Effects Of Plant Secondary Metabolites On The Feeding Behavior Of Plateau Pika

Using indoor cage raising experiment, the effects of two plant species containing higher plant secondary metabolite on feeding behavior of plateau pika were investigated. Two plant species were Cicuta virosa(rich in coniine)and Potentilla anserine(rich in tannin). Feeding behaviors of plateau pikas observed were food intake, meal number, inter-meal interval, water intake, and body mass. Furthermore, the relationship between water intake and body mass was also analyzed. The main conclusions were as follows:1.The concentration of C virosa and P anserine in diets had significant effects on total food intake of pikas. As the concentration increased, both of the total food intake decreased significantly, for C virosa, decreased from 48.6 g to 19.8 g, for P anserine, decreased from 51 g to 36.6 g). There were negative correlations between them. The falling range for P anserine, however, was smaller than that of C virosa. This result indicated that the pika could better adapted to P anserine.2. The concentration of C virosa and P anserine had different effects on meal numbers of pikas. With the increase of C virosa concentrations, meal number of pika increased from 17 to 21, and there were positive relationships between concentrations and meal numbers. The variation of P anserine concentration, however, had no significant effects on meal numbers of pikas. This result suggested that pika was able to make the adaptive response to food with higher toxicity.3. The concentration of two plant species had different effects on inter-meal interval of pikas. With the increase of C virosa, inter-meal interval of pika reduced from 11 min to 8.7 min. There was a negative corelation between them. Unlike this variation, there were no significant correlations between P anserine concentration and inter-meal interval of pika.4. The concentration of two plant species had different effects on water intake of pikas. The concentration of C virosa had negative effect on water intake(reduced from 25 g to 20 g), while P anserine had no effect on water intake of pika.5. At the end of experiment, both of the plant had significant negative effects on body mass of pikas. From this result, we can see that, whether it is C virosa(coniine) or P anserine(tannin), all had certain toxic effect on plateau pika when their concentration in diet reached a higher level.6. Under the different treatment of experiment, the relation patterns between water intake and body mass were different. For C virosa, there existed positive correlations between water intake and body mass. For P anserine, however, there were no significant correlations between the two factors.