<div>Background: The success or failure of spawning in any population affects the fishery. Hence, studies on spawning, maturation, fecundity&nbsp;and length at first maturity become essential in drafting management strategies. The detailed information on reproductive traits of Sphyraena obtusata will be helpful in sustainable management and conservation in the study area. 
 
Methods: Three hundred and fifty five specimens of S. obtusata were collected fortnightly from Mangaluru and Malpe fishing harbors during August 2019 to March 2020. Maturity of gonads was examined by macroscopic and histological investigations. Spawning periodicity was worked out based on maturity stages and seasonal gonadosomatic index. Gravimetric method of analysis was employed to evaluate the fecundity from randomly collected samples of gravid females. 
 
Result: Overall sex ratio revealed that the population had significantly higher (p&lt;0.05, X2 test) proportion of females than males. The length at 50% maturity (Lm50) for females and males was estimated at 21.1 and 21.5 cm respectively. The gonadosomatic index (GSI) and the availability of matured individuals for both the sexes in various percentage indicated a prolonged breeding period from October to March with peaks in November and December. The absolute fecundity varied from 91,942 eggs (20.0 cm TL) to 1,34,445 eggs (27.0 cm TL) with an average of 1,12,878 &plusmn; 2,984 hydrated oocytes per female.</div>

Sexual Maturity, Spawning Periodicity and Fecundity of Obtuse Barracuda Sphyraena obtusata (Cuvier, 1829) along Karnataka Coast, Southeastern Arabian Sea

<div>Background:&nbsp;Yangtze finless porpoise (YFP, Neophocaena asiaeorientalis), is the first class protected animal in China. In order to analyze the adaptive evolution of fecundity traits in YFP, the rapidly evolving gene families of YFP were obtained. At the same time, the major genes controlling ovulation, GDF9, BMP15, FSH&beta; and FSHR were also analyzed. 
 
Methods: Orthofinder software was employed to search homologous genes based on protein sequence. CAF&Eacute; software was used to obtain the expansion and contraction gene families of YFP. Then, GO terms and pathway enrichment analyses were performed using TBtools software and Swissprot database. PAML package was used to calculate Ka/Ks (i.e., &omega;). Evolution rate changes in the positive selected genes were examined using the GU99 process in Diverge (v3.0) program. 
 
Result: In YFP, 501 rapid expansion gene families GO enrichment results showed that the reproductive activities related pathways were mainly three significant enrichment process, participation of germline stem cells maintain androgen receptors signaling pathways regulating and male reproductive tract stem cell population to maintain. The most significant GO terms of 220 rapidly contraction gene families associated with reproductive activities mainly consisted of biological processes which were involved in positive regulation of estrogen secretion, mating and estrogen metabolic process. GDF9 and BMP15 genes exhibited purifying selection. However, significant signs of positive selection were detected in FSHR and FSH&beta; genes, but only FSH&beta; showed specific changes in the YFP lineage.</div>

Sexual Maturity, Spawning Periodicity and Fecundity of Obtuse Barracuda Sphyraena obtusata (Cuvier, 1829) along Karnataka Coast, Southeastern Arabian Sea

​The Analysis of Reproduction-related Genes Provides Insights into the Adaptive Evolution of Fecundity Traits in Yangtze Finless Porpoise

The Analysis of Reproduction-related Genes Provides Insights into the Adaptive Evolution of Fecundity Traits in Yangtze Finless Porpoise