The Hidden War on Sheep Farms

Winning Against Parasites in Ethiopia

In the highlands of Ethiopia, a quiet revolution is underway to protect sheep from invisible enemies that have plagued farmers for generations.

Sheep are the backbone of rural livelihoods in Ethiopia, contributing up to 63% of all monetary income for many smallholder farmers4 . However, for years, gastrointestinal parasites have silently undermined this crucial resource, causing substantial economic losses through reduced productivity, poor growth, and sometimes death1 .

Recognizing this challenge, researchers and communities have joined forces to implement strategic parasite control programs that are transforming sheep farming across the country.

63%

of income from sheep for smallholder farmers

54.4%

of sheep infected before intervention

The Invisible Enemy: Understanding Gastrointestinal Parasites

Gastrointestinal parasites represent one of the most significant health constraints for sheep production in Ethiopia. These microscopic invaders include various worms and flukes that inhabit the digestive system of animals, competing for nutrients and damaging tissues.

The most common culprits identified in Ethiopian sheep include Strongylid worms (30.4%) and Fasciola liver flukes (18.2%), though many other species contribute to the problem1 . These parasites thrive in Ethiopia's diverse agro-ecological zones, with wet mid-highland environments creating particularly favorable conditions. Research shows that animals living in these wet regions are 23 times more likely to harbor strongylid infections compared to those in moist highland areas1 .

Economic Impact of Parasites
  • Reduced weight gain Negative
  • Lower reproduction rates Negative
  • Poor wool quality Negative
  • Decreased milk production Negative

A Strategic Approach: The Community-Based Breeding Program

To address this challenge, the International Livestock Research Institute (ILRI) in Ethiopia launched an integrated animal health intervention in 2018. This program combines improved management practices, enhanced nutrition, and strategic use of anthelmintic dewormers across community-based breeding sites in multiple regions1 .

The approach marked a significant shift from haphazard treatment to carefully timed interventions. Rather than waiting for animals to show signs of sickness, the program implemented preventive deworming twice a year - at the beginning of the long and short rainy seasons when parasite populations typically surge1 .

"Before community-based breeding programs, we valued sheep by number, not by quality. Breeding was random; we let any ram mate with any ewe. We accepted what came. But with training, we learned the value of selective breeding"

Farmer Ayelech from Bonga6

2x

Income increase for farmers

2

Deworming cycles per year

2018

Program launch year

Inside the Groundbreaking 2018-2021 Parasite Control Study

Between 2018 and 2021, researchers conducted a comprehensive assessment of worm burden and control strategies across nine villages in three districts of Ethiopia. The study provides compelling evidence for the effectiveness of strategic parasite management1 .

Methodology: Tracking the Invisible

The research team examined a total of 1,928 sheep before treatment and 735 sheep after deworming, collecting fecal samples directly from the rectum of each animal1 .

Table 1: Prevalence of Gastrointestinal Parasites Before and After Intervention
Parasite Type Pre-Treatment Prevalence Key Findings
Strongylid 30.4% Most frequently identified parasite
Fasciola 18.2% Primary liver fluke species
Any GIT Parasites 54.4% Over half of sheep infected before intervention

Data source: 1

Remarkable Results: Turning the Tide on Parasites

The findings demonstrated a dramatic impact of strategic parasite control:

Table 2: Impact on Infection Severity After Strategic Deworming
Infection Level Egg Count (EPG) Outcome After Intervention
Mild < 500 Persisted at low levels
Moderate 500-1,500 Reduced by one third
High > 1,500 Completely eliminated

Data source: 1

Impact on Farmer Income

"We earn two to three times more than before," says farmer Ayelech, who used her increased income to replace her grass-thatched house with a sturdier home and better support her son's education6 .

The Scientist's Toolkit: Essential Resources for Parasite Research

Understanding and combating sheep parasites requires specialized tools and techniques. Here are the key components of the parasitologist's toolkit:

McMaster Technique

Quantifies parasite eggs per gram of feces to measure infection intensity and treatment efficacy1 .

FAMACHA© Score

Assesses anemia levels through eye membrane color to help target treatment to animals needing it most1 .

Fecal Egg Count Reduction Test (FECRT)

Calculates percentage reduction in egg counts after treatment to monitor anthelmintic drug effectiveness and resistance1 .

Flotation and Sedimentation Methods

Separates and identifies parasite eggs from fecal matter to determine which parasite species are present1 .

The Resistance Challenge: An Emerging Threat

Despite the promising results, researchers identified concerning signs of emerging drug resistance in some parasite populations1 . This finding aligns with broader trends across Ethiopia, where studies confirm that gastrointestinal nematodes in sheep are developing resistance to multiple anthelmintics8 .

Drug Resistance in Bishoftu, Central Ethiopia

One recent study revealed widespread resistance to ivermectin, albendazole, and tetramisole, with fecal egg count reduction rates below the 95% efficacy threshold8 .

Recommended Strategies to Combat Resistance:
  • Regular monitoring of drug efficacy using FECRT
  • Targeted selective treatment of only heavily infected animals
  • Integration of non-chemical approaches like pasture rotation
  • Combination treatments using multiple drug classes

Beyond Treatment: The Power of Integrated Management

The most successful parasite control programs recognize that medication alone isn't the solution. Instead, they integrate strategic deworming with improved overall management practices.

Selective Breeding

Through participation in the community-based breeding program, farmers learned selective breeding techniques that improved herd genetics and resilience.

Enhanced Nutrition

Better feeding practices strengthened sheep immune systems, making them more resistant to parasite infections.

Improved Marketing

Farmers gained access to better markets, with sales reaching major towns and even the capital, Addis Ababa6 .

Women's Leadership

The integration of women in leadership roles helped disseminate improved genetics and health practices throughout communities6 .

The Road Ahead: Sustainable Solutions for Ethiopian Sheep Farmers

The battle against gastrointestinal parasites in Ethiopian sheep is far from over, but the strategic approaches implemented through community-based programs offer a promising path forward. The remarkable achievement of eliminating high-burden infections through twice-yearly deworming demonstrates the power of simple, consistent interventions1 .

Future Challenges
  • Preserving drug efficacy
  • Expanding programs to more regions
  • Ongoing monitoring and farmer education
  • Research into alternative control methods
Future Opportunities
  • Improved rural economic growth
  • Enhanced food security
  • Youth employment in agriculture
  • Scalable model for other regions

"Bonga sheep are not just our pride, they can be all of Ethiopia's pride as well. Our youth can build a future here, escaping the risks of poverty or unemployment"6 .

References