The Effect of Ag Nanoparticles and Multimicrobial Preparation as Factors Stabilizing the Microbiological Homeostasis of Feed Tables for Cornu aspersum (Müller) Snails on Snail Growth and Quality Parameters of Carcasses and Shells

Edible Snail Production in Europe

Simple Summary

Edible snails are a good source of easily digestible nutrients. They are easy to breed and their farming is more environmentally friendly than traditional livestock: they need little space, use less feed per kg of growth, and emit significantly less greenhouse gases. This review aims to present the most important issues related to the breeding of edible snails in European conditions: their importance, maintaining systems, the value of meat and caviar, and the feed used during the animals’ rearing and fattening period.

Abstract

The human population is growing; food production is becoming insufficient, and the growing awareness of the negative impact of traditional animal husbandry on the environment means that the search for alternative methods of providing animal protein is continuously underway. The breeding of edible snails seems to be a promising option. The most popular species of edible snails in Europe include the brown garden snail Cornu aspersum (Müller, 1774) (previously divided into two subspecies: Cornu aspersum aspersum (Müller, 1774) and Cornu aspersum maxima (Taylor, 1883)), as well as the Roman Snail—Helix pomatia Linnaeus, 1758. These animals are highly productive, require relatively little space, are easy to breed and their maintenance does not require large financial outlays. This review focuses on the prospects of food snail farming in Europe. It discusses the living conditions, the nutritional value of the snails’ meat, and the way of feeding the animals, paying particular attention to issues still not scientifically resolved, such as the need for micro and macro elements, as well as fat and carbohydrates.

Impact of Ag Nanoparticles (AgNPs) and Multimicrobial Preparation (EM) on the Carcass, Mineral, and Fatty Acid Composition of Cornu aspersum aspersum Snails

The hygienic practices on farms should reduce pathogenic microorganisms while simultaneously not harming the animals themselves; they must also not degrade the products' quality. We assessed the effect of covering feed tables with paint containing silver nanoparticles (AgNPs) and the periodic spraying of effective microorganisms (EM) on production indicators and basic chemical composition, mineral content and fatty acid profiles in the bodies of Cornu aspersum aspersum snails. The animals were divided into four groups: (1) control, (2) with feed tables covered with AgNPs paint, (3) with EM spray applied and (4) with both factors-AgNP paint and EM spray. The highest increase in Ag, Zn, Fe and Ca retention, and the remodelling of the fatty acid profile in the carcasses of snails was found to be in the group of animals in contact with the feed tables covered with AgNP paint. In the group of animals exposed to the action of EM, an increased retention of Fe, Cu, P, Mg and Zn was found.

The "Sandwich" System: A Potential Solution for Protecting Overwintering Cornu aspersum Snails Reared in Semi-Intensive Heliciculture Farms in Colder Climates

Simple Summary

The Italian semi-intensive (ISISF) technology is widely used for rearing the Mediterranean snail, Cornu aspersum. It relies on protecting overwintering specimens with Lutrasil frost cloth (LFC). This approach yielded elevated mortalities in Romanian snail farms. We aimed to develop a simple and effective system for protecting overwintering C. aspersum adults in colder climates. This three-year, three-phase experiment investigated selected behavioral aspects and thermal protection efficiency of different protective structures. Mature gastropods in preparation for hibernation exhibited a significant preference for wood and ridge-tile micro shelters. Soil texture significantly influenced the burrowing behavior, but not the burrowing depth. The structure soil/LFC/straw/10-cm air cushion/high-density polyethylene (HDPE)—the “sandwich” system—was selected to be used as a protective system. Under farm conditions, adult snails tended to hibernate clustered together, attached to the lower surface of micro shelters. The “sandwich” system coupled with using ridge-tile/wood micro shelters resulted in significantly higher survival thanthe sole use of LFC. Predator occurrence appeared to exert a minor effect on snail survival. These data render the “sandwich” system a potential solution for overwintering C. aspersum breeders in colder climates.

Abstract

(1) Background: Hibernation in pens covered with LFC was associated with high mortality of C. aspersum snails in Romanian snail farms. This three-year study aimed to develop a simple, but effective system for protecting breeders in colder climates. (2) Methods: The first phase investigated the (pre)hibernal burrowing behavior and the overwintering habitat choice. Protective structures based on straw, LFC, and/or HDPE were tested at pilot level (no snails). The most suitable system was applied under farm conditions. (3) Results: Wood and ridge-tile micro shelters were significantly preferred to corrugated iron micro shelters. Burrowing specimens acted as shallow-burrowers, and this behaviorwas significantly more common for looser soils. All pilot systems displayed significantly higher thermal protection efficiency compared to the sole use of LFC. The balance between straw moistening and thermal protection favored using structure soil/LFC/straw/10-cm air cushion/HDPE. Its use yielded significantly higher survival compared to the sole use of LFC. Most hibernating snails clustered together in large groups, attached on the lower surface of micro shelters. Predator occurrence appeared to marginally affect overwintering survival. (4) Conclusions: The “sandwich” system could be an effective solution for overwintering mature C. aspersum snails in colder climates.