The purpose of the present study was to describe the normal ultrasonographic characteristics of the udder and teats in lactating Jennies. Seven lactating Baladi Egyptian Jennies were examined ultrasonographically using 6-8 MHz linear probe. Sagittal and transverse scans of the udder parenchyma and teats were performed for right and left halves through direct (transcutaneous) and indirect (modified stand-off pad) techniques. Measurements of the TCL (teat canal length), TCD (teat canal diameter), TWT (teat wall thickness) and TCD (teat cistern diameter) of both right and left teats were compared for significant difference. The udder parenchyma was identified as coarse granular hypoechoic structure with multiple anechoic cavities. The teat has 3 distinct layers; the outer hyperechoic skin, the inner hyperechoic mucosa and the hypoechoic muscle layers. No significant differences were observed between measurements of the right and the left side. In conclusion, ultrasonography is a safe, effective and non-invasive method that allowed the visualization of the mammary gland (parenchyma and teat) in donkeys. Alteration from the normal ultrasonographic appearance could be helpful for diagnosing pathological conditions of the udder and teats.

Key words: Donkey, Mammary gland, Teat, Udder, Ultrasonography