3.1 Detection of the causative agent(s) causing the death of
goats
In November 2015, most of black goats showing clinical signs of possible
PRV infection were reported in a farm in Yunnan, China. Subsequently, a
detailed survey was conducted, the symptoms in these goats included high
fever, appetite loss, skin itch and fidgety with no ages and sexes
limitation (Fig. 1A-B ). Additionally, some of the ill goats
displayed severe diarrhea (Fig. 1C ), and all of these goats
died eventually. The pathological examination showed the occurrence of
pneumonia hemorrhage, lymphadenopathy syndrome with hemorrhage, brain
hyperemia and hemorrhage in dead goats (Fig. 1D ).
Further investigation revealed that these goats were fed together with
fatted pigs only by the separation of a wall, while all pigs in this
farm had been immunized with the PRV attenuated live vaccine (Bartha-K61
strain) at the development stage of piglets. Furthermore, all animals
were fed by the same breeder.
To explore the possible causative agent(s) leading to the death of goats
in this case, the viral nucleic acids were extracted from brain tissues
of the dead goats, PCR and RT-PCR methods were performed to detect the
presence of pathogens such as PRV, RV, and GEAV. Interestingly, the
specimens presented PRV positive while RV and GEAV negative.
Furthermore, the treatment of these diseased goats with antibacterial
drugs, such as Cefatriaxone and Sulfadiazine, had poor therapeutic
effect. Meanwhile, 10 serum specimens from the fattening pigs raised
near the goats were positive for PRV gE antibody, while only 1 of
16 fecal samples from these pigs were tested positive for PRV by PCR
method (data not shown). Thus, we concluded that PRV infection was the
leading cause resulting in the death of goats.