Thirty-seven-year-old Shawanna Hughes, of Oyster Bay, failed to get proper treatment for the injury suffered by her pit bull mix, Snowball.
The dog eventually had to have one of its legs amputated.
"This defendant left this serious injury untreated for weeks, causing pain and severe disfigurement to a defenseless animal," District Attorney Kathleen Rice said in a news release.
In addition to the jail sentence, Hughes is not allowed to own any animals for five years. Snowball has since been adopted.
Hughes also has a pending felony abuse case over another pit bull puppy whose leg was improperly amputated.
A veterinary aide also was charged in that case.