# Parasitic infections in the organic beef cattle herds of southern Poland during the grazing season, with the first record of Calicophoron daubneyi (Dinnik, 1962) in the country

## TL;DR

This study reports on parasitic infections in organic beef cattle in southern Poland and identifies a new parasite species, Calicophoron daubneyi, for the first time in the country.

## Contribution

The first documented occurrence of Calicophoron daubneyi in Poland and detailed infection patterns in organic cattle herds.

## Key findings

- Eimeria infections were most prevalent in calves, with E. bovis and E. zuernii being the main species.
- Nematode infections were dominated by Haemonchus placei, particularly in first-time grazing yearlings.
- Calicophoron daubneyi was identified in one herd through morphological and molecular analysis.

## Abstract

Grazing cattle are vulnerable to the harmful effects of gastrointestinal parasites. Organically farmed cattle are even more so because conventional antiparasitic treatments are restricted, yet parasite infection patterns in Polish organic herds remain poorly documented.

Imported beef cattle were studied during the pasture season in four organic herds in southern Poland. The McMaster quantitative flotation method was used to estimate infection prevalence (P, %) coproscopically and to quantify intensities of coccidia oocyst output (Ic, OPG) and nematode egg output (In, EPG) per gram of faeces. The qualitative sedimentation method was applied to assess the presence of digenean eggs. Coccidial species of the Eimeria genus were identified by sporulation, and nematodes of the Strongylida order by larvoscopy. Digenean Paramphistomatidae were identified by morphological examination of adult fluke specimens obtained at slaughter from a sick heifer in one of the studied herds and by molecular analysis of the flukes’ internal transcribed spacer 2 ribosomal DNA.

The prevalence of Eimeria infection was P = 28.9 (23.8–34.5)%, and the mean Ic was 287 (113–793) OPG. Calves were most heavily infected, mainly with E. bovis and E. zuernii. The prevalence of nematode infections reached P = 46.0 (40.2–51.5)%, and the mean In was 113 (88–147) EPG. Haemonchus placei dominated over Ostertagia sp. and Trichostrongylus axei, and the most infected were first-time grazing yearlings. Paramphistome eggs were confirmed in only one herd. Morphological and PCR analysis of the adult rumen flukes revealed the presence of Calicophoron daubneyi (Dinnik, 1962) in this herd.

This is the first Polish evidence of C. daubneyi, and it heralds an enhanced surveillance need regarding this highly pathogenic digenean.