The chronic issue of inbreeding the Punjab Wildlife is confronted with for several years took the life of a four-and-a-half-month white tiger cub (Zona) at the Lahore zoo.
In the past too, the inbreeding resulted in the deaths of several tigers at the zoo and other wildlife parks.
On the direction of the Punjab Wildlife Department director-general, a three-member committee has been constituted to probe into facts behind the death of Zona.
The committee is consisted of Wildlife director Abdul Qadeer Mahal, Biodiversity World Wide Fund for Nature director Uzma Khan and Zoo Management Committee member Dr Riffat Suleman Butt.
White tiger cub (Zona) was suffering from congenital deformities like brittle bones (suspected rickets). X-Rays show the fracturing of long bone of distal condyles.
Zoo veterinarians, who attended the postmortem at the University of Veterinary and Animal Sciences, Lahore, reported that many bones fractured previously got healed but the process of fracture was continuous due to weak bone.
Giving the background of cub’s death, the official said that brown Bengal tigress (Rozi) had given birth to four cubs. The white Bengal tiger (Sam) was the father of these cubs who is related to the same bloodline of brown Bengal tigress (Rozi). Two were stillbirths and one was born weak who died the next day. Since the tigress was unable to feed her cub, Zona was provided feeding through formula milk (Esbilac & KMR) for three months.
The cub started meat consumption and gradually reduced the milk intake. The body weight and other activities were normal, but the cub suddenly developed paraplegia of hind limbs. The recessive gene present in the white tigers causes paraplegia and immune deficiency. The inbreeding makes survival of white tigers difficult.
Quoting certain examples, the official said that a brown Bengal tigress had given birth to four cubs in Lahore Zoo Safari in April 2009. The father of these cubs was brown Bengal tiger and was shifted from the Bahawalpur Zoo. He was also of the same bloodline of the tigress.
These cubs were born normal and healthy. The cubs survived until one cub suffered from paraplegia of hind quarters at the age of three-and-a-half-months. The other cub developed deformity in fore limbs. All the four cubs died one after the other.
In 2008, the same tigress crossed again with another brown male tiger of the same bloodline and gave birth to five deformed cubs. Two cubs were born alive and three were born deformed without skull bones. The live cubs died on the same day.
He said a white Bengal male tiger was born at the Lahore Zoo in 2004. He had survived trypanosomiasis and had been weak since birth. The male was first time crossed with a brown tigress who was brought in an exchange program in 2009. The tigress gave one stillbirth and the other two cubs were not expelled out causing toxemia. The white male tiger (Sam) mated brown tigress (Rozi), resulting again in weak offspring this year.
The official said that according to the track record of bloodline of tigers at the Lahore Zoo, three tigers were imported in 1971 and 1975 and now they all have died. Only one female (Mary), 14 years of age, could survive.
In 1982 and 1984, two pairs were imported and thus the total five tigers remained in Lahore Zoo. Only a few cubs from the two pairs survived.
In 1992, white Bengal tigress (Bush) was brought from Karachi. The cubs from these pairs were shifted to other parks and zoos. In 1997, trypanosomiasis broke out and tigers started vanishing from the Lahore Zoo.
The Lahore Zoo had left with only one white male tiger (Sam) and one Brown tigress (Rozi). The two white tigresses (Jati and Mohni) were imported to solve the inbreeding issue. But the genetics of these animals is still unknown.
All tigers at zoos and parks in Punjab should be checked for strong genetics and be paired to get strong cubs. All white tigers are carrying recessive genes and should be paired with brown tigresses after getting gene sequencing.
The experts were of the opinion that Zona was suffering from the same congenital problem as the blood profile and fecal reports did not show any abnormality.
The case has been discussed with senior doctors and it is treated symptomatically and is under close observation.
Several national and international experts consulted during the treatment of the cub by zoo vets say that proper breeding plan with one record unit should be made for whole of Punjab and paved floor be given to animals in the display area. Artificial insemination could also solve the problem of inbreeding issue in tigers, they said.
Former Lahore Zoo veterinarian Dr Riffat Suleman Butt, Dr I.H Kathio (USA) and San Diego Zoo curator Gary were also consulted for the cub’s treatment.
Lahore Zoo Director Iqbal Khalid said the introduction of new blood in the existing stock of tigers was badly needed to prevent further misfortune of loss of this feline species through inbreeding.