Study Of Gastrointestinal Parasites From Giant Panda (Ailuropoda Melanoleuca) And Rhesus Macaque (Macaca Mulatta Lasiotis)

Wild animals are valuable natural resources. The protection of wild animals is the common responsibility of all mankind. Giant panda is the world endangered species, and rhesus macaque (Macaca mulatta lasiotis) is listed in Appendices II of china's national list for specially protected wild animals. Gastrointestinal parasites, is a serious problem for wild and captive populations of giant panda and rhesus macaque.Among all the diseases in the giant panda, parasitosis is the most serious one. While Bayliscaris schroederi (roundworm), represents a significant threat to both wild and captive populations. B. schroederi is the only endoparasite that appears to be consistently recognized in the giant panda. Its infection rate among wild pandas may reach over 50% or even 100%. It has been previously reported that the probability of death of wild pandas being caused by this disease increased significantly between 1971 and 2006. B. schroederi represented the most important cause of death during the most recent period (2001-2005), responsible for 12 out of 24 of the deaths reported. To effectively control parasitic diseases, it is necessary to identify types of parasites. Identification of the traditional types of parasites was mainly based primarily on morphological characteristics. But the traditional method of morphological classification was difficult to accurately reflect the real situation in Ascaris species. The ascarids remain a major health problem worldwide and the feasible strategies for treatment are limited. So far methods for the control of the ascarids infection are mainly based on chemotherapy, but these drugs cause side effect, drug-resistence and drug-remaining.In order to prevent and control the ascarids more effectively, in this study, the mitochondrial gene COX I and COX II were used to determine the taxonomic status of ascarids from Ailuropoda melanoleuca, Ailurus fulgens and four kinds of bears (Ursus maritimus, Ursus arctos pruinosus, Ursus thibetanus mupinensis and Ursus arctos lasiotus). In addition, the gene of Bs-Ag3 from B. schroederi was amplified, cloned and sequenced to study whether the using of Bs-Ag3 as a potential candidate for vaccination against B. schroederi infection is suitable.For the superiority of non-human primates as models compared with other lab animals, macaques were used in many biomedical researches. Basic data on patterns of parasitic infections in wild populations are critical to provide an index of population health and to begin to assess and manage disease risks. In addittion, according to the evolutionary and ecological linkages between non-human primates and their parasites, one can view parasites as indicator species, potentially alerting us to imminent to primate conservation. The objective of this study was to evaluate the prevalence and species of major gastrointestinal parasites in wild-trapped rhesus macaques of the Sichuan province, China, and to evaluate the anthelmintic efficacy of selamectin, ivermectin and mebendazole against the gastrointestinal nematodes in captive rhesus macaques. The results of research are summarized as following:1. Molecular phylogenetic studies of roundworms from giant panda and seven rare wild animals based on COX I and COX II geneThe taxonomic status of roundworms from some rare wild animals has been an open question. The the mitochondrial partial COX 1 and COX II gene of roundworms from Ailuropoda melanoleuca, Ailurus fulgens, Ursus maritimus, Ursus arctos pruinosus, Ursus thibetanus mupinensis, Ursus arctos lasiotus, Pan troglodytes and Hylobates hoolock were sequenced. Homology analyses indicated that the identity levels of COX I genes sequences ranged from 94.8% to 95.0% and COX II genes sequences ranged from 94.9% to 95.5% among roundworms from Ailuropoda melanoleuca, Ailurus fulgens. Ursus maritimus, Ursus arctos pruinosus, Ursus thibetanus mupinensis and Ursus arctos lasiotus, the 99.8% identity levels of nucleotide of COX I and 99.5% identity levels of nucleotide of COX II genes among Pan troglodytes roundworms and Hylobates hooloc roundworms. The alternative trees indicated that roundworms from Ailuropoda melanoleuca, Ailurus fulgens and four species of bears belong to Baylisascaris roundworm, so Toxascaris selenarctis or Toxascaris transfuga in previous studies may be Baylisascaris transfuga. The Hylobates hoolock roundworm and Pan troglodytes roundworm should be Ascaris roundworm. The present study also showed that a coevolutionary relationship may link roundworm and their corresponding hosts together.2. Cloning, expression and evaluation of the efficacy of a recombinant Baylisascaris schroederi Bs-Ag3 antigen in miceThe gene of Bs-Ag3 from Baylisascaris schroederi was amplified, cloned and sequenced. Sequence analysis indicated that the nucleotide sequences of the Bs-Ag3 from adult, L2 and L3 of B. schroederi were completely identical. A homology search performed by BLAST revealed that Bs-Ag3 shared the highest amino acid sequence identity with As37 protein from Ascaris suum (91%). The recombinant Bs-Ag3 proteins can be successfully expressed in Escherichia coli BL21 (DE3). The rBs-Ag3 was used to evaluate their ability to induce immune protective responses in BALB/c mice against L3-challenge infection in a mouse-B. schroederi model. There was a 62.91% reduction (P < 0.001) of recovery of larvae compared with that in the control group. Specific anti-Bs-Ag3 antibodies from immune protected mice had significantly higher levels of immunoglobulin G (IgG) (P < 0.0001). Our data supported the use of Bs-Ag3 as a potential candidate for vaccination against B. schroederi infection.3. Prevalence of gastrointestinal parasites among wild-trapped rhesus macaques in Sichuan province, ChinaIn the Qinghai-Tibet Plateau of China, non-human primates come into frequent contact with humans, presenting the possibility of common zoonotic parasites transmission. A cross-sectional survey was conducted to investigate the gastrointestinal parasites load of wild-trapped rhesus macaques (Macaca mulatta lasiotis) in the Sichuan province, China. Fecal samples were collected from 714 wild-trapped rhesus macaques in the National Experimental Macaque Reproduce Laboratory, mainly trapped from four local areas, namely. Jiulong, Xiaojin, Hanyuan and Beichuan. The direct smear method and the salt floatation technique were used to analyze the fecal samples. Entamoeba spp. (49.3%) and Strongyloides fulleborni (47.2%) were the most prevalent species. Other parasites detected were Trichuris trichiura (33.1%), Balantidium coli (18.5%), Oesophagostomum sp. (16.2%), Giardia duodenalis (7.4%), Enterobius sp. (1.5%), Dicrocoeliidae sp. (0.7%), Ascaris sp. (0.6%) and Bertiella sp. (0.3%). Many of these parasites are common zoonotic parasites between animals and humans. Some differences in the parasite infection rate among areas, gender and age were found with the Chi-square analysis. These data provide baseline parasitologic data for public health as well as wildlife conservation management.4. Comparison of efficacy of selamectin, ivermectin and mebendazole for the control of gastrointestinal nematodes in rhesus macaques, ChinaAn experiment was conducted to evaluate the efficacy of ivermectin and mebendazole compared with selamectin against gastrointestinal nematodes in rhesus macaques. A total of 60 rhesus macaques {Macaca mulatta), which were all infected with gastrointestinal nematodes, were randomly assigned to three treatment groups (selamectin, ivermectin and mebendazole) and one control group. Fecal samples for determining nematode egg counts were collected pre- and post-treatment. All treatments resulted in decrease in the number of eggs per gram (EPG) in the post-treatment sample compared with the pre-treatment sample. Reductions of mean egg counts from day -3 levels were 99.4% for selamectin, 99.2% for ivermectin and 99.4% for mebendazole on trial day 11, respectively. However, no significant difference was found among treatment groups. According to the data demonstrating a similar efficacy in selamectin-, ivermectin- and mebendazole-treated rhesus macaques, it was effective and convenient to apply either selamectin and ivermectin or mebendazole in rotation on the local conditions.