One measure of the success of somatic cell nuclear transfer (SCNT) cloning procedures is the percentage of pregnancies that result in live births.
Table 1 shows compile data from various scientific papers regarding the success of SCNT in four different mammalian species:
| Species | Number of pregnancies | Number of live births |
|---|---|---|
| Cow | 85 | 29 |
| Pig | 140 | 18 |
| Rabbit | 48 | 11 |
| Cat | 12 | 3 |
Calculate the percentage of pregnancies that resulted in live births in cows and pigs. Give your answers to either 2 or 3 significant figures.
Compiling results from different researchers can present difficulties because their experimental conditions may not have been fully standardized. List three factors related to the surrogate mothers or the biological materials used that should ideally be controlled when comparing data from different SCNT investigations.