In another experiment, groups of 30 Wistar rats (10 males and 20 females) were fed experimental diets containing 10, 20, or 30% enzymatic fish protein hydrolyzate or a 10% casein diet (control) for 12 weeks (Ballester et al., 1977). It was not mentioned whether the study was conducted in accordance with OECD guidelines or GLP. After Week 12, the animals in each group were mated and separated into 2 subgroups of 5 males and 10 females. Females were caged individually during the pregnancy, delivery, and weaning. Dams were permitted to suckle the young for 3 weeks and the litters were routinely counted and monitored for weight gain. The authors did not indicate whether the animals continued to consume their respective diets during pregnancy and lactation.