scholarly journals On the reproductive biology of the invasive Armoured Sailfin Catfish Pterygoplicthys pardalis (Castelnau, 1855) (Siluriformes: Loricariidae) from the natural drainages in Thiruvananthapuram, India

2021 ◽  
Vol 13 (9) ◽  
pp. 19263-19273
Author(s):  
Smrithy Raj ◽  
Suvarna Devi ◽  
Amrutha Joy ◽  
A. Biju Kumar

The present paper deals with the breeding biology of the invasive fish Pterygoplicthys pardalis from the natural drainages of Thiruvananthapuram, Kerala. The specimens were collected from Amayizhanchan Thodu, a natural drainage running through the heart of the city. A total of 145 males and 142 females were collected from January to December 2018. The sex ratio was determined monthly as the percentage of males to females (M: F). Monthly mean gonadosomatic index (GSI) values were compared using R stat, and GSI was plotted monthly to identify the spawning seasons. The gonads were examined and different stages of maturity were noted using standard methods. The length at first maturity was also found out. The fish exhibit courtship behaviour and the eggs are deposited in burrows and also along the crevices in the granite walls; the burrows are guarded by the male fish till the young ones are hatched out. The sex ratio showed an average mean value of 1.04: 1 and showed no significant departure. The size at first maturity was 23.9 cm standard length. The ova diameter studies show the presence of ripe ovaries throughout the year, with peaks during March and April and between August and September and in December, indicating the fish is a batch spawner. The absolute fecundity ranges from 923 to 14,777 eggs, and the relative fecundity ranges 0.0142–0.0015. Regression analysis showed a significant relationship (P <0.001) between absolute fecundity and the total length, the total body weight, and ovary weight. The strong breeding behaviour, the presence of accessory respiratory organs, the absence of natural enemies and parental care makes Pterygoplichthys pardalis a successful invader in the natural drainage. More biological studies are needed for the successful eradication of the species from the invaded ecosystem. 

2005 ◽  
Vol 3 (3) ◽  
pp. 433-438 ◽  
Author(s):  
Taís K. Gonçalves ◽  
Marco A. Azevedo ◽  
Luiz R. Malabarba ◽  
Clarice B. Fialho

The reproductive period of Aphyocharax anisitsi is described through the analysis of specimens collected monthly from April 2001 to March 2002 in the arroio do Salso (3022'27"S, 5502'06"W), Rosário do Sul, Rio Grande do Sul, Brazil. The monthly variation of the Gonadosomatic Index mean (GSI) of both males and females allowed the recognition of a defined seasonal reproductive period occurring between September and February, showing a positive correlation with temperature and day-length. Absolute fecundity was 344.8 oocytes and relative fecundity 0.68 oocytes per mg of body weight. Absolute fecundity was correlated with standard length and total body weight. It was possible to identify two categories of males through the analysis of the number of rays bearing hooks on the anal fin: those with few or no rays bearing hooks identified as young males hatched in the last reproductive season, and those with a higher number of anal-fin rays bearing hooks identified as males that had already reproduced once or that are maturing and participating in their first reproductive period. Once developed, anal-fin rays are maintained permanently. A positive correlation was found between the GSI of maturing and mature males and the number of anal-fin rays bearing hooks from August to January. All specimens bearing gill glands were mature or undergoing maturation, and the frequency of occurrence of the gill glands increased with a rise of GSI.


2019 ◽  
Vol 99 (8) ◽  
pp. 1865-1868
Author(s):  
Vanja Čikeš Keč ◽  
Barbara Zorica ◽  
Vedran Vuletin

AbstractAtlantic bonito, Sarda sarda, is one of the representatives of the Scombridae family in the Adriatic Sea. Larvae and juveniles have been found and described in the area, but no information has been published regarding adults spawning in the Adriatic Sea. To explore the strong possibility that Atlantic bonito are reproducing in the Adriatic Sea, 122 specimens of adult Atlantic bonito were collected from a purse seine net ‘palamidara’ over four seasons in 2017. The fork length of the analysed specimens varied from 37.5 to 60.8 cm, with a mean of 48.83 ± 5.59 cm, while total body weight varied between 742.68 and 3102.59 g, with a mean value of 1700.49 ± 543.82 g. Gonadosomatic index values showed an increasing trend from autumn (0.123 for males, 0.897 for females) until spring, while in the summer, they reached their maximum values (3.609 for males, 5.604 for females). This trend was also confirmed by histological and macroscopic analyses of gonads, which suggested that the Atlantic bonito spawning season is in the spring-summer in the Adriatic Sea. Hence, this confirms that this species is spawning in the Adriatic Sea.


2018 ◽  
Vol 6 (5) ◽  
pp. 114-127
Author(s):  
Ebram Luc Gervais ◽  
Soumaïla SYLLA ◽  
Tizié Thierry ZAN-BI ◽  
Boua Célestin ATSE

The reproduction of Liza falcipinnis were investigated in both lagoons (Ebrié and Grand-Lahou) from January 2006 to december 2007. 2162 specimens were examined (914 and 1248 respectively in Ebrié and Grand-Lahou lagoons). Fork length was taken to the nearest 1 mm, and total body weight (TW) and eviscerated body weight (EW) to the nearest 0.1 g. The gonads and the liver were then established removed, weighted to the nearest 0.001g. The reproduced period of Liza falcipinnis was established by analysing the temporal evolution of the frequency of the maturity stages and the monthly variations in the gonadosomatic index (GSI), the hepatosomatic index (HIS) and the condition factor (K). Sex ratio was established taking into account the sex determinations. The size at which 50 % of the specimens became mature (FL50) was estimated. The sex ratio (1:1.24) and (1:1.40) observed respectively in Ebrié and Grand-Lahou lagoons were in favour of females. The first sexual maturity size was 21.0 cm (FL) for males and 27.9 cm (FL) for females in Ebrié lagoon and 24.7 cm (FL) for males and 27.9 cm (FL) for females in Grand-Lahou lagoon. Liza falcipinnis spawns in lagoon and the spawning period ranged from December to April.


Author(s):  
D. Sahoo ◽  
S. Panda ◽  
B.C. Guru

Portunus pelagicus a commercially important crab species found in Chilika lagoon constitutes about 20% of the total crab production. The carapace width (CW) ranges from 4.5–10.5 cm in both the sexes during the study period. The maximum abundance of male was at 6.6 to 7.5 cm CW whereas the females predominate from 6.6 to 9.5 cm CW. The relationship between carapace length (CL) and CW is linear in both sexes which indicates isometric growth. However, the relationship between CL, CW with total body weight (TW) is exponential. The food habit from gut content analysis shows that the species is highly carnivorous and the main food items include prawn carapace and appendages (27.58%), molluscan remaining (21.55%), fish bone (7.75%), seagrass (1.72%), unidentified materials (4.31%) and the mixed food (37.06%). The feeding index was found highest (80.95%) in February whereas it is lowest (60.9%) in June. The mature females are observed from May to July with a peak in July in the lagoon. The highest gonadosomatic index is found in July with an average CW of 10.5 cm. No berried females are found in the study period, which indicates that it did not spawn inside the lagoon and migrates to the sea during the rainy season.


2003 ◽  
Vol 1 (1) ◽  
pp. 61-66 ◽  
Author(s):  
Jacira Silvano ◽  
Cristina L. C. Oliveira ◽  
Clarice B. Fialho ◽  
Hélio C. B. Gurgel

Specimens of Serrapinnus piaba were collected monthly from April 2001 to April 2002 in the rio Ceará Mirim, Rio Grande do Norte State, Brazil. The reproductive period, determined through the monthly variation of the gonadosomatic index (GSI) and maturation stages, occurred from January to April. Non-parametric Spearman test was performed in order to test correlation of monthly GSI variation in males and females with water temperature, rainfall and day length. Rainfall and Temperature were correlated with GSI variation in females only and day length showed a negative correlation with GSI variation of males only. It was verified the presence of hooks on the anal fin of mature and maturing males along all the period of study. The absolute fecundity mean was 441 (±178.08) oocytes, determined by the number of yolky oocytes counted in 27 mature female gonads. The relative fecundity, estimated by the number of yolky oocytes divided by milligram of total body weight was 0.74 (± 0.19).


2015 ◽  
Vol 75 (3 suppl 1) ◽  
pp. 158-167 ◽  
Author(s):  
TMS. Freitas ◽  
BS. Prudente ◽  
VA. Oliveira ◽  
MNC. Oliveira ◽  
EG. Prata ◽  
...  

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.


2019 ◽  
Vol 17 (2) ◽  
Author(s):  
Tiago Magalhães da Silva Freitas ◽  
Luciano Fogaça de Assis Montag

ABSTRACT A field study of the sex ratio, length-weight ratio, body size at first gonadal maturation, and the breeding season of the red-tailed catfish, Phractocephalus hemioliopterus, was carried out in the region of the middle Xingu River in the eastern Amazon basin. The fish were sampled quarterly from September 2012 to January 2014 using gillnets and long lines. The sex ratio was balanced, and while males and females were similar in standard length, the females were heavier than the males, on average. The males presented negative allometric growth, and the females, isometric growth. The estimated size at first maturity was 77.8 cm. The variation in the gonadosomatic index and the greater frequencies of mature specimens indicated a reproductive peak at the beginning of the high-water (flood) period. As P. hemioliopterus is an important commercial fish, our findings will contribute to the future development of effective conservation and management strategies, such as minimum catch size and a close season that is appropriate for the region. These data will also provide important insights for the evaluation of potential impacts on the biology of this fish resulting from the construction of Belo Monte dam.


2010 ◽  
Vol 63 (5-6) ◽  
pp. 349-355
Author(s):  
Mihajlo Jakovljevic ◽  
Slobodan Jankovic ◽  
Natalija Todorovic ◽  
Jasmina Milovanovic ◽  
Snezana Jankovic

Introduction. The aim of our study was to develop and use a population pharmacokinetic model for assessment of individual valproate clearance in children and young adults suffering from epilepsy. Material and methods. The analysis was performed using 52 steady-state concentrations of valproate collected from 26 epileptic patients during the routine clinical practice in our hospital. The mean values of age and total body weight were 19.92 years and 57.12 kg, respectively. NONMEM software with ADVAN 1 subroutine was used for model building and assessing the influence of different covariates. A validation set of 20 epileptic patients (one blood sample per a patient) was used to estimate predicted performances of the pharmacokinetic model. Results. The typical mean value of the clearance of valproate estimated by the base model in our population was 0.377 l/h. Out of five considered covariates (total body weight, age, total daily dose, gender and polytherapy) only the age of the patients was a significant determinant of the clearance of valproate. The final regression model for the clearance of valproate was as following: CL (l/h) = 0.223 + 0.00819


2015 ◽  
Vol 11 (2) ◽  
pp. 43-48
Author(s):  
MAR Joadder

The fecundity and sex- ratio of 2200 Labeo bata (Hamilton) specimens were studied. The fecundity of 234 gravid females varied from 51,354( for a fish with total length of 127.3 mm and total body weight of 20.0 g) to 91,568( for a fish with total length of 256.6 mm and total body weight of 156.70g).The mean fecundity was recorded as 67,617.50±13,510.15 for the average length and weight of 192.98±41.06 mm and 87.79±49.07 g, respectively .The mean total length and weight of gonad was 67.62± 24.01 mm and 20.35±13.50 g, respectively .The relationship between fecundity ( F.) and other parameters such as total length ( TL ), Standard length ( SL),  total weight( TW),  gonadal length (GL),  gonadal weight (GW) and gonadal depth (GD) were studied. DOI: http://dx.doi.org/10.3329/jsf.v11i2.21595 Journal of Science Foundation, 2013;11(2):43-48


2020 ◽  
Vol 67 (1) ◽  
Author(s):  
S.K. Abujam ◽  
S.P. Biswas

Reproductive biology of spiny eel Macrognathus pancalus Hamilton, 1822 was studied from the waterbodies of upper Assam, India. Sexual dimorphism was easily distinguished based on their body shape and colouration. Among the 467 fish samples examined, 312 males and 155 females were identified and the Male:Female (M:F) ratio ranged from 1:0.08 in November to 1:2.17 in June with overall sex ratio of 1:0.5. Five maturity stages were identified in a year and percentage distribution of each stage was calculated. The gonadosomatic index (GSI) ranged from 0.42 to 8.08 for females and from 0.33 to 1.25 for males. The length at 50% of the fishes attained maturity (Lm50) was 9-12 cm in males and at 12-15 cm in females, indicating males matures at moderately smaller size than their female counterparts. Ova diameter ranged from 0.3 to 1.3 mm; absolute fecundity ranged from 765.48 to 1691.96 and relative fecundity from 57.9 to 152.17. M. pancalus spawned once in a year with peak spawning between June and August.


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