Shells continue to grow with the snail over the course of its life. Therefore, they need to feed themselves to get calcium, and the first source to get it is by consuming the remains of their egg and even other eggs that have not yet hatched. Under favorable conditions, eggs hatch after approximately two weeks to 1 month and snails emerge with a soft shell.
The shell of the snail develops since it is an embryo inside its egg. Even humans take them, which are known as white caviar or snail caviar, consumed in some regions of the world. Many of the eggs are washed away by rain or water or eaten by predators, despite the outer protective layer and being resistant to cold and heat. They usually have a diameter between 3 and 6 millimeters.Įven with so many eggs produced, only a fraction of these snails reach maturity. Once the snail has the proper place, it puts the 100 small and round eggs, often white, surrounded by a viscous layer that serves as protection. If it is in the soil, the animal digs with the aid of its ventral foot until obtaining a hole with a depth of 2 to 4 inches. It can take up to four weeks for them to hatch.īefore laying their eggs, some snails build a nest in a hole, between vegetation or on the ground. These eggs are tiny, and they will be dropped into moist soil and covered. As they are promiscuous animals, they can store sperm from previous couples for a long time, even years.Īfter the mating process, both snails will produce around 100 eggs, but some species can have up to 400. Laying the eggs happens in the following days, but the time varies according to the species. However, after the mating, both snails can deliver a set of eggs which increases the chances of survival. Then, the sperm enters the body of the other snail to fertilize the eggs later.Įven though snails are hermaphrodites, they mate in the traditional way, they do not fertilize themselves. The sperm is transferred using a penis or spermatophore exiting the body during the intercourse. During copulation, both individuals can transfer sperm to each other, but it does not happen in all cases. Snail breeding involves sexual reproduction. Snails will produce around 100 eggs, but some species can have up to 400. Once the mating is over, they go in separate directions. So they expel some chemicals to attract others ready to mate and use touching as a way of courting. They don’t make sounds to lure each other like many types of animals do because snails don’t have the ability to hear. They can last breeding from a couple of hours to half a day. Land snails engage in various types of courting rituals to attract mates. And third, they have the habit of shooting some structures called “love darts” just before mating. Second, on most occasions, two individuals copulate rather than self-fertilize. First, most of these gastropod mollusks are hermaphrodites so that a single snail may have male and female reproductive organs. Reproduction of land snails is carried out under odd circumstances. The breeding process of snails has some unique features when compared to other land animals. The age of sexual maturity is variable from 6 weeks to 5 years, depending on species of snail. In brief, the snail life cycle has the following steps: As this is the first report in our country in respect to the life span and cercariae shedding of infected snails in a mountain region, the result might be useful for quantitative analysis of epidemiological factors of schistosomiasis in this kind of endemic areas as well as for formulation of control strategy.The life cycle of any animal is the period involving the succession of one generation to the next through reproduction. It was estimated that the average patent period of infected snails was over half a year. The average number of cercariae shed per snail in its whole life was 673.0. The average life span of infected snails was 171.6 days. The snail survival rate from the day of initial cercaria shedding to next June, July, August and September was 27.4, 16.3, 13.3 and 11.9% respectively, and the average number of cercariae shed was 139.9, 29.6, 39.2 and 75 per month respectively. 135 infected snails were isolated for observation 3 months after exposure to miracidia in August, 1987.
The life span and cercaria shedding of infected Oncomelania snails in a mountain region of Shitoudi village, Weishan County, Yunnan Province were observed in simulated local ecological environments.
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