This page has only limited features, please log in for full access.

Dr. Rodolfo Garza-Torres
UNCIBNOR

Basic Info


Research Keywords & Expertise

0 Aquaponics
0 Nutrition
0 Aquaculture Systems
0 Tilapia
0 Sustainable Resources

Fingerprints

Aquaculture Systems
Tilapia

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Journal article
Published: 09 February 2020 in Aquaculture Reports
Reads 0
Downloads 0

The aim of this study was to evaluate Macrocystis pyrifera and Zea mays meals as nucleation sites in biofloc formation. Bioflocs were studied for a period of 12 weeks, by measuring volume, dry weight, organic matter, and ash weight. These were induced by the addition of bacterial inoculum, molasses and both types of meals to fresh water. After 4 weeks, a total of 100 tilapia fingerlings (1.60 ± 0.02 g weight and 4.76 ± 0.03 cm length) were transferred to 100 L tanks by triplicate for each treatment. Mean ± SD values of temperature (26.3 ± 0.2 °C), dissolved oxygen (3.42 ± .0.07 mg L−1), pH (7.95 ± 0.04), salinity (0.47 ± 0.01) and ammonia (0.245 ± 0.012 mg NH3 L−1) were similar in both treatments. However, floc volume of M. pyrifera was significantly higher (116.1 ± 20 ml L−1) than Z. mays flocs (58.4 ± 7.7 ml L−1), but had lower dry weight (55 ± 0.5 mg g−1 in M. pyrifera vs. 61 ± 2.0 mg g−1 in Z. mays). Fish weight and length gain and survival were significantly higher (p < 0.05) in M. pyrifera floc (13.7 ± 1.3 g; 4.5 cm; 90 %) than in Z. mays (12.3 g; 8.5 cm; 56 %). Aggregated organisms were classified into major groups and were quantified and identified to a genus level. Ciliates were detected on week 1 and rotifers and nematodes were first registered on weeks 3 and 4. These three groups were present in both treatments but were more abundant in maize biofloc. In conclusion, both types of nuclei resulted in the formation of bioflocs rich in aggregated organisms, but nuclei of M. pyrifera produced a significantly higher performance of tilapia fingerlings, probably because of the higher nutritional content of kelp over maize meal and higher flotation of M. pyrifera flocs, which remained longer in suspension making them readily available to the fish.

ACS Style

Benjamín Aparicio-Simón; Evelyn Real-Moreno; Daniel Espinosa-Chaurand; Ricardo García-Morales; Rodolfo Garza-Torres; Alejandro De Jesús Cortés-Sánchez; David Lora-Sanchez; Alfonso N. Maeda-Martínez. Giant bladder kelp (Macrocystis pyrifera) and maize (Zea mays) meals as nucleation sites for biofloc formation. Aquaculture Reports 2020, 16, 100289 .

AMA Style

Benjamín Aparicio-Simón, Evelyn Real-Moreno, Daniel Espinosa-Chaurand, Ricardo García-Morales, Rodolfo Garza-Torres, Alejandro De Jesús Cortés-Sánchez, David Lora-Sanchez, Alfonso N. Maeda-Martínez. Giant bladder kelp (Macrocystis pyrifera) and maize (Zea mays) meals as nucleation sites for biofloc formation. Aquaculture Reports. 2020; 16 ():100289.

Chicago/Turabian Style

Benjamín Aparicio-Simón; Evelyn Real-Moreno; Daniel Espinosa-Chaurand; Ricardo García-Morales; Rodolfo Garza-Torres; Alejandro De Jesús Cortés-Sánchez; David Lora-Sanchez; Alfonso N. Maeda-Martínez. 2020. "Giant bladder kelp (Macrocystis pyrifera) and maize (Zea mays) meals as nucleation sites for biofloc formation." Aquaculture Reports 16, no. : 100289.

Journal article
Published: 18 January 2020 in Sustainability
Reads 0
Downloads 0

Salicornia bigelovii Torr. is a potential new crop for coastal and saline lands, because of the oil content of its seeds, its properties as fresh vegetable, forage, and other uses. As a true halophyte, it can grow with seawater irrigation. The aim of this study was to determine the phenology and water requirements of Salicornia as a new plant resource in growing areas for salt-tolerant crops in coastal and saline lands, and elucidate scenarios of sustainability about these issues. Water requirements were estimated in experimental plots on the coastal line and fulfilled with drip irrigation connected to seawater aquaculture discharge ponds, 30 m from the sea. The recorded phenological events were germination, flowering, fructification, maturation, and physiological death. Results reflect the difficulty to adopt it as a new crop because of its long-life cycle, around nine months, contrasting with the life cycle of common crops, from three to four months. Irrigation needs reached a depth of 240 cm, significantly exceeding those of conventional crops. Such limitations are highlighted, but also its potential use as a biofilter of coastal aquaculture effluents, being a productive target-biomass, feasible to be used as a dual-purpose use of water and energy required in aquaculture farms.

ACS Style

Rodolfo Garza-Torres; Enrique Troyo-Diéguez; Alejandra Nieto-Garibay; Gregorio Lucero-Vega; Francisco Javier Magallón-Barajas; Emilio García-Galindo; Yenitze Fimbres-Acedo; Bernardo Murillo-Amador. Environmental and Management Considerations for Adopting the Halophyte Salicornia bigelovii Torr. as a Sustainable Seawater-Irrigated Crop. Sustainability 2020, 12, 707 .

AMA Style

Rodolfo Garza-Torres, Enrique Troyo-Diéguez, Alejandra Nieto-Garibay, Gregorio Lucero-Vega, Francisco Javier Magallón-Barajas, Emilio García-Galindo, Yenitze Fimbres-Acedo, Bernardo Murillo-Amador. Environmental and Management Considerations for Adopting the Halophyte Salicornia bigelovii Torr. as a Sustainable Seawater-Irrigated Crop. Sustainability. 2020; 12 (2):707.

Chicago/Turabian Style

Rodolfo Garza-Torres; Enrique Troyo-Diéguez; Alejandra Nieto-Garibay; Gregorio Lucero-Vega; Francisco Javier Magallón-Barajas; Emilio García-Galindo; Yenitze Fimbres-Acedo; Bernardo Murillo-Amador. 2020. "Environmental and Management Considerations for Adopting the Halophyte Salicornia bigelovii Torr. as a Sustainable Seawater-Irrigated Crop." Sustainability 12, no. 2: 707.

Journal article
Published: 22 November 2019 in Turkish Journal of Agriculture - Food Science and Technology
Reads 0
Downloads 0

Listeria monocytogenes is a food pathogen responsible for listeriosis, a relevant disease in public health worldwide. The genus Listeria spp., corresponds to cosmopolitan bacteria and capable of surviving different adverse conditions, which increases the risk for the food to be contaminated at any stage of the food chain. Fish and fish products are foods of high production level and, due to their chemical or nutritional composition, are highly susceptible to deterioration and contamination by pathogens in their productive chain relating to cases of listeriosis. Derived from the incidence and human mortality due to causative agents of listeriosis, along with their resistance to antimicrobials, they have acquired a greater emphasis on human health, animal health and food industry, resulting in the implementation of safety systems such as good hygiene practices, Hazard Analysis and Critical Control Points (HACCP) system, analytical methods and microbiological criteria, as some of the actions to contribute to the food safety and public health protection. The purpose of this review document is to provide, in a general way, aspects involved in foodborne illnesses, specifically listeriosis and its association with fish as a transmitting food, considering the prevention and control measures of this disease through food. It also includes aspects related to antimicrobial resistance by bacterial isolates obtained from fish, their implications and health risks.

ACS Style

Alejandro De Jesús Cortés Sánchez; Martha Lorena Guzmán Robles; Rodolfo Garza Torres; Luis Daniel Espinosa Chaurand; Mayra Diaz Ramirez. Food Safety, Fish and Listeriosis. Turkish Journal of Agriculture - Food Science and Technology 2019, 7, 1908 -1916.

AMA Style

Alejandro De Jesús Cortés Sánchez, Martha Lorena Guzmán Robles, Rodolfo Garza Torres, Luis Daniel Espinosa Chaurand, Mayra Diaz Ramirez. Food Safety, Fish and Listeriosis. Turkish Journal of Agriculture - Food Science and Technology. 2019; 7 (11):1908-1916.

Chicago/Turabian Style

Alejandro De Jesús Cortés Sánchez; Martha Lorena Guzmán Robles; Rodolfo Garza Torres; Luis Daniel Espinosa Chaurand; Mayra Diaz Ramirez. 2019. "Food Safety, Fish and Listeriosis." Turkish Journal of Agriculture - Food Science and Technology 7, no. 11: 1908-1916.

Original article
Published: 19 August 2019 in Aquaculture Research
Reads 0
Downloads 0

Recirculating aquaculture systems (RASs) are an efficient method for developing sustainable aquaculture and the development of a feed strategy for RASs could be a key factor for the success of culturing Oreochromis niloticus. The daily protein intake (DPI) mathematical function related to body weight (BW) was designed (DPI = −3.818 ln (BW) + 30.158) named DPI 1.0 = 100%. Three feeding rates were established, DPI 1.4, 1.2 and 1.0, and were implemented in an RAS production cycle (100 fish/m3) for 34 weeks. The final growth measurements were 908.0 ± 57.9 g (DPI 1.4), 887.0 ± 113.5 g (DPI 1.2) and 702.2 ± 38.1 g (DPI 1.0) (p < .05), with feed conversion rates (FCRs) of 2.3, 1.9 and 1.9, respectively; the survival was ≥ 98.3% (p > .05) for all treatments. DPI levels conditioned the growth of the fish and the proportion of lipid: protein in the bodies of O. niloticus but not in the fillets. The mathematical function DPI 1.2 = 120% (DPI = −4.582 ln (BW) + 36.19) used in the RAS at the 40% protein level improved fish growth, the protein efficiency ratio and FCRs. The DPI values were estimated for 49 different cases and feeding strategies showed lower values than most of the different DPI mathematical functions used and cited in this work. Therefore, DPI metric is a good tool that provides the specific requirements of protein for O. niloticus growth, which can enable farmers to ration feed and improve energy use (kWh/fish) and facilitate the integration of RAS with horticulture.

ACS Style

Yenitze E. Fimbres‐Acedo; Rodolfo Garza‐Torres; Masato Endo; Rosalía Servín‐Villegas; Kevin M. Fitzsimmons; Maurício G. C. Emerenciano; Francisco J. Magallón‐Barajas. Performance of Oreochromis niloticus in recirculating aquaculture systems at different levels of daily protein intake. Aquaculture Research 2019, 50, 3326 -3342.

AMA Style

Yenitze E. Fimbres‐Acedo, Rodolfo Garza‐Torres, Masato Endo, Rosalía Servín‐Villegas, Kevin M. Fitzsimmons, Maurício G. C. Emerenciano, Francisco J. Magallón‐Barajas. Performance of Oreochromis niloticus in recirculating aquaculture systems at different levels of daily protein intake. Aquaculture Research. 2019; 50 (11):3326-3342.

Chicago/Turabian Style

Yenitze E. Fimbres‐Acedo; Rodolfo Garza‐Torres; Masato Endo; Rosalía Servín‐Villegas; Kevin M. Fitzsimmons; Maurício G. C. Emerenciano; Francisco J. Magallón‐Barajas. 2019. "Performance of Oreochromis niloticus in recirculating aquaculture systems at different levels of daily protein intake." Aquaculture Research 50, no. 11: 3326-3342.

Journal article
Published: 10 July 2019 in Latin American Journal of Aquatic Research
Reads 0
Downloads 0
ACS Style

David Palma Cancino; Benjamin Aparicio Simon; Alejandro De Jesús Cortés-Sánchez; Rodolfo Garza-Torres; Ricardo Garcia Morales; Alfonso N. Maeda-Martínez. Bioeconomic profitability analysis of tropical gar (Atractosteus tropicus) grow out using two commercial feeds. Latin American Journal of Aquatic Research 2019, 47, 440 -448.

AMA Style

David Palma Cancino, Benjamin Aparicio Simon, Alejandro De Jesús Cortés-Sánchez, Rodolfo Garza-Torres, Ricardo Garcia Morales, Alfonso N. Maeda-Martínez. Bioeconomic profitability analysis of tropical gar (Atractosteus tropicus) grow out using two commercial feeds. Latin American Journal of Aquatic Research. 2019; 47 (3):440-448.

Chicago/Turabian Style

David Palma Cancino; Benjamin Aparicio Simon; Alejandro De Jesús Cortés-Sánchez; Rodolfo Garza-Torres; Ricardo Garcia Morales; Alfonso N. Maeda-Martínez. 2019. "Bioeconomic profitability analysis of tropical gar (Atractosteus tropicus) grow out using two commercial feeds." Latin American Journal of Aquatic Research 47, no. 3: 440-448.

Journal article
Published: 01 March 2015 in Aquaculture
Reads 0
Downloads 0
ACS Style

Grecia Vázquez-Islas; Danitzia A. Guerrero-Tortolero; Rodolfo Garza-Torres; Píndaro Álvarez-Ruiz; Humberto Mejía-Ruiz; Rafael Campos-Ramos. Quantitative analysis of hypertrophy and hyperactivity in the androgenic gland of eyestalk-ablated male Pacific white shrimp Litopenaeus vannamei during molt stages. Aquaculture 2015, 439, 7 -13.

AMA Style

Grecia Vázquez-Islas, Danitzia A. Guerrero-Tortolero, Rodolfo Garza-Torres, Píndaro Álvarez-Ruiz, Humberto Mejía-Ruiz, Rafael Campos-Ramos. Quantitative analysis of hypertrophy and hyperactivity in the androgenic gland of eyestalk-ablated male Pacific white shrimp Litopenaeus vannamei during molt stages. Aquaculture. 2015; 439 ():7-13.

Chicago/Turabian Style

Grecia Vázquez-Islas; Danitzia A. Guerrero-Tortolero; Rodolfo Garza-Torres; Píndaro Álvarez-Ruiz; Humberto Mejía-Ruiz; Rafael Campos-Ramos. 2015. "Quantitative analysis of hypertrophy and hyperactivity in the androgenic gland of eyestalk-ablated male Pacific white shrimp Litopenaeus vannamei during molt stages." Aquaculture 439, no. : 7-13.

Journal article
Published: 01 May 2014 in Journal of Crustacean Biology
Reads 0
Downloads 0

The location of the androgenic gland in the genital organ in male Pacific white shrimp Litopenaeus vannamei (Boone, 1931) was analyzed by histology and expression of the insulin-like androgenic gland hormone precursor gene (Lv-IAG). The androgenic gland in L. vannamei is a group of three conspicuous semicircular cellular masses interconnected by cord-like androgenic gland cells, in parallel and attached to the distal vas deferens and terminal ampoule, which form a hook-like morphology. Lv-IAG expression occurs mainly at the terminal ampoule, but also at the distal part of the descending medium vas deferens and the narrow distal vas deferens. These specific regions of Lv-IAG expression basically match the anatomical localization of the androgenic gland observed by histology. The complete cDNA nucleotide sequence of Lv-IAG precursor had 87% to Fenneropenaeus chinensis (Osbeck, 1765), 84% identity to Penaeus monodonFabricius, 1798 (Pm-IAG), and 82% to Marsupenaeus japonicus (Bate, 1888) (Maj-IAG). The deduced encoding sequence from an open reading frame of |$507 \, {\rm bp}$| contained a signal peptide, a B chain, a C peptide, and an A chain that correspond to the androgenic gland insulin-like hormone polypeptide in decapods, where six highly conserved cysteine residues of the A and B chains fold the mature peptide through disulfide bridges. The amino-acid sequence showed high identity to P. monodon (80%), F. chinensis (80%), and M. japonicus (72%), whereas the match to other decapod families Palaemonidae, Parastacidae, and Portunidae was low (24-32%). This study extends our knowledge of the molecular structure of insulin-like peptides related to sex differentiation in malacostraca.

ACS Style

Grecia Vázquez-Islas; Rafael Campos-Ramos; Rodolfo Garza-Torres; Danitzia A. Guerrero-Tortolero. Histology of the androgenic gland and expression of the insulin-like androgenic gland hormone precursor gene in the genital organ of Pacific white shrimp Litopenaeus vannamei. Journal of Crustacean Biology 2014, 34, 293 -299.

AMA Style

Grecia Vázquez-Islas, Rafael Campos-Ramos, Rodolfo Garza-Torres, Danitzia A. Guerrero-Tortolero. Histology of the androgenic gland and expression of the insulin-like androgenic gland hormone precursor gene in the genital organ of Pacific white shrimp Litopenaeus vannamei. Journal of Crustacean Biology. 2014; 34 (3):293-299.

Chicago/Turabian Style

Grecia Vázquez-Islas; Rafael Campos-Ramos; Rodolfo Garza-Torres; Danitzia A. Guerrero-Tortolero. 2014. "Histology of the androgenic gland and expression of the insulin-like androgenic gland hormone precursor gene in the genital organ of Pacific white shrimp Litopenaeus vannamei." Journal of Crustacean Biology 34, no. 3: 293-299.

Journal article
Published: 01 May 2014 in Journal of Crustacean Biology
Reads 0
Downloads 0

Abnormalities and possible mosaicism during embryonic cell division after cold shock of zygotes of Litopenaeus vannamei (Boone, 1931) were related to the failure of induction of polyploidy. Eggs were treated to 10 minutes cold shock at |$8^\circ {\rm C}$| to arrest the second polar body (triploid-induced eggs) or first cleavage (tetraploid-induced eggs). In both cases, asynchrony and abnormalities among embryos were observed. In some triploid-induced eggs, three haploid pronuclei, instead of two, were seen at the center of the egg, and none in the periphery. These three nuclei may serve to evaluate methods of triploid induction in penaeids. In tetraploid-induced eggs, a tetrapolar or a bipolar spindle was inferred. The common abnormality in the anaphase with a tetrapolar spindle came with an off-center position of the nucleus, ending in a 2-cell stage with either a blastomere with one complete nucleus |$(4n)$| or two separate nuclei (⁠|$2n$| and |$2n$|⁠), both with one anucleated |$(0n)$| blastomere. Other abnormalities produced 3- and 4-cell stages with one to three anucleated |$(0n)$| blastomeres, including one putative mosaic. In triploid-induced eggs, the main abnormalities came with syngami between two pronuclei only, ending in a putative 4-cell stage 1:1 triploid |$(3n)$|⁠: diploid |$(2n)$| mosaic egg or without syngamy, ending in a putative 4-cell stage 2:1:0 diploid |$2(2n)$|⁠: haploid |$(n)$|⁠: anucleated |$(0n)$| mosaic egg, and perhaps a putative 1:1 diploid |$(2n)$|⁠: haploid |$(n)$| mosaic egg. Less frequent 4-cell stage arrangements had 1:1 sextaploid |$(6n)$|⁠: anucleated |$(0n)$| and 1:3 one nucleated |$(3n)$| and three anucleated |$(0n)$| blastomeres. We suggest that inherent problems in L. vannamei embryos are related to lethal occurrences of putative nauplii mosaics. Alternative methods to induce polyploidy are needed for this species.

ACS Style

Manuel De Jesús Zúñiga-Panduro; Rodolfo Garza-Torres; Ramón Casillas-Hernández; Rafael Campos-Ramos; José Manuel Grijalva-Chon; Danitzia A. Guerrero-Tortolero. Abnormalities and possible mosaicism during embryonic cell division after cold shock in zygotes of the Pacific white shrimp, Litopenaeus vannamei, related to failure of induction of tetraploidy and triploidy. Journal of Crustacean Biology 2014, 34, 367 -376.

AMA Style

Manuel De Jesús Zúñiga-Panduro, Rodolfo Garza-Torres, Ramón Casillas-Hernández, Rafael Campos-Ramos, José Manuel Grijalva-Chon, Danitzia A. Guerrero-Tortolero. Abnormalities and possible mosaicism during embryonic cell division after cold shock in zygotes of the Pacific white shrimp, Litopenaeus vannamei, related to failure of induction of tetraploidy and triploidy. Journal of Crustacean Biology. 2014; 34 (3):367-376.

Chicago/Turabian Style

Manuel De Jesús Zúñiga-Panduro; Rodolfo Garza-Torres; Ramón Casillas-Hernández; Rafael Campos-Ramos; José Manuel Grijalva-Chon; Danitzia A. Guerrero-Tortolero. 2014. "Abnormalities and possible mosaicism during embryonic cell division after cold shock in zygotes of the Pacific white shrimp, Litopenaeus vannamei, related to failure of induction of tetraploidy and triploidy." Journal of Crustacean Biology 34, no. 3: 367-376.

Journal article
Published: 01 February 2011 in Journal of Crustacean Biology
Reads 0
Downloads 0
ACS Style

Rodolfo Garza-Torres; Hortencia Obregon-Barboza; Danitzia A. Guerrero-Tortolero; Rafael Campos-Ramos; Alejandro M. Maeda-Martínez. Description of Meiosis in Female and Male Pacific White Shrimp Litopenaeus vannamei (Decapoda: Penaeidae). Journal of Crustacean Biology 2011, 31, 75 -81.

AMA Style

Rodolfo Garza-Torres, Hortencia Obregon-Barboza, Danitzia A. Guerrero-Tortolero, Rafael Campos-Ramos, Alejandro M. Maeda-Martínez. Description of Meiosis in Female and Male Pacific White Shrimp Litopenaeus vannamei (Decapoda: Penaeidae). Journal of Crustacean Biology. 2011; 31 (1):75-81.

Chicago/Turabian Style

Rodolfo Garza-Torres; Hortencia Obregon-Barboza; Danitzia A. Guerrero-Tortolero; Rafael Campos-Ramos; Alejandro M. Maeda-Martínez. 2011. "Description of Meiosis in Female and Male Pacific White Shrimp Litopenaeus vannamei (Decapoda: Penaeidae)." Journal of Crustacean Biology 31, no. 1: 75-81.

Journal article
Published: 01 November 2009 in Aquaculture
Reads 0
Downloads 0

Timing of organogenesis and subsequent development of genital organs were studied in female and male Pacific white shrimp Penaeus (Litopenaeus) vannamei postlarvae. This was linked to the timing of differentiation of external structures that differentiate the genders. Anatomy of the gonad appears to be unique for penaeid species. The genital organ was fully recognized from postlarve day-16 (PL16) as a bilateral lobe located in the anterior region of the midgut gland (first anterior lobes) that connects to an anterior perpendicular collector tube that extends dorsally towards the posterior region of the midgut gland and forms an inverted U-shape collector. Eight bilateral lobes in females (second to ninth) and the bilateral oviduct between the seventh and eighth lateral lobes and seven bilateral lobes in the male (second to eighth) are connected along the inverted U-shape collector tube. These lobes extend over the surface of the midgut gland beneath the pericardium. Shortly after organogenesis of the female gonad, the tenth bilateral lobe emerges from the distal region of the collector tube and continues dorsally along the intestine, and the fourth bilateral lobe did not develop and regressed until apparently absorbed. In males, the posterior bilateral vas deferens emerges from the same region. Around PL50 (0.5–0.6 g; 45–50 mm), external gender differentiation was recognized in the form of the thelycum in females and the gonopores in males. Additionally, the male androgenic gland appears at the posterior-external wall of each anterior vas deferens, surrounded by connective tissue that attaches to the anterior vas deferens and the eighth testicular lobe. Gonad differentiation occurred from PL68 (1.8–2.2 g; 70–74 mm), where it was possible to differentiate the female ovary from the male testes. Timing of sex reversal studies in penaeids is discussed.

ACS Style

Rodolfo Garza-Torres; Rafael Campos-Ramos; Alejandro M. Maeda-Martínez. Organogenesis and subsequent development of the genital organs in female and male Pacific white shrimp Penaeus (Litopenaeus) vannamei. Aquaculture 2009, 296, 136 -142.

AMA Style

Rodolfo Garza-Torres, Rafael Campos-Ramos, Alejandro M. Maeda-Martínez. Organogenesis and subsequent development of the genital organs in female and male Pacific white shrimp Penaeus (Litopenaeus) vannamei. Aquaculture. 2009; 296 (1):136-142.

Chicago/Turabian Style

Rodolfo Garza-Torres; Rafael Campos-Ramos; Alejandro M. Maeda-Martínez. 2009. "Organogenesis and subsequent development of the genital organs in female and male Pacific white shrimp Penaeus (Litopenaeus) vannamei." Aquaculture 296, no. 1: 136-142.

Journal article
Published: 17 October 2006 in Aquaculture Research
Reads 0
Downloads 0

Environmental effects on sex determination in Litopenaeus vannamei were studied by rearing day 1 postlarvae at three temperatures, under three photoperiods, at high density and by starving. None of the environmental conditions affected sex determination or differential development of gender in this species. From day 50, the development of the endopodite of the first pair of pleopods revealed the first external differentiation, showing a triangular structure with three setae in females, whereas a tubular structure remained in males. Juvenile shrimp sex differentiation took place from days 50–90, independent of size, only if postlarvae reached a development threshold of 150 mg of body weight and 20 mm of body length previously. Histology and scanning electron microscopy of the vas deferens revealed that the androgenic gland (AG) is a single 2‐mm cord attached in the subterminal ejaculatory region, just before the distal vas deferens narrows. The AG is composed of large oval cells containing vacuolated cytoplasm, and each cell has a prominent rounded nucleus, similar to all descriptions of the AG in Malacostracans, so we assume that it should have the same function in sex differentiation.

ACS Style

Rafael Campos-Ramos; Rodolfo Garza-Torres; Danitzia A Guerrero-Tortolero; Alejandro M Maeda-Martínez; Hortencia Obregon-Barboza. Environmental sex determination, external sex differentiation and structure of the androgenic gland in the Pacific white shrimp Litopenaeus vannamei (Boone). Aquaculture Research 2006, 37, 1583 -1593.

AMA Style

Rafael Campos-Ramos, Rodolfo Garza-Torres, Danitzia A Guerrero-Tortolero, Alejandro M Maeda-Martínez, Hortencia Obregon-Barboza. Environmental sex determination, external sex differentiation and structure of the androgenic gland in the Pacific white shrimp Litopenaeus vannamei (Boone). Aquaculture Research. 2006; 37 (15):1583-1593.

Chicago/Turabian Style

Rafael Campos-Ramos; Rodolfo Garza-Torres; Danitzia A Guerrero-Tortolero; Alejandro M Maeda-Martínez; Hortencia Obregon-Barboza. 2006. "Environmental sex determination, external sex differentiation and structure of the androgenic gland in the Pacific white shrimp Litopenaeus vannamei (Boone)." Aquaculture Research 37, no. 15: 1583-1593.