Use of a feed motivation test as a potential indicator of hunger in pregnant beef cows with varying body condition scores

In certain regions, loss of body condition over winter is a key part of the management strategy
for spring-calving suckler beef cows. While many believe that condition loss does not negatively
affect cows, as they have evolved to endure feed shortages in colder months, winter maintenance
still represents one of the highest energy demands in beef production, especially for thinner cows.
Although thin cows have an increased risk of dystocia, farmers often manage over-conditioned cows
to lose condition due to concerns about calving difficulties and to reduce feed costs. Poor nutritional
management can result in substantial condition loss in a short time. The assumption that winter
condition loss is natural highlights a gap in research regarding the potential impact on cow welfare.
The objective of this study was to develop a novel motivational conflict test and to assess whether the
body condition score (BCS) through pregnancy correlated with signs of hunger behaviour. Feeding
motivation was tested on 11 occasions between 2022-2025. In-calf suckler beef cows in Scotland
(n=523) and Ireland (n=173) were tested up to 3 times during mid-late pregnancy (n=2180). BCS
was assessed during routine handling in a cattle crush, and upon release from restraint, cows were
offered the opportunity to delay returning to their social group to consume a high-value feed reward.
Immediately upon feeding, a handler would return the cow to the herd. Cows were expected
to be motivated to reinstate social contact, so the option to stop to eat concentrates presented a
motivational conflict. Cows were scored using flight speed, duration investigating the feed trough,
latency to consume or move on from the feed, and attempts to return to the feed after being
disrupted. The effect of absolute BCS and change in BCS during pregnancy was tested using linear
mixed models. Initial data analysis of the first time point revealed that cows that experienced greater
condition loss took less time between leaving the crush and reinstating contact with their social
group (p<0.045) compared to those that maintained or gained BCS. The model had a low Pearson’s
correlation coefficient (r=0.127), suggesting the biological effect may be very small. Absolute BCS
in late pregnancy and change in BCS from mid-late pregnancy had no effect on other measures of
test performance. It is concluded that a falling body condition score has only a marginal effect on
behaviour in a feeding motivation test. Analysis of the remaining tests is ongoing.