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DISEASES SPREAD BY DOMESTIC ANIMALS TO WILDLIFE:
RISK-REDUCTION IN THE NILGIRIS BIOSPHERE RESERVE.
By Dr. Michael W. Fox
Chief Consultant/Veterinarian, India Project for Animals and Nature
Diagnosis, treatment and prevention of various communicable diseases in domestic animals are integral and
critical aspects of wildlife protection and conservation, especially in those areas where there are small communities of people
and their animals living in close proximity to viable populations of wildlife, as in the Nilgiris, Tamil Nadu, S. India, and
where it is not feasible to translocate these people and their domesticated animals, or to effectively police the grazing
of livestock in protected wildlife habitat.
Since 1996, India Project for Animals and Nature has been addressing this issue in the U.N. designated Nilgiri
Global Biosphere Reserve, where the population of 'scrub' or 'nondescript' cattle, (kept mainly for manure collection to sell
for fertilizer), water buffalo, sheep and goats, greatly outnumber the human population. Low-income farmers cannot afford
the necessary veterinary services for sick animals, especially for low-value scrub cattle, or to purchase dips and sprays
to control ticks that can spread various diseases. Because many of these animals are not only heavily parasitized, but are
also chronically malnourished, particularly during the recent prolonged droughts, their immune systems are compromised. This
can mean that the pathogens that they may carry become more virulent, according to controlled laboratory studies that have
demonstrated a relationship between an animal's nutrition and bacterial pathogenicity.
As a consequence, IPAN's free veterinary services are in great demand, and our in-field work has provided a consistent
monitor of disease problems in livestock that are of public health and economic concern to the community, and put wildlife
at risk. Also since IPAN is often called by the Govt. Forest Dept. to perform autopsies on elephants, guar, sambar, cheetal,
wild dog, wild boar, leopard/panther, and tiger, to attend to sick and injured wildlife, and to capture and vaccinate dogs
against rabies during epidemics, we have generated much in-field information about wildlife diseases. They are most often
contracted from domestic animals from the tribal and village communities in and around the State-operated 450 sq.km Mudumalai
Wildlife Sanctuary, (which is one of the major protected preserves in the Nilgiri Biosphere Reserve). This conclusion is based
on the fact that it is after disease outbreaks have been seen in the domestic animal population that they are seen in the
wild, rather than before.
IPAN also assists in Govt. vaccination programs, inoculating livestock against four major diseases that can be
transmitted to wildlife, and have been diagnosed in wildlife by IPAN, namely, Foot and Mouth Disease, Black Quarter, Anthrax,
and Haemorrhagic Septicemia. These diseases have been seen in elephants, and guar or Indian bison. Only an estimated
40 percent of the indigenous livestock are actually vaccinated, in part because of inadequate infrastructure. Lack of transportation,
effective refrigeration/cold-chain to preserve the vaccines, and inaccurate records of numbers of animals being kept, and
receiving vaccinations, mean that these and other endangered species are at risk in the Nilgiris. Canine Distemper is a common
disease that IPAN controls by vaccinating village dogs, this highly communicable disease (since dogs scavenge and hunt in
the wildlife preserve) putting the tiger, panther, wild dog, jackal, wild cat, hyena, mongoose, Palm civet, and otter at risk.
These and other wildlife species are also affected by Rabies, so IPAN also vaccinates dogs to control this disease that not
infrequently spread to people and livestock by rabid dogs. Parvovirus disease has also been diagnosed and treated in
village dogs, and is regarded as a potential zoonotic infection for susceptible wild carnivore species. IPANs spay/neuter
program has significantly reduced the dog population in several communities, and this initiative, coupled with educating dog
owners about proper nutrition, regular worming and vaccinations, has greatly improved the welfare and wellbeing of these animals,
and significantly reduced their risk to wildlife.
But the risk to wildlife posed by the high density of cattle and other domestic livestock (including poultry)
in the bioregion continues, with the following zoonotic diseases being recognized: Tick-born Babesiosis, Ehrlichiosis,
and Theileriosis, Contagious pustular dermatitis, Brucellosis (Contagious Abortion), Pasteurellosis, (Hemorrhagic Septicemia),
avian Newcastle disease, Paratuberculosis (Johnes disease), Tuberculosis, Sarcoptes (mange), Dermatophysosis (ringworm), Facsioliasis
(liver fluke disease), Tetanus, Anthrax, Leptospirosis, Infectious Keratoconjunctivitis, (pinkeye), Foot and Mouth disease,
Black Quarter, and Pasteurellosis (Hemorrhagic Septicemia).
An epidemic of Rinderpest in livestock spread to the wild ungulates, killing thousands in 1985, eliminating
90 percent of the Guar in the Nilgiris, with a serious knock-down domino effect on the tiger, panther and wild dog populations.
There are undoubtedly other zoonotic diseases that have yet to be identified. Prolonged periods of drought, that mean starvation
for herbivores because of a lack of vegetative growth (much of which is taken by livestock or cut and harvested to feed to
same), coupled with and limited drinking water sources due to hydroelectric power projects and diversion of streams for irrigation,
mean a weakening of animals immune systems, and greater susceptibility to disease, especially when they forced to share grazing,
drinking and wallowing areas with unhealthy domestic animals.
Many of these diseases, like Foot and Mouth disease, Black Quarter, and Mange lead to Myiasis, where skin lesions
are invaded by the flesh-eating maggots of parasitic flies, resulting in great suffering in afflicted animals. These parasitic
flies and ticks proliferate on sick and injured scrub cattle, and are a significant threat to wildlife of all species that
might sustain even a small cut on their bodies.
IPAN has also documented pesticide poisoning (with organophosphate and carbamate-type insecticides) of wildlife,
put out in retaliation against predators (panther and tiger), and crop-raiders (elephant, wild boar, deer) on whom urea is
also used as a poison. Vultures and other scavengers of poisoned livestock carcasses are also victim to such retaliation.
IPAN addresses this aspect of wildlife protection by reporting all such fatalities, (and also those caused by electrocution,
snares/nooses, shot-guns, and home-made bombs placed inside Jack fruit) to the authorities: and provides veterinary certification
of predator-loss by doing autopsies on farmers' animals, so they may be compensated by the Forest Dept. and then they will
have less incentive to seek retaliation. Unfortunately the compensation process is erratic at best.
IPANs veterinary attention to preventing, treating and eliminating these zoonotic diseases is coupled with teaching
livestock keepers basic animal husbandry, care and nutrition: and reducing the scrub cattle population by castrating all scrub
bulls and providing a more valuable hybrid bull whose offspring would produce more milk, a more profitable product than cow
manure from scrub cattle.
In summary, IPAN has shown that working with the people and focusing on zoonotic diseases in domestic animals
is a necessary and effective approach to wildlife protection and conservation that could well be adopted in similar bioregions
where the 'conflicts' between people and wildlife remain to be resolved.
Dr. Michael W. Fox
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