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Objective: Histological study of the mature “Penaeus semisulcatus” shrimp of Persian Golf and Oman Sea.
Design: Making serial plane sections perpendicular to the surface. Animals: 100 mature healthy “Penaeus semisulcatus” shrimps.
Procedures: One hundred of mature healthy Penaeus Semisulcatus
shrimps were selected immediately after fishing from Jask Port
and fixed by plunging into 10% buffer formalin after removing the cuticles and muscles ,and injecting of 10% buffer formalin into the gill sinus simultaneously. After fixation, morphology of the ovaries
were studied under stereo-microscope and then routine histology
lab method were used and paraffin blocks were made 6pm sections were cut and stained with H&E and studied under light microscope. Results: A pairs of symmetric ovaries lied in the body and each contained three, frontal, lateral and distal lobes.
4 types of oocytes, namely, Resting oocyte, Developing oocyte,
Expanding oocyte and mature oocyte were observed in the ovaries.
The Resting oocyte was the small cell with round and euchromatic nucleous and little basophilic cytoplasm around it. The developing oocytes were surrounded into the tubular sacs. Each sac contained
8-50 oocytes arranged in lines. The expanding oocytes were too
much larger than the developing oocytes and lied in the follicular
sacs. The mature oocytes were the largest oocytes and lied most peripheral in the follicular sacs. The most percentages of oocytes were types 2&4 and oocytes types 1 &3 were rare in present studied samples.
Conclusion: The histological structure of the ovary in the species
of this study had some similarities as well as differences with two other species of shrimps reported before, which is mentioned completely in the paper. J. Fac. Vet. Med. Univ. Tehran. 59, 1: 39.42, 2004.