Impact on Feeding and Growth Rate of Millipedes and Their Conservation Needs in Cauvery Delta Region of Kumbakonam, Tamil Nadu
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MOJ Anatomy & Physiology Research Article Open Access Impact on feeding and growth rate of millipedes and their conservation needs in Cauvery Delta Region of Kumbakonam, Tamil Nadu Abstract Volume 6 Issue 6 - 2019 Diplopoda (millipedes) is one of the largest classes of animal kingdom belonging to Veeramani A, Ramkumar R, Keerthika M the Devonian period constituting the third largest group after Insecta and Arachnida in PG and Research Department of Zoology, Government Arts terrestrial arthropods. These diplopods play an ample role in soil formation being involved College (Autonomous), India both physical and chemical factors. In addition, millipedes can be as a bio-indicator for environmental changes in ecosystems. A study on millipedes such as Yellow-spotted Correspondence: Veeramani A, PG and Research Department (Harpaphe haydeniana), Red-spined (Xenobolus carnifes), Colossal slender spined of Zoology, Government Arts College (Autonomous), (Spinotarsus colosseus) and American giant, (Narceus americanus) were conducted along Kumbakonam, 612 002, Tamil Nadu, India, Tel 8124881520, the bank of Cauvery River in Kumbakonam region. The present study is intended to find out Email to know the impact on food intake and the growth rate of millipedes by artificial feeding of decomposed dry leaves and the amount of milli casts (faecal) produced of millipedes under Received: August 24, 2019 | Published: December 05, 2019 captive condition. The experiment was carried out during the monsoon season and hand picking of millipedes were done. Ten numbers each of four species of millipedes were kept in separate plastic jars. Dry and decayed leaves were weighed and kept inside the plastic jar as food for millipedes. Before starting the experiment all the individuals of the millipedes were weighed separately and inserted in to the jars. The milli cast deposited by millipedes were separated and weighed to know the production of amount of milli casts. In the case of Harpaphe haydeniana the increase of body weight of 10 individuals shows that there is significant differences between the individuals (F=0.1308, df=8.141, p=0.9969). Xenobolus carnifex shows that there is about 25% of the weight increase among the individuals (F=0.1385, df=8.134, p=0.9962). Spinotarsus colosseus the increase of body weight of 10 individuals shows that there is a significant differences between the individuals (F=0.05101, df=8.142, p=0.9999). Narceus americanus the 90 days period of experiment shows that there is about 25% of the weight increase among the individuals (F=0.1308, df=8.141, p=0.9969). It is suggested that the results of this experiment can be applied to millipedes in their natural setting, further confirming millipedes as important components of soil ecosystems and nutrient cycling. Keywords: millipedes, body weight, food intake, milli cast, conservation, Cauvery Introduction These diplopods play an ample role in soil formation being involved both physical and chemical factors. Physical disruption The saprophagous macrofauna (eg. millipedes, earthworms, of the upper layer of the soil and the litter noticeably enhances the slugs) are mainly responsible for increased nutrient leaching from burrowing activities of both adult and larval stadia. Many immature 1,2 dead plant organic matter and enhancement of soil humification. stadial durations are completed in the humus layer of the soil itself. Diplopoda (millipedes) is one of the largest classes of animal kingdom Chemical influences of these animals on soil are of several kinds belonging to the Devonian period constituting the third largest group (1) modification of plant material through digestion (2) uptake 3,4 after Insecta and Arachnida in terrestrial arthropods. Based on the and concentration of calcium and other minerals and (3) release of body structure, five morphotypes have been identified in millipedes nitrogenous compounds from metabolic excretion and formation of 5 by Kime & Golovatch . Polyxemda (bristly millipedes or bark- weak organic acids as the result of death and protein breakdown.9 dwellers), Glomenda (pill millipedes or rollers), Julida (bulldozers or South Indian millipedes are known to feed on soil and litter in varying rammers), Polydesmida (wedge or litter-splitters) and Platydesmida stages of decomposition. Most of the tropical millipedes are known to (borers). Millipedes occupy three major habitats in forest ecosystem aestivate during drought, their distribution and period of activity are (the aerial part of vegetation, bark and rotten woody stumps, litter and dependent on humidity and water resources of the soil. Many of these 6 soil strata). also feed on green vegetable matter and in the absence of the litter Similarly, they also exhibit horizontal distribution depending on they switch over to utilization of soil, rich in rotting organic matter. the diversity and quantity of plant litter on the forest floor or soil. Millipedes are functionally important in facilitating nutrient cycling Unlike earthworms and woodhce, millipedes are conservative and and decomposition of dead plant tissues. In addition, millipedes can very sensitive to water deficit and fail to overcome the limitation of be a bioindicators for environmental changes in ecosystems. There even a single edaphic factor (eg soil texture, litter thickness) although is no study on millipedes were reported in the Cauvery delta region, 5 rest of the ecological conditions are conducive. Millipedes are more even though we have many species of millipedes present here. abundant in Western Ghat forests than in grasslands or coastal habits There is a study on diversity of millipedes were reported in Alagar due to relative abundance of litter biomass.7,8 Submit Manuscript | http://medcraveonline.com MOJ Anat & Physiol. 2019;6(6):205‒212. 205 ©2019 Veeramani et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and build upon your work non-commercially. Copyright: Impact on feeding and growth rate of millipedes and their conservation needs in Cauvery Delta Region 206 of Kumbakonam, Tamil Nadu ©2019 Veeramani et al. Hill Reserved Forest, Madurai by Alagesan & Ramanathan10. Apart were weighed separately and inserted in to the jars. Regular weight from this studies are meager in Tamil Nadu particularly in Cauvery of the millipedes was taken to know the growth. Similarly same delta region. Hence a study on millipedes such as Yellow-spotted quantity of dry and decayed leaves were weighed and kept inside (Harpaphe haydeniana), Red-spined (Xenobolus carnifes), Colossal the jars and water was sprayed for make wet of the leaves. Feed was slender spined (Spinotarsus colosseus) and American giant, (Narceus given whenever the leaves were fed by millipedes. Care was taken americanus) were conducted along the bank of Cauvery River in to provide same quantity of leaves at every time. Every 15 days of Kumbakonam region with the objectives of the growth rate of four interval the unfed leaves were weighed and removed. The faeces different species of millipedes under captive condition, food intake (milli cast) deposited by millipedes were separated and weighed to of millipedes by artificial feeding of decomposed dry leaves and the know the production of amount of milli casts. The same procedure amount of milli casts (faecal) produced by four different millipede was continued till the end of the experiment. Digital weighing balance species. was used to estimate the accurate weight of millipedes and feed. Materials and methods Based on these experiment, data were collected on amount of food intake and milli cast produced by millipedes. Also the increasing Kumbakonam is located at 10.97°N 79.42°E. It lies in the region trend of body weight of millipedes was also collected. Care was called the “Old delta” which comprises the north-western taluks of taken to remove and weighing of the millipedes, because of some Thanjavur district that have been naturally irrigated by the waters of imperfections such as defensive body secretions on the tweezers and the Cauvery and its tributaries for centuries in contrast to the “New water condensation on the tweezers’ fingers may have occurred. The Delta” comprising the southern taluks that were brought under average difference between the calculated weight of all the species irrigation by the construction of the Grand Anicut canal and the of millipedes was used to correct the directly measured weight gain. Vadavar canal in 1934. It has an average elevation of 26 metres. The town is bounded by two rivers, the Cauvery River on the north and In order to calculate the consumption index (CI) the formula of 11 Arasalar River on the south (Figure 1). Waldbauer was slightly modified: CI = intake/ ( initial weight + final weight) /2 (1) The efficiency of conversion of ingested food (ECI; %) into body substance of the millipedes of each jar was calculated using Equation 2:11,12 ECI = 100 weight gain( in g) / intake( in g) (2) Initial body weight per 10 millipedes (at t=0), their weight after 15 days (at t=15), food intake, body weight gain, and CI and ECI were calculated. The computer programme PAST and MINITABT was used for the statistical analyses. Results Growth rate The results collected for 90 days from mid December 2019 to mid March 2019 on four species of millipedes shows that there is a considerable increase of growth from the initial and final weight of the experiment. In the case of Harpaphe haydeniana the increase of body weight of 10 individuals shows that there is significant differences Figure 1 Map of Cauvery delta at Kumbakonam and surroundings. between the individuals (F=0.1308, df=8.141, p=0.9969). Similarly more than 50% of the body weight increase were seen some of the The experiment was carried out during the north-west monsoon individuals (Table 1). (December–January) and post monsoon (February and March) when millipedes are available in large numbers. Hand picking of millipedes The graph showing that the difference between initial and final were carried out to conduct the experiment.