Darren Nicholas tried to hide from police when the report was made against him, before claiming a dog had caused the injuries to his partner.
Dyfed-Powys Police received a report from a neighbouring force on March 10 that a woman had gone to hospital with a suspected broken pelvis, and disclosed that her partner had seriously hurt her.
Officers heard that the victim had managed to flee from the suspect during the assault, which had taken place five days before.
Enquiries were immediately started to find and arrest 36-year-old Nicholas, of Park View in Llanelli.
He was located the following day, and during a police interview claimed the victim had been injured when she fell over her dog.
However, thanks to further enquiries, officers were able to charge Nicholas with unlawful wounding causing grievous bodily harm.
He appeared at Swansea Crown Court on Tuesday, April 25 where he was sentenced to 15 months in prison.
He was also sentenced for a separate offence of grievous bodily harm following an unrelated incident in Llanelli, and will serve a total of 33 months.
