Aquaculture Challenges: Calceostoma glandulosum and Meagre

Researchers Maria Carolina Ribeiro and Teresa Baptista are co-authors of the article “First Report of Calceostoma glandulosum (Monogenea) in Argyrosomus regius: Morphological and Molecular Characterization and Temperature Effects on Life Cycle”, the result of the first characterization of the Calceostoma glandulosum parasite, which frequently affects meagres reared in aquaculture

The growing demand for food, driven by the increase in the world's population, has led to a significant increase in fish production in aquaculture. This growth, although necessary, brings with it a series of challenges, usually related to the intensification of production systems. Increased stocking densities in ponds cause stress in fish, weakening their immune systems and making them more susceptible to disease outbreaks, particularly those caused by parasites.

Among the parasites that affect fish produced in aquaculture are the so-called “monogenetic parasites”, those that develop in a single host. These ectoparasites, which attach themselves to the external surfaces of fish, are highly host-specific, affecting one of the main species on the rise in Mediterranean aquaculture, the Meagre (Argyrosomus regius). Appreciated for its high-quality meat and excellent growth rate, this species is extremely vulnerable to parasitic diseases due to a lack of knowledge about them. 

In this context, a recent study by MARE researchers Maria Carolina Ribeiro and Teresa Baptista sheds new light on this problem. The study presents the first morphological and molecular characterization of Calceostoma glandulosum, an ectoparasite of the Monopisthocotylea subclass frequently found in corvinas. This parasite is distinguished by the presence of a lapel in the cephalic region and an anchor-shaped haptor (host attachment structure). The life cycle of C. glandulosum, which includes eggs, larvae (called oncomiracids) and adults, was described in detail in the study, providing a deeper understanding of its biology and its impact on aquaculture.

The research also revealed that water temperature plays a key role in the development of C. glandulosum eggs. Higher temperatures favor hatching, with a 100% hatching rate at 23°C. The presence of the parasite in the culture tanks was more common when the temperature reached 20°C, which suggests that environmental conditions may be a determining factor in the spread of the parasite.

To assess the specificity of C. glandulosum for meagres, the researchers also studied the presence of the parasite in other species, such as Sparus aurata Diplodus sargus Seriola rivoliana. The results indicated a strong preference of the parasite for the meagre, which highlights the importance of specific strategies for the management of this species in aquaculture.

This study provides valuable information on the behavior of C. glandulosum in relation to environmental conditions and interaction with its host, allowing for the development of more effective prevention and control strategies in aquaculture systems. In addition to expanding knowledge about the parasites that affect corvina, these findings have the potential to improve fish health and the sustainability of aquaculture production, a vital sector for global food.

 

To access the article click HERE