Abstract:
Abortions in domestic ruminants cause significant economic losses to farmers. Determining
the cause of an abortion is important for control efforts, but it can be challenging. All available
diagnostic methods in the bacteriology laboratory should be employed in every case due to
the many limiting factors (autolysis, lack of history, range of samples) that complicate the
investigation process. The purpose of this study was to determine whether the recovery of
diagnostically significant isolates from domestic ruminant abortion cases could be increased
through the use of a combination of the existing aerobic culture and Brucella selective method
with methods that are commonly recommended in the literature reporting abortion
investigations. These methods are examination of wet preparations and impression smears
stained by the modified Ziehl–Neelsen method, anaerobic, microaerophilic, Leptospira,
Mycoplasma and fungal culture. Samples of placenta and aborted foetuses from 135 routine
clinical abortion cases of cattle (n = 88), sheep (n = 25) and goats (n = 22) were analysed by the
new combination of methods. In 46 cases, bacteria were identified as aetiological agents and
in one case a fungus. Isolation of Brucella species increased to 7.4% over two years compared
with the previous 10 years (7.3%), as well as Campylobacter jejuni (n = 2) and Rhizopus species
(n = 1). Salmonella species (5.9%) and Trueperella pyogenes (4.4%) were also isolated more often.
In conclusion, the approach was effective in removing test selection bias in the bacteriology
laboratory. The importance of performing an in-depth study on the products of abortion by
means of an extensive, combination of conventional culture methods was emphasised by
increased isolation of Brucella abortus and isolation of C. jejuni. The combination of methods
that yielded the most clinically relevant isolates was aerobic, microaerophilic, Brucella and
fungal cultures.
