Seroprevalence of Major Pasture-Borne Parasitoses (Gastrointestinal Nematodes, Liver Flukes and Lungworms) in German Dairy Cattle Herds, Association with Management Factors and Impact on Production Parameters

Abstract

Pasture-borne parasites adversely affect bovine health and productivity worldwide. In Europe, gastrointestinal nematodes, especially Ostertagia ostertagi, the liver fluke Fasciola hepatica and the lungworm Dictyocaulus viviparus represent the most important parasites of dairy cattle. The present study assessed exposure towards these parasites among 646 cattle herds in three parts of Germany during 2017–2019 via antibody detection in bulk tank milk (BTM). Overall, O. ostertagi levels indicative of production losses were detected in 41.2% (266/646; 95% confidence interval (CI): 37.4–45.1%) of BTM samples, while F. hepatica seroprevalence amounted to 14.9% (96/646; 95% CI: 12.2–17.9%). Only 2.3% (15/646; 95% CI: 1.4–3.9%) of samples were D. viviparus antibody-positive. Significantly lower O. ostertagi as well as F. hepatica seroprevalence was detected in dual-purpose breeds compared to high-performance breeds from the same region. Management factors related to parasite exposure included access to fresh grass and hay, silage quality and anthelmintic treatment. Furthermore, F. hepatica and O. ostertagi seropositivity was significantly associated with suboptimal herd-level body condition. Interestingly, the relationship between seropositivity and productivity differed between breed types. Negative impacts on milk yield were detected only in high-performance breeds, while O. ostertagi seropositivity was associated with a lower milk fat content in dual-purpose herds.

Rumen (Calicophoron/Paramphistomum spp.) and Liver Flukes (Fasciola hepatica) in Cattle—Prevalence, Distribution, and Impact of Management Factors in Germany

“…Although seroprevalence values are difficult to compare with the prevalence determined in our investigation, as the sensitivity differs and only patent infections can be detected by coproscopy [ 13 , 35 ], the most recent seroprevalence study confirms higher exposure to liver flukes in the south than in the north of Germany [ 28 ]. However, F. hepatica BTM seroprevalence in the region “East” was only 1% [ 28 ] compared to nearly 8% patent infections in our study. This may be explained by different sample sets (BTM samples were collected in 2017–2019, faecal samples in 2018–2020, and participating farms overlapped only partially), but needs to be clarified in future studies.…”

“…In a bulk tank milk (BTM) study conducted in 2008, seroprevalences amounted to 9-19% in the German federal states included in the region "West" [27], but this region was not included in a recent BTM study on fasciolosis in Germany examining samples from 2017 to 2019 [28]. Although seroprevalence values are difficult to compare with the prevalence determined in our investigation, as the sensitivity differs and only patent infections can be detected by coproscopy [13,35], the most recent seroprevalence study confirms higher exposure to liver flukes in the south than in the north of Germany [28]. However, F. hepatica BTM seroprevalence in the region "East" was only 1% [28] compared to nearly 8% patent infections in our study.…”

“…Based on recent findings of C. daubneyi in German cattle herds, it can be assumed that the parasitosis is also spreading in this country [ 26 ]. For the liver fluke Fasciola hepatica , a seroprevalence of 15% was most recently reported for Germany, and the risk of infection was associated, among other factors, with grazing and feeding fresh grass [ 27 , 28 ]. Due to the same intermediate host, on all farms with liver fluke infection, cattle can potentially also get infected with C. daubneyi .…”

A machine learning approach using partitioning around medoids clustering and random forest classification to model groups of farms in regard to production parameters and bulk tank milk antibody status of two major internal parasites in dairy cows

“…ostertagi antibody status and milk production and quality parameters [ 51 – 53 ]. Interestingly, in their recent study which in large parts was based on the data set collected in the underlying three years cross–sectional study throughout Germany, Springer et al [ 22 ] identified a negative impact on milk production level only in high–performance dairy breeds while lower milk fat content was observed in dual–purpose herds positive for O . ostertagi .…”

“…ostertagi on farm level was assessed by BTM antibodies determined with the IDEXX Fasciolosis Verification Test (IDEXX GmbH) and the Svanovir O . ostertagi –Ab ELISA (Boehringer Ingelheim) in a previous study [ 22 ]. As in the previous study and in accordance with the manufacturer’s recommendation, F .…”