Pistorious claimed comfortable victories in the men's 100 and 200 metres in the T44 category, while Mokgalagadi did the same in the T35 category of these events.
Both athletes also set competition records in the process.
Pistorious ran a competition record time of 11.64 seconds on a wet track in the 100m. Earlier in the day he claimed gold in the 200m in a time of 23.17 seconds.
Mokgalagadi added to this with a competition record time of 13.44 seconds in the 100m, and then claimed victory in the 200 with a time of 28.26 seconds.
Jon Fred de Koker finished fourth in the men's 200m T42 with a time of 31.20 seconds, and then took seventh place in the men's 100m T42 in 14.67 seconds.
The exploits of Pistorious and Mokgalagadi followed in the wake of Natalie du Toit's three gold medals in the pool on Saturday.
Du Toit won gold in the women's MD 100m freestyle, beating American Jessica Long with a time of 1:1.21 seconds.
Du Toit also took gold in the women's S9 100m freestyle in a time of 1:1.73 seconds, and the women's MD 50m freestyle in a time of 29.14 seconds.
Shireen Sapiro claimed the bronze medal in the women's S10 100m backstroke.