Short Term, Low Temperature Preservation of the Pacific Whiteleg Shrimp Penaeus vannamei Spermatophores

The study aimed to assess the efficacy of short-term (≤24 d), low-temperature preservation of Pacific whiteleg shrimp (Penaeus vannamei) spermatophores. A total of 432 spermatophores from 216 males, averaging 35.1 ± 3.1 g in weight, were preserved in mineral oil at temperatures of 10 °C and 24 °C. Sperm viability was monitored every 2 d over 24 d, evaluating fertility percentage, hatching rate, and nauplii deformity in females artificially inseminated with the preserved spermatophores compared with naturally inseminated females. In the control group, throughout the 24-d experiment, the average fertility, hatching rate, and nauplii count per gram of female were 66 ± 7 %, 94 ± 6 %, and 4,875 ± 148 nauplii g-1, respectively. Females inseminated with spermatophores stored at both temperatures exhibited a gradual decline in all measured parameters. Although spermatophores stored at 24 °C showed a linear decrease in fertility over time, this preservation technique proved to be effective for short-term storage of sperm, with good average hatching for up to 18 d at 10 °C (>50 %) and 8 d at 24 °C (>40 %). Notably, this technique has been successfully employed for the past seven years to facilitate controlled crossbreeding, mitigating the risk of pathogen contamination.