Histological Impact of Intestinal Helminth Parasites of some Vertebrates sold in Select Markets, Rivers State, Nigeria

Abstract

Intestinal helminth parasites' impact on the health of their hosts in several ways, including altering the structure and function of host tissues. Histological impacts of three helminthes from three vertebrate hosts are hereby reported. Intestinal helminth community of greater cane rats (Thryonomys swinderianus) of Omagwa Bush Meat Market, Rivers State, Nigeria, was sampled to compare with previous reports. Intestinal tracts of T. swinderianus (n=12) samples were obtained from the slaughterhouse at Omagwa Bush Meat Market. Fish specimens (Bostrychus africanus [n=24] and Periophthalmus papilio [n=17]) were obtained from fishers at Creek Road Market, Rivers State. Sampling lasted from June to August 2023. All hosts were examined for parasites by dissection and microscopic examination; histologic impacts were assessed using Hematoxylin and Eosin staining procedures. Hosts and parasites were appropriately identified using keys. Thryonomys swinderianus were infected by nematodes- Trichuris sp. (16.7%), Oesophagostomum venulosum (50%) and Strongylus sp. (25%). Raphidascaroides africanus (20.8%) and Neoechinorhynchus sp. (6%) infected Bostrychus africanus and Periophthalmus papilio, respectively. Histologic impacts observed were as follows: T. swinderianus infected with Trichuris sp. showed mild disintegration of tissues. Raphidascaroides africanus caused detachment of the connective tissue core and dispersed mucus-secreting cells in B. africanus; Neoechinorhynchus sp. resulted in loss of secretory cells associated with disruption of the intestinal epithelial lining in P. papilio. The study showed that parasites result in histological changes, including tissue disintegration and dispersal/loss of secretory cells, in vertebrate hosts, and helminths of T. swinderianus include Trichuris sp., Oesophagostomum venulosum and Strongylus sp.