Cattle Pregnancy Diagnosis 

he accurate and early diagnosis of pregnancy in both dairy and beef herds is essential for the maintenance of high levels of reproductive efficiency. It is required for the early identification of fertility problems at both individual animal and herd levels.

Pregnancy in cattle can be diagnosed safely and accurately from thirty days after conception by placing the Oviscan 6 transducer in the rectum (which overlies the reproductive tract) of the cow and viewing contents of the uterus. External examinations can also be made during the second half of pregnancy, though the rectal examination method can be used up to one hundred and forty days after conception. After this stage the uterus descends into the abdomen, placing the foetus beyond the depth of the beam in rectal scanning in most cases. It is suggested that scanning is carried out forty days after the bull has come out of a Suckler herd to enable pregnancy and stage of foetal development to be assessed.

Using ultrasound scanning techniques an accuracy of over 99% can be achieved, enabling fertility problems to be identified rapidly. The main advantage of scanning is that it can give accurate diagnosis earlier than rectal palpation.

The ability to estimate gestational age with reasonable accuracy is also a useful aid to management in beef herds where mating dates are not known, by allowing cows to be grouped according to expected calving dates. The technique may also prove useful to some farmers as a means of identifying multiple foetuses at an early stage.