French animal generator
Use classes
You should consider making animals a class, since you intend to make many of them that all have the same types of characteristics.  This is exactly what classes are good for.  I've taken the liberty of creating a characteristics dictionary for easy characteristic assignment using the data read from files
Don't repeat yourself
You do most things 5 times in a row (one for each characteristic).  You can avoid this in most situations.  For reading data, you can stuff each set of characteristics into one element of a dictionary.  For assigning characteristics, you can randomly select one item from each element of that dictionary.
Here's a crack at your code, revised:
import random

documents = [
    &quot;ani_nom.txt&quot;,
    &quot;ani_adj.txt&quot;,
    &quot;ani_ori.txt&quot;,
    &quot;ani_cor.txt&quot;,
    &quot;ani_cou.txt&quot;
    ]

data = {}

for document in documents:
    try:
        data.update({document.split(&quot;.&quot;)[0]: [line.strip() for line in open(document)]})
    finally:
        close(document)


class Animal(object):
    def __init__(self):
        self.characteristics = dict(
            ani_nom=None,
            ani_adj=None,
            ani_ori=None,
            ani_cor=None,
            ani_cou=None
        )

    def assign_all_characteristics(self):
        for characteristic in self.characteristics:
            self.characteristics[characteristic] = random.choice(data[characteristic])

    def print_random_characteristics(self):
        num_to_print = random.randint(1, 5)
        characteristics_to_print = list(self.characteristics.values())
        print &quot;\n&quot;.join(characteristics_to_print[:num_to_print])

number_of_animals = 120
for _ in range(number_of_animals):
    animal = Animal()
    animal.assign_all_characteristics()
    animal.print_random_characteristics()