The figure shows the frequency of cows non-pregnant. Thus, in start of lactation all cows are non-pregnant and from around day 60 and onwards animals get pregnant. The cows in the X-Zelit group are getting pregnant earlier compared to the cows in the control group. Looking at the time point where 50 percent of the animals are pregnant, we can see this happen around day 70 for the X-Zelit group and day 90 for the control group. Thus, the number of empty days are highly reduced.
The effect of X-Zelit on reproduction can also be read at day 150. At this time point 30 percent of the animals in the control group are still not pregnant, whereas in the X-Zelit group only 10 percent of the animals are not pregnant, suggesting a higher reproductive performance for the X-Zelit group.
The results are indicating that reproduction is very much influenced by the calcium balance of the cows at calving. Therefore, the calcium status of the cows is not only a temporary problem at calving – it is influencing the production level during the whole lactation. Getting the calcium level stabilised at calving is highly recommended.