Prevalence and Morphometric Approach for Identification of Some Paramphistome Species in Sheep Slaughtered in Maiduguri Abattoir, Borno State
INTRODUCTION
Paramphistomum cervi (Trematoda: Digenea: Paramphistomatidae), the representative species of the genus Paramphistomum, has adult flukes that inhabit the rumen and immature worms that parasitize the gallbladder and reticulum of ruminants, including cattle, sheep, goat, and some wild mammals (Xu Zhang, et al., 2014). Adult flukes parasitize the fore stomachs, causing mild disease that occasionally manifests as rumen inflammation, irregular rumination and wasting. Much more severe symptoms are caused by juvenile flukes as they migrate through the intestines and parasitize the submucosa of the duodenum, feeding on epithelial cells (Jones, 1990). This results in fetid diarrhoea, electrolyte and protein loss, generalized oedema, anorexia and, in rare cases, anaemia and emaciation of the animal (Sanabria & Romero, 2008, Sindičić, et al.., 2016). Mature Paramphistomum are also responsible for ruminitis, irregular rumination, lower nutrition conversion and loss of body condition, decrease in milk production and reduction of fertility (Mogdy et al., 2009) High prevalence of paramphistomosis occurs in tropical and subtropical regions with reports from Africa, Asia, Australia, Eastern Europe, and Russia caused by specific species of the parasites depending on the region, which include Paramphistomum cervi, Gastrothylax crumenifer, P. microbothrium, P. ichikawai, P. explanatum, P. epiclitum, Calicophoron calicophorum, Cotylophoron cotylophorum, Fischoederius elongates, and F. cobboldi (Wang et al, 2010, Surapol, et al., 2016, Khedri et al.2015). According to Nolan and crib, 2005 the vast majority of taxonomy of digenean species has been described on the basis of their adult morphology and by reference to their host and geographical distributions; P. cervi is distributed worldwide and has been reported in many countries including Nigeria (Azyaz, et al., 2013, Biu and Oluwafunmilayo., 2004). The paramphistomes are conical or cylindrical digenean with thick bodies; the most familiar species are parasites of domesticated livestock. They are distinguished from other flukes by the possession of a posteriorly located acetabulum (Mage et al., 2002).