KARACHI, Jan 22: The mystery surrounding the deadly infection in the zoo is likely to persist as officials at the zoo have chosen not to send ‘right samples’ for testing, sources told Dawn on Tuesday.

“The samples sent to the laboratory were few and not directly related to the kind of symptoms we were told the animals had before their death,” a source said, adding that the Central Veterinary Diagnostic Laboratory (CVDL), Tandojam, had now asked the zoo authorities in Karachi to send more samples.

According to the sources, the zoo had sent at least five samples taken from dead animals to the CVDL last week. The samples were reportedly taken from the spleen, liver and intestine. No sample of blood, lungs or fecal matter was sent to the lab.

“The keenly awaited lab report would come as a surprise for many because nothing life-threatening has been detected except E. coli, which is not a disease causing agent unless the animal is suffering from diarrhoea,” a source said.

E. coli, he said, was present everywhere and was considered an environmental agent and not a disease causing organism in this case because the animals did not have any symptoms of diarrhoea but rather of weakness and difficulty in breathing, according to the information sent to the CVDL.

With signs of obstruction in breathing, sources said, an examination of lung samples would have been critical.

“But no lung sample from the dead animals was sent to the laboratory. Such samples would have helped rule out the possibility of tuberculosis which was an important cause of mortality in winter, especially in deer,” they said.

Zoo officials, they said, had been asked to send in samples of sick animals’ blood, blood serum, fecal matter and lungs (in case of a post-mortem).

It is worth noting that it’s the second lab report in which ‘nothing has been detected as life-threatening’.

Earlier, the zoo had sent samples to a lab in the DHA that, too, didn't show any conclusive finding that could explain the death of animals at the zoo.

Zoo loses another deer

Another female fallow deer died at the zoo on Tuesday, raising the death toll to 23, while three others are reportedly in a serious condition, sources said.

The disease remains undiagnosed even after two weeks.

Meanwhile, Sindh wildlife department conservator Hussain Bux Bhagat visited the zoo on the Karachi Metropolitan Corporation’s request on Tuesday and gave suggestions on how to control the disease.

“I have told them that the measures taken by the zoo to check the spread of the disease are not adequate. The infected animals needed to be quarantined, preferably outside the zoo, so that the rest of the population remains safe from harm,” said Mr Bhagat while speaking to Dawn.

He also recommended that samples from infected animals should also be sent to the Central Veterinary Diagnostic Laboratory in Islamabad, which was better equipped to diagnose animal diseases.