scholarly journals Investigations on Gonadosomatic Index and Gonad Histology of Barred Spiny eel Macrognathus pancalus Hamilton, 1822 from Upper Assam, India

Author(s):  
Rimle Borah ◽  
Jyotirmoy Sonowal ◽  
Akash Kachari ◽  
Nipen Nayak ◽  
Shyama Prasad Biswas

Background: Macrognathus pancalus or barred spiny eel is a highly valued ornamental and food fish found in the Indian subcontinent. Due to the burgeoning population and their associated impacts, the population of the species is in rapid decline that necessitates time-bound intervention to conserve the species. The current investigation was undertaken to study the gonadosomatic index and gonad histology of Macrognathus pancalus collected from upper Assam, India.Methods: 500 samples of Macrognathus pancalus were collected from different water bodies such as wetlands, ponds, paddy fields, etc. from upper Assam, India during 2018-2019. Monthly samplings were carried out to evaluate the gonadosomatic index. The gonads were dissected out, measured and subsequently preserved for histological studies. Histological sections of preserved samples were prepared by employing accepted methodologies. The sections were then photographed using Leica DM 750 and gonadal staging was ascertained. Result: Gonadosomatic index studies revealed that it peaked in August in both males (3.45±0.18) and females (8.85±0.35), thereby indicating its spawning season. Minimum GSI values were observed during January in males (0.39±0.04) and in December in females (1.04±0.15) indicating the culmination of the breeding period and the advent of the preparatory phase. Macroscopic and microscopic examination unearthed five different phases of gonadal maturation. Gonadal staging through microscopic and macroscopic technique showed synchronicity with GSI values. 

Author(s):  
Sauliheen Qadri ◽  
Tasaduq H Shah ◽  
M. H. Balkhi ◽  
Bilal A. Bhat ◽  
F. A. Bhat ◽  
...  

The objective of the present study is to describe the phases of gonadal development and determine the spawning season of Schizothorax curvifrons in River Jhelum Kashmir. A total of 298 fish specimen were studied to analyse the gonadosomatic index and maturity stages of S. curvifrons. Five maturity stages namely Immature phase, Preparatory phase, Maturing phase, Ripe/spawning phase and Spent phase were observed in the gonads. Based on GSI values and gonadal conditions, April to June appears to be the spawning season for S. curvifrons


2012 ◽  
Vol 10 (2) ◽  
pp. 401-408 ◽  
Author(s):  
Luis Alberto Espínola ◽  
Horácio Ferreira Júlio Junior ◽  
Evanilde Benedito

The allocation of assimilated energy may be influenced by seasonal changes, growth, and reproductive cycle of fish, food consumption and environmental conditions. The objective of this research was to evaluate the energetic variations of Cichla kelberi in the upper Paraná River floodplain, analyzing the caloric content in muscles, gonadosomatic index (GSI), and the condition factor between assessed systems, sex, and stage of gonadal maturation. The results obtained in the present study permit assuring that this is a species that efficiently converts the resources of the environment into energy. Although presenting higher condition factor in the environment where there is a greater ease in getting food (Paraná subsystem), the energy identified in the muscles was the same in both subsystems. During the process of gonadal maturation there is optimization in energy accumulation in the muscles of females, before and after reproductive period, and somatic growth occurs significantly when the individual is not reproducing. Further detailed studies on ecological mechanisms influencing the success of the species, as the presence of competitors and preference for native preys, are needed to implement effective management measures aimed at preventing that the species proliferation in the environment is even more damaging to local biodiversity.


Author(s):  
M.M. Meshram ◽  
Mridula Rajesh ◽  
K.M. Rajesh ◽  
N.K. Suyan

Background: The success or failure of spawning in any population affects the fishery. Hence, studies on spawning, maturation, fecundity 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 less than 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 ± 2,984 hydrated oocytes per female.


2004 ◽  
Vol 21 (2) ◽  
pp. 193-200 ◽  
Author(s):  
José Enemir dos Santos ◽  
Nilo Bazzoli ◽  
Elizete Rizzo ◽  
Gilmar Bastos Santos

The reproductive biology of Iheringichthys labrosus (Lütken, 1874) was studied in Furnas reservoir, Minas Gerais, Brazil. The fishes, 323 males and 817 females, were captured bimonthly from August 1993 to July 1994 by using gill nets with 3-10 cm mesh size. Gonadal maturation of the specimens was analyzed through macro and microscopical characteristics of the gonads. The secretory activity of the tubules of the caudal region of the testis was analyzed during the maturational testicular cycle. Females and males were in reproductive activity throughout the year in the reservoir. The peak of advanced maturation/mature stages occurred from October to January and of spawned/spent from February to May. The spawning of I. labrosus was identified as fractional or multiple type: occurring in the reservoir or in tributaries around it. The oocyte development of the species was asynchronous as different clusters of oocytes occurred simultaneously in the ovarian parenchyma. The epithelium of the tubules of the caudal region of the testis was in high secretory activity during advanced maturation/mature stage and this activity was absence in resting. The gonadosomatic index followed gonadal maturation, and the hepatosomatic index of females was lowest in advanced maturation/mature probably due the contribution of the liver in the vitellogenesis. The variations of the stomach repletion index, coelomic fat and condition factor indicated that the feeding activity was reduced and that the energetic reserves were consumed during the reproductive period.


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Mônica Rocha de Oliveira ◽  
Sathyabama Chellappa

The reproductive aspects ofHemiramphus brasiliensiswere analyzed with a view to verify the temporal dynamics of reproduction. This paper presents data on sex ratio, length at first sexual maturity, macroscopic and histological aspects of gonad development, gonadosomatic index (GSI), reproductive period, and fecundity ofH. brasiliensis. The fishes were captured from the coastal waters of Rio Grande do Norte, northeastern Brazil. Females of this species predominated in the sampled population and were larger in size than the males. The length at the first sexual maturation of males was 20.8 cm and that of females was 21.5 cm. The macroscopic characteristics of the gonads indicated four maturation stages. Histological studies of gonads ofH. brasiliensisshowed six phases of oocyte development and four phases of spermatocyte development. The batch fecundity of this species was 1153 (±258.22) mature oocytes for 50 g body weight of female. The microscopic characteristics of gonad development indicate thatH. brasiliensisis a multiple spawner, presenting a prolonged reproductive period during the whole year, with a peak in the month of April, and is considered as an opportunistic strategist.


2017 ◽  
Vol 29 (1) ◽  
pp. 55-70 ◽  
Author(s):  
VIBHU PRAKASH ◽  
TOBY H. GALLIGAN ◽  
SOUMYA S. CHAKRABORTY ◽  
RUCHI DAVE ◽  
MANDAR D. KULKARNI ◽  
...  

SummaryPopulations of the White-rumped Vulture Gyps bengalensis, Indian Vulture G. indicus and Slender-billed Vulture G. tenuirostris declined rapidly during the mid-1990s all over their ranges in the Indian subcontinent because of poisoning due to veterinary use of the non-steroidal anti-inflammatory drug diclofenac. This paper reports results from the latest in a series of road transect surveys conducted across northern, central, western and north-eastern India since the early 1990s. Results from the seven comparable surveys now available were analysed to estimate recent population trends. Populations of all three species of vulture remained at a low level. The previously rapid decline of White-rumped Vulture has slowed and may have reversed since the ban on veterinary use of diclofenac in India in 2006. A few thousand of this species, possibly up to the low tens of thousands, remained in India in 2015. The population of Indian Vulture continued to decline, though probably at a much slower rate than in the 1990s. This remains the most numerous of the three species in India with about 12,000 individuals in 2015 and a confidence interval ranging from a few thousands to a few tens of thousands. The trend in the rarest species, Slender-billed Vulture, which probably numbers not much more than 1,000 individuals in India, cannot be determined reliably.


Crustaceana ◽  
2014 ◽  
Vol 87 (11-12) ◽  
pp. 1430-1446 ◽  
Author(s):  
Ho Jin Bae ◽  
Chul-Woong Oh

Reproduction and growth of the spiny lebbeid shrimp, Lebbeus groenlandicus (Fabricius, 1775), were investigated based on samples in the East Sea of Korea [= Sea of Japan], from January 2012 to April 2013. We collected 2964 shrimp samples during the study period, which included significantly more females than males (male : female ratio, 1.0 : 1.17). The females were generally larger than the males, and significant differences in the linear-regression slopes of carapace length (CL) versus body weight between the sexes indicate sex-specific differences in allometric growth. The gonadosomatic index (GSI) varied monthly, reaching a maximum in November 2012 (10.28) and a minimum in March 2013 (2.15). The proportion of ovigerous females varied from month to month. The highest values of the GSI coincided with the breeding period, and there was a significant difference between the mean GSI of females with non-eyed and those with eyed eggs, indicating that L. groenlandicus is a consecutive breeder. There was a significant correlation between CL and the number of eggs (EN) in the early egg stages. There was also a significant difference in the slopes of the regressions of CL versus EN between females carrying non-eyed and eyed egg stages. Based on the dry weights in the early egg stages, reproductive output was determined to be 0.18 ± 0.006. The Von Bertalanffy growth function parameters were CL∞ = 38.80 mm, year−1, , and WP = 0.4 for males, and CL∞ = 43.64 mm, year−1, , and WP = 0.6 for females. The growth performance index () was 2.86 for males and 2.89 for females.


2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Fábio Mineo Suzuki ◽  
Diego Azevedo Zoccal Garcia ◽  
Mário Luís Orsi

To study the reproductive dynamics of the mandi-beiçudo, Iheringichthys labrosus, in the Capivara Reservoir, Paranapanema River, Parana, Brazil, specimens were captured trimonthly from March 2001 to July 2004 at four sampling sites. The sex ratio showed a predominance of females in most of months sampled and the larger length classes. The majority of the individuals captured showed a standard length between 16 and 22 cm, with a maximal length of 27.5 cm. The size at first maturity was estimated to be 18.1 and 19.7 cm for females and males, respectively. Analysis of the temporal variation of the gonadosomatic index (GSI) and frequency of occurrence of gonadal maturation stages of males and females for the months sampled showed that I. labrosus reproduces during the whole year, with peak reproduction in November and December. There was a positive correlation between the mean values of GSI and variation in rainfall values, suggesting that this abiotic factor can influence the reproduction of this species. The mean absolute fecundity was 67274.5  16562.5 oocytes, and the mean relative fecundity was 350.6  186.3 oocytes per gram of total weight.


2013 ◽  
Vol 48 (8) ◽  
pp. 1064-1070 ◽  
Author(s):  
Fernanda Keley Silva Pereira Navarro ◽  
Rodrigo Diana Navarro ◽  
Luis David Solis Murgas ◽  
Marina Apocalypse Nogueira Pereira ◽  
Guilherme Crispim Hundley

The objective of this work was to evaluate the effect of photoperiod on luteinizing hormone (LH) plasma levels and gonadal maturation of lambari females. One hundred and twenty adult lambaris, distributed into 12 aquaria of 20 L each, were randomly subjected to three different treatments, in a completely randomized design, and four replicates. Treatments were photoperiods in hours of light (L) and darkness (D): T1, 0 L:24 D; T2, 12 L:12 D; T3, 24 L:0 D. After 40 days, fish were subjected to fasting for 24 hours and, then, anesthetized. Immediately after slaughter, fish were weighed, and their gonads and livers were removed and weighed. Ovaries were weighed and immersed in Bouin's fixative solution for 24 hours and, then, kept in 70% alcohol until processing the material. Subsequently, the oocyte developmental stage was determined. No significant differences were observed between treatments for final weight, ovary weight, gonadosomatic index (GSI), hepatosomatic index (HSI) and LH levels. In all treatments, lambari females showed maturing ovaries with prevalence of vitellogenic oocytes. Photoperiod does not affect the LH levels and ovarian maturation in lambari females.


Sign in / Sign up

Export Citation Format

Share Document