Browsing by Author "Palma, Jorge"
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- Behavioral traits of captive short-snouted seahorse Hippocampus hippocampus, Linnaeus 1758Publication . Gristina, Michele; Pierri, Cataldo; Lazic, Tamara; Palma, JorgeStudies of behavioral traits of threatened marine species are fundamental in order to plan correct conservation strategies. This information becomes crucial to seahorses conservation, given the poor swimming skills and small home ranges of these fishes. Although information with regards to seahorse behaviors has increased in the last period, there is still a severe lack of knowledge concerning behavioral traits of the majority of Hippocampus spp. worldwide. The present study aims to present preliminary data on behaviour traits of captive H. hippocampus (short-snouted seahorse) under different conditions of habitat complexity and water temperature. In agreement with previous studies conducted on congeneric species H. hippocampus showed great thermal tolerance at least in the thermal range used in the present experiment. On the contrary, significant differences were found in behaviors adopted in the presence and absence of the algal component. However, it will be necessary to further investigate H. hippocampus behavior also in consideration of its interactions with the congeneric H. guttulatus when they occur sympatrically.
- A crown for each monarch: a distinguishable pattern using photo-identificationPublication . Correia, Miguel; Antunes, Daniela; Andrade, José Pedro; Palma, JorgePhoto-identification has been proven to be a successful individual recognition tool in seahorse species (e.g., long-snout seahorse Hippocampus reidi (Ginsburg, 1933) and long-snouted seahorse Hippocampus guttulatus (Cuvier, 1829)). Its use was deemed valuable for the assessment of wild populations and to understand variations in abundance over time when capture-recapture methods are needed. In this study, a computer software with a pattern recognition algorithm (I3S® Contour 3.0) was used for individual identification of short-snouted seahorses Hippocampus hippocampus (Linnaeus 1758) in the laboratory. Using this methodology, differences in the shape of each individual’s coronet were tested as a unique and distinguishable characteristic. Two different contours were used as reference and tested to assess the effectiveness of this method in individual identification. A total of 94 captive-bred H. hippocampus, 45 adults (> 1 year old) and 49 young adults (4 months old), were tested. Positive matches were obtained in 55.1 % of the young adults and 84.4 % of the adults using contour 1; and in 77.6 % and 97.8 % for young adults and adults, respectively, using contour 2. All un-matched photos were later successfully matched by visual comparison, using additional traits (e.g., spot patterns) and gender. This methodology yielded very promising results and could be further used in wild individuals to allow population size estimates.
- Different behavioral strategies of two sympatric seahorses: habitat availability and increased density of Hippocampus guttulatus alter the behavior of Hippocampus hippocampusPublication . Spatafora, Davide; Gristina, Michele; Quattrocchi, Federico; Pierri, Cataldo; Lazic, Tamara; Palma, JorgeIn the light of future ocean warming scenarios and habitat fragmentation, coastal fishes must adjust their physiological and behavioral traits to face the combined effect of global warming and ecological interactions. Seahorses (Hippocampus spp.) are charismatic fishes with peculiar life cycle traits, which make them vulnerable to several anthropic pressures and natural disturbances. In this study, we investigated the behavior of two sympatric seahorse species, the long-snouted Hippocampus guttulatus (Cuvier, 1829) and the short-snouted Hippocampus hippocampus (Linnaeus, 1758). Specifically, we carried out two manipulative experiments to assess (i) the effect of temperature and habitat availability on both H. hippocampus and H. guttulatus behavior and (ii) the effect of temperature and an increased density of H. guttulatus (by 3x) on the activity level of congeneric species H. hippocampus. Our results showed that +3 & DEG;C warming did not affect seahorse behavior in both experiments, suggesting greater behavioral tolerance to thermal variation. However, a significant reduction of the active behavior of H. hippocampus was observed when the artificial habitat was introduced in the tank, while H. guttulatus maintained its activity. Furthermore, a significant decrease of the H. hippocampus activity was observed with an increased relative dominance of H. guttulatus. Our results suggest that both increased density of H. guttulatus and habitat availability, but not ocean warming, will affect the behavior of H. hippocampus. Therefore, different interspecific behavioral strategies may occur, thus affecting the distribution of the two species among shallow habitats when they occur in sympatry.
- Editorial: Syngnathid fishes: biology, ecology, physiology, conservation and innovative rearing techniquesPublication . Planas, Miquel; Gristina, Michele; Palma, Jorge; Qin, Geng; Rose, Emily; Roth, Olivia; Teske, Peter R.Syngnathids (a bony fish family that includes seahorses, pipefishes and seadragons) have unique morphological and biological traits that include fused jaws, an exoskeleton and male parental care (Ahnesjö and Craig, 2011). They are mostly found in shallow coastal areas, and their unconventional life history renders them particularly vulnerable to population depletion (Foster and Vincent, 2004). Although some species have been listed as Vulnerable, Endangered, and even Critically Endangered by the IUCN Red List of Threatened Species, many are classified as Data Deficient (DD) due to insufficient information (IUCN, 2020; Pollom et al., 2021). Therefore, further research is needed to understand their distribution, population trends and main threats. A significant portion of the research on syngnathids is relatively recent (Cohen et al., 2017; Segaran et al., 2023). This Research Topic provides 12 original research and review contributions that provide an overview of current trends in research related to the biology, physiology, ecology and conservation of syngnathids. We have gained considerable insights into syngnathid evolutionary innovation, particularly concerning the evolution of male pregnancy (Lin et al., 2016; Roth et al., 2020). The review by Parker et al. sheds light on the unique modification of the syngnathid immune system and its associations with physiology and reproduction, and highlights future research objectives.
- Effects of anthropogenic noise as a source of acoustic stress in wild populations of Hippocampus guttulatus in the Ria Formosa, south PortugalPublication . Palma, Jorge; Magalhães, Marisa Gonçalves; Correia, Miguel; Andrade, José PedroThis study evaluated the effects of underwater noise as a source of acoustic stress in the wild populations of Hippocampus guttulatus in the Ria Formosa, south Portugal. Two different scenarios of underwater noise were tested: transient motor boat sound (63.4-127.6 dB) and constant sound produced by the motor of the boat directly above the animals (up to 137.1 dB). Observations were obtained in the wild between 4 and 10 m depth throughout a 3 min period, using a video camera and a hydrophone set, and compared with a control sample. A significant increase (P < 0.05) in the respiratory rate was observed in 87% of the observed fish. Opercular movements per minute (OMPM) increased from 35.7 +/- 10 (control sample) to 41.2 +/- 15.5 after the first minute, to 45.5 +/- 13.3 after the second (both under transient sound) and to 49.7 +/- 12.5 after the third (under constant sound exposure). Differences in means between the control fish and fish observed during the second (P < 0.01) and third minute of observation (P < 0.0001) were significant. Concordantly, a significant increase (P < 0.05) in the OMPM of fish observed in the first minute and the third minute was noted. In addition to the OMPM increase, 37.5% of the animals abandoned the observation location presumably in an attempt to avoid the negative sound stimuli. The noise caused by boat traffic generated an immediate physiological response, expressed as an increase in OMPM, and a behavioural response resulting in site abandonment, which together can be considered as a negative impact on the seahorse populations. This work contributes to an increasing number of studies that have shown that boat traffic can induce ecological and environmental consequences to aquatic species. Future research should evaluate how navigation exclusion areas could have a positive impact on the seahorse populations inhabiting shallow coastal areas.
- Extensive gene loss parallels kidney aglomerulism in SyngnathidaePublication . Pinto, Bernardo; Machado, André M.; Cordeiro, J. Miguel; Kolbadinezhad, Salman Malakpour; Fonseca, Elza; Andrade, Jose; Palma, Jorge; Ruivo, Raquel; Monteiro, Nuno; Wilson, Jonathan M.; Castro, L. Filipe C.The eccentric seahorses, seadragons, pipehorses and pipefishes (Syngnathidae) have an aglomerular kidney1. Here, we show that nephron genes2 conserved in Bilateria are secondarily eroded/deleted in Syngnathidae genomes. A transcriptome enrichment analysis suggests the predominance of excretion processes in the Syngnathidae kidney. In a lineage where crypsis and idleness are tightly associated, we propose that aglomerulism evolved as an energy-saving strategy.
- Fatty acid profiles of cultured hippocampus hippocampus trunk muscles and potential nutritional valuePublication . Cabral, Ana Elisa; Rey, Felisa; Domingues, M. Rosário; Cabral, Miguel; Planas, Miquel; Palma, Jorge; Calado, RicardoSyngnathids (seahorses, pipefishes and seadragons) are an attractive resource for Traditional Chinese Medicine (TCM). Despite few scientific studies supporting seahorse nutritional benefits, they are believed to possess medicinal properties that enhance human health. The European short-snout seahorse Hippocampus hippocampus is classified as Data Deficient by the IUCN Red List of Threatened Species. Nevertheless, there are increasing records of this species being illegally captured and traded to supply TCM. This study investigated the fatty acid (FA) profiles of the trunk muscles of cultured female and male H. hippocampus, to assess sex and intraspecific variation, as well as their potential nutritional value. The contents of crude lipid (4.05 +/- 2.15% dry weight, DW in females and 2.82 +/- 1.48% DW in males) and phospholipid (8.23 +/- 3.34 mu g mg(-1) DW in females and 7.91 +/- 2.36 mu g mg(-1) DW in males) were not significantly different between the two sexes. The absolute FA compositions of H. hippocampus trunk muscles revealed higher mean values for FA 16:0, 18:0, 18:1 n-9 and 22:6 n-3 (DHA), in both female (2.82 +/- 1.11, 1.81 +/- 0.89, 0.90 +/- 0.41 and 0.93 +/- 0.35 mu g mg(-1) DW, respectively) and male specimens (1.99 +/- 0.95, 1.52 +/- 0.78, 0.74 +/- 0.44 and 0.80 +/- 0.41 mu g mg(-1) DW, respectively). In terms of FA classes, saturated fatty acids (SFA) showed the highest absolute value of the total pool of FA, for both sexes (4.73 +/- 1.94 mu g mg(-1) DW in females and 3.58 +/- 1.76 mu g mg(-1) DW in males). Males tended to exhibit a more suitable profile for human nutrition, displaying a lower atherogenic index (AI) and thrombogenic index (TI). The relative composition of H. hippocampus trunk muscles followed the patterns of seahorse species valued in TCM, with DHA ranking amongst the PUFA with higher mean relative abundances (12.0% of total FA). While seahorse FA profiles may be of interest in terms of their nutritional value for humans, only specimens originating from sustainable production practices should be traded and the conservation of their populations in the wild should continue to be a global priority.
- Gastric evacuation and feeding in the gilthead sea bream reared under semi-intensive conditionsPublication . Andrade, José Pedro; Erzini, Karim; Palma, JorgeGastric evacuation rates of the gilthead sea bream, Sparus aurata, fed with commercial pelleted food and polychaetes (Nereis diversicolor) were determined under experimental conditions. The estimated gastric evacuation rate for pelleted food was 7.97% h(-1), with a total time of digestion of approximately 9 h. The respective values for the natural food were 6.24% h(-1), with a total digestion time of approximately 12 h. The daily consumption of fish reared in earth ponds in a semi-intensive aquaculture facility was estimated through 24h cycles performed between April and August. The daily consumption varied from 18.58 to 31.98 mg g(-1). There was a constant increase in the average daily consumption per individual of 1.8-4.6 g (dry weight). During these cycles, samples of stomachs were taken and the contents preserved for further observation. The feeding behaviour of the reared fish was compared with a fish sample caught in the Ria Formosa lagoon. No common species were found between samples. A total of 38 prey were identified, which suggests that the gilthead sea bream is a non-specific predator. Despite the high abundance of natural prey in the ponds, the dependence of sea bream on pelleted food was high.
- Growth performance of the early life stages of broad-nosed pipefish, Syngnathus typhle (L.) fed different live or frozen dietsPublication . Correia, Miguel; Palma, Jorge; Andrade, José PedroThis work tested the effect of using different live and frozen feed on the growth performance of Syngnathus typhle. It was divided into two experiments. In Experiment I Artemia and Atlantic ditch shrimp (Palaemonetes varians) larvae were used as live diets, whilst in Experiment II frozen mysids Mesopodopsis slabberi and frozen P. varians were used. At the end of the first experiment juvenile pipefish grew significantly more when fed P. varians (P < 0.05) with an overall Weight Gain (WG) of 914.8 +/- 79.3% bw day(-1), compared to Artemia fed fish (WG = 683.2 +/- 14.7%). Both mean Specific Growth Rate (SGR) and survival were similar between dietary treatments and did not vary significantly (P > 0.05). In Experiment II juveniles were weaned with frozen diets but no significant differences were found between the two tested diets in all parameters tested. Final WG was 516.5 +/- 63.3% and 566 +/- 17.6%, and Feed Conversion Ratio (FCR) was 30 +/- 1.5% and 28.2 +/- 1.2% for animals fed P. varians and M. slabberi respectively. Results indicate that P. varians is an adequate diet to use during initial stages of the S. typhle life cycle and should be considered as a frozen diet for subsequent life stages of this species as an alternative to currently known natural diets.
- Impacts of pineapple peel powder on growth performance, innate immunity, disease resistance, and relative immune gene expression of Nile tilapia, Oreochromis niloticusPublication . Palma, JorgeAn 8-week growth trial was conducted to examine the efficacy of pineapple peel powder (PAPP) on growth rate and immunity of Nile tilapia, O. niloticus. Three hundred Nile tilapia (20.91 ± 0.11 g) were fed five diets containing different levels of PAPP at 0, 10, 20, 30 and 40 g kg− 1 PAPP, respectively. After four and eight weeks of the feeding trial, growth rates, and immune responses were tested. A challenge test using Streptococcus agalactiae and relative immune gene expression were performed after eight weeks of PAPP feeding. It was found that skin mucus and serum lysozyme, skin mucus and serum peroxidase, alternative complement, phagocytosis, and respiratory burst activities were significantly increased with the addition of PAPP. The maximum (P ≤ 0.05) innate immune values were noted in fish fed 10 g kg− 1 PAPP. Similarly, the up-regulation of IL1, IL8, and LBP gene expressions were also detected in fish fed PAPP diets, with the maximum value was found in 10 g kg− 1 PAPP fed fish. The relative percentage of survival (RPS) of Oreochromis niloticus after the challenge test were (56.00%, 72.00%, 60.00%, and 44.00%) for the 5, 10, 20 and 40 g kg− 1 PAPP diets, respectively. Fish fed the 10 g kg− 1 PAPP supplemented diet achieved the highest (P < 0.05) survival rate against S. agalactiae. Growth and feed efficiency were outstandingly (P < 0.05) enhanced in the PAPP groups. In conclusion, PAPP can be potentially used as a feed additive in Nile tilapia culture under Biofloc system.