A Revised Checklist of Cooperia Nematodes (Trichostrogyloidea), Common Parasites of Wild and Domestic Ruminants

A revision of the trichostrongylid nematode Cooperia Ransom, 1907, from deer game: recent integrative research confirms the existence of the ancient host-specific species Cooperia ventricosa (Rudolphi, 1809)

The trichostrongylid roundworms of the genus Cooperia, which are important in veterinary medicine, currently comprise 19 valid species that parasitize the small intestine of both free-living and domestic ruminants. Only four Cooperia spp. have been reported in Europe, namely C. oncophora, C. punctata, C. curticei and C. pectinata. In 2018-2022, 25 red deer (Cervus elaphus) and 30 sika deer (Cervus nippon) of both sexes and various ages from several remote locations in the Czech Republic were parasitologically examined. Intestinal nematodes of the genus Cooperia were found only in two northern regions. Using the globally recognized key book on trichostrongylid nematodes, they were preliminarily identified as C. pectinata. However, a molecular analysis of cox2 and ITS rDNA gene sequences revealed that Cooperia sp. parasitizing Czech deer is a separate taxon that is more closely related to C. oncophora than to C. pectinata. A subsequent morphological analysis and literature survey confirmed the independence of deer Cooperia sp., which is similar but not identical to bovid C. pectinata. Previous long-term correct identifications of bovid C. pectinata and misidentifications of deer Cooperia species were caused by a fundamental error in the key book mentioned above. Interestingly, the ancient trichostrongylid nematode Strongylus ventricosus from the type host red deer (Cervus elaphus) shot near Greifswald (Germany) was described by Rudolphi in 1809. Rudolphi's type material (one male and four females) was deposited in the Museum für Naturkunde (Berlin). Later, the ancient species S. ventricosus was taken as a synonym for various Cooperia spp. Our current re-examination of the type male indicated that there is a relatively good agreement with our new material from Czech deer regarding the most important characteristics of S. ventricosus (i.e., the shape and size of the male spicules); however, Rudolphi's type material is in rather poor condition. The suggested resurrection of the deer Cooperia sp. in this study as Cooperia ventricosa (Rudolphi, 1809) requires verification by collecting and analyzing new nematode material from the type locality near Greifswald.

Eukaryotic Infections in Dairy Calves: Impacts, Diagnosis, and Strategies for Prevention and Control

Eukaryotic infections are common among dairy calves and can have significant impacts on their health and growth rates. Fungal infections caused by Aspergillus fumigatus, Trichophyton verrucosum, and Candida albicans can cause respiratory diseases, dermatophytosis, and diarrhea, respectively. Protozoan parasites, including Cryptosporidium parvum, Giardia duodenalis, and Eimeria spp., are also common in dairy calves. C. parvum is highly contagious and can cause severe diarrhea and dehydration, while Giardia duodenalis can lead to poor growth and is transmissible to humans through contaminated food or water. Eimeria spp. can cause coccidiosis and lead to reduced growth rates, poor feed conversion, and death. The common helminthic infections in dairy calves include Ostertagia ostertagi, Cooperia spp., Fasciola hepatica, and Strongyloides papillosus. These parasitic infections significantly impact calf health, growth, and dairy industry productivity. Diagnosis of these infections can be made through fecal samples using microscopy or molecular methods. However, diagnosis of the infections can be challenging and requires a combination of clinical signs and laboratory tests such as culture and PCR. Preventing and controlling eukaryotic infections in dairy calves requires several measures. Good hygiene and sanitation practices, proper management strategies, and timely treatment of affected animals are important. It is also necessary to avoid overcrowding and consider vaccination against ringworm. Further research is needed to better understand the epidemiology and characterization of eukaryotic infections in dairy calves, which will help in the development of more effective prevention and control strategies. In general, good hygiene practices, appropriate management strategies, and timely treatment of affected animals are crucial in preventing and controlling the infections, ensuring the health and well-being of dairy calves.

Anthelmintic-Like Activity and Ultrastructure Changes Produced by Two Polyphenolic Combinations against Cooperia punctata Adult Worms and Infective Larvae

Cooperia punctata is one of the most prevalent gastrointestinal nematodes affecting cattle under grazing conditions, and the increasing reports of anthelmintic resistance forces researchers to look for novel control measures. Previous reports have proposed the use of polyphenolic compound (PC) combinations (Coumarin:Quercetin (CuQ) and Caffeic-acid:Rutin (CaR)) against free-living stages (L₃) of C. punctata. The objective of this study was to assess the in vitro motility inhibition of C. punctata adult worms and infective larvae using the Larval Motility Inhibition Assay (LMIA) and Adult Motility Inhibition Assay (AMIA), and to assess the structural and ultrastructural changes induced by both treatments using Scanning and Transmission Electron Microscopy. For the LMIA, infective larvae were incubated for 3 h in 0.8 mg mL^-1 and 0.84 mg mL^-1 of CuQ and CaR, respectively. For AMIA, six concentrations and five incubation periods (2, 4, 6, 12 and 24 h) were assessed using each PC combination. Cooperia punctata motility was calculated as a percentage and corrected using control motility percentages. A multiple comparisons Brown-Forsythe and Welch ANOVA test was used to compare larval motility; and to fit the dose-response in AMIA, data were analyzed with a non-linear regression four-parameter logistic equation with a variable slope, using the computer program GraphPad Prism^® V.9.2.0. Although larval motility was barely affected by both treatments (p > 0.05), adult worm motility was inhibited 100% and 86.9% after 24 h incubation with CuQ and CaR, respectively (p < 0.05). The best fit EC₅₀ for adult worm motility inhibition were 0.073 ± 0.071 mg mL^-1 and 0.051 ± 0.164 mg mL^-1 for CuQ and CaR, respectively. Main structural and ultrastructural lesions observed in both biological stages were: (i) L₃ sheath-cuticle complex disruption, (ii) collagen fibers degradation; (iii) hypodermic detachment, (iv) seam cell apoptosis and (v) mitochondrial swelling. The alterations observed suggest that the PC combinations interfere with the anatomy and physiology of the locomotive apparatus of the nematodes.