Studies On Fecal Steroids And Immunoglobulin Of Crested Ibis (Nipponia Nippon)

As a world’s endangered species, the living status of Crested Ibis (Nipponia nippon) has been a key field in conservation biology research, and it has attracted a wide attention. Studying the steroids and immunoglobulin of Crested Ibis plays an important role in the analysis of its reproductive physiology, stress response and immune physiology and is important for its protection. Because of the study of endangered wildlife has its specificity, invasive sampling methods like collecting blooding from Crested Ibis is not suitable for the discipline development, more and more researchers have been paying attention to the noninvasive measuring method.The aim this study was to use feces as the noninvasive material, to investigate and establish the method for the extraction and analysis of steroids and Immunoglobulin in t Crested Ibis feces. Measuring the amount of steroids and Immunoglobulin in the feces of Crested Ibis adults, sub-adults and nestlings, and provide some preliminary data for the conservation and routine monitoring of Crested Ibis. Measuring and analyzing the level of sex hormone in the feces of Crested Ibis during breeding season and non-breeding season to explore its regulate function. In addition, the amount of cortisone and immunoglobulin in feces of Crested Ibis during New Year’s season was measured, to find out the disturbance of tourists to Crested Ibis. We collected feces at Shaanxi Wildlife Breeding Center from February2011to February2012, and all samples were transported to laboratory for analysis.The main results are as follows:1ELISA (Enzyme-linked immunosorbent assay) of samples with different methanol proportion showed when methanol propotion is over10%, the results will be significantly affected. Therefore it is suggested that the sample be diluted at least20times in phosphate buffer solution (PH=7.4,0.02M) before the ELISA was performed.2Analysis of IgA in Crested Ibis feces showed there is no significant differences between sexes (P=0.090) and ages (P=0.938) in adult and sub-adult Crested Ibis. But the amout of fecal IgA in Crested Ibis nestling febes is significantly higher than the amount in adult Crested Ibis (P=0.005). The amout of IgA in the feces of Crested Ibis nestling showed an increasing tendency before day25and then reduced, and finally became stable.3Analyzing the amout of cortisone in the feces of Crested Ibis showed that there is no significant differences between sexes (P=0.423), but the amount of cortisone in adult and sub-adult Crested Ibis showed significantly difference (P=0.016). The amount of cortisone of Crested Ibis nestling is significantly higher than the amount in adult (P=0.004) and sub-adult (P=0.007). We presume that age is one of the influencing factors of stress response in Crested Ibis.4The analysis results of the amount of cortisone and IgA in Crested Ibis feces showed there is a correlation between the amount of cortisone and IgA. Low level of cortisone is benefical for immuno enhancement while high level of cortisone inhibits the production of immunoglobulin.5The amount of cortisone in Crested Ibis feces is significantly correlated to the number of tourists. There is no significant difference (P=0.509) of feces amount between the Crested Ibis in the exhibition cages and in cages next to the large netting cage, where there were less tourists. The tourist number should be controled to avoid serious stress response in Crested Ibis.6Fecal estradiol testosterone and progesterone were measured in Crested Ibis of both sexes during different phases during a whole year. The results showed stage change in all of the tested sex hormones. The amount of estradiol was higher during the pre-courtship and courtship period and declined after egg laying in female Crested Ibis.The amount of testosterone started to increase from the egg laying and declined after egg laying in female Crested Ibis.The amount of testosterone started to period and kept in a high level during incubation period. The amount of progesterone was higher in brooding period. In male Crested Ibis, the amount of estradiol was relatively stable, but the amount of testosterone reduced during the mating period and kept in high level during the incubation and brooding periods. The change of progesterone amount in male Crested Ibis was as same as that in female Crested Ibis.In brief, sex hormone can regulate the physiology of Crested Ibis and function as indicators for the reproductive and physiological states of Crested Ibis.