Australian Livestock Scanning Services Group

The results and recommendations from 23 years of on-property R&D with commercial cattle and sheep breeders. We specialise in precision scanning for pregnancy and ageing of foetus in cattle and for litter number in sheep and in helping to raise cow fertility and lamb survival in stud and commercial breeding enterprises.

mobile: 0428 667 567, email: fowler.doug@bigpond.com

c3. Why test for pregnancy in cows using imaging ultrasound

The use of imaging ultrasound for determining the pregnancy status of cows and heifers offers significant advantages over manual testing. These advantages are detailed hereunder:

  1. Earlier detection of pregnancy or non-pregnancy status; testing can be conducted 32 days after the end of joining versus 50 to 60 days with manual testing.
  2. Greater accuracy in determining pregnancy status; trans-rectal ultrasound pregnancy examinations are more accurate than manual palpation because it is easier to produce an image of a pregnant uterus than it is to palpate a pregnant uterus, in animals that present poorly for examination and where the pregnancy is less than 50 to 60 days days.
  3. More accurate aging of the fetus; the age of the fetus can be determined to an accuracy of days, using ultrasound, versus weeks by manual palpation.
  4. Determining the gender of the foetus; trans-rectal ultrasound pregnancy examinations enable the determination of gender.

Increased accuracy of ageing the foetus enables:

  1. The separation of artificial insemination (AI) and embryo transfer (ET) pregnancies from backup pregnancies which reduces the need to determine paternity using DNA testing.
  2. More accurate identification of bulls suspected of failing to get their cows pregnant.
  3. The allocation of heifers into early, mid and late calving groups and the identification of those cows that will calve after an "unacceptable" date.
  4. Management strategies that enable more cows and heifers to get pregnant from each joining.
  5. Identifying the most fertile breeders by determining the number of days that it takes for every naturally joined maiden heifer and first calf heifer to get pregnant. Getting heifers into calf quickly and then getting them back into calf as quickly as possible is, arguably, the most important period in the reproductive life of a cow. Indeed, some might even argue that if these two objectives are achieved in an acceptable time, the biggest barriers in the cow's reproductive life have been overcome.
  6. An improved and easier method for generating more accurate fertility EBVs for Breedplan.