Back in the day, when I studied the subject, I gathered that Egypt always struggled with raising good quality cavalry because local conditions were not well suited to maintaining large herds of horses due to shortage of year-round forage. The hardier breeds of horses available locally were generally small, and better suited to hauling chariots than being ridden.  Probably why they used chariots for longer than their neighbours.

I'm sure that by the time of the revolt (and into the Ptolemaic period and later) local horse breeders were improving stocks as best they could, and increasing numbers of cavalry could be fielded. But the year-round forage problem meant they were never able to compete for numbers with rivals who could source horses from Anatolian or Iranian stock. 

@Duncan

Intresting point, i will asume for my project that Egypt did develop a cavalry but that it was still an uncommen unit to see.

By the way, could one source of horses not have been Nubia? I do not know if they had better conditions to raise horses in Nubia but it was already a place to get mercenarys and i think i have read somwere that the Nubians did develop a decent cavalry.

And my project is coming along very well and i will start building detailed army list, i will then upload them, so more expirenced wargames can tell me all the things i got wrong ;D.

If you think about the landscape of southern Egypt and northern Sudan, similar issues would arise of a shortage of year-round quality grazing land. There is certainly some, and Nubia, Kush and Meroe would extend the scope for sourcing both horses and forage. But from what I remember the horses used for their cavalry were still smaller breeds than those in use by heavy Persian cavalry. But the hardiness of the smaller breeds would give them the advantage when campaigning on Egyptian territory, whereas Persian cavalry horses might suffer.    

@DuncanWB

you see i know nothing.......call me John Snow ;)

I never thought about the landscape and suitablity for horses down there. Thanks for the informations Duncan it helps a lot. :)