Agrahari P, Singh D K
Malacology Laboratory, Department of Zoology, DDU Gorakhpur University, Gorakhpur, UP, India.
Zoonoses Public Health. 2013 Nov;60(7):478-86. doi: 10.1111/zph.12024. Epub 2012 Nov 21.
Laboratory evaluation was made to access the seasonal variations in abiotic environmental factors temperature, pH, dissolved oxygen, carbon dioxide, electrical conductivity and ferulic acid toxicity in snail-attractant pellets (SAP) against the intermediate host snail Lymnaea acuminata in each month of the years 2010 and 2011. On the basis of a 24-h toxicity assay, it was noted that lethal concentration values of 4.03, 3.73% and 4.45% in SAP containing starch and 4.16, 4.23% and 4.29% in SAP containing proline during the months of May, June and September, respectively, were most effective in killing the snails, while SAP containing starch/proline + ferulic acid was least effective in the month of January/February (24-h lethal concentration value was 7.67%/7.63% in SAP). There was a significant positive correlation between lethal concentration value of ferulic acid containing SAP and levels of dissolved O2 /pH of water in corresponding months. On the contrary, a negative correlation was observed between lethal concentration value and dissolved CO2 /temperature of test water in the same months. To ascertain that such a relationship between toxicity and abiotic factors is not co-incidental, the nervous tissue of treated (40% and 80% of 24-h lethal concentration value) and control group of snails was assayed for the activity of acetylcholinesterase (AChE) in each of the 12 months of the same year. There was a maximum inhibition of 58.43% of AChE, in snails exposed to 80% of the 24-h lethal concentration value of ferulic acid + starch in the month of May. This work shows conclusively that the best time to control snail population with SAP containing ferulic acid is during the months of May, June and September.
进行了实验室评估，以了解2010年和2011年各月份非生物环境因素（温度、pH值、溶解氧、二氧化碳、电导率和阿魏酸毒性）对中间宿主尖膀胱螺的诱螺剂颗粒（SAP）的季节性变化情况。基于24小时毒性试验，注意到在5月、6月和9月，含淀粉的SAP的致死浓度值分别为4.03%、3.73%和4.45%，含脯氨酸的SAP的致死浓度值分别为4.16%、4.23%和4.29%，这些浓度在杀死蜗牛方面最为有效，而含淀粉/脯氨酸+阿魏酸的SAP在1月/2月效果最差（该月份SAP的24小时致死浓度值为7.67%/7.63%）。含阿魏酸的SAP的致死浓度值与相应月份水中溶解氧/pH值水平之间存在显著正相关。相反，在同一月份，致死浓度值与试验水中溶解二氧化碳/温度之间呈负相关。为确定毒性与非生物因素之间的这种关系并非偶然，在同一年的12个月份中，对处理组（24小时致死浓度值的40%和80%）和对照组蜗牛的神经组织进行了乙酰胆碱酯酶（AChE）活性检测。在5月，暴露于阿魏酸+淀粉24小时致死浓度值80%的蜗牛中，AChE的最大抑制率为58.43%。这项工作最终表明，使用含阿魏酸的SAP控制蜗牛种群的最佳时间是5月、6月和9月。
