Itch mite

The itch mite Sarcoptes scabiei belongs to the Phylum Arthropoda, Class Arachnida, Order Sarcoptiformes, and Family Sarcoptidae. It is a microscopic burrowing parasite.

Adult mites are roughly oval-shaped, pale in color, and measure between 0.2 and 0.45 mm. They possess short legs, with suckers on the front pairs to help them grip the host's skin.

The mite's lifecycle consists of four stages: egg, larva, nymph, and adult. The entire development process occurs within the burrows created in the host's epidermis.

Female mites create tunnel-like burrows in the stratum corneum of the skin, where they deposit eggs. A female can lay up to 50 eggs throughout her lifespan.

The rapid life cycle (approx. 10–15 days) allows the population of mites to expand quickly under favorable conditions of high animal density.

It is important to note that Sarcoptes scabiei is not a plant pest; it is an obligate parasite of mammals, causing the condition known as sarcoptic mange.

The mites cause intense irritation through their burrowing activities and the secretion of allergenic substances, leading to severe pruritus (itching) in the host.

Livestock suffer from self-inflicted trauma due to scratching, which leads to secondary bacterial skin infections, crusting, and thickening of the skin.

Infested animals show significant declines in weight, growth rates, and overall condition, resulting in direct economic losses for the farming operation.

In neglected cases, large areas of the body become hairless, and the skin may develop deep cracks, leading to systemic health problems and potentially death.

Mite prevalence peaks during colder months when livestock are housed in closer quarters, increasing the probability of direct transmission between individuals.

Humidity plays a crucial role in survival outside the host, as mites are highly sensitive to dehydration caused by dry air or direct UV exposure.

The most prominent sign is persistent scratching, particularly at night, leading to the formation of crusty lesions, hair loss (alopecia), and red papules.

Lesions typically appear first on areas with thinner hair, such as the face, ears, and abdomen, before spreading across the rest of the body.

Control focuses on the administration of acaricidal medications, such as macrocyclic lactones, administered via injection or topical application.

Effective management requires thorough cleaning and disinfection of livestock housing to eliminate mites that may persist in the environment.

All animals within a group must be treated simultaneously to ensure the eradication of the parasite and prevent re-infestation from asymptomatic carriers.

• Isolation of infected animals.
• Systemic acaricide treatments.
• Environmental sanitation of pens.
• Quarantine for new arrivals.

Long-term prevention is best achieved through good hygiene practices and regular veterinary inspections of the herd or flock.