scholarly journals Breeding pattern of Oreochromis niloticus (Linnaeus, 1758) versus native congeneric species, Oreochromis macrochir (Boulinger, 1912), in the upper Kabompo River, northwest of Zambia

2021 ◽  
Author(s):  
Arthertone Jere ◽  
Wilson W. L. Jere ◽  
Austin Mtethiwa ◽  
Daud Kassam
Keyword(s):  
Oreochromis Niloticus ◽  
Congeneric Species

scholarly journals Breeding pattern of Oreochromis niloticus (Linnaeus, 1758) (Pisces: Cichlidae) versus native congeneric species, Oreochromis macrochir (Boulinger, 1912) in the upper Kabompo River, northwest of Zambia

2021 ◽  
Author(s):  
Arthertone Jere ◽  
Wilson Jere ◽  
Austin Mtethiwa ◽  
Daud Kassam
Keyword(s):  
Sex Ratio ◽  
Oreochromis Niloticus ◽  
Breeding Population ◽  
Cold Season ◽  
Biological Research ◽  
Congeneric Species ◽  
Wet Season ◽  
Males And Females ◽  
The Impact ◽  
Somatic Index

Investigating the determinants of reproductive biology of fishes is an essential component of biological research. Breeding pattern was investigated to determine the impact of exotic Oreochromis niloticus on the native congeneric Oreochromis macrochir in the upper Kabompo River. Gonado-somatic index and sex ratio was used to investigate the breeding pattern in both invaded (where O. niloticus is present) and uninvaded (where O. niloticus is absent) sections of the river. Oreochromis macrochir was the only native congeneric species found in both sections. Results showed that the overall gonado-somatic index means for both sexes of O. macrochir in both sections were similar. For O. niloticus in invaded section indicated all year reproduction though reduced spawning in cold season (May-June), but with increased spawning activity in wet season (February-March). In O. macrochir, males and females were found breeding in both dry and wet seasons only, as for cold season no reproduction was recorded. Sex ratio (females: males) was 1:1.3 and 1:1.7 for O. niloticus and O. macrochir respectively, and both significantly deviated from the sex ratio of 1:1 (ꭓ2=8.42 and 9.37; p<0.05). Oreochromis niloticus formed the most abundant fish caught 221(63.5%) than O. macrochir 127(36.5%). Our study has revealed that O. niloticus was able to spawn in all seasons with 23% higher breeding population than O. macrochir, which explains the suppression in the abundance. We expect O. niloticus to invade further downstream of the Kabompo River due to natural dispersion.

Ultrastructure of Testicular Spermatozoon of the Fish Oreochromis Niloticus

1988 ◽  
Vol 46 ◽  
pp. 278-279
Author(s):  
T. Guha ◽  
A. Q. Siddiqui ◽  
P. F. Prentis
Keyword(s):  
Electron Microscope ◽  
Oreochromis Niloticus ◽  
Osmium Tetroxide ◽  
Sperm Cells ◽  
Adult Fish ◽  
Testicular Sperm ◽  
Thin Sections ◽  
Important Fish ◽  
Testicular Spermatozoon ◽  
Diamond Knife

Tilapia, Oreochromis niloticus, is an economically important fish in Saudi Arabia. Elucidation of reproductive biology of this species is necessary for successful breeding program. In this paper we describe fine structure of testicular sperm cells in O, niloticus.Testes from young adult fish were fixed in gluteraldehyde (2%) and osmium tetroxide (1%), both in cacodyl ate buffer. Specimens were processed in the conventional way for electron microscopy and thin sections of tissues (obtained by cutting the blocks with a diamond knife) were stained by ura- nyl acetate and lead citrate. These were examined in a Carl Zeiss electron microscope operated at 40 kV to 60 kV. Sperm cells were obtained from testes by squeezing them in cacodyl ate buffer. They were fixed in gluteraldehyde (2%) in the same buffer, air dried, gold coated and then examined in a Philips scanning electron microscope (SEM) operated at 25kV.The spermatozoon of O. niloticus is consisting of head, midpiece and tail (Fig. 1).

Ultrastructure of primary spermatocyte in fish (Tilapia: Oreochromis niloticus): The synaptonemal complex

1986 ◽  
Vol 44 ◽  
pp. 288-289
Author(s):  
T. Guha ◽  
A. Q. Siddiqui ◽  
P. F. Prentis
Keyword(s):  
Fine Structure ◽  
Electron Microscope ◽  
Synaptonemal Complex ◽  
Oreochromis Niloticus ◽  
Short Communication ◽  
Primary Spermatocyte ◽  
Mitotic Division ◽  
Meiotic Cell ◽  
Electron Microscope Level ◽  
Homologous Chromosomes

The Primary Spermatocytes represent a stage in spermatogenesis when the first meiotic cell division occurs. They are derived from Spermatogonium or Stem cell through mitotic division. At the zygotene phase of meiotic prophase the Synaptonemal complex appears in these cells in the space between the paired homologous chromosomes. Spermatogenesis and sperm structure in fish have been studied at the electron microscope level in a few species? However, no work has yet been reported on ultrastructure of tilapia, O. niloticus, spermatozoa and spermatogenetic process. In this short communication we are reporting the Ultrastructure of Primary Spermatocytes in tilapia, O. niloticus, and the fine structure of synaptonemal complexes seen in the spermatocyte nuclei.

Efektivitas Penggunaan Asam Formiat Dan Propionat Pada Pembuatan Silase Darah Terhadap Nilai Kecernaan Tepung Darah Pada Ikan Nila (Oreochromis niloticus)

2016 ◽  
Vol 2 (2) ◽  
pp. 63
Author(s):  
Rosmawati Rosmawati ◽  
Reza Samsudin
Keyword(s):  
Oreochromis Niloticus

Penelitian ini bertujuan untuk mengetahui dosis asam formiat dan propionat yang tepat pada pembuatan silase darah yang dapat meningkatkan kecernaannya pada ikan nila (Oreochromis niloticus). Rancangan percobaan pada penelitian ini adalah Rancangan Acak Lengkap dengan 6 perlakuan dan 3 ulangan. Perlakuan yang diberikan adalah perlakuan kontrol (Darah tanpa disilase), silase dengan dosis asam foemiat dan propionat (3:0%; 2,25:0,75%; 1,5:1,5%; 0,75:2,25%; 0:3%). Ikan yang digunakan dalam penelitian ini adalah ikan nila dengan bobot rata-rata 7,0 gram/ekor dengan padat tebar 20 ekor/akuarium. Parameter yang diamati yaitu nilai kecernaan protein, kecernaan lemak, kecernaan energi, dan kecernaan total. Hasil penelitian ini menunjukan bahwa pemberian dosis asam yang berbeda memberikan pengaruh yang berbeda nyata (P<0,05) terhadap nilai kecernaan protein, kecernaan lemak, kecernaan energi, dan kecernaan total pada ikan nila. Perlakuan pemberian silase dengan dosis asam formiat dan propionat 1,5:1,5% dapat meningkatkan nilai kecernaannya pada ikan nila, dengan nilai kecernaan protein 94,66%, kecernaan lemak 88,71%, kecernaan energi 92,58%, dan kecernaan total 90,27%.Kata kunci : Silase darah, Asam formiat dan propionat, Kecernaan, Ikan Nila

Manejo experimental de alevinos de tilápia (Oreochromis niloticus) alimentados com ração comercial e pre/probióticos

PubVet ◽  
2018 ◽  
Vol 12 (8) ◽  
pp. 1-9
Author(s):  
Luis Arthur Rodrigues de Andrade ◽  
Tatiana Maslowa Pegado de Azevedo
Keyword(s):  
Oreochromis Niloticus
Sign in / Sign up

Export Citation Format

Share Document