How Long Does it Take for Shrimp to Grow Big Enough to Eat?

Edible shrimp generally have four stages of development after they hatched from their eggs. Viable eggs for hatching undergo immediate cleavage formation after they spawn. The first stage is completed in 12 to 18 hours or more, depending on the species. Subsequent progression from one stage to the next shows differentiation in the creature's systems and physical appearance. Changes happen sequentially before the shrimp attain full edible size in three or four weeks.

The naupliar stage varies depending on the shrimp species. For instance, the Penaeus kerathurus (tiger or striped shrimp) has six naupliar stages, while brine shrimp only have four. During this stage, rudimentary appendages (antennae and mandible) develop, and the posterior region divides and thins out. The beginnings of the spine, carapace and digestive tract also appear. A set of setae and articulations also come forth, and mouth tissues start to differentiate into the teeth. The shrimp's body enlarges and becomes longer.

In the protozae stage the shrimp physically develop further. The abdomen elongates considerably, together with the thorax. A spiny rostrum and a pair of compound eyes develop in stalks at the head. Walking limbs called pereiopods, as well as a swimming attachment anterior to the tail (uropod), also become visible. Bifurcation, or the process of creating several divisions on the shrimp's body, evolves further with additional spines.

The mysis stage allows further torso elongation, with mostly the swimming limbs (pleopods) developing into a fully functional part of the shrimp. The organism's pereiopods also become functional and a swimming tail appendage (telson) appears.

The final stage is attained, aided by proper nutrition, the right water conditions and proper oxygen levels. In tiger shrimps the female reaches a maximum length of 8.85 inches; the male elongates to a maximum of 7.08 inches. Average lengths in the same specie range from 5 to 6.5 inches for the female and 4.33 to 5.51 inches for the male.