645. Wounding a Sheretz, Squeezing Fruit

Shabbos 8:9

When it comes to Shabbos laws, the eight creeping things (rodents and lizards) mentioned in the Torah have hides similar to those of domestic animals, wild animals and birds. Other small, crawling creatures are not considered to have such hides, so one would not be liable for wounding them. If a person wounds a domestic animal, a wild beast, a bird or one of the eight creeping things named by the Torah, he is liable. This is true both if he made an open wound that bleeds or a bruise reflecting internal bleeding.

Shabbos 8:10

One who squeezes fruit to extract its juice is liable for extracting. A person is not liable until he extracts a volume of juice equal in size to a dried fig. Under Biblical law, a person would only be liable for pressing grapes and olives. One is permitted to squeeze grapes directly onto food because a liquid that is absorbed into food is considered like the food itself. Therefore, one would be considered to be extracting food from food (which is permitted). However, if one squeezes fruit juice into a vessel that does not contain food, he is liable for pressing the fruit. The same is true if one milks directly into food or if one sucks with his mouth, he is not liable. A person is only liable for milking into a vessel.