scholarly journals Reproductive patterns of bogue, Boops boops (Sparidae), in the southeastern Adriatic Sea

2017 ◽  
Vol 58 (1) ◽  
pp. 117-125
Author(s):  
Tatjana Dobroslavić ◽  
Renata Mozara ◽  
Branko Glamuzina ◽  
Vlasta Bartulović
Keyword(s):  
Total Population ◽  
Adriatic Sea ◽  
Condition Factor ◽  
Gonadosomatic Index ◽  
Gonad Development ◽  
Size Class ◽  
Oocyte Diameter ◽  
Allometric Growth ◽  
Monthly Distribution ◽  
Boops Boops

The reproductive characteristics of bogue (Boops boops) in the southeastern Adriatic Sea are presented in this study. The analysis is based on 676 specimens caught by seine net from December 2011 to November 2012. Total length of females ranged from 13.3 to 29.3 cm and males from 15.1 to 26.3 cm. The overall sex ratio of females to males was 1:0.85 (χ2=4.314; P < 0.05) with a slightly higher number of females in the largest size class. Length-weight relationship for the total population indicated negative allometric growth (b=2.911). Values of the condition factor are relatively low for both sexes. Maximum values were recorded in September 1.025 for females and 1.029 for males. Gonadosomatic index and histological examination showed that the spawning season of the bogue in the Adriatic is from January to May with peak in February. Six stages of gonad development were identified: immature, undergoing maturation, ripening, ripe, spawning and spent. The monthly distribution of the different sexual maturity stages and the frequency distribution of oocyte diameter revealed that this species is a batch spawner.

scholarly journals Length-weight relation, condition factor and gonadosomatic index of the whitemouth croaker, Micropogonias furnieri (Desmarest, 1823) (Actinopterygii: Sciaenidae), caught in Lençóis Bay, state of Maranhão, eastern Amazon, Brazil

2017 ◽  
Vol 65 (1) ◽  
pp. 1-8 ◽  
Author(s):  
James Werllen de Jesus Azevedo ◽  
Antonio Carlos Leal de Castro ◽  
Marcelo Henrique Lopes Silva
Keyword(s):  
Sex Ratio ◽  
Rainy Season ◽  
Condition Factor ◽  
Gonadosomatic Index ◽  
Length Distribution ◽  
The State ◽  
Allometric Growth ◽  
First Semester ◽  
Length Relationship ◽  
Micropogonias Furnieri

Abstract The whitemouth croaker, Micropogonias furnieri, which is exploited off the state of Maranhão, Brazil, reinforces the need for maintenance programs of natural stocks of this species to assist in the management of this exploited resource. The aim of the present study was to describe aspects regarding its reproductive characteristics (gonadosomatic index and condition factor) and also the length distribution and weight-length relationships. The fish were caught in Lençóis Bay in the state of Maranhão (eastern Amazon) between June 2010 and July 2011. A total of 570 individuals were caught (318 males and 252 females). Differences in length were found between the sexes, with females larger than males. The sex ratio indicated a tendency for females to be more abundant in the rainy season (first semester), whereas males predominated in the dry season (second semester). The weight-length relationship indicated negative allometric growth for both sexes. The analysis of the variation in the condition factor suggests that lower values coincided with higher gonadosomatic index values and that this factor is a good reproductive indicator for M. furnieri in the region.

scholarly journals Influence of the flood pulse on the reproduction of Tocantinsia piresi (Miranda Ribeiro) and Auchenipterus nuchalis (Spix & Agassiz) (Auchenipteridae) of the middle Xingu River, Brazil

2015 ◽  
Vol 75 (3 suppl 1) ◽  
pp. 158-167 ◽  
Author(s):  
TMS. Freitas ◽  
BS. Prudente ◽  
VA. Oliveira ◽  
MNC. Oliveira ◽  
EG. Prata ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Condition Factor ◽  
Gonadosomatic Index ◽  
Flood Pulse ◽  
Allometric Growth ◽  
Xingu River ◽  
Ratio Size ◽  
Flood Period ◽  
First Maturity ◽  
Size At First Maturity

Abstract This study investigates the influence of the flood pulse on the reproductive biology of the auchenipterids Tocantisia piresi (Miranda Ribeiro, 1920) and Auchenipterus nuchalis (Spix & Agassiz, 1829) from the middle Xingu River in the Brazilian state of Pará. The specimens were collected every three months between April, 2012, and January, 2014, covering four distinct periods (flood, ebb, dry, and filling). The sex ratio, size at first maturity, gonadosomatic index, and condition factor were analysed in the two species, and evaluated in the context of the different hydrological periods. A total of 897 specimens of T. piresi were collected, of which 467 were female, and 430 males, and 383 A. nuchalis (286 females and 97 males). In T. piresi, the sex ratio was biased only in the filling and ebb periods, whereas in A. nuchalis, it departed significantly from the expected ratio of 1:1 in all periods, with a predominance of females. The female T. piresi mature at a smaller size than the males, with the opposite of the pattern being recorded in A. nuchalis. In T. piresi, the breeding peak was observed during the low water periods, whereas in A. nuchalis, the peak was recorded in the flood periods. Male and female T. piresi presented similar positively allometric growth rates, whereas in A. nuchalis, growth was negatively allometric, but rates were different between genders. A higher condition factor was recorded in the females of both species during the ebb period. Overall, the results of this study reveals distinct flood pulse effects on the reproductive parameters of the two auchenipterid species studied; for A. nuchalis the spawning seems to happen at the flood period and for T. piresi at the dry season of the middle Xingu River.

scholarly journals The length-weight relationship, condition factor and reproductive biology of Pseudotolithus (p) senegalensis (valenciennes, 1833) (croakers), in Tombo western rural district of Sierra Leone

2014 ◽  
Vol 14 (66) ◽  
pp. 9376-9389
Author(s):  
JO Olapade ◽  
◽  
S Tarawallie
Keyword(s):  
Sex Ratio ◽  
Sierra Leone ◽  
Reproductive Biology ◽  
Condition Factor ◽  
Gonadosomatic Index ◽  
Hepatosomatic Index ◽  
Allometric Growth ◽  
Spawning Period ◽  
Weight Relationship ◽  
Spawning Behaviour

The length – weight relationship (LWR), condition factor (K), sex ratio, gonadosomatic index (G S I) and hepatosomatic index (H S I) of 412 specimens of Pseudotolithu s s enegalensis (Valenciennes, 1833) from Tombo , a coastal fishing community in the western rural district of Sierra Leone were studied for twelve months . Samples used for the study were collected from the catches of artisanal fishers and measurement s of length and weight of samples were done in situ using the facilities of the Ministry of Fisheries and Marine Resources. Samples for the reproductive study were preserved in an ice box and taken to the laboratory of the Department of Aquaculture and Fisheries Management, Njala University , Sierra Leone for analysis. The parameters "a" and "b" of the length - weight relationship were estimated using the equation described by Ricker ( W = aL b ) while the condition factor was calculated using Fulton`s equation (K = W1 00 / L 3 ) . The reproductive biology of the fish was estimated using Gonadosomatic index ( GSI ) and Hepatosomatic index ( H S I ) . The combined LWR for both sexes showed that a, b and r values were – 2.57 , 3. 3 5 and 0. 899 , respectively. The r – values obtained show a strong linear relationship between the length and weight of the species. The length - weight relationship indicated allometric growth for P . senegalensis in the study area. The condition factor (K) varied from 0.64 – 1.0 ; this may be attributed to environmental conditions of the water . The species clearly exhibited a positive allometric growth pattern ( tα ( 2) , 0.05, 411 > 1.965) . The sex ratio of males to females was 1:1. 15 and was not significantly different from the expected 1:1 ratio. Estimation of GSI and HSI was carried out from December, 2010 to May, 2011 to determine the spawning behaviour of P. senegalensis . The mean GSI obtained indicate d that March and April , respectively are the two peak spawning period for the species . Gonado somatic index ranged between 1.1 % and 2.8% for the females. The results of this study revealed that P. senegalensis doe s not have obligatory spawning month but exhibit multiple spawning behaviour. T he length - w eight relationships and condition factor of the study indicated that the fish were thriving very well in the coastal water of Sierra Leone. Sustainable management of the species , therefore , require s that the environment be protected against anthropogenic pollution and imposition of closed fishing season especially during the t wo peak spawning period is recommended to enable the species recruit effectively.

Sardine (Sardina pilchardus) spawning in the light of fat content analysis

2019 ◽  
Vol 83 (3) ◽  
pp. 207
Author(s):  
Barbara Zorica ◽  
Ivana Anđelić ◽  
Vanja Čikeš Keč
Keyword(s):  
Content Analysis ◽  
Body Length ◽  
Reproductive Cycle ◽  
Adriatic Sea ◽  
Gonadosomatic Index ◽  
Total Body Length ◽  
Fat Content ◽  
Sardina Pilchardus ◽  
Allometric Growth ◽  
Total Body

Sardine samples from commercial catches obtained by purse seiners operating in Croatian fishing grounds (eastern Adriatic Sea) were collected monthly from March 2017 to February 2018 (excluding January due to a fishing ban). A total of 1085 sardines were analysed. Their total body length and mass ranged from 11.5 to 16.9 cm (mean±SD: 13.9±0.03 cm) and from 11.30 to 54.03 g (mean±SD: 20.31±0.161 g), respectively. Analysis of the length-mass relationship showed positive allometric growth (b=3.3573, r=0.948). Female specimens were predominant (m/f=0.404). According to the monthly gonadosomatic index values, spawning occurred from November to February, which was consistent with previous investigations. The monthly analysis of fat content in the gonads, liver and muscles indicated that the fat content in each studied tissue oscillated seasonally regardless of sex. These alternations were linked to the sardine’s reproductive cycle.

scholarly journals Reproductive tactics used by the Lambari Astyanax aff. fasciatus in three water supply reservoirs in the same geographic region of the upper Iguaçu River

2010 ◽  
Vol 8 (4) ◽  
pp. 885-892 ◽  
Author(s):  
Juliano Pilotto Abelardino da Silva ◽  
Adriane Esquivel Muelbert ◽  
Elton Celton de Oliveira ◽  
Luís Fernando Fávaro
Keyword(s):  
Sex Ratio ◽  
Condition Factor ◽  
Gonadosomatic Index ◽  
Geographic Region ◽  
The Other ◽  
Allometric Growth ◽  
Reproductive Tactics ◽  
Average Value ◽  
Water Supply Reservoirs ◽  
Iguaçu River

The species Astyanax aff. fasciatus was investigated as regards differences in reproductive tactics in three reservoirs with different ages (Iraí, Piraquara and Passaúna) located in the same geographic region. The biological material was obtained through monthly collections carried out from july/2006 to june/2007. The average value of the gonadosomatic index (GSI) in Passaúna reservoir was significantly higher in relation to the values obtained in the other reservoirs. Spawning was total in Iraí reservoir and partial in the others. Allometric growth of the species was negative in Iraí reservoir and positive in the others. The highest condition factor value was estimated in Iraí reservoir, followed by Piraquara and Passaúna reservoirs, respectively. Females predominated in all of the reservoirs during the study period. The sex ratio per length class showed, for the three reservoirs, the predominance of males in the smaller length classes. These results verified that the species uses distinct reproductive tactics in the analyzed reservoirs and that these tactics seem to reflect the degree of stabilization of each environment.

scholarly journals Population structure and reproductive biology of Loricariichthys melanocheilus Reis & Pereira, 2000 (Siluriformes: Loricariidae) in the rio Ibicuí, Brazil

2015 ◽  
Vol 13 (2) ◽  
pp. 371-382 ◽  
Author(s):  
Éverton Luís Zardo ◽  
Everton Rodolfo Behr
Keyword(s):  
Population Structure ◽  
Sex Ratio ◽  
Reproductive Biology ◽  
Condition Factor ◽  
Gonadosomatic Index ◽  
Maturity Stage ◽  
Allometric Growth ◽  
Males And Females ◽  
Lotic Environments ◽  
Gonadal Condition

The objective of this study was to analyze population structure (spatial distribution, seasonal distribution and distribution by length classes, sex ratio and length-weight relationship) and aspects of the reproductive biology of Loricariichthys melanocheilus. Fish were sampled bimonthly using gillnets and trammel nets in lentic and lotic environments in the rio Ibicuí, between the years 2000 and 2001. Were collected 410 specimens: 230 females, 164 males and 16 specimens whose sex could not be determined. A greater number of specimens were collected in October/November and December/January and in lentic environments. The greater length classes had a higher amount of females (p < 0.05) and the sex ratio in all sampling periods was 1.38 females per male. Both males and females showed positive allometric growth (b = 3.299 and b =3.487, respectively). The highest values for gonadosomatic index (GSI) and gonadal condition factor (K) were observed from August/September and peaked in October/November, just like the highest frequencies of females at maturity stage C (mature), which is indicative that the breeding season occurs at this time.

scholarly journals Effect of photoperiod on ovarian maturation in Cheirodon interruptus (Teleostei: Characidae)

2019 ◽  
Vol 79 (4) ◽  
pp. 669-677 ◽  
Author(s):  
I. D. García ◽  
S. E. Plaul ◽  
D. Torres ◽  
P. S. Del Fresno ◽  
L. A. Miranda ◽  
...  
Keyword(s):  
Condition Factor ◽  
Wild Population ◽  
Gonadosomatic Index ◽  
Vitellogenic Oocyte ◽  
Oocyte Diameter ◽  
Ovarian Maturation ◽  
Pampean Region ◽  
Spring Transition ◽  
Plasma Estradiol ◽  
Photoperiodic Regime

Abstract Cheirodon interruptus is a ubiquitous small characid that inhabits the Pampean region and commonly used as bait. Its vast market is supplied from the wild population causing a significant environmental impact. In this study, we assess the effect of photoperiod on ovarian maturation in order to evaluate its potential as a tool to manipulate reproduction under artificial conditions. Four treatments in triplicate (light: dark, L: D) were tested: 24L: 0D, 12L: 12D, 0L: 24D and a progressive photoperiod corresponding to the daily photoperiod increments in wild during winter-spring transition, accelerated three times. The experiment was conducted for 45 days. Gonadosomatic index (GSI), oocyte mean diameter, vitellogenic oocyte proportions, plasma estradiol concentrations (E2), condition factor (Kn) and standard length were estimated. Values of mean GSI, oocyte diameter, vitellogenic oocyte proportions and E2 concentration were maximum in the progressive treatment indicating vitellogenesis stimulation. In turn the same parameters were minimum in the 24L: 0D, revealing the vitellogenesis inhibition. This study showed that photoperiodic regime play an important role in the onset of ovarian maturation in C. interruptus.

scholarly journals Ecología trófica y reproductiva de Hemibrycon sierraensis (Characiformes: Characidae) pez endémico del río Gaira, Sierra Nevada de Santa Marta, Colombia

2017 ◽  
Vol 65 (3) ◽  
pp. 1033
Author(s):  
Eduardo J. Ibarra-Trujillo ◽  
Carlos A. García-Alzate
Keyword(s):  
Sierra Nevada ◽  
Sexual Maturity ◽  
Condition Factor ◽  
Feeding Habits ◽  
Gonadosomatic Index ◽  
Stomach Contents ◽  
Trophic Niche ◽  
Oocyte Diameter ◽  
Frequency Of Occurrence ◽  
Average Size

The study of feeding habits in fishes can give important information about their role in the fish community, their functional role in the ecosystem, and their relationships with all available resources. We studied H. sierraensis from Gaira River and performed eight bi-monthly samples between May 2014 and November 2015. We analyzed fish stomach contents by the numerical (% N), volume (% V) and frequency of occurrence (% FO) methods; we also calculated the index of food importance (IA), coefficient of emptiness (CV), trophic niche breadth (used H ') and condition factor (K). Additionally, we determined the sex ratio, gonadosomatic index (RGS), fecundity, minimum and average size at sexual maturity, and oocyte diameter by standard methods. The Gaira River has irregular meanders with clear waters, and high current velocity through its drainage; it is generally oligotrophic, with a tendency to eutrophic condition in some places. Observed dissolved oxygen values were high (5.4 mg/L), electrical conductivity was 68.63 µS/cm, and pH was found neutral. We analyzed stomach contents of 477 specimens, and found a 1.59 % coefficient of vacuity. The species was found euryphagic in its feeding habits (H'= 0.69), omnivorous tending to insectivorous; its diet consisted mainly of Trichoptera larvae (Atanatolica sp.), followed in importance by snails (Gastropoda Pomacea sp.) and dipteran larvae such as Simulium sp. Significant differences in both frequency of occurrence and the volume consumed were observed for the different size classes, as well as between different seasons of the year. The condition factor indicated that the species was well fed. Sex was determined for 424 fish, of which 241 were male and 181 female, given a ratio of 1.3: 1 (male-female) which resulted significantly different (Chi 2: 16.14; P= 0.02). The gonadosomatic index indicated that reproduction occurs during the high water river phase, fecundity was high, and oocyte diameter was relatively small. Males reached sexual maturity at an average size of 67.08 mm SL, and females at 70.68 mm SL. Their life history strategy is seasonal r. Management and conservation plans for this species are required due to human intervention in their habitat, originated by the growing tourist activity in the area.

IMPLANTATION OF LHRH-a HORMONE TO STIMULATION OF GONAD DEVELOPMENT OF HUMPBACK GROUPER SECOND GENERATION ( F-2 )

2013 ◽  
Vol 5 (2) ◽  
Author(s):  
Tridjoko Tridjoko
Keyword(s):  
Body Weight ◽  
Second Generation ◽  
Gonad Development ◽  
Gonadal Development ◽  
Oocyte Diameter ◽  
2Nd Generation ◽  
Length Range ◽  
Concrete Tank ◽  
Implant Treatment ◽  
Stimulation Of

This study aimed to determine the effect of LHRH-a hormone implantation on gonadal development of humpback grouper, Cromileptes altivelis 2nd generation (F-2). Individuals used were 20 female grouper fish with weight range of 600-800 gram/fish and total length range of 28.0-30.0 cm. The treatment used 5 fish each with tagging. Grouper fishes were stocked into the 75 m3 circular concrete tank. Hormone of LHRH-a with dosage of 50 μg/kg body weight was used as implant treatment of (A) 1 time,, (B) 2 times, (C) 3 times, and (D) without implant. The results showed that implantation of LHRH-a hormone were significantly stimulate gonad development of humpback grouper second generation (F-2). Treatment of 3 times implant every month showed the best results produced  oocyte diameter up to 480 μm, while the control of oocyte diameter only reached <400 μm. Keywords: LHRH-a hormone, implantation, Humpback grouper, gonad development

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