Haematological alterations in Rattus norvegicus (Wistar) experimentally infected with Echinostoma paraensei (Trematoda: Echinostomatidae)

Abstract

Laboratory rats (Rattus norvegicus) were infected with Echinostoma paraensei (Trematoda: Echinostomatidae). The rodents received 150 metacercariae each and blood samples were collected weekly until the fifth week of infection. The blood samples were analyzed for determination of haematocrit, total red blood cells with their dimensions, haemoglobin and haematimetric index (mean corpuscular volume, MCV; mean corpuscular haemoglobin, MCH; and mean corpuscular haemoglobin concentration, MCHC) and platelets. Red blood cells, haematocrit and haemoglobin in the first week had significantly lower levels than those of uninfected (control) rats, suggesting the development of normocytic and normocromic anaemia with anisocytic alteration. The number of eosinophils did not increase significantly among the groups. We concluded that E. paraensei produces haematological alterations in R. norvegicus, causing regenerative anaemia. This system can therefore be a useful model to study the direct and indirect effects of gastrointestinal infections.

Haematological changes in the laboratory rat Rattus norvegicus infected with Echinostoma caproni (Trematoda: Echinostomatidae)

“…As mentioned above, the rat is a host of low compatibility with E. caproni and those rats that become infected start to expel the adult worms rapidly (Toledo et al , 2004b). This is in contrast with the data presented by Garcia et al (2012) in E. paraensei infections in rats, whose WBC values remained elevated until the end of their experiment at 5 weeks post-infection.…”

“…Although helminth infections are often related to eosinophilia (Parvathi & Kerenungikar, 2011), in the present study the level of eosinophils in peripheral blood was very low, as described previously in other echinostome infections (Huffman et al , 1986, 1988b; García et al , 2012). This is probably due to the low level of systemic immune response generated by E. caproni in the rat, together with the increased number of eosinophils at the site of infection (Hansen et al , 1991; Toledo et al , 2004b, 2006; Toledo & Fried, 2005).…”

“…In relation to intestinal helminths, it has been shown that they may induce significant reductions in RBC, HCT and HGB levels (Qadir et al , 2011). In echinostome infections, rats infected with E. paraensei showed lower RBC, HCT and HGB levels than those observed in control animals, indicating the development of normocytic and normochromic anaemia with an anisocytic alteration (Garcia et al, 2012). In hamsters infected with E. revolutum or E. caproni an increase in HGB levels was observed (Huffman et al , 1988a, b).…”

“…Variations in the levels of lymphocytes, eosinophils, basophils and monocytes are indicative of variations in the mechanisms of resistance developed by the definitive host to control the infections. However, the haematological profile has been scarcely studied in echinostome infections: E. revolutum infections in domestic chickens and golden hamsters; E. caproni (referred to as E. liei ) infections in golden hamsters; and E. paraensei infections in Wistar rats (Fried & Wilson, 1981; Huffman et al , 1986, 1988a, b; García et al , 2012).…”

Changes in Hepatic Metabolism of Rattus norvegicus Infected to Angiostrongylus cantonensis (Nematoda) and Exposed to Glyphosate-Based Herbicide

“…All animals were fed with autoclaved Nuvilab CR-1 and water ad libitum. They were maintained under controlled conditions of temperature (23 ± 2 °C) and lighting (12h photophase) [30]. At the end of each experiment, rodents were euthanized by an overdose of anesthetics, inoculated intramuscularly on the outside of the quadriceps femoris muscle, using ketamine hydrochloride (200mg/ Kg) and xylazine hydrochloride (10mg/Kg) as pre-anesthetics and sodium pentobarbital (250mg/Kg) as anesthetic.…”