Just like humans, pigs are averse to confined spaces. Hence it is best not to rear more than 30 in the same pen, or they are likely to engage in bloody group battles and gain weight slowly, thus causing serious losses for farmers.
跟人一樣，豬也會感覺空間壓力，因此最好同一空間圈養頭數不超過三十頭，否則打起群架，到處血淋淋，業者反而損失慘重。