Red mite (PRM) is the tricky issue in poultry welfare and performance. Besides, the
excess use of synthetic compounds to control PRM causes risk of resistance and bioaccumulation
that alerts public health concern. Hence, sustainable alternatives are in demand.
Natural essential oils (EOs) are the promising solution thanks to their documented
repellent effect. The objectives of this study were to evaluate a standardised essential
oil mixture (STEOs), named Nor-Mite, in controlling PRM and its possible residues
in eggs.
Nine hens were divided into 2 groups: STEOs group fed (n=4) with standard feed supplemented
with STEOs; CT group (n=5) received an un-supplemented standard feed. The repellency
of hens to PRM was determined by letting 50 starving female PRMs freely choose hens
for blood meals through a Y-shaped olfactometer route. Residues were analysed using
an adapted GC-EI-MS method on eggs laid by STEOs- supplemented hens during 10 months
compared to eggs from un-supplemented hens. Two major compounds, geraniol and eugenol
were targeted.
In vivo study showed that up to 78% of tested PRM was recorded feeding on CT hens while only
14% of PRM choose STEOs hens. These results showed significant repellent effect against
PRM of STEOs hens compared to CT hens (P<0.001). By detection limit, no aromatic compound was detected from all eggs of both
groups.
STEOs demonstrated the via-feed-supplement repellent effect. Residual accumulation
in eggs laid by hens supplemented with STEOs in feed for 10 months was absent. Thus,
indicating that dietary STEOs is the efficient, residue-free solution to prevent PRM.
