حياتية القوقع الدخيل Pomacea canaliculata Lamarck, 1822 في شط العرب - محافظة البصرة == Biological of the Invasive Snail Pomacea canaliculata (Lamarck, 1822
Author name:
نادية جعفر كاظم البغدادي
General topic:
Biology
Specific topic:
Life Science
Degree:
Master
University:
University Of Basrah - College Of Education For Pure Sciences
Language:
Arabic
University location:
Basrah
First pages:
24T3574 - p.pdf
Abstract:
The present study was concerned with some biological aspects of the invasive snail Pomacea canaliculata (Lamarck, 1822) and for this purpose, monthly samples from Shatt Al - Arab banks in the area of Al - Salhia were collected during the period from October 2014 to September 2015. The study included the monthly variations in the density of snail , its egg masses and the population sizes. In the laboratory, the study included many aspects, these are the relationships between female weight with some measurements of its egg masses, embryonic development duration, hatching percentages under different temperatures, food consumption, salt acclimatization, growth under combined effect of salinity and temperature, effect of food type on growth of newly hatched snails and examine samples of snail to detect the infection with parasites if present. The density of the snail was ranged from four to 13 ind. /m2 recorded during January - February 2015 and October 2014 respectively, while the mean density of egg masses was from two to nine egg mass / m2 recorded during April 2015 and October 2014. The statistical analysis showed that the temperature had positive correlated with density of each of snails and its egg masses. On the otherhand, there are positive correlation between the density of each snail and its egg masses. The snails, which had been collected during the study period, were 19 - 68 mm in length, these measurements were classifying into five size classes. The size class 35 - 45 mm was dominanted for nine months, compared with the size class 55 - 65 mm that had less occurrence.The diameter of eggs varied from 2.5 - 4 mm. The 25°C is the most suitable temperature to get a high percentage of hatching and a short period of embryonic development. There was no significant correlation between the weight of the female and the number of its egg masses.The feeding experiment showed that the amount of food consumed lettuce mild during the study period 30 days by one individual ranged from 3 - 29g. The results of the acclimatization was referred to the ability of all size classes' snails to tolerate the low salinity 2.5 psu with 100% survival percentage, while the snails of size classes at least 10 mm and 10 - 25mm were able to tolerate the salinity of 11psu with 10% and 50% respectivly survival.There are variable effects of the combination of temperature and salinity on growth of newly hatched snails for 9 weeks experiment, these effects were reflected on the weight, length and width, and the highest of these measurements were recorded for snails of 2.5 psu - 27°C combination, while the lowest one was recorded in 7.5 psu - 10°C. The lowest survival percentage was 5% recorded for the individuals of 7.5 psu - 27 and 32°C, compared with 90% of distil water - 17°C. On the other hand, the optimum growth was in 2.5 psu all temperatures, while the optimum growth was in all salinities, and temperature of 27°C.The experimental study of five types of food fresh celery, fresh lettuce, fish food, mixed food and animal protein)on growth of newly hatched snails for 9 weeks. Showed that the mean weight, length and width of snails were depending on the food type. The mixed food gave significant increase in growth 382.1 mg weight, 10.10mm length and7.58mm width compared with the other types of food.The highest survival percentage 95% was recorded for the snails fed on celery, lettuce and fish food. The present study on the snail P. canaliculata does not record any infection by the larvae of parasites
