"Seo an t-ugh."
Translation:This is the egg.
I think in Irish it varies by dialect, FGB notes the variable masculine version (Var:m, gs. uibh) and the Cork Irish dictionary from the corkirish blog gives only masculine, and the Dineen dictionary (also Munster Irish) gives masculine and feminine.
On the other hand, An Ghaeilge by A. Doyle and E. Gussmann, Polish textbook for Munster Irish, gives only feminine gender for ubh, so perhaps the masculine variant dies (or died) out and is just archaic.