Evaluation of Long Sea Snail Hinia reticulata (Gastropod) from the Middle Adriatic Sea as a Possible Alternative for Human Consumption

Feeding snails (Archachatina marginata) with leaves: growth performance, carcass characteristics, nutrient digestibility, proximate composition and minerals contents of snail meat

This study explored the dietary impacts of some plant leaves (Centrosema pubescence leaves, Moringa oleifera leaves and Ipomea batata leaves) on the growth performance and carcass characteristics of Archachatina marginata reared in confinement. A twelve (12) weeks feeding trial on nine hundred and sixty (960) African giant land snails (A. marginata) fed various leaves was evaluated. The snails were allotted randomly on their experimental diets. The experimental diets were kitchen waste (leftover food) designated as the control (T1), C. pubescence leaves (T2), M. oleifera leaves (T3), and I. batata leaves (T4). Each treatment had two hundred and forty snails and was replicated four times with sixty snails each per replicate. The proximate compositions of these leaves were analyzed and showed significant values on the moisture content, crude protein, ether extracts, crude fiber, ash, and Nitrogen free extracts respectively. Data were collected on the performance, carcass characteristics, nutrient digestibility, proximate composition and minerals contents of snail meat. The results on the final weight, weight gain, average weight gain and FCR of snails showed that T4 (121.46, 36.10, 0.52 g and 1.49) were significantly (p < 0.05) different across treatment groups. Results on carcass characteristics showed that T4 had superior live weight, dressed weight, foot and dressing percentage values compared to the other groups. Also, T4 revealed significantly (p < 0.05) different across the diets on nutrient digestibility, proximate compositions of snail meat and the mineral composition of the snail meat compared to the other treatments. The study concluded that T4 (I. batata leaves) significantly influences the performance, carcass characteristic and mineral compositions of the snail meat and should be recommended as snail diet for optimum performance at an affordable cost.

A Metabolomic Analysis to Assess the Responses of the Male Gonads of Mytilus galloprovincialis after Heavy Metal Exposure

In recent years, metabolomics has become a valuable new resource in environmental monitoring programs based on the use of bio-indicators such as Mytilus galloprovincialis. The reproductive system is extremely susceptible to the effects of environmental pollutants, and in a previous paper, we showed metabolomic alterations in mussel spermatozoa exposed to metal chlorides of copper, nickel, and cadmium, and the mixture with these metals. In order to obtain a better overview, in the present work, we evaluated the metabolic changes in the male gonad under the same experimental conditions used in the previous work, using a metabolomic approach based on GC-MS analysis. A total of 248 endogenous metabolites were identified in the male gonads of mussels. Statistical analyses of the data, including partial least squares discriminant analysis, enabled the identification of key metabolites through the use of variable importance in projection scores. Furthermore, a metabolite enrichment analysis revealed complex and significant interactions within different metabolic pathways and between different metabolites. Particularly significant were the results on pyruvate metabolism, glycolysis, and gluconeogenesis, and glyoxylate and dicarboxylate metabolism, which highlighted the complex and interconnected nature of these biochemical processes in mussel gonads. Overall, these results add new information to the understanding of how certain pollutants may affect specific physiological functions of mussel gonads.

Meridionalization as a Possible Resource for Fisheries: The Case Study of Caranx rhonchus Geoffroy Saint-Hilaire, 1817, in Southern Italian Waters

Climate change affects the shift range distribution of species, especially among mobile species, and this phenomenon can alter ecosystems and impacts human activities. Fishing is an anthropic activity that undergoes the effect not only of the introduction and increase of non-native species but also of native thermophilic ones. Some of these species can become a commercially exploitable resource. However, this information is often obscured by the negative effects these species can cause to the environment. We investigated how the thermophilic species Caranx rhonchus, neglected in Italy, could become a relevant resource. We studied the nutritional profile and the presence of heavy metal contamination and compared these traits with those of a similar common Mediterranean species, namely Trachurus trachurus. The proximate composition was determined following the AOAC procedure, while the fatty acid profile was determined by GC/MS, and the mineral component was obtained by mass spectrometer (ICP-MS). Caranx rhonchus is a nutritionally good species, although it is little consumed and exploited. Increasing the market supply with new commercially exploitable emerging species would benefit local communities and the environment. Therefore, it is necessary to investigate how a shift of the range caused by climate change can provide benefits within the human dimension.

Mineral and proximate composition of the meat and shell of three snail species

Meat is a vital source of nutrients for human wellbeing and health; however, recent studies suggest a decline in meat preference as a protein source due to some health problems associated with meat intake. This study evaluates the levels of essential elements (Mn, Mg, P, Ca, K, Cu, Na, Zn and Fe) and proximate composition (protein, fat, moisture, carbohydrate, fibre and ash) of three snail species namely; Achatina achatina, Achatina fulica and Archachatina marginata species from the Kumasi Central Market. The mineral content and proximate composition of the three land snail species' shell and meat were analysed using Atomic Absorption Spectrometry and other Standard Methods of Analysis. The study revealed that the three snail species differed in the composition of significant nutrients and trace elements in meat. It is evident from this study that the consumption of snail meat can promote good human health, with Archachatina marginata having the best nutritional value. In the meat from the three snail species, a strong significant positive correlation between Ca and P levels was observed, and the Cu and Fe (p < 0.05). In both the proximate and mineral analysis, each meat parameter was correspondingly higher than that of the shell for all the snail species, except for ash and Ca contents. The estimated daily intakes of Zn, Fe, Mn and Cu were lower compared with the tolerable daily intake, suggesting that the essential elements are at acceptable levels. Therefore, consumers of these land snails will gain the benefits of the proximate and mineral constituents. The shells can also be utilised as food supplements for livestock and eliminate the burden of managing snail shell waste.

Hazard Identification Related to the Presence of Vibrio spp., Biogenic Amines, and Indole-Producing Bacteria in a Non-Filter Feeding Marine Gastropod (Tritia mutabilis) Commercialized on the Italian Market

Tritia mutabilis is a carrion-feeder edible marine gastropod with an open circulatory system. Therefore, biological, and chemical contaminants associated with the feed can reach all body tissues. The aim of the present study was to investigate the possible association of these characteristics with some food safety hazards. Vibrio spp. load, and the prevalence of pathogenic V. parahaemolyticus, V. vulnificus, and V. cholerae, were investigated. Moreover, biogenic amines (BAs) and indole-producing bacteria (IPB), markers of seafood decomposition, were quantified for the first time in an edible carrion-feeder. Overall, 49 batches were analyzed (38 from retail, and 11 from primary production). The Vibrio spp. load resulted of 5.64 ± 0.69 log₁₀ CFU g⁻¹ at retail, and 5.27 ± 0.74 at harvest but all batches resulted negative for pathogenic Vibrio. Histamine, putrescine, cadaverine, and tyramine were detected both at harvest and at the retail level. Their sum (BAs Index) showed a mean value of 50.45 and 65.83 mg Kg⁻¹ in batches at harvest and at retail, respectively. IPB were detected at harvest and upon refrigeration for three days (T1–T3). The mean load resulted in 2.52 ± 0.85 log₁₀ MPN g⁻¹ at T0, 3.31 ± 1.23 at T3 in batches immediately refrigerated, and 3.22 ± 1.18 at T3 in batches previously immersed in clean seawater. Our results contribute to identifying food-borne hazards for T. mutabilis that may be related to the retention of biogenic amines and indole-producing bacteria due to carrion feeding.