OBJECTIVE: We hypothesized that cold ischemia during partial orchiectomy would lead to higher serum testosterone levels and preservation of testicular architecture than warm ischemia in a prepubescent rat model. MATERIALS AND METHODS: Eighteen prepubescent male Sprague-Dawley rats were randomized to three different surgical groups: sham surgery, bilateral partial orchiectomy with 30 min of cord compression with cold ischemia, or bilateral partial orchiectomy with 30 min of cord compression with warm ischemia. Animals were killed at puberty, and serum, sperm, and testicles were collected. Histological tissue injury was graded by standardized methodology. RESULTS: Mean serum testosterone levels were 1445 ± 590 pg/mL for the sham group, 449 ± 268 pg/mL for the cold ischemia group and 879 ± 631 pg/mL for the warm ischemia group (p = 0.12). Mean sperm counts were 2.1 × 10(7) for sham, 4.4 × 10(6) for cold ischemia, and 9.9 × 10(6) for the warm ischemia groups (p = 0.48). Histological evaluation revealed significant difference in tissue injury grading with more injury in the cold ischemia than in the warm ischemia group (p = 0.01). CONCLUSIONS: In our preclinical rat model, we found no benefit for cold ischemia over warm ischemia at 30 min.