I think you must be referring to Lord Stanley, the Earl of Derby, who bred various equid hybrids in his private menagerie at Knowsley.
A photograph of a Knowsley born mountain zebra x Asiatic wild ass (I think a kiang) hybrid, mounted in the British Museum (Natural History), is reproduced in the book “The Horse and its Relatives” (Lydekker, 1912).
I only know the Catskill animals came from an expedition to Eritrea (in 1930?) and the captors divided the asses into two groups: Somali and Nubian. I thought the Catskill zoo took both. But i am glad the Nubians survived.
I think the expedition was in 1937; it was descendants of these animals that Catskill received from Munich Zoo.
I saw the so-called Nubian wild asses on my only visit to Catskill back in 1984. I know that their purity is in doubt but they looked right; they differed from Somali wild asses in lacking leg stripes and having a distinctive cross on the shoulder.
Thank you very much; it was indeed the Earl of Derby. I saw the booklet of mylord's equine collection with the colour pictures in the library of the Amsterdam Zoo. Yep, i have even read the Tegetmeier book at the time. And I saw photos of an awful lot of Professor Ewart's experiments in an old book on genetics. (It was a pity Ewart conducted his experiments just before the birth of modern genetics with Mendel.) However, the first recorded birth of a zebroid was in Turin, Piemont being annexed to France at the time.. I think it was stillborn but drawings were made of it.. The most prestigious hybrids were bred by professor Antonius in the Vienna Zoo. A lot of photos appeared in the Zoo magazines between the wars. (The same chap who studied the last Syrian Onager, presented by Turkey to the Emperor.) Antonius bred every hybrid he could arrange for! Oh, i forget i received a believable story of a female zebra-horse hybrid who produced one foal with a horse. Since fertile mules and a fertile hinny have been proved it is not that farfetched..
Re. the equine hybrids in Vienna. Antonius arranged for several crossings. Photos appeared in "Der Zoologische Garten" i think; i have seen them all. In particular i vividly remember a hybrid between a (Persian?) Onager stallion and a Hartmann's Zebra mare. The foal died young as with most of Antonius experiments..
Re. the fertile zebroid and her foal. Photographs have been taken but i did not manage to obtain these. I only have the account of a woman who knew about these hybrids and saw them. The foal indeed reached maturity.
I will try to provide the link. But I am not good at this.
The lady reacted on an article about a mammut hybrid.
file:///C:/Users/user/Downloads/Michigan%20Farmer%20Unearths%20Bones%20of%20Rare%20Mammoth%20Hybrid%20From%20Nearly%2015,000%20Years%20Ago%20-%20Yahoo.html
Genetics are not unfamiliar to me. As i wrote a paper on "The Heredity of Coat Colour in Donkeys and Mules" and have been in touch with scientists who were working on fertile mules and hinnies. It is excessively rare.
PS. If the link does not work i will type the whole story...
Re. the equine hybrids in Vienna. Antonius arranged for several crossings. Photos appeared in "Der Zoologische Garten" i think; i have seen them all. In particular i vividly remember a hybrid between a (Persian?) Onager stallion and a Hartmann's Zebra mare. The foal died young as with most of Antonius experiments..
Re. the fertile zebroid and her foal. Photographs have been taken but i did not manage to obtain these. I only have the account of a woman who knew about these hybrids and saw them. The foal indeed reached maturity....
An alleged horse x (zebra x donkey) hybrid was born at London Zoo.
In the posthumous publication “Life Among Wild Beasts in the Zoo” (1900) Abraham Bartlett describes this specimen as a "remarkable double mule" - having in its composition zebra, horse and ass.
Charles Darwin was fascinated by this animal and records seeing this “curious triple hybrid” which was born to a bay mare after mating with a zebra x ass hybrid.
I certainly hope you have been able to find the lady's story on the fertile zebra-horse hybrid in the comments of the mammut story.
I am aware of the triple hybrid story but as it involves a MALE hybrid i do not believe it to be true. I firmly believe in evolution but am NOT a darwinist. With all due respect to Darwin i do not believe he was infallible and reject the quasi-divine status the darwinists gave him.
There are rumors of fertile zebroids but the lady's story is the only one i found.
More hybrids: In the wild Grevy's Zebra stallions mate with Plains Zebra mares who sometimes produce offspring. A FEMALE hybrid appeared to be fertile and gave birth to a foal. Let us hope she did not adopt a waif. The article with photos is available and I even put the scans on Facebook as well as my Pinterest page https://nl.pinterest.com/jehanbosch/zebroid/
A Californian zoo also had a Grevy Zebra stallion and a Plains Zebra mare and they got three female and one male hybrids. The female foals reached maturity but no report on offspring so there was not any..
