How can ear mites be identified in a calf? - briefly
Ear mite infestation is diagnosed by visual inspection of the ear canal for dark, crusty debris and by collecting ear swabs for microscopic identification of the mites. Otoscopic examination may reveal live parasites attached to the canal walls.
How can ear mites be identified in a calf? - in detail
Ear mite infestation in young cattle presents with distinct clinical signs and can be confirmed through a series of practical examinations.
Typical observations include intense scratching of the ears, head shaking, and a noticeable accumulation of dark, waxy debris in the external auditory canal. The debris often contains visible, motile organisms that resemble tiny white or yellowish specks. In advanced cases, the skin of the ear canal may appear inflamed, thickened, or ulcerated, and secondary bacterial infections can develop, producing a foul odor.
Diagnostic procedures follow a stepwise approach:
- Visual inspection – Gently separate the pinna and examine the canal with a bright light. Look for live mites, eggs, or characteristic crusts.
- Otoscopic examination – Insert a veterinary otoscope to assess the depth of infestation and evaluate the condition of the tympanic membrane. This method provides magnification and illumination, facilitating detection of mites attached to the canal walls.
- Ear swab or canal scraping – Collect material using a sterile cotton swab or a small curette. Transfer the sample onto a glass slide.
- Microscopic analysis – Examine the slide under a low‑power microscope (10–40×). Identify adult mites, nymphs, larvae, or eggs based on their elongated bodies, four pairs of legs (adults), and distinct segmentation.
- Laboratory confirmation – In ambiguous cases, submit the sample for polymerase chain reaction (PCR) testing to detect Otodectes cynotis DNA, ensuring species‑specific identification.
A positive finding of mites or their developmental stages confirms the diagnosis. Absence of visible parasites does not exclude infestation; repeated sampling or deeper canal scraping may be necessary when clinical signs persist. Prompt identification enables targeted acaricidal treatment, reducing discomfort and preventing spread within the herd.