I see more listeriosis in goats and sheep coming through the diagnostic lab
here than I do in dairy cattle - and had the same sort of experiences when
I was in active practice.
With the current upswing in goat numbers here in western KY, listeriosis is
running neck-and-neck with pneumonia as the #2 or #3 cause of death in
goats - still a distant second to death losses due to parasitism, but still
a significant problem.
None of these small ruminants have any history of silage/balage feeding.
Listeria is a ubiquitous soil organism, and my non-scientific(or maybe I
could call it quasi-scientific) observations indicate that feeding grain on
the ground &/or grazing low-lying swampy areas seems to predispose to
increased incidences of listeriosis.
10 years or so ago, I was involved in working up an 'outbreak' of
listeriosis in Angora goats in the bootheel region of Missouri - these
animals were being fed whole shelled corn, poured out on the ground, which
we surmised was the probably source of infection. Death losses were
running in the 10% range.
I see occasional cases of listeriosis in beef cattle with no history of
silage/balage feeding, but rarely get much in the way of historical
information regarding feeding practices, pasture conditions, etc.
Louis L. "Lucky" Pittman, Jr., DVM
Veterinary Pathologist/ Dept. Chairman
Murray St. Univ.-Breathitt Veterinary Ctr.
Hopkinsville, KY
