First, it can be judged by the fetal spot on the abdomen of the female fish. During the breeding season, the mother fish will have some fetal spots on its abdomen. However, at the time of conception, these fetal spots are not too obvious, their color is relatively light, and the area is relatively small. However, as the birth period approaches, these fetal spots will become more and more obvious. When it comes to labor, these spots are easy to observe, they are large and dark in color.
It can also be judged by the swimming state of the female fish whether they are about to give birth to small fish. In normal times, the female fish's swimming state will be more active. However, when they are in labor, they are relatively quiet, do not swim often, and sometimes seek a safe and stable place to hide themselves in order to give birth safely. Even if they swim, their trajectories are irregular and slow, and they are easy to observe.
When small fish are about to be produced, the appetite of the female fish will be seriously reduced, and there will often be no reaction when feeding.
In addition to the fetal spots on the abdomen, you can also judge by observing the shape of the abdomen of the female fish. If the belly of the female fish is square, it is about to give birth. This is because the arrangement of the roe is very regular and square. Moreover, if the anus protrudes, it also indicates that they are about to give birth.
