Quite a lot, actually.

Nutrition has a huge influence over follicle development, oocyte number and quality, ovulation, pregnancy, birth, mothering ability, and the ability of the mother to regain her body condition and return to a normal ovulation cycle postpartum.

The relationship is not as linear as one might think. It is not a simple case of "more energy is best," with numerous studies showing that what may be good for one stage of the cycle can actually be detrimental in another.

A common problem in animals where pregnancy scans are not performed is for the animal to be overfed "in case she is pregnant." While one may think the only harm this may do is to the owner's pocket, this unnecessary energy boost can actually delay the resumption of the normal oestrous cycle. That is to say that, once the owner finally realises that their animal is not pregnant, the changes they have made to her diet may further delay the possibility of remating her.

At the other extreme, many animals suffer from appetite loss from as early as 6 weeks before giving birth (very common in ewes, for example). If the animal is not known to be pregnant and nothing is done to supplement her diet, she may lose vital body condition, which will have a negative impact on the health of her young, her mothering ability and milk yields, and her return to a normal body condition and cycle postpartum.

An animal has very different nutritional needs at different stages of pregnancy or non-pregnancy, so the earlier we can detect pregnancy, the sooner these needs can be met accurately. For commercial animals in particular, therefore, ultrasound offers a unique opportunity to detect pregnancy well before any visible signs can be seen, allowing the needs of the animal to be met optimally.

Did You Know?

Ultrasound allows you to detect not only the here and now, but to a certain extent, to look back in time! By putting a probe over the back of a commercial animal (a sheep, for example) - and this works best with a linear probe - you can see fat layers laid down over time (a bit like tree rings!). Times of rapid weight gain and loss are very clearly identified in the fat layer under the skin, and are marked by bright white horizontal lines.