The Effect Of Kinship On The Breeding And Cannibalism Of Tadpoles In The Tiger Frog (Hoplobatrachus Rugulosa)

The tiger frog (Hoplobatrachus rugulosa), which is one of the animals under state protection Ⅱ was used as the study object to mainly discuss the effect of genetic relationship on the mate choice of tiger frog and the cannibalism behavior of tiger frog tadpoles, and the influence of inbreeding on female reproductive output and the survival and growth of offspring.1. cannibalism behavior of tiger frog tadpolesThe effect of food and temperature on cannibalism behavior of the tiger frog tadpole and the correlation of oral disk width of tadpoles in different Gosner stages and the degree of cannibalism was discussed in this study. A 3 (food gradient) x 2 (temperature) factorial experiment was design:three food gradients (0 g,0.05 g and 0.1 g/800 ml); two temperature treatments (25℃ and 30℃). Two factor analysis of variance shows that temperature has obviously effect on the growth of Gosner stage and body length of predatory tadpoles, and the Gosner stage and body length of predatory tadpoles under 30℃ were significantly greater than those under 25℃; Different amount of food had significantly effect on the Gosner stage and body length of the predatory tadpoles, and with the increase of amount of food, the body length and Gosner stage of predatory tadpole increased; the interaction of temperature and the amount of food had significantly effects on the growth of body length and Gosner stage; One-way ANOVA shows that the body weight, oral disk width, head length, head width and length of predatory tadpoles are significantly different. The body weight, oral disk width, head length, head width and body length of GS40 tadpoles are the biggest, and head length, head width and body length of GS28 tadpoles are minimal. Linear regression shows that Gosner stage was significantly positively related with the number of preyed tadpoles and oral disk width.2. kin-recognition behavior of the tiger frog tadpolesKin-recognition behavior of tiger frog tadpole was studied under the background of cannibalism to explore whether tiger frog tadpole prefer cannibalizing inter-clutch tadpoles or inter-clutch tadpoles, and the effect of kin signal (chemical signals) density on kin-recognition behavior. two-clutch tadpoles were randomly selected as predator and prey (half of the predatory and prey tadpoles were from the same clutch). Before the trial, the predatory tadpoles were under 30℃ and prey tadpoles under 25 ℃, so that the predators were bigger than preys. The results showed that (1) tiger frog tadpoles have kin-recognition ability; (2) the tail injury and death of the tiger frog tadpoles affect kin-recognition behavior; (3) kin signals (chemical signals) density does not affect the kin-recognition behavior; (4) cannibalism does not provide ideal food for tiger frog tadpoles to increase their growth and development.3. the effect of genetic relationship on mate choice and reproductive output of tiger frog and survival and growth of offspring413 pairs of male-female frogs were collected in this study, and there was no significant difference between the pairs of inter-clutch frogs and the pairs of inter-clutch frogs. The pairs of reproductively successful frogs were 71, and there were no significant difference between the pairs of inter-clutch frogs and the pairs of inter-clutch frogs with successful reproduction. The number of eggs of inter-clutch and intra-clutch frogs were no significant correlation with the female body length. The body length and Gosner stage of the offspring of intra-clutch frogs were significantly less than the offspring of inter-clutch frogs. The inter-clutch numbers of successful metamorphosis were significantly less than the inter-clutch numbers. The metamorphosis time of froglets from inter-clutch parents was shorter than the froglets from intra-clutch parents and body length of froglets from inter-clutch parents was larger than the froglets from intra-clutch parents.The results showed that (1) the adult tiger frog does not have the mate choice behavior; (2) inbreeding does not affect the reproductive output of female tiger frogs; (3) the inbreeding is disadvantage for the survival, growth and development of offspring.