Feeding protocol with live feed and inert diet to determine the ideal age/size for weaning mullet Mugil liza (Valenciennes, 1836).

The Lebranche mullet Mugil liza is a marine fish of great importance for artisanal and industrial fishing, as well as aquaculture. The use of live feeds during the larviculture phase of marine fish is a significant component of production costs. The present study evaluated the effects of the feeding transition on different larval stages of M. liza, from the combined supply of live feed (Brachionus rotundiformis + Artemia franciscana) and live + inert feed (Artemia franciscana + inert diet) until the weaning phase to only the inert diet. A total of 3240 M. liza larvae (weight 0.0133 ± 0.0062 g and length 0.793 ± 0.160 cm) were distributed among the 12 experimental units (n = 270), resulting in four groups with three replicates each. Treatment groups consisted of feed transition with A. franciscana (enriched metanauplii) to commercial inert feed starting weaning at four different larval ages: 28, 31, 34, and 37 days post hatching. Zootechnical performance indexes and intestinal histomorphometry were evaluated. Mortality, condition factor, and length variation coefficient did not show significant differences between treatments. Final weight, final length, weight gain, and length gain were significantly greater in larvae that started weaning at 31, 34, and 37 days post hatching. Weight coefficient of variation was significantly higher in larvae that started weaning at 28 days (67.51 ± 11.70) compared to 37 days (34.40 ± 7.30). In intestinal histology, villi height (180.3 ± 4.4) was significantly higher in larvae that started weaning at 37 days post hatching. Considering the evidence found in the present study, it is recommended to start weaning M. liza on the 31st day post-hatching, using a 2-day co-feeding protocol (31st and 32nd days). From the 33rd day after hatching, M. liza larvae can receive only commercial feed.

Dietary effect of multi-strain prebiotics and probiotics on growth, hemato-biochemical parameters, intestinal histomorphometry, and resistance to hypoxia in juvenile tambaqui (Colossoma macropomum).

This study evaluated the effects of a multi-strain prebiotics and probiotics on the diet of tambaqui Colossoma macropomum. One hundred and fifty juvenile tambaqui (20.2 ± 3.6 g and 10.32 ± 5.78 cm) were randomly distributed in 15 experimental units with a volume of 80 L and fed for 45 days with a diet containing the symbiotic additive at five inclusion levels (0, 2, 4, 6 and 8 g kg feed- 1). At the end of the period, growth performance, survival, hemato-biochemical and intestinal parameters, as well as the fish's resistance to stress were evaluated. The additive did not alter the growth performance, hemato-biochemical and intestinal parameters of the tambaqui. However, the hemato-biochemical parameters of aspartate aminotransferase (AST), plasma protein, hematocrit, glucose, triglycerides and cholesterol showed differences between treatments after the stress challenge. AST increased significantly during challenge and post-challenge. Plasma protein increased significantly during and after the challenge. The hematocrit was highest at 48 h after the challenge and lowest in the 2 g, 6 g and 8 g groups. Glucose was significantly reduced 24 h after the challenge, while triglycerides were lower 24 h and 48 h after the challenge. Cholesterol increased significantly in the challenge. There was an interaction between the factors sampling time and symbiotic concentration for hematocrit and glucose. In hypoxic stress situations, the 2 g concentration was more favorable for the fish. We recommend further studies with 2 g kg feed- 1 in trials lasting more than 45 days.

Growth, survival, and myogenic gene expression in the post-larvae of Colossoma macropomum provisioned with Artemia nauplii.

Artemia nauplii are widely used as fish larvae feed due to its beneficial nutritional characteristics for larval development; however, efficient feeding strategies are needed to balance its high costs. Therefore, we evaluated the effects of different densities of Artemia nauplii (100, 250, 500, 750, and 1000 nauplii/post-larvae) on the growth, survival, water quality, and myogenic gene expression of tambaqui (Colossoma macropomum) post-larvae cultivated in a recirculating aquaculture system. After 2 weeks of trial, there was a significant decrease in dissolved oxygen concentration with the increase in nauplii density, but it did not interfere with larval performance and survival. In the first week, larvae fed with fewer than 500 nauplii/post-larvae presented slower growth, while in the second week, larvae fed with 1000 nauplii/post-larvae had the highest final weight and length. Regression analysis suggests that the optimum feeding density of Artemia nauplii during the first week is 411 nauplii/post-larvae, while for the second week, the growth increased proportionally to the feeding densities. The relative expression of the myod, myog, and mstn genes was higher in larvae fed with fewer than 500 nauplii/post-larvae. Although low-growing larvae showed increased expression of myod and myog genes, responsible for muscle hyperplasia and hypertrophy, respectively, mstn expression may have played a significant inhibitory role in larval development. Further research is needed to better determine the effects of the live food on the zootechnical performance and the expression of the myogenic genes in the initial phase of the life cycle of the tambaqui post-larvae.

Effect of total hardness of water on juvenile mullets (Mugil liza) raised in fresh water / Efeito da dureza total em juvenis de tainha (Mugil liza) criados em água doce

The aim of this study was to evaluate the effects of three fresh-water samples with different hardness values (25, 250, and 750 mg L-1 CaCO3) and a control (sea water with salinity 15% and hardness 2500 ± 130.9 mg L-1 CaCO3) on Mugil liza (mullet) juveniles by conducting a long-term test (for 50 days). Zootechnical performance [weight gain (WG), feed conversion rate, specific growth rate, and survival (%)], stress indicator parameters (glucose), and physiological parameters in gill tissues were analyzed to determine the fresh-water hardness range that can allow the optimal survival, growth, and feed conversion for the species. Fish with a mean initial weight of 22 ± 2.84 g were maintained under constant conditions of temperature, pH, alkalinity, and ammonia concentration, and they were fed four times per day with a commercial diet. When evaluating zootechnical performance, only survival (%) was not significantly different among treatments. For the other variables­weight gain, feed conversion, and specific growth rate­the best results were found in the treatment with 15% salinity (control). Blood glucose levels in animals maintained at 15% salinity (control) were significantly lower than those observed in the other treatments. Histological analyses corroborated the zootechnical data, potentially indicating stress in fish maintained at very low and very high water hardness. In conclusion, for cultivating juvenile mullets in fresh water, the most suitable hardness value was 250 mg L-1 CaCO3, because the best final weight of fish was achieved in that condition.(AU)

O objetivo desse estudo foi avaliar o efeito de três durezas diferentes de água doce (25, 250 e 750 mg.L-1 CaCO3) e controle (água do mar com salinidade 15 % e dureza 2500 ± 130,9 mg.L-1 CaCO3), em juvenis de tainha Mugil Liza , através de um teste de longo prazo (50 dias), avaliando o desempenho zootécnico (ganho de peso (GP), conversão alimentar (CA), taxa de crescimento específico (TCE) e sobrevivência (%)), parâmetros indicadores de estresse (glicose) e avaliação de parâme-tros fisiológicos nos tecidos das brânquias, a fim de determinar a faixa de dureza em água doce onde há melhor sobrevivência, crescimento e conversão alimentar dessa espécie. Os peixes com peso médio inicial de 22 ± 2,84g foram mantidos em condi-ções constantes de temperatura, pH, alcalinidade e amônia, e alimentados quatro vezes ao dia com dieta comercial. Ao avaliar o desempenho zootécnico apenas a sobrevivência (%) não foi significativamente diferente entre os tratamentos, porém, para as demais variáveis: ganho de peso (GP), conversão alimentar (CA) e taxa de crescimento específico (TCE) os melhores resul-tados foram encontrados no tratamento com salinidade 15 % (controle). A glicose no sangue dos animais mantidos a salini-dade 15 % (controle) foi significativamente menor em relação aos outros tratamentos. As análises histológicas corroboram os dados zootécnicos, indicando possivelmente stress nos peixes mantidos em durezas muito baixas e muito altas. Conclui-se que para cultivar juvenis de tainha em água doce, a dureza mais adequada é 250 mg.L-1 CaCO3, pois apresentou melhor peso final dentre as durezas avaliadas.(AU)

Influence of salinity on growth and survival of juvenile Sardinella brasiliensis / Influência da salinidade no crescimento e sobrevivência de juvenis de Sardinella brasiliensis

The aim of the study was to evaluate the influence of changes in seawater salinity on juvenile Brazilian sardine (Sardinella brasiliensis). Through two assays, the LC50 (96 h) and the zootechnical performance (42 days) were determined, respectively. In the first assay, six treatments of salinity 0, 7, 14, 21, 28 and 35 parts per thousand (ppt) with three replicates were established. For this, 100-L cylinder-conical tanks were used, with 30 individuals with 45-day after eclosion (DAE) per unit, without water renewal and feeding. In the groups of salinity 0 and 7 ppt, all fish died on the first day. The LC50 was estimated at salinity 11.13 ppt. The second trial was designed with five treatments (salinity 7, 14, 21, 28 and 35 ppt), with three replicates. Two thousand-L cylindrical-conical tanks were used, with 30 individuals (58 DAE) per unit, with water renewal and feeding until apparent satiation. In the treatment salinity 7 ppt, all fish died by the second day. At salinity 35 ppt, the highest growth rates (2.78 g) and survival (100%) were observed. Salinity 14 ppt had the lowest survival (83%) and growth (1.48 g). We concluded that the juvenile sardines can be adapted to environments with salinity from 14 ppt, with significant losses. However, salinity 35 ppt showed the highest survival and growth rates.(AU)

O objetivo do estudo foi avaliar a influência da variação da salinidade na água do mar em juvenis de sardinha brasileira (Sardinella brasiliensis). Por meio de dois ensaios, determinaram-se a CL50 (96 h) e o desempenho zootécnico (42 dias), respectivamente. No primeiro ensaio foram estabelecidos seis tratamentos de salinidade 0, 7, 14, 21, 28 e 35 parts per thousand (ppt) com três repetições. Para isso, foram utilizados tanques cilindro-cônicos de 100 L com 30 peixes (45 dias após eclosão ­ DAE) por unidade, sem renovação de água e sem alimentação. Nos grupos de salinidade 0 e 7 ppt todos os peixes morreram no primeiro dia. O LC50 foi estimado na salinidade 11,13 ppt. O segundo ensaio foi delineado com cinco tratamentos (salinidade 7, 14, 21, 28 e 35 ppt), com três repetições. Foram empregados tanques cilíndrico-cônicos de 200 L, com 30 indivíduos (58 DAE) por unidade, com renovação de água e alimentação até a saciedade aparente. No tratamento salinidade 7 ppt, todos os peixes morreram no segundo dia. Na salinidade 35 ppt foram observadas as maiores taxas de crescimento (2,78 g) e sobrevivência (100%). A salinidade 14 ppt teve a menor sobrevivência (83%) e crescimento (1,48 g). Concluímos que os juvenis de sardinha podem se adaptar a ambientes com salinidade de 14 ppt em diante, com perdas significativas, no entanto a salinidade 35 ppt apresentou as maiores taxas de sobrevivência e crescimento.(AU)

Amyloodiniosis in farmed Sardinella brasiliensis (Steindachner, 1879): Case report of successful therapeutic control with copper sulfate.

Brazilian sardine is emerging as a promising species in Aquaculture. This study describes for the first time a case of parasitic infestation by Amyloodinium in Brazilian sardines Sardinella brasiliensis obtained from natural spawning in captivity. The sardines kept in nurseries were naturally parasitized by the amylodiniosis causative agente the dynoflagellate A. ocellatum with high mortalities above 50%. Fish presented clinical signs characteristic of amyloodiniosis which included easily perceived behavioral changes such as loss of appetite, scraping of the body against objects, walls and bottom, nursery pipes, agglomerations near the aerators and water inlets, presented with accelerated opercular beating and erratic swimming. For therapeutic treatment copper sulfate was used for 10 days. At the end of the treatment period the fish had no clinical signs or presence of the parasite on the body surface, indicating that the application of copper sulfate in concentration of 0.2 mg L-1 of Cu+ was effective to control this parasite, apparently without causing damage to Brazilian sardine.

Spontaneous spawning of Brazilian sardine in captivity / Desovas espontâneas da sardinha-verdadeira em cativeiro

In one year, 76 first generation (F1) Brazilian sardine Sardinella brasiliensis breeders spawned 84 times spontaneously in captivity. This is the first report for the genus Sardinella. Following the pattern found in the natural environment, the number of spawns, as well as fertilization and hatching rates were higher in spring, summer and fall than in winter. Until now, winter spawning was only presumed to occur in a natural environment. Water temperature, and not photoperiod, was positively correlated with reproductive performance.

Durante um ano, 76 reprodutores de primeira geração (F1) de sardinha-verdadeira Sardinella brasiliensis desovaram espontaneamente 84 vezes em cativeiro. Esse é o primeiro relato dentro do gênero Sardinella. Seguindo o padrão do ambiente natural, o número de desovas e as taxas de fertilização e eclosão foram maiores na primavera, verão e outono que no inverno. Até o momento, a desova no inverno foi presumida apenas no ambiente natural. A temperatura da água, e não o fotoperíodo, apresentou correlação positiva com o desempenho reprodutivo.

Feeding frequency in rearing juveniles of suruvi Steindachneridion scriptum / Frequência alimentar na criação de juvenis de suruvi Steindachneridion scriptum

The present study aimed to determine the ideal feeding frequency of feeding for suruvi juvenile. A study was conducted over 60 days to determine the effects of feeding frequency on growth metrics, body composition, and digestive enzyme activity of juvenile suruvi (initial mean weight: 60.19 ± 10.67 g). The experimental units were 1.0 m3 circular tanks, stocked with 94 fish, connected to a recirculating aquaculture system. The feed was offered during the dark phase of the 12:12 photoperiod with the following treatments in triplicate: FF1 = once a day at 20:00h; FF2 = twice a day at 20:00h and 06:00h; and FF3 = three times a day at 20:00h, 01:00h, and 06:00h. The fish fed a commercial carnivorous fish feed comprised of 42% crude protein, 11% lipids, 20% carbohydrates, and 4,380 kcal kg-1 of crude energy in 6.0 mm pellets. At the end of the feeding, no significant differences were observed in the growth variables, body composition of proteins and lipids, and alkaline proteases and lipase activity (p>0.05) between treatments. However, there were significant differences in amylase activity (p<0.05). Our findings demonstrated that suruvi juveniles could be sustainably fed only once a day.

O presente estudo teve como objetivo determinar a frequência de alimentação para juvenis de suruvi. Foi realizado um estudo durante 60 dias para determinar os efeitos da frequência de alimentação nas medidas de crescimento, composição corporal e atividade enzimática digestiva do juvenil de suruvi (peso médio inicial: 60,19 ± 10,67 g). As unidades experimentais foram tanques circulares de 1,0 m3, estocados com 94 peixes, conectados a um sistema de recirculação. A alimentação foi oferecida durante a fase escura do fotoperíodo (12L:12D), sendo fornecida com os seguintes tratamentos em triplicata: FA1 = uma vez ao dia às 20:00h; FA2 = duas vezes ao dia às 20:00h e 06:00h; e FA3 = três vezes ao dia às 20:00h, 01:00h e 06:00h. Os peixes foram alimentados por uma ração comercial para peixes carnívoros, composta por 42% de proteína bruta, 11% de lipídios, 20% de carboidratos e 4.380 kcal kg-1 de energia bruta em peletes de 6,0 mm. Não foram observadas diferenças significativas nas variáveis de crescimento, composição corporal de proteínas e lipídios e proteases alcalinas e atividade de lipase (p>0,05) entre os tratamentos. No entanto, houve diferenças significativas na atividade da amilase (p<0,05). Nossos resultados demonstraram que os juvenis de suruvi podem ser alimentados de forma sustentável apenas uma vez ao dia.

Feeding frequency in rearing juveniles of suruvi Steindachneridion scriptum / Frequência alimentar na criação de juvenis de suruvi Steindachneridion scriptum

The present study aimed to determine the ideal feeding frequency of feeding for suruvi juvenile. A study was conducted over 60 days to determine the effects of feeding frequency on growth metrics, body composition, and digestive enzyme activity of juvenile suruvi (initial mean weight: 60.19 ± 10.67 g). The experimental units were 1.0 m3 circular tanks, stocked with 94 fish, connected to a recirculating aquaculture system. The feed was offered during the dark phase of the 12:12 photoperiod with the following treatments in triplicate: FF1 = once a day at 20:00h; FF2 = twice a day at 20:00h and 06:00h; and FF3 = three times a day at 20:00h, 01:00h, and 06:00h. The fish fed a commercial carnivorous fish feed comprised of 42% crude protein, 11% lipids, 20% carbohydrates, and 4,380 kcal kg-1 of crude energy in 6.0 mm pellets. At the end of the feeding, no significant differences were observed in the growth variables, body composition of proteins and lipids, and alkaline proteases and lipase activity (p>0.05) between treatments. However, there were significant differences in amylase activity (p<0.05). Our findings demonstrated that suruvi juveniles could be sustainably fed only once a day.(AU)

O presente estudo teve como objetivo determinar a frequência de alimentação para juvenis de suruvi. Foi realizado um estudo durante 60 dias para determinar os efeitos da frequência de alimentação nas medidas de crescimento, composição corporal e atividade enzimática digestiva do juvenil de suruvi (peso médio inicial: 60,19 ± 10,67 g). As unidades experimentais foram tanques circulares de 1,0 m3, estocados com 94 peixes, conectados a um sistema de recirculação. A alimentação foi oferecida durante a fase escura do fotoperíodo (12L:12D), sendo fornecida com os seguintes tratamentos em triplicata: FA1 = uma vez ao dia às 20:00h; FA2 = duas vezes ao dia às 20:00h e 06:00h; e FA3 = três vezes ao dia às 20:00h, 01:00h e 06:00h. Os peixes foram alimentados por uma ração comercial para peixes carnívoros, composta por 42% de proteína bruta, 11% de lipídios, 20% de carboidratos e 4.380 kcal kg-1 de energia bruta em peletes de 6,0 mm. Não foram observadas diferenças significativas nas variáveis de crescimento, composição corporal de proteínas e lipídios e proteases alcalinas e atividade de lipase (p>0,05) entre os tratamentos. No entanto, houve diferenças significativas na atividade da amilase (p<0,05). Nossos resultados demonstraram que os juvenis de suruvi podem ser alimentados de forma sustentável apenas uma vez ao dia.(AU)

Spontaneous spawning of Brazilian sardine in captivity / Desovas espontâneas da sardinha-verdadeira em cativeiro

In one year, 76 first generation (F1) Brazilian sardine Sardinella brasiliensis breeders spawned 84 times spontaneously in captivity. This is the first report for the genus Sardinella. Following the pattern found in the natural environment, the number of spawns, as well as fertilization and hatching rates were higher in spring, summer and fall than in winter. Until now, winter spawning was only presumed to occur in a natural environment. Water temperature, and not photoperiod, was positively correlated with reproductive performance.(AU)

Durante um ano, 76 reprodutores de primeira geração (F1) de sardinha-verdadeira Sardinella brasiliensis desovaram espontaneamente 84 vezes em cativeiro. Esse é o primeiro relato dentro do gênero Sardinella. Seguindo o padrão do ambiente natural, o número de desovas e as taxas de fertilização e eclosão foram maiores na primavera, verão e outono que no inverno. Até o momento, a desova no inverno foi presumida apenas no ambiente natural. A temperatura da água, e não o fotoperíodo, apresentou correlação positiva com o desempenho reprodutivo.(AU)

Maturation, spawning and larviculture of the mullet Mugil liza under laboratory conditions / Maturação, desova e larvicultura da tainha Mugil liza em laboratório

The technical feasibility for the sustainable production of a species depends mainly on the control of reproduction in captivity and the availability of juveniles. Studies were performed with the mullet Mugil liza in the 1980s, however this species was never produced commercially. With the development of aquaculture, the increasing demand for animal protein and the commercial value of the mullet roe, it was necessary to rear this species in the laboratory to produce juveniles in pilot scale. The broodstock, 4 females and 10 males, were kept in an indoor 12 m³ tank. Hormonal inductions were performed with the hormones pituitary extract of carp (PEC) and luteinizing hormone-releasing hormone analog (LHRHa); spawnings occurred between 54-57 h after the hormonal induction. Embryonated eggs of mullets were pelagic and translucent, with an average diameter of 846.29 ± 14.34 µm. The larvae hatched approximately 48 h after spawning with 2.95 ± 0.12 mm. The survival in the larviculture was estimated at 18.75%. Therefore, this study presents the technical methods for the capture, transport, acclimatization, maturation, induced spawning and hatchery of the mullet M. liza in the laboratory.(AU)

A viabilidade técnica para a produção sustentável de uma espécie depende principalmente do controle da reprodução em cativeiro e da disponibilidade de juvenis. Estudos foram realizados com a tainha Mugil liza nos anos 80, entretanto, essa espécie não chegou a ser produzida comercialmente. Com o desenvolvimento da aquicultura, com a crescente demanda por proteína animal, além do valor comercial agregado nas gônadas dessa espécie, surgiu à necessidade de tentar produzi-la em laboratório, desta vez com o objetivo de produzir juvenis em escala-piloto. Os reprodutores, 4 fêmeas e 10 machos, foram mantidos em tanque de 12 m³. As induções hormonais foram realizadas com os hormônios extrato bruto de hipófise de carpa (EBHC) e um análogo do hormônio liberador do hormônio luteinizante (LHRHa); as desovas ocorreram 54-57 h depois da indução hormonal. Os ovos embrionados das tainhas são pelágicos e translúcidos, com um diâmetro médio de 846.29 ± 14.34 µm. As larvas eclodiram aproximadamente 48h após a desova com 2.95 ± 0.12 mm. A sobrevivência desde a estocagem dos ovos até a despesca dos juvenis foi estimada em 18,75%. Sendo assim, este estudo apresenta os métodos técnicos para a captura, transporte, aclimatação, maturação, desova induzida e larvicultura da tainha M. liza em laboratório.(AU)

Maturation, spawning and larviculture of the mullet Mugil liza under laboratory conditions / Maturação, desova e larvicultura da tainha Mugil liza em laboratório

The technical feasibility for the sustainable production of a species depends mainly on the control of reproduction in captivity and the availability of juveniles. Studies were performed with the mullet Mugil liza in the 1980s, however this species was never produced commercially. With the development of aquaculture, the increasing demand for animal protein and the commercial value of the mullet roe, it was necessary to rear this species in the laboratory to produce juveniles in pilot scale. The broodstock, 4 females and 10 males, were kept in an indoor 12 m³ tank. Hormonal inductions were performed with the hormones pituitary extract of carp (PEC) and luteinizing hormone-releasing hormone analog (LHRHa); spawnings occurred between 54-57 h after the hormonal induction. Embryonated eggs of mullets were pelagic and translucent, with an average diameter of 846.29 ± 14.34 µm. The larvae hatched approximately 48 h after spawning with 2.95 ± 0.12 mm. The survival in the larviculture was estimated at 18.75%. Therefore, this study presents the technical methods for the capture, transport, acclimatization, maturation, induced spawning and hatchery of the mullet M. liza in the laboratory.

A viabilidade técnica para a produção sustentável de uma espécie depende principalmente do controle da reprodução em cativeiro e da disponibilidade de juvenis. Estudos foram realizados com a tainha Mugil liza nos anos 80, entretanto, essa espécie não chegou a ser produzida comercialmente. Com o desenvolvimento da aquicultura, com a crescente demanda por proteína animal, além do valor comercial agregado nas gônadas dessa espécie, surgiu à necessidade de tentar produzi-la em laboratório, desta vez com o objetivo de produzir juvenis em escala-piloto. Os reprodutores, 4 fêmeas e 10 machos, foram mantidos em tanque de 12 m³. As induções hormonais foram realizadas com os hormônios extrato bruto de hipófise de carpa (EBHC) e um análogo do hormônio liberador do hormônio luteinizante (LHRHa); as desovas ocorreram 54-57 h depois da indução hormonal. Os ovos embrionados das tainhas são pelágicos e translúcidos, com um diâmetro médio de 846.29 ± 14.34 µm. As larvas eclodiram aproximadamente 48h após a desova com 2.95 ± 0.12 mm. A sobrevivência desde a estocagem dos ovos até a despesca dos juvenis foi estimada em 18,75%. Sendo assim, este estudo apresenta os métodos técnicos para a captura, transporte, aclimatação, maturação, desova induzida e larvicultura da tainha M. liza em laboratório.

Short-term storage of lebranche mullet Mugil liza (Valenciennes, 1836) semen in natura and diluted with CF-HBSS / Armazenamento a curto prazo do sêmen da tainha Mugil liza (Valenciennes, 1836) in natura e diluído com CF-HBSS

The present study aimed to evaluate the activation characteristics of the lebranche mullet spermatozoa in natura and diluted with CF-HBSS for 96h at 4±2°C. The semen was collected from eight wild fish in Florianópolis SC (Brazil) (27°S) in May, during reproductive migration. Three pools of semen were divided into two treatments: in natura and diluted with CF-HBSS 1:3. The semen was activated with seawater (salinity of 34, pH 8.7 and 4±2°C) to determine: motility time, motility rate and sperm cell membrane integrity. Dilution with CF-HBSS 1:3 increased motility time of diluted semen (15- 20% for 6, 12 and 18h). Motility rate was equal to fresh semen for up to 24h of refrigeration and it was 30% higher than in natura semen at 12, 18 and 24h. Cell membrane integrity was maintained in fresh semen up to 6h, and it was 15-20% higher than in natura semen from 6 to 48h (p < 0.05). The use of CF-HBSS as diluent in the ratio 1:3 is recommended for semen refrigeration of lebranche mullet.(AU)

O objetivo do presente estudo foi avaliar em tainha as características de ativação dos espermatozoides in natura e diluídos com CF-HBSS mantidos por 96h a 4±2°C. O sêmen foi coletado de oito peixes selvagens em Florianópolis SC (27°S) em maio, durante a migração reprodutiva. Três pool de sêmen foram divididos em dois tratamentos: in natura e diluído com CF-HBSS 1:3. O sêmen foi ativado com água oceânica (34 de salinidade, pH 8,7 e 4±2°C) para determinar: tempo de motilidade, taxa de ativação espermática e integridade da membrana celular. A diluição com CF-HBSS 1:3 propiciou o aumento no tempo de motilidade do sêmen diluído (15-20% para 6, 12 e 18h); manteve a taxa de motilidade igual ao sêmen fresco por até 24h de refrigeração e foi 30% maior do que em in natura em 12, 18 e 24h; manteve também a integridade da membrana celular igual ao sêmen fresco por 6h e 15-20% maior que em sêmen in natura (p < 0.05) para o período de 6 a 48h. O uso do CF-HBSS como diluidor na proporção 1:3 é recomendado para a refrigeração do sêmen da tainha.(AU)

Short-term storage of lebranche mullet Mugil liza (Valenciennes, 1836) semen in natura and diluted with CF-HBSS / Armazenamento a curto prazo do sêmen da tainha Mugil liza (Valenciennes, 1836) in natura e diluído com CF-HBSS

The present study aimed to evaluate the activation characteristics of the lebranche mullet spermatozoa in natura and diluted with CF-HBSS for 96h at 4±2°C. The semen was collected from eight wild fish in Florianópolis – SC (Brazil) (27°S) in May, during reproductive migration. Three pools of semen were divided into two treatments: in natura and diluted with CF-HBSS 1:3. The semen was activated with seawater (salinity of 34, pH 8.7 and 4±2°C) to determine: motility time, motility rate and sperm cell membrane integrity. Dilution with CF-HBSS 1:3 increased motility time of diluted semen (15- 20% for 6, 12 and 18h). Motility rate was equal to fresh semen for up to 24h of refrigeration and it was 30% higher than in natura semen at 12, 18 and 24h. Cell membrane integrity was maintained in fresh semen up to 6h, and it was 15-20% higher than in natura semen from 6 to 48h (p < 0.05). The use of CF-HBSS as diluent in the ratio 1:3 is recommended for semen refrigeration of lebranche mullet.

O objetivo do presente estudo foi avaliar em tainha as características de ativação dos espermatozoides in natura e diluídos com CF-HBSS mantidos por 96h a 4±2°C. O sêmen foi coletado de oito peixes selvagens em Florianópolis – SC (27°S) em maio, durante a migração reprodutiva. Três pool de sêmen foram divididos em dois tratamentos: in natura e diluído com CF-HBSS 1:3. O sêmen foi ativado com água oceânica (34 de salinidade, pH 8,7 e 4±2°C) para determinar: tempo de motilidade, taxa de ativação espermática e integridade da membrana celular. A diluição com CF-HBSS 1:3 propiciou o aumento no tempo de motilidade do sêmen diluído (15-20% para 6, 12 e 18h); manteve a taxa de motilidade igual ao sêmen fresco por até 24h de refrigeração e foi 30% maior do que em in natura em 12, 18 e 24h; manteve também a integridade da membrana celular igual ao sêmen fresco por 6h e 15-20% maior que em sêmen in natura (p < 0.05) para o período de 6 a 48h. O uso do CF-HBSS como diluidor na proporção 1:3 é recomendado para a refrigeração do sêmen da tainha.