Identification of the stages of ovarian maturation of the Argentine hake Merluccius hubbsi Marini, 1933 (Teleostei: Merlucciidae): advantages and disadvantages of the use of the macroscopic and microscopic scales

The Argentine hake Merluccius hubbsi is a demersal-pelagic species on which few studies have been undertaken, despite its importance for the fisheries of the South-Southeastern Brazilian region, . The species is the most important commercial fishery resource in Uruguay and Argentina, where several studies have permitted the proper monitoring of the species. The ovarian maturation of the Argentine hake is analysed in this study. A scale of maturation is presented in the light of the oocyte development and the use of macro and microscopic scales of ovarian maturation are compared. It was detected that the oocyte types and derived structures present in the ovaries are similar to those already described both for the species and for teleosts in general; group synchronous development and multiple spawning are typical. The identification of ovarian maturation based only on external morphological characteristics of the gonads presents many errors, mainly in the characterization of the stages of maturation, which makes imperative the parallel analysis of the oocyte development, undertaken through histological ovarian cross-sections.

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Merluccius hubbsi (Teleostei: Merlucciidae): stock identification based on reproductive biology in the south-southeast brazilian region

Brazilian Journal of Oceanography ◽

10.1590/s1679-87592009000100003 ◽

2009 ◽

Vol 57 (1) ◽

pp. 17-31 ◽

Cited By ~ 12

Author(s):

André Martins Vaz-dos-Santos ◽

Carmen Lúcia Del Bianco Rossi-Wongtschowski ◽

José Lima de Figueiredo

Keyword(s):

Temporal Variations ◽

Tierra Del Fuego ◽

Brazilian Coast ◽

Stock Identification ◽

Ovarian Maturation ◽

Environmental Features ◽

Important Target ◽

Merluccius Hubbsi ◽

Bottom Trawler ◽

Argentine Hake

The Argentine hake, Merluccius hubbsi, a demersal-pelagic species found from Rio de Janeiro, Brazil to the Tierra del Fuego, Argentina, has become an important target of the Brazilian bottom-trawler fleet since 2001. Earlier studies focusing on the species have suggested that more than one stock might occur off the Brazilian coast, in accordance with environmental features. In order to evaluate this hypothesis, fish were collected from four different areas in the Brazilian waters in which the hake is distributed, during the summers and winters of 1996-2001 and 2004, the females being used to analyze and compare spatial-temporal variations in ovarian maturation. Gonad indexes were also applied for the same purpose. Results indicate a north-south spawning gradient occurring as from summer at around 21°S to winter near 34°S, leading to the identification of two distinct stocks: one located between 21°S and 29°S (Southeastern stock) and the other between 29°S and 34°S (Southern stock), this latter shared with Uruguay and Argentina. Brazilian stocks present clear signs of overexploitation, the situation calling for an urgent solution.

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Diagnostic characteristics of Dirofilaria subdermata in cross sections

Canadian Journal of Zoology ◽

10.1139/z83-275 ◽

1983 ◽

Vol 61 (9) ◽

pp. 2097-2103 ◽

Cited By ~ 5

Author(s):

Yezid Gutierrez

Keyword(s):

United States ◽

Cross Sections ◽

Morphological Characteristics ◽

The United States ◽

Diagnostic Feature ◽

Erethizon Dorsatum ◽

Border States ◽

Diagnostic Characteristics ◽

Subcutaneous Tissues

A study of morphological characteristics in cross sections of Dirofilaria subdermata adults from the subcutaneous tissues of the Canadian porcupine (Erethizon dorsatum) is reported. A useful diagnostic feature which differentiates D. subdermata from a closely related filarid, D. ursi, occurring in bears, was found to be the number of longitudinal ridges. The relevance of these findings are discussed in relation to the human subcutaneous infections found in the United States and Canadian border states and provinces with D. ursi.

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Is the spawning frequency of Argentine hake, Merluccius hubbsi, affected by maternal attributes or physical variables?

Fisheries Research ◽

10.1016/j.fishres.2018.02.011 ◽

2018 ◽

Vol 204 ◽

pp. 147-155 ◽

Cited By ~ 3

Author(s):

Gustavo J. Macchi ◽

Karina Rodrigues ◽

Ezequiel Leonarduzzi ◽

Marina V. Diaz

Keyword(s):

Spawning Frequency ◽

Merluccius Hubbsi ◽

Physical Variables ◽

Argentine Hake

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Who let the YOY up? The pelagic habitat as a nursery and feeding ground area for the young‐of‐the‐year ( YOY ) Argentine hake, Merluccius hubbsi Marini, 1933

Journal of Fish Biology ◽

10.1111/jfb.14949 ◽

2021 ◽

Author(s):

Belleggia Mauro ◽

Gustavo L. Alvarez‐Colombo ◽

Santos Betina ◽

Castelletta Martin ◽

Mattera Belen

Keyword(s):

Feeding Ground ◽

Pelagic Habitat ◽

Merluccius Hubbsi ◽

Young Of The Year ◽

Argentine Hake

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Reproductive pattern of the Patagonian stock of Argentine hake (Merluccius hubbsi)

Fisheries Research ◽

10.1016/j.fishres.2004.09.006 ◽

2005 ◽

Vol 72 (1) ◽

pp. 97-108 ◽

Cited By ~ 40

Author(s):

Marcelo Pájaro ◽

Gustavo J. Macchi ◽

Patricia Martos

Keyword(s):

Reproductive Pattern ◽

Merluccius Hubbsi ◽

Argentine Hake

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Physiological and Anatomical Characterization of a Late-storage Root-forming Mutant of Sweetpotato

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.127.2.178 ◽

2002 ◽

Vol 127 (2) ◽

pp. 178-183 ◽

Cited By ~ 12

Author(s):

Makoto Nakatani ◽

Masaru Tanaka ◽

Masaru Yoshinaga

Keyword(s):

Cross Sections ◽

Ipomoea Batatas ◽

Root Formation ◽

Morphological Characteristics ◽

Zeatin Riboside ◽

Storage Root ◽

Storage Roots ◽

Physiological Mechanisms ◽

Maximum Root

A late-storage root-forming mutant (`KM95-A68') of sweetpotato [Ipomoea batatas (L.) Poir.] was characterized to clarify the genetic and physiological mechanisms of storage root formation. This mutant originated from a somaclonal mutation of `Kokei No. 14'. Storage roots of `KM95-A68' are rare and, when formed, develop 2 or 3 weeks later than those of `Kokei No. 14' from which it originated. Morphological characteristics of the canopy and leaf photosynthetic rates of `KM95-A68' were similar to those of `Kokei No. 14'. No apparent differences were observed in the anatomy of root cross sections of `KM95-A68' and `Kokei No. 14'. An apparent increase in the root zeatin riboside (ZR) levels were observed in `Kokei No. 14' at storage root formation. Root ZR levels differed between `Kokei No. 14' and `KM95-A68'. The onset of increase in root ZR levels was delayed by 2 or 3 weeks in `KM95-A68' in comparison to `Kokei No. 14'. Maximum root ZR levels in `Kokei No. 14' were 2.2 times higher in comparison to `KM95-A68'. This appeared to be a factor in delayed storage root formation of `KM95-A68'. Results of reciprocal grafts of `KM95-A68' and `Kokei No. 14' indicated that the late storage root-forming characteristic of `KM95-A68' is a characteristic that arises from the root itself.

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