scholarly journals TASA DE PRODUCCIÓN DE HUEVOS DE COPÉPODOS DEL PACÍFICO CENTRAL MEXICANO

2016 ◽  
Vol 31 (1) ◽  
pp. 1
Author(s):  
Sergio Herandez -Trujillo ◽  
Gabriela Ma. Esqueda Escárcega

Se estimó la producción de huevos en aguas mexicanas del Pacífico tropical oriental mediante indicadores en copépodos pelágicos bajo condiciones de laboratorio. Los copépodos fueron recolectados durante abril de 2015, separados e incubados en tres estaciones oceanográficas frente a las costas de Guerrero, México. Solo Labidocera acutifrons, Subeucalanus pileatus y Centropages furcatus presentaron actividad reproductora. Los indicadores de producción secundaria fueron la tasa de producción de huevos (TPH), la relación masa-longitud y el factor de condición. La especie con mayor TPH y el valor más alto de factor de condición (K) fue L. acutifrons. En las tres especies se observó un crecimiento de tipo alométrico. Esta es la primera estimación de producción secundaria de zooplancton en el Pacífico Central de México, por lo que debe ampliarse a un mayor número de taxa y a una escala temporal-espacial estacional mayor. Copepod egg production rate in pelagic copepods in the Mexican Central Pacific Estimates of secondary production through indicators from pelagic copepods under laboratory conditions were carried out in Mexican waters of the eastern tropical Pacific. Copepods were collected during April 2015, separated and in three oceanographic stations off the coast of Guerrero, Mexico. Only Labidocera acutifrons, Subeucalanus pileatus and Centropages furcatus presented reproductive activity. Secondary production indicators were the rate of egg production (TPH), the mass-length relationship and condition factor. The species with the highest TPH and the highest value of condition factor (K) was Labidocera acutifrons. In all three species allometric growth was observed. This is the first estimate of secondary production for zooplankton in the Mexican Central Pacific. Thus it should be extended to a larger number of taxa and for a wider seasonal space-time scale

2021 ◽  
Vol 29 (2) ◽  
pp. 100-107
Author(s):  
Serdar Yedier ◽  
Derya Bostanci ◽  
Nazmi Polat

Abstract The aim of the current study was to determine the length-weight relationship (LWR) and length-length relationship (LLR) with condition factor (K) values for Oxynoemacheilus angorae from the Perşembe Plateau meandering streams in Ordu, Turkey. A total of 65 fish specimens, which were caught with electrofishing gear, were examined. Fish standard length (SL), fork length (FL), total length (TL), and body weight (W) were determined. There were no statistical differences between the measurements of male and female O. angorae specimens; therefore, the female and male specimens were evaluated together in the current study. The LWR equation and determination coefficient of O. angorae were W = 0.014 TL2.7359 (r2 = 0.9659). The 95% confidence interval of the b value for the O. angorae specimens from the Perşembe Plateau meandering streams was 2.7261 to 2.7435. In the present study, it was determined that O. angorae specimens showed negative allometric growth. Calculations of O. angorae TL-SL, TL-FL, and FL-SL relationship equations and determination coefficients were as follows: TL = 0.2091+1.1646 SL, (r2 = 0.986); TL = 0.1341+1.0301 FL (r2 = 0.9914); and FL = 0.0998+1.1261 SL, (r2 = 0.9868), respectively. A new maximum total length was recorded for O. angorae in this study. The average condition factor value of O. angorae was 0.9954. This value could have indicated that this species was encountering some problems in this habitat. The O. angorae parameters determined were the first data reported for the Perşembe Plateau meandering streams in Ordu, Turkey (Middle Black Sea Region).


2017 ◽  
Vol 65 (1) ◽  
pp. 1-8 ◽  
Author(s):  
James Werllen de Jesus Azevedo ◽  
Antonio Carlos Leal de Castro ◽  
Marcelo Henrique Lopes Silva

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.


2018 ◽  
Vol 11 (41-42) ◽  
Author(s):  
Madeline Getzemani Molina-Ortega ◽  
Horacio Vázquez-López

The growth of organisms is accompanied by changes in proportion and size, and it is known as relative or allometric growth. C. crassum is one of the largest crab species it inhabits mangrove forests in the Eastern tropical Pacific, however, the data of this specie is deficient and limited to a few records. Therefore, the aim of this work was to estimate the growth of C. crassum in El Salado stream, Puerto Vallarta, Jalisco, Mexico. A total of 252 organisms were captured in the rainy season, which were marked and released after assessments. The Huxley equation was used to determine allometry and to estimate the condition factor (K) and the growth rate. The sex ratio was 1:1.72, favoring females. The range of the condition factor in females was between 0.02 and 0.06 g/cm3. In ovigerous females the K mínimum value was 0.03 and the maximum value was 0.08 g/cm3; for males the K minimum was 0.03 and the maximum was 0.14 g/cm3. A K=0.88 was obtained and Lmax=95.1 mm. There were no significant differences in CA between sexes, neither in PO. While differences could be observed in LQ and AQ between sexes. It was concluded that C. crassum growth is similar to another gecarcinid species in El Salado. Males reach larger sizes than females and the condition factor is similar between males and non-ovigerous females, but there are significant differences between the condition factor in females and ovigerous females.<br /><br />


2019 ◽  
Vol 40 (2) ◽  
pp. 172-175
Author(s):  
Argiro Ramírez ◽  
Jorge Paramo

Abstract We determined size structure, sex ratio, and condition factor for the pink shrimp, Penaeus notialisPérez Farfante, 1967 in the Caribbean coast of Colombia, information essential for the design of management and conservation strategies to ensure a sustainable fishery. Total length (TL; ± 0.01 mm) ranged from 79.47 to 192.80 mm TL (mean 148.21 ± 17.75) for females and 79.00–181.83 mm TL (mean 122.52 mm ± 12.55) for males. Statistically significant differences (P &lt; 0.01) in size and weight (± 0.1 mg) between sexes were found year-round; males were smaller and weighed less than females. The sex ratio showed significant differences (P &lt; 0.01) between the total number of females and males per total length class when compared with a 50% sex ratio. The monthly sex ratio showed significant differences between the number of females and males. The weight-length relationship showed positive allometric growth (b = 3.118) for females, whereas negative allometric growth (b = 2.663) was observed for males. The condition factor (K) ranged 0.0002–0.0023 (mean 0.0009 ± 0.0007) for females and 0.0005–0.2179 (mean 0.0316 ± 0.0642) for males.


2021 ◽  
Vol 9 (1) ◽  
pp. 104-110
Author(s):  
Amadou GUISSE ◽  
Guillaume KOUSSOVI ◽  
Farokh NIASS

The weight-length relationship and the condition factors are fundamental parameters with several uses in biology, fish ecology and fisheries management. Thus, in the Special Wildlife Reserve of Gueumbeul (SWRG) in Senegal, the weight-length relationship and condition factor were established for Mugil cephalus (Linnaeus 1758). A total of 311 individuals (97 females and 214 males) of M. cephalus were collected by the artisanal fishery using cast nets. The total length and weight ranged from 11.1 to 25 cm and 15.9 to 145.26 g, respectively. The results showed that in the SWRG, both in females (b = 2.60) and males (b = 2.899), M. cephalus had negative allometric growth. The analysis of variance showed no significant difference (p > 0.05) in the coefficients of determination between females (R = 0.96) and males (R = 0.84). Condition factors (K) were 3.07 and 1.23 for males and females respectively for M. cephalus in the reserve.


2015 ◽  
Vol 7 (1) ◽  
pp. 79-87
Author(s):  
María del Carmen Alejo-Plata ◽  
José Luis Gómez-Márquez ◽  
Jorge Eduardo Herrera-Galindo

There is practically no information on the biology of Lolliguncula (Loliolopsis) diomedeae. We analyzed specimens caught in four shrimp fishing trips in the Gulf of Tehuantepec in 1999-2001, 2004 and 2006.Sexual maturity and gonadosomatic index (GSI) were used as indicators of reproductive activity. A total of 1 200 individuals were captured, 89% female. Females ranged from 35 to 97mm in mantle length (LDM),with a mode at 80mm and weights 2 to 30,9g; males 20,7 to 65mm LDM with a mode at 35-40mm and weights from 0,4 to 12g. Differences in the LDM and the PT between males and females were significant (KS, p<0,05). The sex ratio was 8:1 H:M (p <0,05). The weight-length relationship type is potential for both sexes, with a negative allometric growth.83% of mature females had high IGS values, in contrast to less than 20% of mature males. The size at first maturity (L50) indicates that males (42,7mm LDM) mature when shorter than females (74,5mm LDM). Maturity, IGS and oceanographic features of the Gulf of Tehuantepec indicate that L. diomedeae spawn there.


2018 ◽  
Vol 10 (7) ◽  
pp. 11863
Author(s):  
Kamlesh Kumar Yadav ◽  
Rani Dhanze

Assessment of length-weight relationship (LWR), length-length relationship (LLR) and condition factor was carried out for Bangana dero in northeastern India, mainly from the Brahmaputra and Irrawaddy (Manipur) River system.  We report a value of ‘b’ 3.1269 and 3.1426 for LWR with respect to total length and standard length respectively, indicating positive allometric growth. The value of ‘b’ for LLR is less than one, which indicates that growth in total length is less with per unit increase in standard length.  The value of ‘K’ and ‘Kn’ is 0.91 and 0.72 depicts normal well being of fish in its habitat. 


Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 660
Author(s):  
Edoardo Bardi ◽  
Martina Manfredi ◽  
Raffaella Capitelli ◽  
Emanuele Lubian ◽  
Alessandro Vetere ◽  
...  

The use of long-acting gonadotropin-releasing hormone (GnRH) agonists to suppress fertility has been poorly investigated in reptiles, and the few available studies show inconsistent results. The efficacy of single and double intramuscular 4.7 mg deslorelin acetate implants in captive pond sliders (Trachemys scripta) was investigated, with 20 animals divided into three groups: a single-implant group (6 animals), a double-implant group (6 animals), and a control group (no implant). During one reproductive season (March to October), plasmatic concentration of sexual hormones (estradiol, progesterone, and testosterone) and ovarian morphometric activity via computed tomography were monitored about every 30 days. A significative decrease in the number of phase II ovarian follicles was detected in the double-implant group compared with the control group, but no significant difference was noted in the number of phase III and phase IV follicles, egg production, and plasmatic concentration of sexual hormones. Results show that neither a single nor a double deslorelin acetate implant can successfully inhibit reproduction in female pond sliders during the ongoing season, but the lower number of phase II follicles in the double-implant group can possibly be associated with reduced fertility in the following seasons.


Author(s):  
S.-H. Kim ◽  
H. Park ◽  
W. Kim ◽  
J.-H. Song ◽  
S.J. Roh ◽  
...  

The establishment of efficient and sustainable production of industrially important insects necessitates the detailed knowledge of the optimal mixture of macronutrients required for maximising their performance and fitness. The white spotted flower chafer, Protaetia brevitarsis (Coleoptera: Scarabaeidae: Cetoniinae), is one of the most important edible insects in East Asia with high nutritional and medicinal value. Here, we report how the ratio of protein to digestible carbohydrate (P:C) in the diet influenced lifespan and reproductive performance in the adults of P. brevitarsis. Throughout their lifespan, beetles were fed ad libitum one of five diets with differing P:C ratio (0:1, 3:7, 1:1, 7:3, 1:0). Both lifespan and the number of eggs produced over the lifetime were maximised at the P:C ratio of 3:7 and declined as the ratio deviated away from this optimal P:C composition. Beetles fed a diet containing only protein (P:C 1:0) not only had the shortest lifespan but also exhibited substantially reduced lifetime egg production compared to those fed the other diets. However, the effects of dietary P:C ratio on daily egg production rate and egg hatchability were marginal. The number of eggs produced at each age stage peaked at the age of week 2 and then gradually declined with increasing age, showing the sign of reproductive senescence. Age-specific egg production was higher in beetles confined to three intermediate P:C ratios (3:7, 1:1, 7:3) than those confined to two extreme P:C ratios (0:1, 1:0) throughout their lifespan. The speed of age-related decrease in reproductive performance was the slowest at P:C 3:7. Our data have implications for optimising the production of this edible insect with emerging economic importance.


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