Document Details

Document Type : Thesis 
Document Title :
Growth and Dynamics of Reproduction in Some Fishes of Family Lethrinidae, In The Red Sea, of Jeddah-Saudi Arabia
دراسة النمو وديناميكية التكاثر في بعض أسماك عائلة الشعور بالبحر الأحمر بمنطقة جدة بالمملكة العربية السعودية.
 
Subject : Growth and Dynamics of Reproduction in Some Fishes of Family Lethrinidae, In The Red Sea, of Jeddah-Saudi Arabia 
Document Language : Arabic 
Abstract : This study was conducted on three types of letherimus fish family, which represents 19% of the commercial fisheries of the Red Sea. We can use this study in fisheries organizing and the development of fish production and the preservation of fish stocks in addition to the aquaculture processes. The study was conducted on three types including: Letherimus elongates, Letherimus mahsena and letherimus lentjan All samples were collected throughout the year and the estimation of the age, growth rates in height and weight and the relationship between height and weight were successfully done. Also there were a study of reproduction and histological study for the gonads. • Fish common sizes in the fisheries started from 22 cm to 37 cm. Loops on the rinds through which ages are known appears in the period from June to July each year. • The dominate immersion groups in the fisheries of feeling in both Letherimus elongates and letherimus lentjan are 2 - 3 years. As for Letherimus mahsena, immersion 3-5 years is the dominant. • The highest rate of growth in length is in the first year and the second year of age and declines thereafter, as opposed to the rate of growth in weight, which increases with age. • Breeding season extends from 4 to 5 months from May to August. • Fish reach their first sexual maturity when their length becomes 22.9 - 22.7 cm in Letherimus elongates 21 - 21.6 cm letherimus lentjan and 22.3-22.7 cm in Letherimus mahsena.This corresponds to the second year of age. • We found that females dominated fisheries in the short lengths (ages), while males prevail in the long lengths (ages) and that is because the possibility of the existence of the of effeminate phenomenon, as it appears also in the sectors of histological gonads of these fish. • From the histological examination of the gonads it was shown that there are six stages of development for males and females. Reproductive products get out in periods and not all at once. • With the study of these fish feeding we come to discover that they are animal nutrition. They are crustaceans, mollusks and skin polychaete worms and small fish. 
Supervisor : Dr.altaf Ezzat 
Thesis Type : Doctorate Thesis 
Publishing Year : 1411 AH
1990 AD 
Co-Supervisor : Dr.Elham Wasef 
Added Date : Monday, March 9, 2015 

Researchers

Researcher Name (Arabic)Researcher Name (English)Researcher TypeDr GradeEmail
فايزه عبدالرحمن باوزيرBa-Wazeer, Fayza Abdul-RahmanInvestigatorDoctorate 

Files

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 37845.pdf pdf 

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