| The Kalamaili Nature Reserve (KNR) in Xinxiang, China is one of the few places in the world where the habitats of different wild equids overlap, and is an important area where Przewalski’s horse, Mongolian wild ass, and domestic horse live sympatrically,and share pastures seasonally. Gasterophilus is the mainly parasitic infection disease for the above three kinds of equid, and repeated infection every year. If there is a correlation in difference habitat selection for three kinds of equid with the infection species and quantity for the bot flies. What actions lead to the bots was high incidence and repetitive in the region was become the focus of this study. The result showed that through to the study behavior between the horses and bot flies:(1) Some characteristics from the bot flies supply the condition for adapting endoparasite. Hook and thorns were specialized and become more advanced, can enhance the adhesion ability for the inner surface of the digestive tract, prevent to be excreted to the outside of the body because of gastrointestinal peristalsis; Epidermal keratinization can resist the role of host digestive enzymes, epidermal covering chitin body wall, can reduce the water evaporated.(2) There were correlations between phenotypic traits and behavioral characteristics of three instar larvae. Interspecific coefficient of variation in embedded depth (25.25%)> peristaltic crawling (25.09%)> speed frequency (24.60%)> weight (22.75%), the grave time (20.75%)> length/breadth (19.16%)> three instars breadth (13.95%)> three instars body length (13.03%) among 6 kinds of Gasteropjilus three instars. The six kinds of bot flies are divided into three classes according to the morphological characteristics and behavior index. G.inermis (Gin), haemorrhoidalis (Gh) and G. intestinalis (Gi) become a cluster. G. nasalis (Gn) and G. nigricornis (Gni) become another cluster. G. pecorum (Gp) alone form a cluster. The three instars recognition and identification were may be completed according to the phenotypic traits and behavioral traits.(3) First found the G. pecorum’s oviposition habitat. The result showed that G. pecorum’s oviposition habitat was preferentially on slopes with inclinations of 10-30° that were semi-sunny, semi-cloudy slopes, in positions high or low on the slopes, with preferences for total plants lower than 10% and Stipa capillata coverage lower than 10% on the low slopes, but Ceratoides latens coverage on the high and intermediate slopes, when the numbers of plant species and families were lower than five. G. pecorum often selected sites at a distance<2000 m from a water source and average altitude 900-1000 m. The oviposition site selection by G. pecorum may be correlated with the behaviour of Przewalski’s horses (Equus ferus przewalskii), and water and food resources may strongly influence oviposition site selection, as Przewalski’s horses rest and forage in these areas.(4)Comprehensive analysis why G. pecorum become the local dominant species. G. pecorum mainly lay their eggs in the grass, and the other horse bot flies mainly lay their eggs on the horse hair. In xinjiang arid desert grassland, food and water is the restrictive factor for animal survival distribution, with a high proportion of eggs in the grass. The risk was higher than other regions for equid who feed the grass where were attached eggs. What’s more, the infection efficiency lay their eggs in grass for Gasterophilus is higher than on the host animal hair.(5) Analysis of the different Gasteropjilus infection among three kinds of equid. The result showed that six of the nine known Gasterophilus species occur in equinefrom KNR, China. Most equines were infested by five (35.57%) orfour (32.22%) Gasterophilus species; There were difference significant (P< 0.01) in habitat choice location and scope of the activity and migration path between Przewalski’s horses and wild donkey, as a bot flies in repository, the contribution rate of wild spread was more than the Przewalski’s horses. |
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