Sentinel Capital Partners acquired Livonia, Mich.-based Pet Supplies Plus for an undisclosed sum.

The private equity firm said Pet Supplies is the largest independent pet-specialty operator in the U.S., with 448 stores across 33 states. The seller was private equity firm Irving Place Capital, which acquired Pet Supplies in 2010, according to S&P Global Market Intelligence data.

Sentinel Capital invests in U.S. and and Canadian lower middle-market companies in the aerospace and defense, business services, consumer, distribution, food and restaurants, franchising, healthcare and industrial sectors.