After reviewing test results and other facts, experts ruled that five of the zebras died from infections with five kinds of bacterium and the four others died after fighting each other, Md Jahidul Kabir, project director of the safari park, said on Tuesday.
The bacteria were identified as streptococcus, E coli, costodium, salmonella and pasteurella. The zebras also ate green grass excessively, said Jahidul.
The experts recommended changing the location of the zebras and the water for them, vaccinating them, and feeding them high quality grass grown in the park.
Samples from the dead zebras were sent to the Institute of Epidemiology, Disease Control and Research and the university. The results arrived on Monday night.
The deaths of the zebras at the African Core Safari range of the park occurred between Jan 2 and Jan 24, but the authorities kept the issue under wraps until Monday. The park now has 22 zebras.
“Zebras move in herds. There was no symptom manifested in this group. As they are wild animals, we couldn’t go near them,” said Jahidul, the project director.
The affected animals were seen isolating themselves from the herd and fell to the ground: they apparently suffered from respiratory distress and swollen stomachs before they died, according to Jahidul.
Samples were sent to the lab for PCR tests to find out if the zebras died from coronavirus infections, but all tests yielded negative results. The authorities checked the foods and ruled out food poisoning.
Most of the dead zebras were female and born in the park.
The safari park has a strong security system, the project director said, adding there was no chance for outsiders to enter and poison the animals.