scholarly journals Reproductive biology of Rhaphiodon vulpinus (Ostariophysi: Cynodontidae) in the Tocantins River Basin, Brazil

2007 ◽  
Vol 5 (4) ◽  
pp. 479-484 ◽  
Author(s):  
Andréa L. Neuberger ◽  
Elineide E. Marques ◽  
Carlos S. Agostinho ◽  
Rafael J. de Oliveira
Keyword(s):  
River Basin ◽  
Reproductive Biology ◽  
Mean Value ◽  
Reproductive Period ◽  
Total Weight ◽  
Individual Female ◽  
Relative Fecundity ◽  
Mean Diameter ◽  
Tocantins River ◽  
The Individual

In order to evaluate aspects of the reproductive biology of Rhaphiodon vulpinus in the Upper and Middle Tocantins River, samples were taken monthly from October, 1999 through September, 2001, by means of gill nets. Males, which were more abundant than females (chi2 146.87: df=1: p<0.05), matured at a smaller size. The reproductive period of the species extended essentially from November through January, with a peak of activity in November. Fecundity, with an estimated mean value of 98,185 oocytes, varied from 38,177 to 215,841 oocytes, and it did not correlate with the length of the individual female analyzed (r=0.4663: p=0.206). Relative fecundity was 130.6 oocytes/g total weight. Mature oocytes had a mean diameter of 0.98 mm, corresponding to a volume of 0.50 mm³.

scholarly journals Reproductive biology of Bryconamericus iheringii (Ostariophysi: Characidae) from rio Vacacaí, RS, Brazil

2004 ◽  
Vol 2 (4) ◽  
pp. 209-215 ◽  
Author(s):  
Vinicius Renner Lampert ◽  
Marco Aurélio Azevedo ◽  
Clarice Bernhardt Fialho
Keyword(s):  
Southern Hemisphere ◽  
Reproductive Biology ◽  
Reproductive Period ◽  
Total Weight ◽  
Day Length ◽  
Sexually Dimorphic ◽  
Gonadal Maturation ◽  
Relative Fecundity ◽  
Multiple Spawner ◽  
Fin Ray

In this paper we describe some aspects of the reproduction and development of secondary sexual characters of Bryconamericus iheringii, based on the analysis of 194 females and 210 males collected monthly in the rio Vacacaí (30º21'34"S and 54º18'48"W), from April 2001 to March 2002. The reproductive period occurred from September to January (spring and summer in the Southern Hemisphere), as described for other characids of the same area. The absolute fecundity mean was 933.71 ± 303.10 oocytes, and the relative fecundity mean was 0.36 ± 0.08 oocytes per mg of total weight, being the species a multiple spawner. There was no correlation between the values of GSI and variation of biotic (stomach repletion and hepatosomatic indexes) and abiotic data (rainfall, day length and temperature) but we suggest that these factors can influence the reproduction of the species acting as "starters" of the beginning of gonadal maturation. Fin-ray hooks consist in a sexually dimorphic character of the species. Well developed hooks were found mainly in mature males, during the reproductive period and in the largest individuals.

scholarly journals Reproduction of Hypoptopoma inexspectatum (Holmberg, 1893) (Siluriformes, Loricariidae) in the Southern Pantanal Floodplain, Upper Paraguay River Basin, Brazil

2020 ◽  
Author(s):  
M. J. Pereira ◽  
L. F. Viana ◽  
M. H. B. Sais ◽  
Y. R. Súarez
Keyword(s):  
Sex Ratio ◽  
River Basin ◽  
Reproductive Biology ◽  
Standard Length ◽  
Relative Fecundity ◽  
Absolute Fecundity ◽  
Weight Relationship ◽  
Paraguay River

Abstract This work aimed to describe the reproductive biology of Hypoptopoma inexspectatum in southern Pantanal. A total of 538 individuals were sampled and analyzed from February 2009 through January 2011 in southern Pantanal. We did not observe differences in sex-ratio, and both sexes presented positive allometric length/weight relationship (LWR). Reproduction occurs mainly from January to February. Females reached first maturation (L50) with 37.80 mm and males with 45.80 mm. Absolute fecundity is estimated in mean=177.43 (sd±127.06) oocytes and relative fecundity in 3.12 (sd±2.23) oocytes/mg. Fecundity is positively correlated with standard length (Spearman r= 0.43; p=0.013), and total spawning is a used spawning strategy for H. inexspectatum.

scholarly journals Reproductive biology of Leporinus taeniatus Lütken (Pisces, Anostomidae) in Juramento Reservoir, São Francisco River basin, Minas Gerais, Brazil

2005 ◽  
Vol 22 (3) ◽  
pp. 565-570 ◽  
Author(s):  
Ralph G. Thomé ◽  
Nilo Bazzoli ◽  
Elizete Rizzo ◽  
Gilmar B. Santos ◽  
Thiago F. Ratton
Keyword(s):  
River Basin ◽  
Reproductive Biology ◽  
Gonadosomatic Index ◽  
Reproductive Period ◽  
Mature Stage ◽  
Gonad Maturation ◽  
Histological Techniques ◽  
Sao Francisco River ◽  
Fat Consumption ◽  
São Francisco River

The reproductive biology of the piau-jejo Leporinus taeniatus Lütken, 1875, an endemic species from the São Francisco River basin, was studied by using macroscopical and histological techniques. A total of 121 males and 94 females were captured quarterly, between March 2002 and February 2003 in the Juramento Reservoir. Females were larger than males, indicating sexual dimorphism. Stages of gonadal maturation were defined from histological analyses and gonadosomatic index. Peaks of maturing/mature and spawned/spermiated fishes has occurred in period December-February. L. taeniatus presented total spawning and group-synchronic development of the oocytes. The gonadosomatic index accompanied gonad maturation in both sexes, and coelomic fat presented lower levels during maturing/mature stage, indicating fat consumption during the reproductive period. Stomach repletion index presented higher values during spawned and spermiated stages, indicating greater food ingestion after the reproductive period.

scholarly journals Reproductive period, fecundity and histology of gonads of two cheirodontines (Ostariophysi: Characidae) with different reproductive strategies - insemination and external fertilization

2010 ◽  
Vol 8 (2) ◽  
pp. 351-360 ◽  
Author(s):  
Cristina L. C Oliveira ◽  
Clarice B Fialho ◽  
Luiz R Malabarba
Keyword(s):  
Gonadosomatic Index ◽  
Relative Weight ◽  
Gonadal Development ◽  
Reproductive Period ◽  
Total Weight ◽  
Tropical Region ◽  
Temporal Separation ◽  
External Fertilization ◽  
Relative Fecundity ◽  
The Mean

The reproductive period and fecundity of the inseminating cheirodontine Compsura heterura and of the externally fertilizing cheirodontine Odontostilbe pequira, from tropical and subtropical regions of Brazil, respectively, are described. The reproductive period of C. heterura lasted from January to April 2002, while O. pequira showed two reproductive periods, the first during September and October 2001 (spring), and the second between January and February 2002 (summer). Smaller classes of SL of females of O. pequira predominated in the second reproductive period, suggesting individuals born in the first period become shortly sexually mature, participating in the second reproductive period. In C. heterura, from a tropical region, temperature showed significant correlations with the variation in the gonadosomatic index (GSI) for both sexes, and rainfall showed significant correlation with the variation in the GSI only for females. In O. pequira, from a subtropical region, photoperiod was the only factor that showed significant correlations with the GSI variation in both sexes. The mean relative fecundity of C. heterura was 0.55 oocytes per milligram of total weight, similar to that of other cheirodontines with external fertilization, refuting the hypothesis, at least in Cheirodontinae, that insemination provides diminishing energy expenditure for the production of oocytes, due to a greater probability of fertilization. The mean relative fecundity of O. pequira was 0.8 oocytes per milligram of total weight, the largest known among cheirodontines. Spermatozoa were found inside the ovaries of maturating, mature and semi-spent females of C. heterura supporting the hypothesis of temporal separation between courtship and spawning. The largest relative weight of testis and the presence of sperm in maturing ovaries outside the reproductive period in C. heterura support the hypothesis that males of inseminating species make a greater investment in gonadal development than those externally fertilized.

scholarly journals Reproductive Biology of the Mola Carplet Amblypharyngodon mola (Hamilton) (Cypriniformes: Cyprinidae) from Netrakona Water

1970 ◽  
Vol 44 (3) ◽  
pp. 377-379 ◽  
Author(s):  
Bimal Kanta Saha ◽  
M Rafiqul Islam ◽  
Aparna Saha ◽  
M Altaf Hossain
Keyword(s):  
Sex Ratio ◽  
Key Words ◽  
Reproductive Biology ◽  
Standard Length ◽  
Mean Value ◽  
Total Weight ◽  
Total Length ◽  
The Mean

Some aspects of the reproductive biology viz. sex ratio, fecundity and reproductive periodicity of Amblypharyngodon mola were studied during March 2004 through February 2005 in Netrakona. Sex ratio was found to be 1:2.03. Fecundity varied from 1,291 to 12,797 with a mean value 5,751.46 ± 3,321.73 eggs. The relationships between Fecundity (F) and Total Length (TL), Standard Length (SL), Total Weight (TW), Gonadal length (GL) and Gonadal Weight (GW) were calculated and found to be highly significant. The mean of ova diameter was 1.4 ± 0.35mm. Different methods used to study the reproductive periodicity showed that the periodicity of A. mola starts from March and continues up to August with a peak in May. Key words: Reproductive biology, Reproductive periodicity, Amblypharyngodon mola. DOI: 10.3329/bjsir.v44i3.4414 Bangladesh J. Sci. Ind. Res. 44(3), 377-379, 2009   

LBA-ECO LC-04 MACROHYDROLOGICAL ROUTING DATA FOR THE AMAZON AND TOCANTINS RIVER BASIN

2011 ◽  
Author(s):  
R.G. ANDRADE, ◽  
T.R. BUSTAMANTE, ◽  
M.T. COE, ◽  
M.H. COSTA, ◽  
C.H.C. OLIVEIRA, ◽  
...  
Keyword(s):  
River Basin ◽  
Tocantins River

SERUM THYROTROPHIN AND THE RESPONSE TO THYROTROPHIN RELEASING HORMONE IN SYMPTOMLESS AUTOIMMUNE THYROIDITIS AND IN BORDERLINE AND OVERT HYPOTHYROIDISM

1974 ◽  
Vol 75 (2) ◽  
pp. 274-285 ◽  
Author(s):  
A. Gordin ◽  
P. Saarinen ◽  
R. Pelkonen ◽  
B.-A. Lamberg
Keyword(s):  
Autoimmune Thyroiditis ◽  
Elevated Serum ◽  
Mean Value ◽  
Primary Hypothyroidism ◽  
Overt Hypothyroidism ◽  
Thyrotrophin Releasing Hormone ◽  
Releasing Hormone ◽  
The Mean ◽  
The Individual ◽  
Serum Tsh

ABSTRACT Serum thyrotrophin (TSH) was determined by the double-antibody radioimmunoassay in 58 patients with primary hypothyroidism and was found to be elevated in all but 2 patients, one of whom had overt and one clinically borderline hypothyroidism. Six (29%) out of 21 subjects with symptomless autoimmune thyroiditis (SAT) had an elevated serum TSH level. There was little correlation between the severity of the disease and the serum TSH values in individual cases. However, the mean serum TSH value in overt hypothyroidism (93.4 μU/ml) was significantly higher than the mean value both in clinically borderline hypothyroidism (34.4 μU/ml) and in SAT (8.8 μU/ml). The response to the thyrotrophin-releasing hormone (TRH) was increased in all 39 patients with overt or borderline hypothyroidism and in 9 (43 %) of the 21 subjects with SAT. The individual TRH response in these two groups showed a marked overlap, but the mean response was significantly higher in overt (149.5 μU/ml) or clinically borderline hypothyroidism (99.9 μU/ml) than in SAT (35.3 μU/ml). Thus a normal basal TSH level in connection with a normal response to TRH excludes primary hypothyroidism, but nevertheless not all patients with elevated TSH values or increased responses to TRH are clinically hypothyroid.

Sorption of pesticides used in banana production on soils of Ecuador

Soil Research ◽  
2002 ◽  
Vol 40 (7) ◽  
pp. 1085 ◽  
Author(s):  
Tanya Cáceres ◽  
Guang-Guo Ying ◽  
Rai Kookana
Keyword(s):  
River Basin ◽  
Ecosystem Health ◽  
Production Systems ◽  
Parent Compound ◽  
Mean Value ◽  
Organic Carbon Content ◽  
Banana Production ◽  
Kd Values ◽  
Production Area ◽  
Impact Of Pesticides

There is concern about the migration and adverse impact of pesticides used in banana production systems in Ecuador on aquaculture and ecosystem health. Therefore, we studied the sorption of chlorothalonil, fenamiphos, and its 2 metabolites (fenamiphos sulfone and fenamiphos sulfoxide), by batch method on 6 surface soils from the Guayas River Basin (1–3�S, 79–81�W), a major banana production area of Ecuador. The sorption of chlorothalonil on the 6 soils was high and varied considerably as shown by the Kd values ranging from 68.50 to 152.60 L/kg. The sorption coefficients normalised with the organic carbon content of soil (Koc) for chlorothalonil ranged from 2330 to 7336 kg/L, with a mean value of 4012 kg/L. These Koc values are higher than those previously reported in the literature. The sorption of fenamiphos and its metabolites to the 6 soils varied among soils in a similar pattern. The Kd values ranged from 5.66 to 14.31�L/kg for fenamiphos, from 2.81 to 8.79 L/kg for fenamiphos sulfone, and from 0.77 to 4.00 L/kg for fenamiphos sulfoxide, respectively. In all of the soils the sorption coefficients of both metabolites of fenamiphos were lower than that for the parent compound. The Koc values ranged from 220 to 515 kg/L (mean value 371 kg/L) for fenamiphos, from 29 to 141 kg/L (mean value of 76 kg/L) for fenamiphos sulfoxide, and from 79 to 334 kg/L (mean value of 191 kg/L) for fenamiphos sulfone. Chlorothalonil had much stronger sorption than fenamiphos and its metabolites on the Ecuadorian soil. Due to lower sorption and therefore greater mobility and longer persistence of the fenamiphos metabolites, these compounds need adequate consideration during residue monitoring and assessment of potential off-site impacts on ecosystem health and aquaculture in the Guayas River Basin.

scholarly journals Reproductive Biology of Round Sardinella (Sardinella Aurita) (Valenciennes, 1847) in Senegalese Coastal Waters

2018 ◽  
Vol 9 (1) ◽  
pp. 31
Author(s):  
Ismaïla NDIAYE ◽  
Alassane SARR ◽  
Alioune FAYE ◽  
Modou THIAW ◽  
Malick DIOUF ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Reproductive Biology ◽  
Coastal Waters ◽  
Sexual Maturity ◽  
Reproductive Parameters ◽  
Monthly Variation ◽  
Relative Fecundity ◽  
The Mean ◽  
Sardinella Aurita ◽  
Somatic Index

In this study, a total of 1068 specimens Sardinella aurita of which 553 females and 515 males were examined. The objectif of this study was to determine the reproductive parameters of Sardinella aurita. The sex ratio was significantly in favor of females (55%). The size at first sexual maturity was estimated at 18.9 cm for females and 18.0 cm for males. The monthly variation of sexual maturity stages and gonado-somatic index (GSI) allowed to locate the reproduction periods from February to June and from September to December. The mean absolute fecundity was estimated at 110.794 ± 7582 oocytes whereas relative fecundity was about 422 ± 26 oocytes per gram of female.

scholarly journals Reproductive biology of Artibeus fimbriatus Gray 1838 (Chiroptera) at the southern limit of its geographic range

2016 ◽  
Vol 16 (4) ◽  
Author(s):  
Camila S. Lima ◽  
Marta Elena Fabián
Keyword(s):  
Reproductive Biology ◽  
High Temperatures ◽  
Rainy Season ◽  
Regional Climate ◽  
Geographic Range ◽  
Reproductive Period ◽  
Southern Limit ◽  
Reproductive Patterns ◽  
Pregnant Females

Abstract Bats of the Phyllostomidae family exhibit different reproductive patterns in Neotropical regions and the strategy adopted depends on the regional climate. Here we studied the reproductive biology of Artibeus fimbriatus at the southern limit of their distribution in Brazil. This region has no rainy season, and the climate is characterized by high temperatures and variable photoperiods. We examined 129 A. fimbriatus females over several months, and used histological procedures where necessary in order to determine whether bats were pregnant. Females exhibited a long reproductive period and were pregnant from June until February. The reproduction events were found to be dependent on the photoperiod, but independent of annual accumulated precipitation. Our results show that at the southern limit of their distribution, A. fimbriatus exhibit seasonal-dependent reproductive patterns, with parturition events occurring during spring and summer, in which the days are longer and temperature is warmer.

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