The 18-year-old tigress died due to old age, official sources said.
Kusum was earlier kept off display since 2014 following illness and reduction in her movement. She was kept in the feeding chamber of the safari in the zoo.
The zoo authorities informed that she had reduced food intake after falling sick in July 2017 and completely left diet in the last three days.
Kusum had bred seven off springs in three litters (5 white and 2 normal) and all total 18 to her credit, sources said.
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