The Genome Sequence of the Anthelmintic-Susceptible New Zealand Haemonchus contortus

Abstract

Internal parasitic nematodes are a global animal health issue causing drastic losses in livestock. Here, we report a H. contortus representative draft genome to serve as a genetic resource to the scientific community and support future experimental research of molecular mechanisms in related parasites. A de novo hybrid assembly was generated from PCR-free whole genome sequence data, resulting in a chromosome-level assembly that is 465 Mb in size encoding 22,341 genes. The genome sequence presented here is consistent with the genome architecture of the existing Haemonchus species and is a valuable resource for future studies regarding population genetic structures of parasitic nematodes. Additionally, comparative pan-genomics with other species of economically important parasitic nematodes have revealed highly open genomes and strong collinearities within the phylum Nematoda.

Keywords: Haemonchus contortus; anthelmintic-susceptible; genome; helminth; parasite.

Fig. 1.

—(A–D) Scanning electron micrographs of adult male Haemonchus contortus NZ_Hco_NP. (A) Entire adult male; (B) mouth or anterior end (head) showing the tooth/lancet of buccal cavity (arrow), (C) tail or posterior end showing the bursal rays; and (D) tip of spicule showing the barb at distal end (arrow). (E and F) Circos plots showing the syntenic relationships between the six chromosomes of H. contortus NZ_Hco_NP with Caenorhabditis elegans N2 (E) and H. contortus HCON_V4 (F). Each colored line crossing the circle represents a unique alignment with chromosomes ordered to maximize collinearity among the genomes. (G) Venn diagram showing the distribution of shared gene families among the major related genomes of the phylum Nematoda. All H. contortus NZ_Hco_NP scaffolds with at least five one-to-one orthologs shared between the two species were compared.