Reprodução de Stellifer rastrifer (Jordan) (Teleostei, Sciaenidae) na Baía de Guaratuba, Paraná, Brasil Reproduction of Stellifer rastrifer (Jordan) (Teleostei, Sciaenidae) at the Guaratuba Bay, Paraná, Brazil

<abstract language="eng">A total of 1312 individuais of S. rastrifer were sampled from March 1994 to September 1996 at the Guaratuba Bay, Southern Brazilian coast. This species is a permanently inhabitant of the mangrove area throughout the year. The weight/length relationship of the species in the region is "In TW =-12,35 + 3,22 In TL", and the individuais may reach 172mm of total length. The analyses of gonadal morphology and gonadossomatic index indicate that S. rastrifer is a multiple spawner species, that reproduces at the mangrove area during a long period of the year. The reproductive activity is more intense during the winter and mainly the spring, when the value of Condition Factor declines and empty folheies are found in the ovaries

Atividade reprodutiva de Bairdiella ronchus (Cuvier) (Pisces, Sciaenidae) na Baía de Guaratuba, Paraná, Brasil Reproductive aspects of Bairdiella ronchus (Cuvier) at the Guaratuba Bay, Paraná, Brazil

<abstract language="eng">Bairdiella ronchus is one of the most common species of demersal ichthyofauna in Guaratuba Bay, south Brazil. However, this study reveals that is does not inhabits permanently the mangroove area. Individuals with more than 94mm total lenght leave mangroove area in late summer and early auntumn and returming in the spring. when they start ovarian veitellogenesis. During late spring and early summer, the oocytes are hydrated, and empty follicles can be found in the ovaries, indicating that this is the reproductive time for this species As other Sciaenidae. B. ronchus is a multiple spawner species

Haematological characteristics of freshwater-reared and wild mullet, Mugil platanus Günther (Osteichthyes, Mugilidae)

Mullets, Mugilplalanus Günther, 1880. were obtained from the estua-rine area of CananÉia (São Paulo, Brazil) and from freshwater tearing tanks. For each fish the body weight, body length, gonad weight and gonad maturation stage were recorded and the allometric index (K) was calculated. Blood was collected for hematocrit (Ht), hemoglobin level (lib), total cell count (Er), and the determination of hematological indices (MCV. MCH, MCHC), as well as the differential leukocyte count (lymphocytes, monocytes, neutrophils, basophils and '"other cells"). The averages of the hematological analyses, hematological indeces, condition factor and leukocytes percentage of the specimens acclimated to fresh water were significantly higher than those of the specimens from the estuary

Biologia reprodutiva do peixe-rei Odontesthes argentinensis (Valenciennes) (Atherinopsidae) da região marinha costeira do sul do Brasil Reproductive biology of silverside Odontesthes argentinensis (Valenciennes) (Atherinopsidae) of coastal sea region of the south of Brazil

O peixe-rei Odontesthes argentinensis (Valenciennes, 1835) distribui-se na região costeira do Atlântico Sul desde o sul do Brasil até a Argentina. Esta espécie apresenta duas populações, uma população residente no estuário da Lagoa dos Patos e outra na região marinha costeira. Este trabalho teve como objetivo determinar a biologia reprodutiva da população marinha costeira. A proporção sexual indicou predomínio de fêmeas. O tamanho de primeira maturação (L50) foi estimado em 13,8 cm CT para os machos e 16,1 cm CT para as fêmeas e o comprimento em que todos estão aptos para desovar (L100), foi estimado em 16,3 e 19,3 cm CT para machos e fêmeas, respectivamente. A relação gonadossomática indicou período reprodutivo entre final de agosto e início dezembro, período em que a temperatura da água se manteve abaixo dos 20ºC. Os fatores de condição total (KT) e somático (KS) apresentaram grandes variações ao longo do ciclo. Houve uma queda nos valores de K coincidindo com o início da desova estabelecendo uma relação com este período. Na análise do diâmetro dos ovócitos há evidências de três lotes caracterizando desova parcelada. A fecundidade total (FT) e por lote (FL) são proporcionais ao comprimento total. A média de ovócitos foi de 10.014 para FT e 3.651 para FL.<br>The silverside Odontesthes argentinensis (Valenciennes, 1835) is distributed in the coastal region of the South Atlantic since the south of Brazil until Argentina. This species presents two populations, a population resident in the Patos Lagoon estuary and another one in the coastal sea region. This work had as objective to determine the reproductive biology of the populations of coastal sea region. The sex ratio indicated predominance of females. The size of first maturation (L50) was estimated in 13.8 cm LT for the males and 16.1 cm LT for the females and the length where all were apt to spawn (L100) was estimated in 16.3 and 19.3cm LT for males and females, respectively. The gonadossomatic relation indicated reproductive period between ends of August and beginning of December, period where the temperature of the water is below 20ºC. The factors of total condition (KT) and somatic (KS) had presented great variations during the cycle. A fall in the values of K coincided with the beginning of the spawning, establishing a relation this fall of K represented the energy that was directed for the development of the gonads. In the analysis of the diameter of the oocytes evidence was found allowing state that the spawning don't occur at once. The total fecundity (TF) and the lot fecundity (LF) are proportional to the total length. The average of oocytes was of 10,014 for FT and 3,651 for FL