8.1.3 What is the effect of vaccination with Enterisol® Ileitis on body weight variation?

Pigs vaccinated with Enterisol^® Ileitis show a lower slaughter weight variation than non-vaccinated pigs (Table 8.1.3 a; Figure 8.1.3 a). The lower percentage of pigs outside the optimal weight window and the lower percentage of lightweight pigs leads to significantly reduced weight discounts and an overall better price per kg carcase weight for vaccinated pigs when compared with non-vaccinated controls.

Figure 8.1.3 a
Distribution of the carcase weight in vaccinates and controls.

Table 8.1.3 a
Variation in carcase weight dependent grades in the trials across Europe.

^a,b Means and frequencies in the same row without a superscript in common differ significantly (p ≤ 0.05)

In practice, it is much easier to control losses due to overweight or excessively fat pigs by sequential pre-slaughter sorting compared to moving lightweight pigs into the desired weight group. The disturbed animal flow, due to increased weight variation, creates health risks by inter-group mixing of animals. Nevertheless, additional costs at the farm, due to extra labour for sorting and extra transportation to the slaughterhouse, are not specified in the calculation, but can surely be reduced by vaccination as well. The simultaneous, homogenous exposure of pigs at a specific time point by oral vaccination will reduce the number of naïve pigs in the herd (Guedes and Gebhart 2003). This mechanism might possibly contribute to the overall reduction of Ileitis associated weight variation in the presented trials.