Diagnosis and monitoring of anthelmintic resistant gastro-intestinal nematodes of UK cattle (MSc)

Parasitic nematodes negatively impact on animal welfare and cost the cattle industry millions of pounds each year in lost production and treatment costs. The emergence of anthelmintic resistant nematodes will only increase this problem as infections will be more difficult to control. 

The aim of this study was to develop a better understanding of what farmers do to control parasitic nematodes on UK cattle farms, and evaluate the use of faecal egg counts (FEC) in conjunction with quantitative real-time PCR (qPCR) to assess the level and nature of an infection.

Surveys were conducted of cattle farmers in South West England, regarding their cattle management practices. This revealed a number of farmers are still managing their land and animals in a way known to promote the development of anthelmintic resistance (AR) and increase the risk of clinical O. ostertagi and C. oncophora infections, including the use of anthelmintics in an unsustainable manner.

A qPCR was developed to quantify the amount of Cooperia and Ostertagia in a mixed sample of L1 (stage 1) larvae, indicating the proportion of each species present. FEC and qPCR were performed on faecal samples from 16 farms, to measure the level of the infection (eggs per gram of faeces) and the ratio of Ostertagia to Cooperia. No link was found between the level of infection and ratio of species present. By using FEC and qPCR together, infections can be more accurately monitored at both herd and individual level. Response to anthelmintic treatment can also be assessed and used to indicate the development or presence of AR in nematodes. 

More work needs to be undertaken to educate farmers about better land and animal management, as this will reduce dependence on anthelmintics and delay the development of AR.

The Project

The aims and objectives of this project are:

• To develop a quantitative PCR (qPCR) capable of distinguishing between the predominant gastro-intestinal nematode worms affecting UK cattle, Cooperia oncophora and Ostertagia ostertagi, in a sample of stage 1 (L1) larvae
• To gather survey data indicating current trends in gastro-intestinal parasites control in cattle.

Student

Charlotte Florence