POPULATION BIOLOGY OF SEABOB-SHRIMP Xiphopenaeus kroyeri (Heller, 1862) CAPTURED ON THE SOUTH COAST OF PERNAMBUCO STATE, NORTHEASTERN BRAZIL

This paper aims to describe the population dynamics and to evaluate the stock of the seabob-shrimp Xiphopenaeus kroyeri on the coast of Pernambuco. Sampling was carried out between August/2011 and July/2012 in Sirinhaém, southern coast of Pernambuco. A total of 1201 individuals were analyzed, 673 females and 528 males. Total length (Lt) of females varied from 4.5 to 13.5 cm while the Lt of males ranged between 4.0 and 11.0 cm. The relationship between the Lt and carapace length and Lt and total weight showed negative allometry (males, females and pooled sexes). The slope of the curve "b" was statistically different between males and females for both relationships. Females mature with 8.90 cm. Asymptotic length L∞ was lower for males than for females (12.26 to 14.79 and 10.72 to 11.5 cm, respectively), K was similar between sexes (1.00-2.04 and 1.00-2.63 cm/year-1 respectively) as well as the longevity and size at 1st capture (1.50 to 1.97) years and 7.9 to 8.9 cm for males and females, respectively). The results indicate that X. kroyeri in the region is not overexploited for males, however considering females and pooled sexes the stock is near to being fully exploited.Este trabalho tem por objetivo descrever a dinâmica populacional e avaliar o estoque do camarão sete-barbas Xiphopenaeus kroyeri do litoral de Pernambuco. As coletas foram realizadas entre os meses de agosto/2011 a julho/2012 em Sirinhaém, litoral sul de Pernambuco. Foram analisados 1201 exemplares, sendo 673 fêmeas e 528 machos. Comprimento total (CT) das fêmeas variou de 4,5 a 13,5 cm enquanto o CT dos machos variou entre 4,0 e 11,0 cm. As relações entre o CT e comprimento da carapaça e o CT e peso total apresentaram alometria negativa (machos, fêmeas e sexos agrupados). O declive da curva "b" foi estatisticamente diferente entre machos e fêmeas para ambas relações. Fêmeas maturam com 8,90cm. O comprimento assintótico L∞ foi menor para os machos do que para as fêmeas (10,72-11,5 e 12,26-14,79 cm respectivamente), o K foi similar entre sexos (1,00-2,04 e 1,00-2,63cm/ano-1 respectivamente) assim como a longevidade e tamanho de 1ª captura (1,50-1,97anos e 7,9 - 8,9 cm para machos e fêmeas, respectivamente). Os resultados indicam que o estoque de X. kroyeri na região não se encontra sobreexplorada para os machos, entretanto considerando as fêmeas e sexos agrupados o recurso se encontra próximo do limite máximo de exploração

Application of von Bertalanffy growth curves in a Farfantepenaeus paulensis (Decapoda, Penaeidae) captive broodstock

The aim off the present study was to analyze the growth Farfantepenaeus paulensis juveniles captured in the Patos Lagoon Estuary (Rio Grande do Sul, Brasil), by fitting the von Bertalanffy growth model. Estuary-caught juveniles with mean weight (± SD)of 9.7 ± 2.3 and 7.5 ±2.3g for mamales and males, respectively, werw mantained indoors at a density of 7.3 srimp / m²for 279 days by which time they had exceeded the minimum size for reproduction (32.50 ± 5.14g for femalis and 21.55 ±2.15g for males). Modal progression analysis and the von Bertalanffy growth model were used to estimative weigth (W) and carapace length (Lc)growth curver for females and males, as follows: The growth curves were coherent with published information for F. paulensis and other panaeids, and provide a tool for aquaculture management and research

Performance of Farfantepenaeus paulensis (Pe´rez-Farfante, 1967) broodstock in tanks with sand and hard substrate

This study evaluated the reproductive performance, physical condition and tissue biochemical composition of wild-caught Farfantepenaeus paulensis kept for 50 days in maturation tanks provided with sand or hard substrate. The use of sand in F. paulensis maturation tanks had limited impact on the performance and biochemical composition of broodstock. Females in the hard-bottom tank produced more spawns and more eggs in total, but those kept in the presence of the sand substrate produced a larger number of nauplii because an improvement in mating success was observed. An increased survival of females was also related to the presence of the sand substrate, which agrees with improvements in water quality and the physical condition of females. On the other hand, sourcing mature females was more di⁄- cult and time consuming in sand-bottom tanks. The decision on whether or not to use sand substrates in F. paulensis maturation tanks must take into account not only productivity and animal welfare but also considers ease of operation and costs. These ￠ndings may have implications for the design of maturation systems for closed thelycum species

Influence of artificial insemination on the reproductive performance of Farfantepenaeus paulensis in conventional and unisex maturation systems

The application of artificial insemination techniques as a way to overcome the lack of mating of the closed thelycum Farfantepenaeus paulensis under large scale conditions is reported. The performance of artificially inseminated females (49.4 F11.6 g) maintained in conventional versus unisex maturation systems was compared. Groups of unilaterally eyestalk-ablated females were artificially inseminated with one compound spermatophore soon after molting. The percentage of fertilized spawns increased from 26% before the use of artificial insemination to 57% afterwards. The reproductive performance of inseminated females held in conventional or unisex maturation systems showed no significant differences. Artificial insemination was considered a practical approach to overcome the lack of mating of F. paulensis under large-scale conditions with acceptable reproductive performance. The results also indicate the possibility of holding females separately from males, which could mean significant improvements in maturation systems through the increase in the stocking density of spawning female

Effect of different food items on the survival and growth of Farfantepenaeus paulensis (Pérez-Farfante 1967) postlarvae

The effect of different food items on growth and survival was assessed in four feeding experiments conducted consecutively using distinct Farfantepenaeus paulensis (Pérez-Farfante) postlarval growing stages: (1) PL1–PL4 (i.e. from postlarvae 1-day old to postlarvae 4 days old); and (2) PL4–PL10; (3) PL10–PL18 and (4) PL18–PL30. For each trial, 10 feeding treatments were tested in triplicate: Unf, unfed shrimp; Tt, Tetraselmis chuii; Ch, Chaetoceros calcitrans; C, commercial diet; AC, decapsulated Artemia cysts; C+Ph, commercial diet and phytoplankton combination; FA, frozen Artemia nauplii; A, live Artemia nauplii; A+Ph, Artemia nauplii and phytoplankton combination and Mix, mixture of phytoplankton, live Artemia nauplii and commercial diet. Postlarvae feed phytoplankton (i.e. Tt or Ch) exclusively exhibited low growth and survival. The best results for growth and survival were observed in the A, A+Ph and Mix treatments. Frozen Artemia nauplii was found to be suitable for younger postlarvae (PL1–10), whereas AC may be offered from PL4 to PL30. In general, the present findings indicated that even at an early postlarval stage, F. paulensis presents a high degree of carnivory, and a diet containing Artemia is recommended

Effects of feeding plant material on growth and survival of pink shrimp farfantepenaeus paulensis

Efeito da alimentação com vegetais no crescimento e sobrevivência do camarão-rosa Farfantepenaeus paulensis Quantidades significativas de material vegetal têm sido encontradas no conteúdo estomacal de juvenis do camarão-rosa Farfantepenaeus paulensis que habitam o estuário da Lagoa dos Patos no sul do Brasil. Um experimento em laboratório, com duração de 20 dias, foi realizado para avaliar a sobrevivência e o crescimento de juvenis de F. paulensis (0.84 ± 0.24 g; peso médio inicial ± desvio padrão) alimentados com três diferentes dietas vegetais. Os tratamentos alimentares foram: (1) macroalga Enteromorpha sp. (Entero); (2) gramínea aquática Ruppia maritima (Ruppia); (3) marisma Spartina sp. (Spartina); (4) ração comercial (CD); e (5) sem alimento (Unfed). O crescimento e a sobrevivência dos camarões submetidos às dietas vegetais foram similares aos resultados apresentados pelos camarões mantidos sem alimentação (Unfed). Crescimento e sobrevivência significativos somente foram observados no tratamento com ração comercial (CD). Os resultados indicaram que os vegetais testados não são capazes de suportar o crescimento e a sobrevivência de juvenis de F. paulensis quando utilizados como única fonte de alimentação. Sugere-se ainda, que a ingestão destes vegetais pelo F. paulensis, durante sua fase estuarina, tenha como objetivo o consumo de organismos que se desenvolvem aderidos à estrutura destes vegetais.Significant amounts of plant material have been detected in the stomach contents of Farfantepenaeus paulensis juveniles inhabiting the Patos Lagoon estuary, southern Brazil. A 20-day long laboratory feeding experiment was performed to evaluate survival and growth of F. paulensis juveniles (0.84 ± 0.24 g; mean initial body weight ± sd) fed on three distinct plant diets. The feeding treatments consisted of: (1) macroalga Enteromorpha sp. (Entero treatment); (2) seagrass Ruppia maritima (Ruppia treatment); (3) saltmarsh Spartina sp. (Spartina treatment); (4) commercial diet (CD treatment); and (5) without food (Unfed treatment). Overall, growth and survival of juveniles submitted to plant treatments were similar to the Unfed treatment. Significant growth and survival were observed only in the CD treatment. Results indicated that the plant material tested were not capable to support survival and growth of F. paulensis when offered as the sole food source. It could be suggested that the consumption of this plant material by F. paulensis during their estuarine phase might be focused on the attached organisms

Feeding rhythms and diet of Farfantepenaeus paulensis under pen culture in Patos Lagoon estuary, Brazil

The feeding habits of Farfantepenaeus paulensis under pen culture in the Patos Lagoon estuary (Brazil) were studied. A total of 1074 shrimp had their stomach contents analyzed. Samples were taken bi-hourly over a 24 h period at about 10 day intervals during 2 months. F. paulensis did not exhibit strict feeding periodicity (except at D21–22 and D32–33). Thus, the offering of feed pellets during daylight is recommended but the rates of feeding must be further investigated. F. paulensis showed an omnivorous feeding behavior. Despite daily supply of feed pellets, natural food comprised the major part of the shrimp stomach contents. Among prey organisms, polychaetes and tanaids were the main groups recorded. Consumption of detritus and plant material decreased as shrimp grew. Intake of feed pellets increased significantly in the second month of culture (i.e. 5 g mean shrimp weight), thus it might be possible to reduce the initial input of commercial feed

Estudo comparativo da histologia ovariana de Farfantepenaeus paulensis com e sem ablação do pedúnculo ocular após a desova

Submitted by Thainã Moraes ([email protected]) on 2012-12-07T23:12:47Z No. of bitstreams: 1 A COMPARATIVE STUDY OF THE OVARIAN HISTOLOGY OF EYESTALK ABLATED AND.pdf: 1076323 bytes, checksum: a8ddddfe68e7bdbba7fd74f65d403c01 (MD5)Approved for entry into archive by Michele Fernanda([email protected]) on 2012-12-20T02:01:29Z (GMT) No. of bitstreams: 1 A COMPARATIVE STUDY OF THE OVARIAN HISTOLOGY OF EYESTALK ABLATED AND.pdf: 1076323 bytes, checksum: a8ddddfe68e7bdbba7fd74f65d403c01 (MD5)Made available in DSpace on 2012-12-20T02:01:29Z (GMT). No. of bitstreams: 1 A COMPARATIVE STUDY OF THE OVARIAN HISTOLOGY OF EYESTALK ABLATED AND.pdf: 1076323 bytes, checksum: a8ddddfe68e7bdbba7fd74f65d403c01 (MD5) Previous issue date: 2002The effect of unilateral eyestalk ablation on ovarian histology of Farfantepenaeus paulensis after spawning was evaluated in the present study. Wild females were captured in deep-sea waters of southern Brazil (27 o S) and randomly divided in two groups: unilaterally eyestalk ablated and unablated (intact) females. A total of six eyestalk ablated and five unablated females were sampled after spawning in separated tanks. Morphological variables were recorded and ovaries were histologically evaluated according to oocyte type and diameter. In the ovarian tissue of unablated females, basophilic oocytes (48.8 ± 18.7 µm) were dominant (99.7 ± 0.6%), with presence significantly lower in the ablated females (93.5 ± 13.8%). Larger acidophilic oocytes (114.9 ± 16.9 µm), with yolk granules in the cytoplasm, were detected only in the ovaries of ablated females. The significantly higher occurrence of atretic oocytes (4.8 ± 10.3%) is another distinguishable feature in the ovaries of ablated females compared with the unablated ones. The presence of advanced yolky oocytes in ablated females just a few hours after spawning, may indicate the effect of eyestalk ablation on the precocious rematuration of the ovary. The higher number of atretic oocytes in the ovary of ablated females could be relevant to their reproductive performance, as they represent a percentage of oocytes that were not released in the spawning process. The present results of the histology of the ovaries reveal the existence of substantial differences in the cell arrangement of ablated and unablated females after spawning. The results also demonstrate the effects of unilateral eyestalk ablation in the reproductive cycle of F. paulensis under laboratory conditions.O presente estudo avalia o efeito da ablação do pedúnculo ocular na histologia gonadal de Farfantepenaeus paulensis após a desova. Fêmeas selvagens foram capturadas em águas profundas na região sul do Brasil (27 o S), sendo divididas aleatoriamente em dois grupos: com ablação unilateral do pedúnculo ocular e sem ablação (intactas). Um total de seis fêmeas sem pedúnculo e cinco intactas foram amostradas após suas desovas individualizadas. Após avaliação dos parâmetros morfológicos, os ovários foram histologicamente analisados quanto ao tipo e diâmetro dos ovócitos. Nos ovários das fêmeas intactas, os ovócitos basófilos (48,8 ± 18,7 µm) foram dominantes (99,7 ± 0,6%), sendo sua presença significativamente inferior (93,5 ± 13,8%) em fêmeas sem pedúnculo. Ovócitos acidófilos de maior tamanho (114,9 ± 16,9 µm), com citoplasma granuloso, foram observados apenas nos ovários das fêmeas sem pedúnculo. A ocorrência elevada de ovócitos em atresia (4,8 ± 10,3%) foi outra característica dos ovários das fêmeas sem pedúnculo, quando comparados aos das fêmeas não-abladas. A presença de ovócitos em desenvolvimento mais avançado em fêmeas sem pedúnculo, algumas horas após a desova, parece indicar o efeito da ablação do pedúnculo ocular na maturação precoce dos ovários. A alta incidência de ovócitos atrésicos em fêmeas sem pedúnculo pode ser relevante para seu desempenho reprodutivo, já que representam uma porcentagem de ovócitos não liberados no momento da desova. Pode-se concluir que a histologia dos ovários permite revelar diferenças significativas no arranjo celular de fêmeas sem pedúnculo e intactas. Os resultados demonstram o efeito da ablação do pedúnculo ocular no desempenho reprodutivo de F. paulensis em laboratório