The researchers have already determined that a significant portion of the reindeer population is plagued by Brucella suis, bacteria that cause a serious form of brucellosis.
The infectious disease attacks the reindeer's reproductive system and, in turn, causes stillbirths or abnormally small offspring. The bacteria also trigger bursitis, a swelling of the joints that is a particularly menacing condition for a nomadic animal.
"Our initial results indicate that brucellosis is a problem. We found a higher prevalence than we expected," Haigh said.
"There is little doubt that action needs to be taken to try and bring this situation under control, both for the health of the animals and for the well-being of the Tsaatan themselves," he said.
Nansalmaa believes the blood parasite anaplasma has also infected and caused sickness in the herd.
Keay, the Colorado wildlife biologist, said, "The health of the herd is substandard. It will remain insufficient to sustain a pastorally dependent human culture if action is not taken."
In the past the Tsaatan depended on state-financed veterinary care provided by Mongolia's communist government, which was toppled in a bloodless, democratic revolution 15 years ago.
The country now enjoys democracy, but herders must fend for themselves in a free market economy. Today the Tsaatan depend on animal care provided by specialists like Haigh, Keay, and Nansalmaa, who visit the taiga during their personal vacation time.
Inbreeding and Economics
Bulls and cows in the Tsaatan herd grow velvety racks of antlers. Most of the reindeer have coats of mottled charcoal. A few are pure white.
Very few bulls remain to impregnate cows, making inbreeding a pressing concern. Inbreeding causes bone deformities, vulnerability to disease, and lameness, a potentially fatal affliction. (Wolves can kill weak or slow reindeer when they fall behind the fast-moving herd.)
"In 1962 and again in the late eighties, the government of Mongolia brought in reindeer from a Siberian herd to replenish the genetic stock of the reindeer in the taiga," Nansalmaa said.
"But since the fall of communism, with state financial and veterinary support for herders ending, inbreeding began, and its negative consequences were soon apparent."
Tsaatan herder Bayandalai owns 97 reindeerthe largest herd on the taiga.
"The reindeer our ancestors used to herd were healthy," he said wistfully. "Today I have only one wish, and that is for the government to bring in reindeer from Siberia, Scandinavia, or Canada. If not reindeer, then reindeer semen."
"Herders here represent one of the last truly nomadic cultures on Earth," Nansalmaa said. "I'll do what I can to preserve the health of the herd by analyzing blood and tissue samples."
"But without a solution to the problem of inbreeding," she continued, "the herd's health will remain compromised."
The veterinarian hopes the nomads resist the temptation to move to lower altitudes. Some Tsaatan have brought their reindeer to a lake where, for a fee, they pose with their reindeer for tourist cameras.
"Moving the animals to lower regions means the reindeer are stationary and living in hotter climates," Nansalmaa said.
"Remaining in one place is unsuitable for animals used to constant movement. And hotter temperatures in the summer leave the animals vulnerable to insects and the parasites the insects carry, making them weak just as winter arrives."
Nansalmaa and her colleagues will use the data they've collected to recommend antibiotic and vaccine treatments for the herd.
At the herders' request, the specialists also plan to begin a program of artificial insemination next year. Donor bulls in Canada have been identified.
"Artificial insemination is a key to regenerating the size and [genetic] quality of the herd," said Haigh, the University of Saskatchewan veterinarian.
The practice has proven effective in boosting the vigor of struggling animal populations, according to Keay.
The health of more than an animal population lies in the balance.
Speaking of the Tsaatan, Nansalmma said, "They have a unique relationship with their reindeer. We want to help the taiga people live a full life, as their ancestors did for generations."
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