.
You ask if Jesus would approve of modern slaughterhouses, but then question whether the Bible is useful. So what does it matter to you what Jesus would do if you doubt the book that tells us of Jesus?
Then there is the problem of your baseless assumptions. You assume that animals are tortured in slaughterhouses -- not just in the butchering, but you state the torture goes on their entire lives. A very blatant lie and an obviously false statement. Cows, chickens, hogs, and similar beasts are not raised in slaughterhouses, so, therefore, they could not be tortured in slaughterhouses their whole lives.
You question the practice of eating dead animals, does that mean you prefer people eating live animals? Yes, I'm being very sarcastic, but I'm dealing with thick-skulled people here.
The Bible does not say that all slavery is fine. The slave system described in the Bible has little to do when the slave system used in the United States in its early history. See articles on Slavery for a more accurate portrayal of what God did to regulate man's desires for slaves.
Similarly, the Bible doesn't give blanket approval to the selling of a person's children -- let alone his daughters. There was a debtor system where a man could place his family and himself into temporary indentureship to pay off his debts. But notice that the person did it to himself by placing his family into debt. Second, the term of service was clearly limited. Third, the person sold for debts was strongly protected by laws in regards to what could happen to him or her. And fourth, there were laws requiring near kinsmen to buy relatives out of their debt bondage if it was within their ability.
Thus, the presentation of your questions misrepresents the Bible's position. The comparison doesn't hold.
But let's skip all the silliness and address the one good question that you asked: "Is absolutely everything in the Bible applicable to today's life?" The answer is no. The Bible tells us what wicked people did and said. Just because these were recorded in the Bible, it doesn't mean they are there to follow. Quite the opposite. They are there as warnings. "Now these things became our examples, to the intent that we should not lust after evil things as they also lusted" (I Corinthians 10:6). The Bible also contains the advice of people who were not well informed. For example, the book of Job contains the ill-thought-out advice of three of Job's friends. They are recorded so that we can see why men often reason poorly, but they are not meant to be followed.
Then there is a need to understand the nature of the Bible. The Old Testament records the history of God's dealing with mankind. While we can learn principles and applications (Romans 15:4), it is not the law we live under. For example, Paul argues strongly that circumcision (a practice required by Israelites under the Old Law) is not applicable to Christians under the Law of Christ (Galatians 5:1-4). See "Why We Do Not Follow the Old Testament" for more details.
Peter states that the Bible contains everything we need to live righteously. "As His divine power has given to us all things that pertain to life and godliness, through the knowledge of Him who called us by glory and virtue" (II Peter 1:3). But it doesn't mean that everything in the Bible is directly applicable to us. You have to use your head to "understand what the will of the Lord is" (Ephesians 5:17). It requires study. "Be diligent to present yourself approved to God, a worker who does not need to be ashamed, rightly dividing the word of truth" (II Timothy 2:15). Not that it is impossibly difficult. The Bible is understandable. But people who approach it as a means of justifying their preconceived notations are strongly motivated to distort the clear teaching to promote their false ideas. "Therefore, beloved, looking forward to these things, be diligent to be found by Him in peace, without spot and blameless; and consider that the longsuffering of our Lord is salvation--as also our beloved brother Paul, according to the wisdom given to him, has written to you, as also in all his epistles, speaking in them of these things, in which are some things hard to understand, which untaught and unstable people twist to their own destruction, as they do also the rest of the Scriptures. You therefore, beloved, since you know this beforehand, beware lest you also fall from your own steadfastness, being led away with the error of the wicked; but grow in the grace and knowledge of our Lord and Savior Jesus Christ. To Him be the glory both now and forever. Amen" (II Peter 3:14-18).
I find it odd that you chose to attack my question rather than focusing on answering what I clearly meant to ask. Also, I was shocked at how hateful you were toward me for a pretty basic question. I never said that I didn't believe in God, Christ, or the Bible's teachings, nor that you were wrong in your interpretations. I simply wanted the opinion of someone more learned in the field of theology than I am. After reading your email, please don't sarcastically mock me, my eyes welled up with tears because I don't understand why you were so mean when all you know about me comes from a three-sentence email. I realize I was a little worked up and sarcastic in my email, and I apologize for that. But to imply that I'm unintelligent, or a "hate monger", is just wrong. I have a 4.2 GPA at the second toughest high school in _______ - I'm not completely dumb.
You may have had some unpleasant encounters with vegans in the past, but please keep in mind that not all vegans are crazy people who run around naked and throw red paint on fur. I've never been to a protest in my life and wouldn't think of telling a meat-eater how stupid or ignorant they are. In my email, I wasn't questioning the Bible's teachings - I simply wanted to know the church's argument for the consumption of meat.
I'm glad to see that the strong approach opened your eyes to the wording of your prior message. Yes, I was well aware that you were "a little worked up and sarcastic." I answered as I did because Proverbs says, "Answer a fool according to his folly, lest he be wise in his own eyes" (Proverbs 26:5). It is interesting that you enjoy dishing out sarcasm, but well up with tears when you are responded to in kind.
Despite your protest, you did not ask about arguments concerning the consumption of meat. You stated in your first note, "you clearly say eating dead animals is okay by God and the Bible," which implies you have read the arguments presented on this website. After scolding you for the framing of your question, I did answer your question about whether everything in the Bible is applicable today. As I said it was a good question even though it was presented poorly in your original note. If you are interested in what the Bible says about the eating of meat, please see the articles on vegetarianism.