Parasites pose a significant challenge to dairy herd health management in Kenya. They reduce productivity, cause disease, and increase veterinary costs, making parasite control a vital component of routine on-farm management practices. Understanding the types of parasites that affect dairy cattle and the methods available to control them supports sustainable dairy production and animal welfare. This chapter explores the classification of parasites affecting dairy herds and the practical strategies for managing them effectively on Kenyan dairy farms.

3.1 Types of Parasites

In Kenyan dairy farming, parasites are broadly categorized into external and internal parasites based on where they live on or in the animal. Each group causes distinct health problems and requires specific control measures. Identifying the type of parasite involved is essential for targeted intervention that minimizes economic losses and improves animal well-being.

3.1.1 External Parasites

External parasites live on the surface of the dairy cow’s body, feeding on blood, skin, or secretions. These parasites cause irritation, skin damage, and can be vectors for other diseases.

Common External Parasites Affecting Dairy Cattle in Kenya

• Ticks: Ticks are widespread in Kenya, especially in the warmer regions, and are notorious for transmitting diseases like East Coast Fever and babesiosis. They attach firmly to the skin, feeding on blood and causing anemia and skin lesions.
• Lice: Both biting and sucking lice infest dairy cattle, leading to intense itching, hair loss, and reduced milk yield due to stress and discomfort.
• Mites: Mites cause mange, a skin disease characterized by scabs, hair loss, and thickened skin. Mange decreases the animal's resistance to other infections.
• Flies: Biting flies such as stable flies and tsetse flies irritate cattle and transmit diseases like trypanosomiasis, which is a major constraint in parts of western Kenya.
• Fleas: Although less common, fleas can infest dairy cattle, particularly in poorly managed housing, causing irritation and secondary infections.

External parasites are often visible during routine inspections and can cause behavioral changes such as excessive scratching or restlessness, which alert the farmer to their presence.

3.1.2 Internal Parasites

Internal parasites inhabit the digestive tract, lungs, or other organs of the dairy cow, impairing nutrient absorption, causing organ damage, and reducing overall health.

Major Internal Parasites in Kenyan Dairy Herds

• Gastrointestinal Nematodes: These roundworms infest the stomach and intestines, leading to poor feed conversion, weight loss, diarrhea, and in severe cases, death. Common species include Haemonchus contortus and Ostertagia ostertagi.
• Liver Flukes: The liver fluke Fasciola hepatica damages the liver and bile ducts, causing anemia, reduced milk production, and susceptibility to bacterial infections. Flukes thrive in wet, marshy areas found in some Kenyan highlands.
• Lungworms: Lungworms cause respiratory distress, coughing, and reduced exercise tolerance, which negatively affect dairy cattle performance.
• Coccidia: These protozoan parasites infect the intestines, particularly in young calves, causing diarrhea and poor growth.
• Tapeworms: Tapeworms inhabit the intestines and may cause mild weight loss and digestive disturbances.

Internal parasites often remain undetected until clinical signs such as weight loss, decreased milk yield, or poor growth appear, necessitating routine fecal examinations and herd health monitoring.

Chapter Summary

This chapter covers the essential routine management practices vital for maintaining a healthy dairy herd. It begins by distinguishing between external and internal parasites, emphasizing their impact on animal health. Various parasite control methods are explored, including chemical treatments, biological controls, and integrated approaches that combine both strategies. The importance of adhering to vaccination schedules is highlighted to prevent common diseases. Proper hoof care is discussed as a critical practice to maintain mobility and prevent infections. The chapter then examines disbudding methods, focusing on the use of hot iron and chemical agents like caustic soda. Dehorning procedures are detailed with explanations of tools such as dehorning wire, saws, and cauterization techniques. Finally, the chapter underscores the significance of grooming and the use of appropriate personal protective equipment, tools, and equipment to ensure effective herd health management.