Jenny-ass

c. 1849, G. Herbert Rodwell, Old London Bridge, London: Henry Lea, Chapter 15, p. 158, […] this little donkey could not be trusted in the road, for it was always getting under the wheels, because it would not let its mother, a fine fat old jenny ass in the shafts, alone.

Source: wiktionary

But a man who holds so tightly to what he calls his rights over what he calls his debts will hold tightly also to what he calls his rights over her whom he calls his wife. No sir smile neighbour shall covet his ox or his wife or his manservant or his maidservant or his jackass. / —Or his jennyass, Buck Mulligan antiphoned.

Source: wiktionary

[…] old rope is for tethering your jennyass […]

Source: wiktionary