Knowsley Hall near Liverpool would very likely be a more prominent location within this document if further research was undertaken. The 13th Earl of Derby, Lord Edward Geoffrey Smith Stanley, began his collection of living animals over 20 years before the Zoological Society of London's collection was started, and at the sale of his 'Menagerie and Aviary' in 1851 it was described as the largest living zoological collection in the world.
Woolfall (1990) records that breeding potential was one of the main governing factors of the Earl's collecting policy and that single specimens of several species offered were declined on the grounds that it would be impossible to obtain a mate. Woolfall states that 191 species of mammal (192 if Red deer is split from Wapiti) lived at Knowsley between 1810 and 1851 and that 38 (39) species bred there. This total includes domestic animals such as cattle, sheep and goats which, for the purposes of this document, should be discounted. Also included is a babirusa that produced three aborted young, this should also be discounted. Inexplicably four other species that are known to have reproduced are not annotated on the Woolfall list. These are Chousingha, Red-flanked duiker, Long-nosed potoroo and Fallow deer (which must have reproduced themselves – in 1838 there were 747 of them!). It's safe to assume that even more species bred there, as specimens were often recorded as adults with a juvenile (eg. Uganda kob). In the early 19th century collecting live animals from their original homelands was a very difficult and time consuming process, therefore very young specimens at Knowsley, especially with male and female adults present, are very likely to have been born there. Some species such as Degu, Chinchilla, Coypu and various gerbils and jerboas, would also almost certainly have bred. Further research required.