Semen Evaluation. Stallion AI Services performs tests on all semen collected at the centre to make sure only the best quality semen is used for AI. More indepth evaluations are also carried out on frozen semen and this service is also available for stallion owners wishing to know the quality of their stallionsâ semen.
Ultrasound is one of the screening tests that may be done in the first trimester to look for birth defects, such as Down syndrome. The first-trimester screening test uses ultrasound to measure the thickness of the skin at the back of the baby's neck.
  Answer   An ultrasound may be able to detect multiple embryos as early as your third week of pregnancy; However, the ultrasound will be most reliable at detecting â¦ a multiple or twin pregnancy at around 6 to 8 weeks.9 people found this useful.aternal twins (Two (2)separate eggs that are both fertalized) can be seen on your first ultrasound, as early as 6 weeks or 4 week if your doctor orders a vaginal ultrasound.