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Genetic population structure of spiny lobster Palinurus delagoae in the south-western Indian Ocean, and the evolutionary history of PalinurusGopal, Keshni 03 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: This study investigated the evolution of the genus Palinurus at the higher and lower
taxonomic levels. The population genetics of the spiny lobster, Palinurus delagoae, was
investigated by making use of a portion of the mitochondrial DNA (mtDNA) control
region (547 base pairs) that was sequenced for 285 lobsters from the southeastern coast of
Africa (six sites) and 49 lobsters from Walters Shoals (one site), a submerged seamount
on the Madagascar Ridge. Lobsters from these two areas shared no haplotypes and
differed by at least 27 mutational steps. An analysis of molecular variance showed
significant genetic partitioning, and pairwise comparisons suggested that lobsters from
Walters Shoals are distinct from those of other sampling areas. Along the south east
African coastline there was shallow genetic partitioning between four southern sites
(South Africa) and two northern (Mozambique) sites, suggesting two Management Units
along the African coast. Female gene flow along the African coast may be propagated by
larval dispersal in the Mozambique and Agulhas Currents and counter-current migrations
by benthic juveniles along the shelf, but the mtDNA data strongly suggest that larvae at
Walters Shoals have been, or are currently still retained by other oceanographic
processes. The magnitude of mtDNA divergence among lobsters from the southeastern
coast of Africa and those at Walters Shoals, together with the absence of any shared
haplotypes between these regions, strongly suggested that these two taxa represent
distinct species. The molecular data of the large subunit ribosomal RNA, 16S rRNA (481
bp), and cytochrome oxidase subunit I, COI (520 bp) were then used for a higher level
phylogenetic analysis of the genus. A total of 33 individuals (five representatives from
each of the six species), and two outgroups (Projasus parkeri and Palinustus unicornutus), were subjected to maximum parsimony, maximum likelihood and Bayesian
inference analyses. All analyses were conducted on both the separate data sets as well as
a combination of the two genes. Bootstrap analyses of the 16S rRNA data resulted in
>70% support for the monophyly of all six Palinurus species but no support could be
obtained for any of the interspecific associations. Likewise, individual analyses of the
COI gene resulted in strong support for the monophyly of the species. The combined
data (parsimony analyses) increased the resolution considerably and apart from the
monophyly of all six species, good bootstrap support was also obtained for associations
among species. The topology for the maximum likelihood analyses displayed a more
resolved and well supported tree when the basal ingroup taxon P. elephas was used to
root the tree. The combined Bayesian analyses did not result in a well resolved topology
and no significant posterior probabilities could be obtained reflecting the associations
among species. / AFRIKAANSE OPSOMMING: Hierdie studie het die evolusie van die genus Palinurus by hoë en laer taksonomiese
vlakke ondersoek. Die bevolkingsgenetika studie op die kreef, Palinurus delagoae, is
ondersoek deur gebruik te maak van 'n gedeelte van die mitokondriale (mtDNA)
kontrole-area (547 basispare) waarvan die volgorde bepaal is vir 285 krewe van die
suidoos-kus van Afrika (afkomstig van ses verskillende gebiede) en 49 krewe afkomstig
van Walters Shoals (een gebied), 'n ondersese berg op die Madagaskar Rand. Krewe van
hierdie twee areas deel geen haplotipes nie en verskil met ten minste 27 mutasiestappe.
'n Analise van die molekulêre variansie toon dat daar 'n beduidende genetiese verdeling
tussen die twee groepe is en 'n gepaarde vergelyking toon dat krewe afkomstig van
Walters Shoals verskil beduidend van krewe uit ander gebiede. Volgens die vlak
genetiese verdeling tussen die vier suidelike (Suid-Afrika) en twee noordelike
(Mosambiek) gebiede van die suidoos-kus van Afrika wil dit voorkom of daar twee
bestuurseenhede langs die kuslyn van Afrika is. Vroulike geenvloei langs hierdie kuslyn
kan dalk bevarder word deur larwale verspreiding in die Mosambiek- en Agulhas-
Seestrome en teenstroom migrasie van jong bodemwonende krefies op die kontinentale
plaat. Die mtDNA data stel egter voor dat kreeflarwes by Walters Shoals deur ander
oseanografiese prosesse steeds (of tot onlangs toe) behou word. Die grootte van mtDNA
divergering tussen krewe van die suidoos-kus van Afrika en die by Walters Shoals, sowel
as die afwesigheid van enige gemeenskaplike haplotipes tussen die twee gebiede, toon
met beduidende sekerheid aan dat hierdie twee taksa twee unieke spesies verteenwoordig.
Die molekulêre data van die 16S-rRNA (481bp) van die groot ribosomale-subeenheid en die sitochroom oksidase subeenheid, COI (520bp) is gebruik om 'n hoër resolusie
filogenetiese analise van die genus te bepaal. Data van 33 individue (vyf individue uit
elk van die ses spesies) en twee buitegroepe (Projasnus parkeri en Palinustus
uniconutus) is geanaliseer deur gebruik te maak van die maksimum-parsimonie, die
maksimum-waarskynlikheid en die Bayes-inferensie metodes. Alle analises is uitgevoer
op beide die afsonderlike datastelle sowel as op die gekombineerde data van die twee
gene. Analise van die 16S-rRNA data deur die skoenlusmetode (steekproefhersteekproef-
metode) toon meer as 70% steun vir die monofilie van al ses Palinurus
spesies maar dit toon geen steun vir enige van die interspesifieke assosiasies nie. Net so
toon individuele analise van die COI geen beduidende steun vir die monofilie van die
spesies. Die gekombineerde data (parsimonie) het 'n aansienlike verhoging in die
resolusie teweeg gebring en behalwe vir die monofilie van al ses die spesies was daar ook
goeie steun deur die skoenlusmetode vir die assosiasie tussen spesies verkry. Die
topologie vir die maksimum-parsimonie het 'n goed gesteunde en hoër resolusie boom vir
die gekombineerde datastel (sonder die buitegroepe) getoon. Die gekombineerde Bayesanalise
het nie 'n soortgelyke boom opgelewer nie en die assosiasie tussen die spesies is
nie ondersteun nie aangesien geen beduidende a posteriori-waarskynlikheid verkry kon
word nie.
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The fishery and biology of the rock lobster Jasus tristani at the Tristan da Cunha Islands groupGlass, James Patrick January 2014 (has links)
Thesis submitted in fulfilment of the requirements for the degree
Master of Technology: Oceanography
in the Faculty of Applied Sciences
at the Cape Peninsula University of Technology
2014 / The Tristan lobster Jasus tristani is distributed among several isolated islands and
submerged seamounts in the South East Atlantic Ocean. This species occurs only at the
Tristan da Cunha group, a British Overseas Territory and the World’s most remote inhabited
island, and in international waters at Vema Seamount 1680 km ENE of Tristan. All these
populations are exploited commercially. The catch, processing and export of J. tristani is the
most important economic activity for the inhabitants of Tristan da Cunha, providing the
livelihood of many families and accounting for approximately 80% of the Island’s revenue.
Sustainable harvesting of this valuable resource requires accurate long-term data on catch
and effort, as well as information on the most important biological parameters such as
growth, recruitment, moulting and reproductive cycles. This information is critical for robust
assessments and management strategies. This thesis describes the history of the lobster
fishery at the Tristan da Cunha island group, reporting on catches and trends in Catch Per
Unit Effort between 1967 and 2010. A total of 247,014 lobster samples, both sexes
combined, was sampled for size composition and sex ratios, as well as 1,526 lobsters for
length/weight relationships, between 1997 and 2010. This confirms earlier findings that
females have broader and heavier tails than males for the same carapace length (CL).
Results show that males dominate catches at all islands, and their average size was larger
than that of females (83.5 ± 14.46 versus 73.4 ± 8.64 mm CL, respectively). Inter-island
differences in lobster population structure appear to be caused by differences of food
availability as well as in density-dependent growth and survival of young lobsters. The largest
lobsters were found at Gough Island (87.2 ± 15.13 mm CL), and the smallest at Inaccessible
island (73.2 ± 11.39 mm). Tristan was the next largest to Gough Island (84.0 ± 12.56 mm)
followed by Nightingale island (78.2 ± 11.33 mm). Lobsters caught inshore were larger than
those caught offshore, although this may be related in part to differences in catches between
fishing gear types.
This study showed that fecundity increases in a linear manner with CL, and although larger
lobsters clearly produce more eggs than smaller ones, the gain in fecundity is not as great as
in some lobster species where fecundity is more closely associated with weight. The study
showed no significant differences in egg size between islands, or between large and small
females at one island. The egg production per gram of body weight and mean egg diameter
both seem to be less than reported in an earlier study in the 1990s. While it seems likely that
this is due to differences in the way in which samples were collected (with only stage 2 ova
collected and measured in this study), the possibility of a decline in fecundity needs to be
investigated further.
A range of management measures have been developed over the history of the fishery, and
important current measures include an annual total allowable catch (TAC) for each island,
minimum size limits, and a closed season timed to protect egg-bearing females. The fishery
has recently been awarded certification by the Marine Stewardship Council. The study has
confirmed that current conversion factors are broadly correct and that different size limits
established for each island are justified. Concern is raised, however, by the fall in catch per
unit effort and the mean size of lobsters at the three northern islands over the past 7 years.
These trends will need to be closely monitored.
There are still many uncertainties over key parameters such as growth and recruitment and
the intention is to increase the knowledge base and our understanding of the dynamics of the
lobster stock. A research plan has been developed, so that progress can be monitored
through the gradual implementation of scientifically defendable fisheries management
procedures and increased research and monitoring capacity.
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Molecular phylogeny and population genetic structure of the shallow-water spiny lobster Panulirus homarus in the South West Indian Ocean region : implications for management.Reddy, Mageshnee Mayshree. 29 November 2013 (has links)
The scalloped spiny lobster, Panulirus homarus has a subspecies trio that are widely
distributed in shallow-water habitats in the South West Indian Ocean. Subspecies are
defined by differences in colour and abdominal sculptural pattern. A red variety with the
megasculptural carapace pattern, P. h. rubellus is distributed along the south east coast
of Africa and Madagascar, where they are endemic. Along the African coast P. h.
rubellus stocks traverse political boundaries, Mozambique and South Africa. This
project aimed to facilitate regional fisheries management of shared stocks by employing
genetic tools to determine whether stocks (or populations) are indeed shared between
countries. Lobster samples were collected from seven localities throughout the east
African coast. The mitochondrial cyctochrome c oxidase subunit 1 region was
sequenced to assess the genetic diversity 1) between different subspecies, P. h. homarus
and P. h. rubellus and 2) between populations of P. h. rubellus across its African
distribution range. Using DNA barcoding methods, genetic diversity was also found
between morphologically distinct subspecies, Panulirus homarus homarus and P. h.
rubellus which differed genetically by ca. 2-3% in sequence divergence. Both
subspecies were monophyletic relative to the out-group taxa and formed well supported
sister clades (BI: 1.00, ML: 93%, P: 100%, NJ: 100%). The distribution of P. h.
rubellus along the African coast occurs adjacent to different current regimes and
therefore varied larval transport modes (i.e. Agulhas Current and inshore countercurrents
along the Eastern Cape). This may have driven the formation of subpopulations
(ΦPT = 0.104, p = 0.010) which differ by ca. 1.7% in sequence difference. The pattern of
gene flow of populations of P. h. rubellus lends support to the Agulhas Current being a
major mode of larval transport as well as corroborates previous abundance and
distribution records. Time since population expansion estimates for the P. h. homarus
and P. h. rubellus subspecies as well as for the P. h. rubellus subpopulations dated back
to the mid-Holocene Epoch in accordance with a warmer, more stable marine
environment. Genetically distinct subspecies of P. homarus as well as differentiated
subpopulations of P. h. rubellus calls for a re-visit of the current collective management
of P. homarus as well as P. h. rubellus as a single genetic stock along the south east
African coast. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2013.
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Larval Release Rhythms and Larval Behavior of Palinurid Lobsters a comparative studyZiegler, Tracy Ann. January 2007 (has links) (PDF)
Thesis (Ph. D.)--Duke University, 2007. / Includes bibliographical references.
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Engorda de juvenis recentes da lagosta espinhosa panulirus laevicauda (latreille, 1817) alimentados com raÃÃo comercial para camarÃo marinho e os moluscos mytella falcata e perna perna, em condiÃÃes de laboratÃrio / Fattening of juvenile spiny lobster recent panulirus laevicauda (Latreille, 1817) fed a commercial diet for shrimp and clams Mytella falcata and leg leg in laboratoryCarlos Henrique dos Anjos dos Santos 19 December 2006 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A lagosta à um recurso pesqueiro de grande importÃncia econÃmica
para o Estado do CearÃ. Esta atividade teve seu inÃcio na dÃcada de 50 e de lÃ
para cÃ, vÃrios tipo de embarcaÃÃes e artes-de-pesca foram utilizadas para a
captura deste recurso. No entanto, com o inÃcio da exploraÃÃo deste crustÃceo,
veio consequentemente a diminuiÃÃo dos estoques naturais, e isto, devido a
grande demanda do setor pelo produto, que forÃou dessa maneira a exploraÃÃo
deste recurso. Atualmente, esta atividade esta em forte declÃnio e uma das
formas para reverter esse quadro seria atravÃs da aqÃicultura, ou seja, do
cultivo de nossas espÃcies em cativeiro. O presente trabalho teve como
objetivo de avaliar o desenvolvimento de juvenis recentes da lagosta espinhosa
Panulirus laevicauda, alimentadas com os moluscos Perna perna, Mytella
falcata e raÃÃo comercial para camarÃo marinho + biomassa de Artemia sp.,
em condiÃÃes de laboratÃrio. Este experimento foi realizado nas instalaÃÃes do
Centro de Tecnologia em Aquicultura da Universidade Federal do CearÃ, em
um perÃodo de 122 dias. Este trabalho foi dividido em trÃs tratamentos
(tratamento A â P. perna, tratamento B â M. falcata e tratamento C â raÃÃo
comercial + biomassa de Artemia sp.) com quatro repetiÃÃes cada. A taxa de
densidade inicial utilizada foi de um indivÃduo por repetiÃÃo. Os alimentos foram
ofertados de acordo com 10% da biomassa dos indivÃduos. Durante o
experimento foram realizadas as anÃlises bromatolÃgicas dos alimentos, sendo
verificados as quantidades de proteÃnas, lipÃdeos, cinzas, carboidratos e
umidades. Os parÃmetros fÃsico-quÃmicos (pH, temperatura e salinidade) foram
observados diariamente e as biometrias (peso, comprimento do cefalotÃrax e
total) mensalmente. Diariamente, se observava a ocorrÃncia de mudas nos
tratamentos com os seus respectivos dias. ApÃs o tÃrmino do experimento os
parÃmetros fÃsico-quÃmicos, os dados biometricos, os nÃmeros de mudas, as
freqÃÃncias de mudas e as taxas de sobrevivÃncia foram analisadas por testes
estatÃsticos. Os testes estatÃsticos utilizados foram o Kolmogorov-Smirnov e o
teste âtâ de Student (parÃmetros fÃsico-quÃmicos), a AnÃlise de VariÃncia
(ANOVA) e se necessÃrio o teste de Tukey (biometrias, nÃmero de mudas,
perÃodo de intermudas) e o teste do Qui-quadrado de Pearson (sobrevivÃncia),
respectivamente. Os nÃveis de significÃncia utilizado nos testes estatÃsticos
foram de  = 0,05. Os parÃmetros fÃsico-quÃmicos deste trabalho mostraram
valores mÃnimos, mÃximos e mÃdios muito prÃximos entre si. Com a realizaÃÃo
do teste de Kolmorogov-Smirnov, o mesmo mostrou que o pH, temperatura e
salinidade, atenderam a suposiÃÃo de normalidade. Ao comparar estes
parÃmetros com o teste âtâ de Student, foi verificado que nÃo houve diferenÃa
estatÃstica significativa entre os tratamentos (P > 0,05). Ao analisamos os
resultados do crescimento em peso (g), ganho de peso (g), crescimento do
comprimento do cefalotÃrax (mm) e do comprimento total (mm) em valores
brutos, observamos que as lagostas do tratamento C apresentaram um ligeiro
desenvolvimento em comparaÃÃo aos tratamentos A e B (P > 0,05). Por outro
lado, os ganhos de comprimento do cefalotÃrax (mm) e do ganho de
comprimento total (mm), apresentaram alternÃncia entre os tratamentos, sendo
que os valores destes ganhos foram um pouco menor para o tratamento C (P >
0,05). Todos os incrementos aqui analisados seguiram as seguintes
seqÃÃncias, o tratamento B apresentou-se um pouco melhor em relaÃÃo aos
tratamentos A e C (P > 0,05). As anÃlises bromatolÃgicas da dieta do
tratamento B apresentaram valores de proteÃna, lipÃdeos e carboidratos mais
altos em relaÃÃo ao tratamento C que apresentou os valores menores entre as
dietas, respectivamente. As lagostas do tratamento A, B e C, apresentaram
praticamente o mesmo nÃmero de mudas e o perÃodo de intermudas (P > 0,05).
A taxa de sobrevivÃncia foi tambÃm bastante prÃxima uma da outra, chegando
em alguns tratamentos serem praticamente iguais (P > 0,05). Concluirmos que
os alimentos utilizados neste experimento podem ser utilizados na alimentaÃÃo
de juvenis recentes da lagosta espinhosa P. laevicauda. Outro resultado
animador obtido neste trabalho foi à aceitaÃÃo pela lagosta da dieta artificial, jÃ
que uma das grandes problemÃticas em um projeto piloto de cultivo de nossas
espÃcies, seriam a aceitaÃÃo das mesmas por uma dieta peletizada. / The spiny lobster represents an important economic fisheries resource in
Ceara State, contributing to the generation of profitable activity and
employment. Due to the exploitative and destructive fishing practices, along
with the degradation of the natural habitat from pollution and human activity, a
precipitous decline in the wild populations has occurred. This activity had begun
by 1950s. Since then, different types of vessel and gears were used to catches
of this resource. However, with the catches of this crustacean and the growing
market demand, as a consequence, decrease natural stock. At present, this
activity have had a strong decrease and one of the few ways to expand
production is through aquaculture or culture of these species in captivity. In view
of this decline, the objective of the present study is to analyze the development
of early juvenile spiny lobster Panulirus laevicauda fed on molluscs Perna
perna, Mytella falcata and commercial marine shrimp ration + Artemia sp.
biomass, in laboratory condition. This experiment was carried out in the
Aquaculture Technology Center, Federal University of Ceara in a 122 days
feeding trial. The juveniles were submitted to three treatment (treatment A â P.
perna, treatment B â M. falcata and treatment C â commercial ration + Artemia
sp. biomass) repeated 4 times. Initial density used was one individual per
container. The feed rate was 10 % of the individual biomass. During the
experiment bromatological analyses of the feed was done, verifying protein,
lipids, ash, carbohydrate and humidity. The chemical and physical parameters
of the experimental water (pH, temperature and salinity), were measured daily
and the juveniles were measured verifying cephalotorax and total length and
weighed at each 30 days of culture. At the end of the experiment, chemical and
physical parameters, biometric data, number and frequency of molts per
individual, survival rate were analyzed for the determination of statistical tests.
Analysis with Kolmogorov-Smirnov the Student Test (chemical and physical
parameters), Analysis of Variance (ANOVA) and if necessary the Tukey Test
(biometric data, number and frequency of molts and intermoult per individual)
and test Qui-Quadrado of Pearson (survival rate), respectively. For the
statistical tests, it has been used  = 0,05 significance level. In this work
chemical and physical parameters showed minimum, maximum and medium
value much close among the treatments. Analysis with Kolmogorov-Smirnov
showed that pH, temperature and salinity, attended normal supposition. These
parameters showed no significant differences (P > 0,05) with the Student Test
during the cultures among the treatments. After finished the experiment,
chemical and physical parameters, biometric data, number and frequency of
molts per individual, survival rate were analyzed for the determination of
statistical tests. The results of gross weight (g) and cephalotorax (mm) and total
(mm) length of spiny lobsters of treatment C showed a slight development
compared to spiny lobsters of treatments A and B (P > 0,05). On the other
hand, increment of cephalotorax (mm) and total (mm) length, showed
alternation among the treatments. The value of these increments were slight
lower for the treatment C (P > 0,05), respectively. The results of increments in
treatment B showed slight better in relation to the treatment A and C(P > 0,05)
respectively. The bromatological analyze of food in treatment B showed higher
protein, lipid and carbohydrate value and the diet of treatment C showed lower
value, respectively. The spiny lobster of treatment A, B, and C showed almost
the same number of moults and intermoult periods (P > 0,05). The survival rate
was also closed each other, and in some treatments almost the same (P >
0,05). We concluded that early juvenile spiny lobster P. laevicauda can be fed
on diets used in this experiment. In addition the individuals accepted
commercially formulated shrimp feeds. This fact contribute to the development
of the methodology on the culture of lobsters, with speculation on the possible
adaptations that can be useful to the final development of commercially incomeproducing
units.
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Desenvolvimento de juvenis recentes de lagosta espinhosa Panulirus argus (Latreille, 1804) (Crustacea, Decapoda, Palinuridae) submetidos a diferentes temperaturas em condiÃÃes de laboratÃrio / Recent Development of juvenile spiny lobster Panulirus argus (Latreille, 1804) (Crustacea, Decapoda, Palinuridae) under different temperatures under laboratory conditionsJullyermes AraÃjo LourenÃo 16 December 2006 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Devido a grande importÃncia econÃmica da lagosta espinhosa para a
RegiÃo Nordeste, principalmente para o Estado do Cearà e tambÃm pela
sobrexplotaÃÃo em que esse crustÃceo encontra-se atualmente, o Centro de
Tecnologia em AqÃicultura do Departamento de Engenharia de Pesca da
Universidade Federal do CearÃ, vÃm realizando pesquisas com o intuito de
contribuir para o estabelecimento de uma metodologia bÃsica de cultivo para
lagosta em laboratÃrio. Dessa forma, o objetivo da presente pesquisa foi verificar a
influÃncia de cinco diferentes temperaturas no desenvolvimento de juvenis
recentes da lagosta espinhosa Panulirus argus em laboratÃrio, sendo estas
delineadas da seguinte forma: 24, 26, 28, 30 e 32 ÂC, resultando em cinco
tratamentos com quatro repetiÃÃes, totalizando 20 indivÃduos, sendo dado um
carÃter inteiramente casualizado ao experimento. Os juvenis foram coletados em
marÃs baixas de sizÃgia (- 0,1 e 0,0 m) atravÃs de mergulho e puÃÃ plÃstico nas
imediaÃÃes da Ponte dos Ingleses, Praia de Iracema, Fortaleza, CearÃ, Brasil,
onde apresentaram inicialmente peso mÃdio, comprimento mÃdio do cefalotÃrax e
comprimento mÃdio total de 2,680 g; 13,8 mm e 40,4 mm, respectivamente. O
desenvolvimento dos indivÃduos foi determinado atravÃs de anÃlises e
observaÃÃes dos parÃmetros de crescimento em peso e comprimento, nÃmero de
mudas, perÃodo de intermudas e taxa de sobrevivÃncia. O procedimento
experimental foi realizado em cinco caixas de polietileno medindo 37 x 55,5 cm,
com capacidade para 30 L de Ãgua, cada. Foram colocados filtros biolÃgicos e aeraÃÃo artificial para melhorar a qualidade e a taxa de oxigÃnio dissolvido da
Ãgua, ambos acoplados a compressores de ar para aquÃrios. O experimento teve
duraÃÃo de 180 dias, sendo realizadas biometrias mensais, observando-se o
crescimento e o ganho em peso, bem como, o comportamento dos indivÃduos. A
alimentaÃÃo foi composta pelo molusco Tegula sp. e nÃuplios recÃm eclodidos de
Artemia franciscana na proporÃÃo de 2 nÃuplios/ml, ofertada uma vez ao dia atà a
saciedade dos juvenis. A temperatura da Ãgua foi mantida constante atravÃs de
aquecedores termostatos, e, os valores de pH e salinidade controlados sempre
que necessÃrio com trocas parciais de Ãgua. Ao final do experimento, obteve-se
os seguintes percentuais de sobrevivÃncia: 75%, 100%, 100% e 75% para os
tratamentos 24, 26, 28 e 30 ÂC, respectivamente, sendo que os indivÃduos
pertencentes ao tratamento 32 ÂC morreram antes de completar um mÃs de
cultivo. Os valores mÃdios de pH e salinidade para os tratamentos 24, 26, 28 e
30ÂC, foram: 7,86 Â 0,31; 7,56 Â 0,3; 7,91 Â 0,31; 7,67 Â 0,31 e 38,6 Â 1,3â; 38,6Â
1,1â; 38,8 Â 0,9â; 38,8 Â 1â, respectivamente, permanecendo dentro da faixa
de normalidade segundo o Teste de Kolmogorov-Smirnov e iguais
estatisticamente atravÃs do Teste t-Student (Â = 0,05). Os dados biomÃtricos
finais para os tratamentos 24, 26, 28 e 30 ÂC, foram: 5,104 g, 24,3 mm e 52,1 mm;
8,345 g, 29,8 mm e 63,6 mm; 9,129 g, 32,7 mm e 69,9 mm; 5,971 g, 23,2 mm e
52,8 mm para o peso, comprimento do cefalotÃrax e comprimento total,
respectivamente. Foi observado ainda, um total de 39 mudas no experimento,
sendo oito para o tratamento 24 ÂC, dez para o tratamento 26 ÂC, treze para o
tratamento 28 ÂC e oito para o tratamento 30 ÂC. Os procedimentos estatÃsticos mostraram que houve diferenÃa estatÃstica significativa entre os tratamentos ao
final do experimento, comprovado atravÃs da ANOVA e do Teste de Tukey (P <
0,05), sendo analisadas as mÃdias de peso e dos comprimentos, bem como, os
percentuais dos incrementos em crescimento e perÃodo de intermudas dos
indivÃduos. A taxa de sobrevivÃncia final nÃo apresentou diferenÃa estatÃstica
significativa atravÃs do Teste do Qui-Quadrado (P > 0,05). Analisando os dados
separadamente, podemos concluir que o tratamento 28 ÂC representou a melhor
temperatura em relaÃÃo ao desenvolvimento de juvenis recentes de P. argus em
ambiente controlado, quando comparado Ãs temperaturas 24, 26, 30 e 32 ÂC sob
as mesmas condiÃÃes. Existe um consenso por parte da comunidade cientÃfica e
de empresÃrios vinculados ao setor lagosteiro que sÃo necessÃrios mais estudos
sobre o cultivo de lagostas, cujo objetivo maior à implantar um projeto piloto
sustentÃvel no ambiente marinho, visando gerar emprego e renda para as
comunidades locais e tambÃm aumentar a oferta desse recurso no mercado, pois
sua pesca jà se encontra com fortes declÃnios de produÃÃo / Because of the great economic importance of the spiny lobster in North-east
Brazil, mainly in Ceara State and also most fisheries are overexploited,
Aquaculture Technology Center, Federal University of Ceara has been directed
research towards essential technical design for basic methodology to the culture of
spiny lobster in laboratory. Then, the objective of the present study is to verify the
influence of five differents temperature in development of early juvenile spiny
lobster Panulirus argus in laboratory. An entirely random delineation was applied:
24, 26, 28, 30 e 32 ÂC, resulting in 5 treatments, repeated 4 times, coming to a
total of 20 individuals, Recent offspring of P. argus lobster were captured with a
plastic fish trap in the low tides of spring tides (0.0 and â 0.1m) near English
bridge, Iracema Beach, Fortaleza, Ceara, Brazil. The initial average weight (g),
average cephalotorax (mm) and total (mm) length of spiny lobsters were 2.680g;
13.8mm e 40.4mm, respectively. The individuals development was determined
through the analyses and observations of the following parameters: increments in
weight and length, number of molts, intermolt periods and survival rate. Chemical
and physical parameters, biometric data, number and frequency of molts per
individual, survival rate were analyzed for the determination of statistical tests. The
experiment was conducted in 5 polyethylene box, measuring 37 x 55.5 cm, with
capacity each for 30 liters of water. The spiny lobster culture system was provided
with biological filter and artificial aeration to improve water quality. The experiment
was carried out during 180 days. Biometric data was recorded every month,
observing behavior, weight and length of individuals. Animals were fed on mollusk Tegula sp. and live Artemia nauplii consisting of 2 nauplius/ml. The juvenile were
fed once a day. Water temperature was maintained constant by a heater with
thermostat. When necessary, the value of pH and salinity was maintained
changing part of culture water. At the end of experiment, survival rate were 75%,
100%, 100% e 75% for the treatments 24, 26, 28 e 30 ÂC, respectively. The
individuals died within one month for the treatment 32 ÂC. The average value of pH
and salinity for the treatments 24, 26, 28 e 30 ÂC, were: 7.86 Â 0.31; 7.56 Â 0.3;
7.91 Â 0.31; 7.67 Â 0.31 e 38.6 Â 1.3â; 38.6Â 1.1â; 38.8 Â 0.9â; 38.8 Â 1â,
respectively, remaining within the normal level according to the Kolmogorov-
Smirnov test and statistically equal through t-Student test (Â = 0.05). The final
biometric data for the treatments 24, 26, 28 and 30 ÂC, were: 5.104 g, 24.3 mm
and 52.1 mm; 8.345 g, 29.8 mm and 63.6 mm; 9.129 g, 32.7 mm and 69.9 mm;
5.971 g, 23.2 mm and 52.8 mm for the weight, cephalotorax and total lengths. It
was observed yet in the experiment, a total of 39 molts, 8 for the treatment 24 ÂC,
10 for the treatment 26 ÂC, 13 for the treatment 28 ÂC and 8 for the treatment 30
ÂC. The statistical procedure ANOVA and Tukey Test (P < 0.05) at the end of
experiment showed that there were significant differences among the treatments
being analyzed average weight and length, increments percentage in growth and
intermolt period of the individuals. The final survival rate didnÂt showed statistical
significant differences with Qui-Quadrado test (P > 0.05). We can concluded that
the treatment 28 ÂC represented the best temperature in relation to the
development of early juveniles P. argus in controled environment, when the
temperature 24, 26, 30 e 32 ÂC were compared under the same condition. There is a consensus of opinion of the scientific communities and businessman linked to the
fishing enterprises which more research is needed on the culture of the spiny
lobster, whose main objective is to develop a pilot project economically feasible in
marine environment, contributing to the generation of profitable activity and
employment to the local communities and also increasing yields and delivered to
markets. Thus assuming that growth overfishing is bound to be the main cause of
decline in the catch of spiny lobster
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Mariculture as a means to add value to the east coast rock lobster Panulirus homarus rubellus subsistence fishery : a physiological approach to define transport and growout protocols for wild caught juvenilesKemp, J O G January 2009 (has links)
In a context of declining capture fisheries and public pressure for greater access to marine resources, marine aquaculture is receiving increasing interest from the South African government as a means to increase the diversity of economic activities in coastal regions, thereby providing employment and reducing poverty. The east coast rock lobster Panulirus homarus rubellus is currently harvested by subsistence fisherman along the former Transkei coastline of south-east South Africa and presents a possible opportunity for ongrowing wild juvenile lobsters in culture facilities. Lack of compliance coupled with poor enforcement of the minimum size limit (65 mm carapace length) has resulted in the ongoing harvest of undersize size lobsters by subsistence fishers. Generally, fishers either consume these undersize lobsters or sell them to tourists for low prices. In line with international trends in rock lobster aquaculture, interest has subsequently arisen in the possibilities of ongrowing these undersize lobsters as a means of adding value to the P. h rubellus resource for subsistence fishers. The aim of this physiological study was to assess the biological feasibility of harvesting, transporting and culturing wild caught juvenile lobsters, thereby provide empirical data to inform the development of suitable transport and culture protocols. The experimental objectives were to asses the effect of temperature on growth and survival of P. h. rubellus, as well as the effects of a suite of extrinsic and intrinsic factors on ammonia excretion and oxygen consumption. Juvenile lobsters were collected by hand from near-shore reefs (2-15 m depth) off Mdumbi in the former Transkei, Eastern Cape Province and transported by road (7 hours) to the Port Alfred Marine Research Laboratory where they were held in a recirculating culture system. The effect of temperature over a range of 9.7 °C (18.9±0.7 to 28.6±1.5 °C) on the growth and survival of juvenile P. h. rubellus fed a diet of fresh mussel flesh was investigated. Specific growth rate (SGR) was significantly different between temperatures (p = 0.01), with the highest values recorded for the 24 °C and 28 °C treatments. There was no significant difference in moult increment (MI) between temperatures, however, intermoult period (IMP) differed significantly between temperatures (p = 0.0015) with mean IMP lowest at 24 °C, although not significantly different from the means of the 26 °C and 28 °C treatments. IMP was highest at 19 °C and 21 °C. Apparent feed intake was significantly different between treatments (p < 0.0001) and exhibited a strong positive correlation with increasing temperature. Food conversion ratio (FCR) differed significantly between temperatures (p = 0.02) with 24 °C exhibiting the most efficient FCR. The results for growth rate and food conversion efficiency suggested that 24 °C is optimal for the growout of juvenile P. h. rubellus. In the second study, the effect of body weight, emersion, daily rhythm, feeding and ambient ammonia on the total ammonia nitrogen (TAN) excretion rate was investigated. Body weight (n = 16, range of 16.8 – 322 g) was positively correlated to daytime TAN excretion rate (mg h⁻¹). Re-immersion after one hour emersion in a moist environment was characterized by a significant increase in TAN excretion rate for the first hour compared to pre-immersion levels. The amount of TAN excreted during this period was as expected if basal TAN excretion rates were maintained during emersion. TAN excretion rates returned to pre-emersion levels by the end of the second hour. There was no evidence of a daily rhythm in TAN excretion rate for P. h. rubellus. TAN excretion rates were elevated following feeding. An initial peak in TAN excretion rate after seven hours (7.58 times pre-feeding rate) was followed by a smaller peak after 13 hours (6.69 times pre-feeding rate). TAN excretion rate dropped to levels not significantly different from pre-feeding levels after 23 hours and consistently returned to pre-feeding levels after 42 hours. The TAN excretion rates of lobster exposed for two hours to an ambient TAN concentration of 1.02±0.10 mg l⁻¹ and 2.3± 0.2 mg l⁻¹ were not significantly different from TAN excretion rates recorded at low ambient water TAN prior to exposure. Exposure to an ambient TAN concentration of 4.45±0.78 mg l⁻¹ had a significant effect on the TAN excretion rate, with pronounced ammonia uptake occurring for all animals at this concentration. The third study investigated the effects of body weight, diurnal rhythm, feeding and emersion on lobster oxygen consumption. Body weight was positively correlated to both standard and active oxygen consumption (mg O2 h⁻¹) while body weight was negatively correlated to mass-specific standard oxygen uptake (mg O2 g⁻¹ h⁻¹). Diurnal rhythm exhibited a strong effect on the lobsters oxygen consumption, with average night time values 67% greater than those recorded during the day. This was related to activity driven by intrinsic nocturnal foraging behaviour. Feeding resulted in a classic specific dynamic action (SDA) response, with postprandial oxygen consumption increasing to a peak before decreasing gradually to preprandial levels. Emersion resulted in a significant increase in oxygen consumption, with lobsters rapidly recovering to pre-emersion levels after four hours. Results from these studies suggest that the capture, transport and culture of juvenile P. h. rubellus is biologically feasible. Empirical data generated were used to provide recommendations regarding species optimised transport and culture protocols. A purge time of 48 hours before transport is suggested to ensure that ammonia excretion and oxygen consumption are at basal levels. Furthermore, emersed transport for a period of one hour is characterised by rapid recovery upon re-immersion. In order to prevent the accumulation of stressors, it is suggested that consecutive periods of emersion are interjected with recovery periods (five hours) in water to allow the removal of accumulated ammonia and repayment of the oxygen debt incurred. The recorded ammonia rates indicate that a biological filter size of 4.8 m³ is recommended for 1000 kg of fed lobsters in a culture situation, although this can be reduced considerably if lobsters are being held without feeding (0.72 m³). A flow rate of 112 l kg⁻¹ h⁻¹ is required to meet the metabolic requirements of lobsters. Bottlenecks to the viable commercial culture of P. h. rubellus, and the ability of this practice to provide the socio-economic benefits that were envisioned, are discussed.
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Towards the development of a protocol for rearing juvenile rock lobster, Jasus lalandiiEsterhuizen, J. A January 2005 (has links)
The diversification of current aquaculture practise in South Africa is crucial for the future development of the industry. The rock lobster, Jasus lalandii has been identified as a possible candidate species for shore based culture in systems similar to those used for abalone farming. Reduced Total Allowable Catch (TAC's) and an increased minimum legal size were implemented as management strategies to relieve fishing pressure on natural stocks of J. lalandii, and in turn led to increased market demand and a possible niche for farmed lobsters. High puerulus settlement along the Namibian coast, together with other favourable aquaculture attributes, indicate that the commercial grow out of wild harvested juveniles could be feasible. The aim of study was to investigate the feasibility of growing out rock lobsters in shore based systems in Namibia and South Africa. The experimental objectives of the project were to investigate the nutritional requirements, as well as the effect of stocking density and tank design on growth and survival of J. lalandii. The economic viability of shore based rock lobster farming was then evaluated based on the experimental results and typical capital requirements of an abalone farm in South Africa. Puerulus and early juvenile rock lobsters were collected in Luderitz, Namibia and transported to HIK Abalone Farm in Hermanus, South Africa where they were acclimated in black fibre glass tanks in a flow through system. The pueruli were stocked at 50, 75, 100 and 125/m² and early juveniles at 20, 30, 40 and 50/m² to test the effect of density on growth and survival. A comparative dietary study with both size classes was conducted using a mussel diet (Choromytilus meridionalis and Mytilus galloprovincialis), a commercial shrimp feed diet and a rotational diet comprising both mussels and shrimp feed. Tanks provided with "v-shaped" asbestos hides, PVC hides and no hides were compared to test the effect on growth rate and survival of pueruli. All treatments were conducted in triplicate. Temperatures were recorded twice daily while water quality parameters were tested every second week. The results indicate that density had a significant effect on growth and survival on post-pueruli. An initial stocking density of 75 post-pueruli/m² is regarded as optimal both in terms of the growth rate and biomass production per tank. No differences in growth and survival rates were attained in the early juvenile size class. This indicates that higher densities can be used to rear juvenile J. lalandii. No significant differences were obtained in growth rate when reared under different hide conditions although asbestos hides yielded significantly higher survival rates (93.3 %) compared to the tanks provided with PVC hides (74.04 %) and no hides (77.8 %, p≤0.05). As a result of the high survival rate observed in tanks provided with "V-shaped" asbestos hides, these tanks also yielded higher biomass production per tank (297.8 grams) compared to the tanks provided with PVC hides and no hides (261.09 and 260.5 grams respectively). In the diet trials, growth rates of post pueruli and juvenile lobsters fed the mussel and rotational (mussel and shrimp feed) diets did not differ significantly, however, growth rates of lobsters fed the shrimp feed only diet was significantly lower than both the mussel and rotational diets (p≤0.05). Lobsters fed the mussel diet yielded significantly higher survival rates compared to lobsters fed either the rotational diet or shrimp feed diet only. An imbalance in the fatty acid profile of the shrimp feed could have been a major contributing factor to the poor growth and survival in lobsters fed the shrimp feed only diet as the level of linoleic acid (LOA) was exceptionally high resulting in a high (n -6):(n-3) ratio (1.01) compared to the mussel and rotational diets (0.17 and 0.56 respectively). The low level of arachidonic acid (ARA) in the shrimp feed diet could be a further contributing factor explaning for the poor growth and survival of juvenile rock lobsters. An economic feasibility study was conducted at the end of the experimental phase by modelling a hypothetical shore based rock lobster farm. A projection of production costs and revenues was based on the typical costs of a shore based abalone farm and the current market prices for wild harvested J. lalandii. The economic viability was evaluated using benefit-cost ratios, payback period, internal rate of return and breakeven analysis. Sensitivity analyses revealed that the projected lobster growth and survival rates were the main biological factors influencing the economic feasibility of the hypothetical rock lobster farm. An assumed four year grow out period at a low stocking density yielded more lucrative internal rate of return (IRR), benefit-cost ratio, payback period and net present values (NPV) than a five year grow out period at a high density. The four year grow out scenario proved to be more robust to the fluctuating Rand/US$ exchange rate and could accommodate a lower lobster survival rate. Results presented in this study indicate that rock lobster farming is a marginal commercial prospect based on current production performance and costs. Further research to develop effective puerulus collection techniques as well as to make lobster grow out technology more cost effective is required.
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Diet and trophic role of western rock lobsters (Panulirus cygnus George) in temperate Western Australian deep-coastal ecosystems (35-60m)Waddington, Kris Ian January 2008 (has links)
[Truncated abstract] Removal of consumers through fishing has been shown to influence ecosystem structure and function by changing the biomass and composition of organisms occupying lower trophic levels. The western rock lobster (Panurilus cygnus), an abundant consumer along the temperate west coast of Australia, forms the basis of Australia's largest single species fishery, with catches frequently exceeding 11000 tonnes annually. Despite their high abundance and commercial importance, the diet and trophic role of adult lobster populations in deep-coastal-ecosystems (35-60 m) remains unknown. An understanding of the diet and trophic role of lobsters in these ecosystems is a key component of the assessment of ecosystem effects of the western rock lobster fishery. This study uses gut content and stable isotope analyses to determine the diet and trophic role of lobsters in deep-coastal ecosystems. Dietary analysis indicated adult lobsters in deep-coastal ecosystems were primarily carnivorous with diet reflecting food available on the benthos. Gut content analyses indicate crabs (62 %) and amphipods/isopods (~10 %) are the most important lobster dietary sources. Stable isotope analysis indicates natural diet of lobsters in deep coastal ecosystems is dominated by amphipods/isopods (contributing up to ~50 %) and crabs (to ~75 %), with bivalves/gastropods, red algae and sponges of lesser importance (<10 % of diet each). Diet of lobsters in deep-coastal ecosystems differed from that reported for lobsters inhabiting shallow water ecosystems in this region, reflecting differences in food availability and food choice between these ecosystems. Bait from the fishery was also determined (by stable isotope analyses) to be a significant dietary component of lobsters in deep-coastal ecosystems, contributing between 10 and 80 % of lobster food requirements at some study locations. '...' Given observed effects of organic matter addition in trawl fisheries, and also associated with aquaculture, bait addition is likely to have implications for processes occurring within deep-coastal ecosystems in this region, particularly given its oligotrophic status, most likely by increasing the food available to scavenging species. Removal of lobsters from deep-coastal ecosystems may affect the composition and abundance of lobster prey communities through a reduction in predation pressure. Such effects have been demonstrated for other spiny lobster species. These effects are typically most observable amongst common prey taxa which in other studies have been commonly herbivores. In deep-coastal ecosystems, crabs and amphipods/isopods are the most common prey taxa and most likely to be effected. The ecosystem-impacts of top-down control of non-herbivorous prey species is unknown and constrains the inferences possible from this study. However, the establishment of 'no-take' areas in deep-coastal ecosystems would allow the ecosystem effects of lobster removal to be further assessed in these deep-coastal ecosystems. While data from the current study did not allow the ecosystem effects of lobster removal to be properly assessed, this study provided information regarding the ecology of western rock lobsters in previously unstudied ecosystems.
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Engorda de juvenis recentes da lagosta espinhosa panulirus laevicauda (latreille, 1817) alimentados com ração comercial para camarão marinho e os moluscos mytella falcata e perna perna, em condições de laboratório / Fattening of juvenile spiny lobster recent panulirus laevicauda (Latreille, 1817) fed a commercial diet for shrimp and clams Mytella falcata and leg leg in laboratorySantos, Carlos Henrique dos Anjos dos January 2006 (has links)
SANTOS, Carlos Henrique dos Anjos dos. Engorda de juvenis recentes da lagosta espinhosa panulirus laevicauda (latreille, 1817) alimentados com ração comercial para camarão marinho e os moluscos mytella falcata e perna perna, em condições de laboratório. 2006. 92 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrária, Departamento de Engenharia de Pesca, Fortaleza-CE, 2006 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-12T12:05:16Z
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Previous issue date: 2006 / The spiny lobster represents an important economic fisheries resource in Ceara State, contributing to the generation of profitable activity and employment. Due to the exploitative and destructive fishing practices, along with the degradation of the natural habitat from pollution and human activity, a precipitous decline in the wild populations has occurred. This activity had begun by 1950s. Since then, different types of vessel and gears were used to catches of this resource. However, with the catches of this crustacean and the growing market demand, as a consequence, decrease natural stock. At present, this activity have had a strong decrease and one of the few ways to expand production is through aquaculture or culture of these species in captivity. In view of this decline, the objective of the present study is to analyze the development of early juvenile spiny lobster Panulirus laevicauda fed on molluscs Perna perna, Mytella falcata and commercial marine shrimp ration + Artemia sp. biomass, in laboratory condition. This experiment was carried out in the Aquaculture Technology Center, Federal University of Ceara in a 122 days feeding trial. The juveniles were submitted to three treatment (treatment A – P. perna, treatment B – M. falcata and treatment C – commercial ration + Artemia sp. biomass) repeated 4 times. Initial density used was one individual per container. The feed rate was 10 % of the individual biomass. During the experiment bromatological analyses of the feed was done, verifying protein, lipids, ash, carbohydrate and humidity. The chemical and physical parameters of the experimental water (pH, temperature and salinity), were measured daily and the juveniles were measured verifying cephalotorax and total length and weighed at each 30 days of culture. At the end of the experiment, chemical and physical parameters, biometric data, number and frequency of molts per individual, survival rate were analyzed for the determination of statistical tests. Analysis with Kolmogorov-Smirnov the Student Test (chemical and physical parameters), Analysis of Variance (ANOVA) and if necessary the Tukey Test (biometric data, number and frequency of molts and intermoult per individual) and test Qui-Quadrado of Pearson (survival rate), respectively. For the statistical tests, it has been used µ = 0,05 significance level. In this work chemical and physical parameters showed minimum, maximum and medium value much close among the treatments. Analysis with Kolmogorov-Smirnov showed that pH, temperature and salinity, attended normal supposition. These parameters showed no significant differences (P > 0,05) with the Student Test during the cultures among the treatments. After finished the experiment, chemical and physical parameters, biometric data, number and frequency of molts per individual, survival rate were analyzed for the determination of statistical tests. The results of gross weight (g) and cephalotorax (mm) and total (mm) length of spiny lobsters of treatment C showed a slight development compared to spiny lobsters of treatments A and B (P > 0,05). On the other hand, increment of cephalotorax (mm) and total (mm) length, showed alternation among the treatments. The value of these increments were slight lower for the treatment C (P > 0,05), respectively. The results of increments in treatment B showed slight better in relation to the treatment A and C(P > 0,05) respectively. The bromatological analyze of food in treatment B showed higher protein, lipid and carbohydrate value and the diet of treatment C showed lower value, respectively. The spiny lobster of treatment A, B, and C showed almost the same number of moults and intermoult periods (P > 0,05). The survival rate was also closed each other, and in some treatments almost the same (P > 0,05). We concluded that early juvenile spiny lobster P. laevicauda can be fed on diets used in this experiment. In addition the individuals accepted commercially formulated shrimp feeds. This fact contribute to the development of the methodology on the culture of lobsters, with speculation on the possible adaptations that can be useful to the final development of commercially incomeproducing units. / A lagosta é um recurso pesqueiro de grande importância econômica para o Estado do Ceará. Esta atividade teve seu início na década de 50 e de lá para cá, vários tipo de embarcações e artes-de-pesca foram utilizadas para a captura deste recurso. No entanto, com o início da exploração deste crustáceo, veio consequentemente a diminuição dos estoques naturais, e isto, devido a grande demanda do setor pelo produto, que forçou dessa maneira a exploração deste recurso. Atualmente, esta atividade esta em forte declínio e uma das formas para reverter esse quadro seria através da aqüicultura, ou seja, do cultivo de nossas espécies em cativeiro. O presente trabalho teve como objetivo de avaliar o desenvolvimento de juvenis recentes da lagosta espinhosa Panulirus laevicauda, alimentadas com os moluscos Perna perna, Mytella falcata e ração comercial para camarão marinho + biomassa de Artemia sp., em condições de laboratório. Este experimento foi realizado nas instalações do Centro de Tecnologia em Aquicultura da Universidade Federal do Ceará, em um período de 122 dias. Este trabalho foi dividido em três tratamentos (tratamento A – P. perna, tratamento B – M. falcata e tratamento C – ração comercial + biomassa de Artemia sp.) com quatro repetições cada. A taxa de densidade inicial utilizada foi de um indivíduo por repetição. Os alimentos foram ofertados de acordo com 10% da biomassa dos indivíduos. Durante o experimento foram realizadas as análises bromatológicas dos alimentos, sendo verificados as quantidades de proteínas, lipídeos, cinzas, carboidratos e umidades. Os parâmetros físico-químicos (pH, temperatura e salinidade) foram observados diariamente e as biometrias (peso, comprimento do cefalotórax e total) mensalmente. Diariamente, se observava a ocorrência de mudas nos tratamentos com os seus respectivos dias. Após o término do experimento os parâmetros físico-químicos, os dados biometricos, os números de mudas, as freqüências de mudas e as taxas de sobrevivência foram analisadas por testes estatísticos. Os testes estatísticos utilizados foram o Kolmogorov-Smirnov e o teste “t” de Student (parâmetros físico-químicos), a Análise de Variância (ANOVA) e se necessário o teste de Tukey (biometrias, número de mudas, período de intermudas) e o teste do Qui-quadrado de Pearson (sobrevivência), respectivamente. Os níveis de significância utilizado nos testes estatísticos foram de µ = 0,05. Os parâmetros físico-químicos deste trabalho mostraram valores mínimos, máximos e médios muito próximos entre si. Com a realização do teste de Kolmorogov-Smirnov, o mesmo mostrou que o pH, temperatura e salinidade, atenderam a suposição de normalidade. Ao comparar estes parâmetros com o teste “t” de Student, foi verificado que não houve diferença estatística significativa entre os tratamentos (P > 0,05). Ao analisamos os resultados do crescimento em peso (g), ganho de peso (g), crescimento do comprimento do cefalotórax (mm) e do comprimento total (mm) em valores brutos, observamos que as lagostas do tratamento C apresentaram um ligeiro desenvolvimento em comparação aos tratamentos A e B (P > 0,05). Por outro lado, os ganhos de comprimento do cefalotórax (mm) e do ganho de comprimento total (mm), apresentaram alternância entre os tratamentos, sendo que os valores destes ganhos foram um pouco menor para o tratamento C (P > 0,05). Todos os incrementos aqui analisados seguiram as seguintes seqüências, o tratamento B apresentou-se um pouco melhor em relação aos tratamentos A e C (P > 0,05). As análises bromatológicas da dieta do tratamento B apresentaram valores de proteína, lipídeos e carboidratos mais altos em relação ao tratamento C que apresentou os valores menores entre as dietas, respectivamente. As lagostas do tratamento A, B e C, apresentaram praticamente o mesmo número de mudas e o período de intermudas (P > 0,05). A taxa de sobrevivência foi também bastante próxima uma da outra, chegando em alguns tratamentos serem praticamente iguais (P > 0,05). Concluirmos que os alimentos utilizados neste experimento podem ser utilizados na alimentação de juvenis recentes da lagosta espinhosa P. laevicauda. Outro resultado animador obtido neste trabalho foi à aceitação pela lagosta da dieta artificial, já que uma das grandes problemáticas em um projeto piloto de cultivo de nossas espécies, seriam a aceitação das mesmas por uma dieta peletizada.
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