Gastrointestinal strongyle nematodes (GIS) are included among the most important parasites of small ruminants. The widespread drug resistance and drug residues in products of animal origin have increased the interest in the search for natural compounds with anthelmintic activity as a valid alternative to current synthetic drugs. The aim of the present investigation was to test the ‘in vitro’ anthelmintic activity of saponins and prosapogenins from different Medicago species, selected for their importance as a forage crop worldwide for animal feeding. From these plants, saponin mixtures were extracted, purified and used at scalar concentrations to evaluate their anthelmintic activities against sheep gastrointestinal strongyles (GISs), by the egg hatch test. Treated and untreated controls were used as the comparison. Data were statistically analyzed, and EC50 and EC90 were also calculated. All saponins and prosapogenins showed inhibiting effects on GIS eggs in a concentration-dependent manner. At higher concentrations, most of them showed an efficacy comparable to the reference drug (Thiabendazole 3 µg/mL) (P < 0.001). With 1.72 mg/mL EC50 and 3.84 mg/mL EC90, saponin from M. polymorpha cultivars Anglona was the most active. Obtained results encourage further studies aimed at evaluating the efficacy ‘in vivo’ of saponins which resulted as most effective ‘in vitro’ in this study.
In sheltered dogs, the prevalence of Giardia duodenalis is frequently high and may include potential zoonotic genotypes. The prevalence, genotypes and potential risk factors of G. duodenalis were assessed in 168 dogs from four kennels (Pistoia, Prato, Florence, Valdarno) in Tuscany, central Italy and compared with data from previous Italian studies. The prevalence of other intestinal parasites was also investigated. Individual dog faecal samples collected from each kennel were examined by parasitological techniques and a rapid immunoassay for the detection of G. duodenalis and Cryptosporidium faecal antigens. On Giardia-positive samples, molecular analysis was performed for genotype identification. Overall, 69 dogs scored positive for G. duodenalis (41%), but significant differences (p ≤ 0.05) were found among the four kennels and sampling seasons. The potentially zoonotic assemblages A and B and the canine-specific assemblage C (Pistoia: A-AII, B, C; Prato: A-AII, B; Florence: A-AII; Valdarno: A and C) were identified. Toxocara canis (8.9%), Trichuris vulpis (3.6%), hookworms (1.19%) and Cryptosporidium sp. (0.6%) were also identified. The high prevalence of G. duodenalis and the identification of potentially zoonotic genotypes in all examined kennels underline the need to improve routine parasite monitoring and control measures and to provide insights into the zoonotic potential of G. duodenalis.
This study evaluated the in vitro anthelmintic activity of a liquorice (Glycyrrhiza glabra) root aqueous extract and of glycyrrhetinic acid at 30, 10, 5, 1, and 0.5 mg/mL against sheep gastrointestinal nematodes (GINs), using the egg hatch test (EHT), the larval development test (LDT), and the larval migration inhibition test (LMIT). The compounds were applied on a mixture of GIN eggs and larvae, mainly Trichostrongylus spp. and Teladorsagia/Ostertagia spp. Cytotoxicity assays were also performed. In the EHT, both candidates showed significant concentration-dependent efficacy and were significantly more effective (p < 0.001) at the highest concentrations (30 and 10 mg/mL) than the lowest ones. In the LDT, only G. glabra showed a concentration-dependent effect (R2 = 0.924), but glycyrrhetinic acid (R2 = 0.910) had significantly higher efficacy than G. glabra root extract. Moreover, the efficacy of glycyrrhetinic acid at 30, 10, and 5 mg/mL was significantly higher (p < 0.001) than at lower concentrations. In the LMIT, G. glabra showed concentration-dependent efficacy (R2 = 0.971), while considerably reduced efficacy was observed for glycyrrhetinic acid (R2 = 0.855) at the lowest concentrations. These data suggest that the two compounds may have different mechanisms of action. In the LMIT, the 50% lethal concentration (LC50) of glycyrrhetinic acid (~5.12 mg/mL) was > 2.0-fold lower when compared to G. glabra (12.25 mg/mL). Analysis and previous findings indicated low toxicity for both compounds. The results obtained encourage in vivo studies aimed at evaluating the potential use of the tested compounds as natural de-wormers in ruminants.
With the aim to find new effective natural compounds for the control of nematodes, the in vitro anthelminthic properties of purified 1% saponins showing different chemical compositions and derived from Medicago sativa (MS), Medicago arborea (MA), Medicago polymorpha cultivar ‘Santiago’ (MPS), M. polymorpha cultivar ‘Anglona’ (MPA), and 1% prosapogenins from M. sativa (MSp), were evaluated and compared. As a source of nematode eggs, pooled fresh fecal samples taken from dairy donkeys naturally infected by gastrointestinal nematodes were used. From fecal samples, eggs were recovered, suspended in deionized water, and used immediately in the bioassay (egg hatch test). The activity of the tested compounds was compared to positive (0.1% thiabendazole) and negative (deionized water and 1% DMSO) controls. All experiments were repeated in triplicate and the obtained data were statistically analyzed. All the tested plant compounds caused a significant (p < 0.05) inhibition of nematode egg hatching (>80%). Moreover, all saponins and prosapogenins showed in vitro anthelmintic properties statistically comparable to that of the reference drug (p < 0.05), except for MPS extract. Obtained results showed that the different Medicago saponins evaluated in this study possess high anthelmintic properties against gastrointestinal nematodes of dairy donkeys, although to a different extent depending on their composition.
Aelurostrongylus abstrusus is considered the most important respiratory nematode of domestic cats worldwide. This parasite inhabits the alveoli, alveolar ducts, and bronchioles and causes a subacute to chronic respiratory clinical disease. Clinical signs may occur in domestic cats of any age, though they are more often described in young animals. Physical examination, echocardiography, thoracic radiography, pulmonary and cardiac pathological findings, classical, and molecular parasitological analysis of a six-month-old kitten referred at the Veterinary Teaching Hospital of the University of Pisa (Italy) led to a diagnosis of parasitic bronchopneumonia caused by A. abstrusus, which was complicated by severe pulmonary hypertension (PH) and right-sided congestive heart failure (R-CHF) that caused the death of the animal. Cases of reversible PH associated with A. abstrusus infection have been seldom reported in cats. This is the first report of fatal PH and R-CHF in a kitten with clinical aelurostrongylosis.
1 April 2020 in International Journal for Parasitology: Parasites and Wildlife
Italy is the only European country where the crested porcupine (Hystrix cristata) lives. A parasitological investigation was performed on faecal samples, aimed to evaluate Giardia and other parasites in a free-ranging crested porcupine population in Central Italy. Samples were collected from captured and road-killed individuals as well as from feeding areas and pathways. Collected faecal samples were examined by the Mini-FLOTAC technique and a rapid immunoassay for the search of Giardia and Cryptosporidium spp. faecal antigens. For the identification of Giardia species and genotypes, molecular analysis was performed on Giardia-positive samples, by using PCR protocols able to amplify glutamate dehydrogenase, triosephosphate isomerase and a fragment of the small subunit ribosomal RNA genes. A total of 52 crested porcupine faecal samples were collected and analysed. At microscopical examination, 39 out of 52 samples were found positive for at least a single parasite species and six different parasite taxa were identified. Forty-eight percent (25/52) of faecal samples were positive for Giardia spp. and 1.9% (1/52) for Cryptosporidium spp. at the immunoassay. Among 12 faecal samples belonging to different individuals, 33.3% (4/12) were positive for Giardia spp. By using the Mini-FLOTAC technique, positivity for Trichuris spp. (32.7%, 17/52), gastrointestinal strongyles (32.7%, 17/52), capillariid eggs (3.8%, 2/52) and coccidian oocysts (1.9%; 1/52) was also evidenced. Molecular analysis was performed on 17 out of 25 Giardia-positive isolates. At the SSU rDNA locus, expected bands were achieved for 12 out of 17 isolates and all samples were assigned to Giardia duodenalis assemblage B. Sequencing at tpi locus revealed potentially zoonotic G. duodenalis assemblage AII (two isolates) and assemblage BIV (one isolate). The present study provides the first report of G. duodenalis infection in H. cristata. More in depth studies are needed on the impact and epidemiology of G. duodenalis and other identified parasites in crested porcupines.