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Giardia duodenalis is a zoonotic parasitic protist and poses a threat to human and animal health. This study investigated the occurrence of G. duodenalis infection in post-weaned calves from Sichuan province, China. Faecal samples were collected from a total of 306 post-weaned calves (3–12 months old) from 10 farms, including 4 intensive feeding farms and 6 free-ranging farms. The overall infection rate of G. duodenalis was 41.2% (126/306) based on the PCR results at any of the three genetic loci: beta-giardin (bg), triose-phosphate isomerase (tpi) and glutamate dehydrogenase (gdh) genes. Giardia duodenalis assemblages E (n = 115, 91.3%), A (n = 3, 2.4%), and A mixed with E (n = 8, 6.3%) were identified among the 126 positive specimens. Multilocus sequence typing of G. duodenalis revealed 34 assemblage E multilocus genotypes (MLGs), 1 assemblage A MLG and 7 mixed assemblage (A and E) MLGs. The eBURST data showed a high degree of genetic diversity within assemblage E MLGs. The phylogenetic tree revealed that MLG E3 was the primary MLG subtype in Sichuan province and also the most widely distributed in China. [ABSTRACT FROM AUTHOR]

Population genetics information provides a foundation for understanding the transmission and epidemiology of parasite and, therefore, may be used to assist in the control of parasitosis. However, limited available sequence information inHeterakis gallinarumhas greatly impeded the study in this area. In this study, we first investigated the genetic variability and genetic structure ofH. gallinarum. The 1325 bp fragments of the mitochondrialCOX1gene were amplified in 56 isolates ofH. gallinarumfrom seven different geographical regions in Sichuan province, China. The 56 sequences were classified into 22 haplotypes (H1–H22). The values of haplotype diversity (0.712) and nucleotide diversity (0.00158) in Sichuan population indicate a rapid expansion occurred from a relatively small, short-term effective population in the past. The haplotype network formed a distribution around H1 in a star-like topology, and the haplotypes did not cluster according to their geographical location. Similar conclusions could be made from MP phylogenetic tree. TheFstvalue (Fst<0.16965) and AMOVA analysis revealed that no significant genetic differentiation was observed among the seven different geographical populations. Neutrality tests (Tajima's D and Fu’s Fs) and mismatch analysis indicated thatH. gallinarumexperienced a population expansion in the past. Our results indicated thatH. gallinarumexperienced a rapid population expansion in the past, and there was a low genetic diversity and an absence of population structure across the population. [ABSTRACT FROM AUTHOR]

Abstract: Ten of the 48 red pandas in the Chengdu Research Base of Giant Panda Breeding, Sichuan province, China, died in 2006 after prolonged periods of depression, weight loss, and mucocutaneous membrane xanthochromia. During postmortem examination, live heartworms were found in the right cardiac ventricles and pulmonary arteries of all 10 animals. Selamectin and ivermectin were used for clinical prophylaxis in the remaining red pandas between December 2006 and November 2010. We observed a gradual decrease in morbidity and mortality during this period. As a consequence of our prophylaxis program, dirofilariosis did not occur in the remaining red pandas at Chengdu Research Base during 2010. [Copyright &y& Elsevier]