Volume 97, Issue 4, April 2014, Pages 1877–1884
Hot topic: Brown marmorated stink bug odor compounds do not transfer into milk by feeding bug-contaminated corn silage to lactating dairy cattle
Abstract
Brown marmorated stink bug (BMSB; Halyomorpha halys)
is an emerging invasive species of grave concern to agriculture as a
polyphagous plant pest with potential negative effects on the dairy
industry. The purpose of this study was to determine the risk of
including BMSB-contaminated silage in lactating dairy cow rations.
First, 6 dairies, either highly infested (n = 3; 30 to 100 bugs per
stalk) or not infested (n = 3), were sampled to assess the prevalence of
bug secretion compounds tridecane (major component) and E-2-decenal
(stink odor component) in silage and milk. Second, using wild BMSB, a
mini-silo dose-response experiment (adding 100, 50, 25, 10, and 1
freshly crushed bugs/0.5 kg of chopped corn) was conducted to assess the
effect of ensiling on BMSB stink odor compounds. Finally, synthetic
BMSB stink odor compounds (10 g of tridecane and 5 g of E-2-decenal)
were ruminally infused twice daily over 3 d, and samples of milk,
urine, and rumen fluid were collected to evaluate disposition. Bug stink
odor compounds were sampled by solid-phase microextraction (SPME) and
analyzed by gas chromatography-mass spectrometry (GC-MS). Milk
production and feed composition were unaffected when BMSB-contaminated
silage was fed. Moreover, no E-2-decenal was detected in silage
or milk (detection threshold = 0.00125 μg/mL). The dose-response of
tridecane in mini-silo samples exhibited a linear relationship (R2 = 0.78) with the amount of BMSB added; however, E-2-decenal
was completely decomposed and undetectable in spiked mini-silos after
ensiling. Both synthetic secretion compounds infused into rumen were
undetectable in all milk and urine samples. E-2-Decenal was not
detectable in rumen fluid, whereas tridecane was detected only at 15
min postinfusion but not present thereafter. Feed intake was unaffected
by infusion treatment and BMSB secretion compounds (E-2-decenal and tridecane) were not observed in milk. E-2-Decenal
and tridecane from the metathoracic gland of BMSB are not able to
contaminate milk either due to the ensiling process or because of
metabolism within the rumen. Concern over BMSB stink odor compounds
contaminating the fluid milk supply, even on highly infested farms, is
not warranted.
Key words
- dairy cow;
- brown marmorated stink bug;
- milk;
- stink bug odor
Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
