Few Aspects of the Reproductive Biology of Oreochromis mossambicus (peter 1852) from Lower Anicut, Tamil Nadu, India

2019 ◽  
Vol 8 (1) ◽  
pp. 1
Author(s):  
P. Manivannan ◽  
R. Sivakumar ◽  
R. Mathialagan
Keyword(s):  
Reproductive Biology ◽  
Tamil Nadu ◽  
Oreochromis Mossambicus

scholarly journals REPRODUCTIVE BIOLOGY OF GNETUM LATIFOLIUM BLUME (GNETALES) IN TAMIL NADU

2016 ◽  
Vol 3 (2) ◽  
pp. 75-78
Author(s):  
Karupusamy S
Keyword(s):  
Reproductive Biology ◽  
Western Ghats ◽  
Tamil Nadu ◽  
Low Frequency ◽  
Seed Maturation ◽  
Male Population ◽  
Dioecious Plants ◽  
Very Low Frequency ◽  
Forest Sites

The reproductive biology of Gnetum latifolium Blume studied in four different forest sites of Tamil Nadu. G. latifolium reported to have dioecious plants with less number male population in all the selected areas. Entamophilous cues observed with common anaemophily and pollinator may be flies. Pollination dropsare also reported in young ovules. The seed maturation and germination frequency observed with very low frequency in all the selected population whereas in high number of abortive ovules reported in Western Ghats.

Fine structure and possible functions of the hermaphrodite duct of some pulmonate snails (Mollusca: Gastropoda)

1990 ◽  
Vol 48 (3) ◽  
pp. 68-69
Author(s):  
Alan N. Hodgson
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Seminal Vesicle ◽  
Reproductive Biology ◽  
Light Microscope ◽  
Light Microscope Level ◽  
Transmission Electron ◽  
Standard Techniques

The hermaphrodite duct of pulmonate snails connects the ovotestis to the fertilization pouch. The duct is typically divided into three zones; aproximal duct which leaves the ovotestis, the middle duct (seminal vesicle) and the distal ovotestis duct. The seminal vesicle forms the major portion of the duct and is thought to store sperm prior to copulation. In addition the duct may also play a role in sperm maturation and degredation. Although the structure of the seminal vesicle has been described for a number of snails at the light microscope level there appear to be only two descriptions of the ultrastructure of this tissue. Clearly if the role of the hermaphrodite duct in the reproductive biology of pulmonatesis to be understood, knowledge of its fine structure is required.Hermaphrodite ducts, both containing and lacking sperm, of species of the terrestrial pulmonate genera Sphincterochila, Levantina, and Helix and the marine pulmonate genus Siphonaria were prepared for transmission electron microscopy by standard techniques.

SEM and TEM observations of sperm development in the testis of the freshwater fish Oreochromis mossambicus

1990 ◽  
Vol 48 (3) ◽  
pp. 58-59
Author(s):  
Daryl A. Cornish ◽  
George L. Smit
Keyword(s):  
Morphological Characteristics ◽  
Oreochromis Mossambicus ◽  
Breeding Cycle ◽  
Limited Information ◽  
North West ◽  
The North ◽  
Sem And Tem ◽  
Sperm Development ◽  
Ultrastructural Characteristics ◽  
The University

Oreochromis mossambicus is currently receiving much attention as a candidater species for aquaculture programs within Southern Africa. This has stimulated interest in its breeding cycle as well as the morphological characteristics of the gonads. Limited information is available on SEM and TEM observations of the male gonads. It is known that the testis of O. mossambicus is a paired, intra-abdominal structure of the lobular type, although further details of its characteristics are not known. Current investigations have shown that spermatids reach full maturity some two months after the female becomes gravid. Throughout the year, the testes contain spermatids at various stages of development although spermiogenesis appears to be maximal during November when spawning occurs. This paper describes the morphological and ultrastructural characteristics of the testes and spermatids.Specimens of this fish were collected at Syferkuil Dam, 8 km north- west of the University of the North over a twelve month period, sacrificed and the testes excised.

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