Developmental stages observed during experimental culture of the egg bearing cyclopoid copepod Oithona similis (Claus, 1866)

Abstract

Experimental culture of the marine cyclopoid copepod Oithona similis were made to assess their different developmental stages and developmental time in laboratory conditions. Cost-effective techniques for breeding, growth, development of O. similis and relevant micro algal feed production were ascertained by suitable experiments. The results revealed that the span of life cycle stages of O. similis after fertilization lasted for 23 days. The life cycle had five naupliar stages such as: N1 – 1st day; N2 – 3rd day; N3 – 5th day; N4 – 8th day and N5 – 10th day. The naupliar stage was followed by six copepodid stages (C1 – 12th day; C2 – 14th day; C3 – 16th day; C4 – 19th day; C5 – 21st day; C6 – 23rd day) and a single pre-adult stage in the laboratory conditions. Maximum survival of 30% copepodids was attained during 23 days of rearing in culture flasks of 1ℓ capacity provided with micro algal diet size <5µ.