Growth performance and physiological responses of Physa acuta fed on  Lemna minor Under Laboratory Conditions

Ahmed Y. Lafta Hzaa

Authors

Hzaa et al., 2026 Department of Marine Biology, Marine Science Centre, University of Basrah

Keywords:

Food Consumption, Growth, Laboratory Experiments, Lemna Minor, Physa Acuta

Abstract

The study aimed to evaluate the effect of feeding snails on the plant Lemna minor on growth and food consumption indicators of the snail Physa acuta, comparing the responses of two groups of snails collected different sites from of Baghdad and Basra. The nutritional treatments included a control treatment using lettuce and two treatments with Lemna minor at levels of 0.020 and 0.040 g. Growth indicators, daily food consumption rate and behavioural and vital observations within the tanks. The results showed significant differences between the nutritional treatments in growth and food consumption indicators, as the addition of Lemna minor led to gradual improvement in snail performance compared to the control treatment. A level of 0.040 g recorded the highest values for the rate of increase in length, reaching 2.12 and 3.88 mm in Baghdad and Basra, respectively. Moreover, the highest rate of increase in weight was 0.0263 and 0.0393 g , in addition to the highest specific growth rates for length and weight. The same level also recorded the highest daily food consumption rate, reaching 3.84 and 4.12 mg dry weight/snail/day in Baghdad and Basra, respectively. The snails from Basra showed relatively higher values for most growth and consumption indicators compared to the snails from Baghdad, especially at the level of 0.040 g. The results indicate that increased availability of Lemna minor at the tested levels was associated with improved food consumption and growth performance of P. acuta, with the 0.040 g level being the best among the studied treatments. These results support the potential use of L. minor as a plant-based food source in studies on the breeding and growth of Physa acuta under experimental conditions.

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