Shrimp thread can be eaten without removing it.
No matter what species of shrimp, there will be a black thread-like object on the back, this is the so-called "shrimp line". Shrimp line is actually shrimp intestines, there will be some residual feces, so even if you do not want to remove the shrimp line, eat just affect the taste, will not cause harm to health.
If it is a fishing boat freshly caught shrimp, not to shrimp line is also possible, or very small shrimp do not have to go to the shrimp line, because the residual feces inside is very little very little, but shallow sea farming shrimp is best to remove the shrimp line, to avoid affecting the taste.
Shrimp line notes:
In the natural situation, if the natural bait is sufficient, then the shrimp's entire intestinal tract is full of a continuous dark line; on the contrary, in the absence of bait, the shrimp's "shrimp line" would be This is the phenomenon of "empty gut".
In artificial culture conditions, shrimp after dietary domestication can ingest feed, and these feeds are often very high protein content. These foods are indeed a little dirty after being digested, and it is relatively cleaner to remove the "shrimp threads" and then eat them.
The above content refers to Baidu Encyclopedia - shrimp thread