A way to start a paragraph that I really like is to introduce a counterargument that I believe I can disprove. I only do this, of course, if I believe I have good arguments speaking against it.

Many people consider animals as inferior beings because animals can not think in a rational way or speak.

Having stated the counterargument, I will support it with a source.

Rolston (1988) states that ‘animals can not live ethically, cognitively, and critically in those superior human ways’. And he concludes that there is no moral reason not to eat animals that have no morals.¹ Hsiao (2015) grants that animals have feelings and feel pain, but an infliction of pain on animals can be considered acceptable as it depended largely on what we think about the moral status of animals. He argues that ‘sentience alone was not sufficient for being granted a moral status’. He continues that ‘even though animals experience pain as physically bad, their experience of it is not morally bad’. This harm done to animals is not of a moral kind, and since animals have no moral status, it is not wrong to eat meat, even if this is not essential to nutrition².
^{1 Holmes Rolston III. (1988): Environmental Ethics. Philadelphia : Temple University Press, 1988.
2 Hsiao, T. In Defense of Eating Meat. JAgricEnvironEthics 28, 277–291 (2015). https://doi.org/10.1007/s10806-015-9534-2}
 

Then I will explain the counterargument as I understand it.

These arguments are based on the idea that animals do not have a moral status because they can not intellectually negotiate their interests in a social contract with human beings.

After that, I will refute the counterargument as I understand it. This will serve as my paragraph thesis statement.

However, in my view, the fact alone that they can not defend themselves verbally against human beings can not suffice as reason for getting killed and eaten.

Adverbial clauses make your sentence more informative, lively and colourful. They have the same function as adverbials in our sentences. The information provided in adverbial clause, however, is too much to be expressed with just one short adverb. Adverbial clauses can follow a main clause. Then they usually do not need a comma. The focus of the complex sentence lies on the adverbial clause. It is important information we need to understand the main clause.

The question arises whether it would become more acceptable to kill animals if they were treated kindly and would not suffer much or long.

Adverbial clauses preceding a main clause are usually separated with a comma. As adverbial clauses are usually rather long, we also often put them at the beginning of the sentence. In this case, they are usually separated by a commma.

Before the pigs are put to death, they have to smell the blood of their fellow animals, which frightens them.
Although eating meat seven days a week is a fairly new habit in Germany, strong resistance has alredy been forming against it.
If the prices for meat would not be dropping all the time, people would start eating less meat.
Even though naturally and organically produced meat is available, most people tend to buy cheap meat at the discouter.

We see that the sentence would not really make much sense without the information in the adverbial clause. But there are also some adverbial clauses that always take a comma. In general, if an adverbial clause takes a comma, the focus of interest is shifted to the main clause. The meaning of adversative adverbial clauses contradicts or qualifies the first sentences to a strong degree. Have look at the examples.

Although some animal protection regulations have been introduced, the living conditions of animals have deteriorated.
(Even) Though some animal protection regulations have been introduced, the living conditions of animals have deteriorated.
The living conditions of humans have improved, whereas those of animals have deteriorated.
Some animal protection legislation has been passed; consequently, the living conditions of animals have deteriorated.

If an adverbial clause takes a comma, the focus of interest is shifted to the main clause. In the second sentence the focus is on the obviousness of the change of living conditions. You can also hear it when you read the sentences correctly. This is an interesting phenomenon, and that’s why I have put an exercise for you below the example. Here you can practise recognizing the focus shift.

It is obvious that the living conditions of animals have deteriorated because the industry has been optimizing their means of production to increase profits.

It is obvious that that the living conditions of animals have deteriorated, because the industry has been optimizing their means of production to increase profits.