Bacterial Diseases of Wild Animals

Bacterial Diseases of Wild Animals

Bacterial Diseases of Wild Animals are given more priority in the recent days due to the fact that conservation of any wild fauna can not be achieved fully, unless due efforts are equally given pertaining to the assessment of health status and the disease management, in the concerned wild animal species.

Bacterial diseases are in plenty in case of wild animals esp. the captive wild animals and they pose problems in the diagnosis as well as the treatment.

Hence, one should have a thorough understanding of various bacterial disease conditions that affect commonly the wild animals belonging to multiple taxonomic classes or groups.

Significant Bacterial Disease

Tuberculosis

The Tuberculosis disease is chronic in nature and is caused by Mycobacterium tuberculosis, Mycobacterium bovis and Mycobacterium avium.

This Tuberculosis caused by Mycobacterium bovis is very common in general. These organisms are acid-fast in nature.

Almost all species are affected in general. The disease is somewhat widely prevalent in a captive wild animal atmosphere.

Commonly affected species are listed below:

  • Mammals (Non-human primates, deer, antelopes, felids, ursids, canids, elephants etc).
  • Aves (Raptors, Psittacine birds, Passerine birds, Anseriform birds etc.)

Mode of spread and significance

Discharges from the body like vaginal discharge, exudates from the fistulous tracks, milk, sputum and excreta like feces and urine get contaminated with these microbes.

The bacterial organisms are also shed in exhaled air also. This disease is zoonotic in nature.

Symptoms

  • Emaciation despite moderate to good nutrition.
  • Anorexia.
  • Weakness.
  • Mild pyrexia.
  • Low pitched cough may be seen.

Diagnosis and therapy

By culture tests, ELISA tests, PCR tests etc. Tuberculin tests may have false positive results some times.

In dead animals, the tubercles may be seen in various organs esp. the lungs. Smears from the lesions may be subjected to the staining for the diagnostic purpose.

The therapy consists of usage of combination of drugs like isoniazid, ethambutol, pyrizanamide and rifampin. Enrofloxacin may also be used in the combination.

Paratuberculosis

The disease is caused by Mycobacterium paratuberculosis and is a rod-shaped organism resembling the tuberculosis bacillus.

Species affected

Mostly bovids, wild sheep, wild goat, antelopes, cervids etc. may get affected.

It was even reported in equines and swines have been reported as the carriers.

Mode of spread and significance

Ingestion of food and water contaminated by the feces of infected animals.

Intra-uterine transmission occurs at a fifty percent incidence from the infected mother.

This disease is the one causing specific-infectious enteritis, in the affected wild animals.

Symptoms

Profuse diarrhea that is more often odorless, and there is no accompanying tetanus. There appears to be no correlation between the severity of the clinical syndrome and the severity of the lesions.

Emaciation and intermandibular-oedema.

Diagnosis and therapy

By culture, PCR tests and by staining with acid-fast preparations like Ziehl-Neelsen and Ponder-Kinyoun stains. Also, biopsies of lymph nodes, FAT, fecal culture, complement fixation tests, stained fecal smears also help the diagnosis.

In dead animals, hypertrophied intestinal mucosa is seen and the primary site of infection is the lower gastr-intestinal tract mainly the posterior jejunum and ileum. Most of the bacilli are seen in the macrophages and giant cells.

There is no true therapy for Johne’s disease but general therapy may be carried out to ameliorate the clinical signs.

Fluids and vitamins may be given taking care of the animal’s condition.

Pasteurellosis

Pasteurellosis is a bacterial infection that is commonly encountered in case of multiple species of wild animals.

Pasteurella multocida is the commonly encountered etiological agent in this and however, the pasteurellosis in marsupial like species may also have affections by Pasteurella haemolytica  organisms.

Avian cholera caused by pasteurella organisms is found commonly around the monsoon period in the captive semi-aquatic and aquatic aviary species. The incidence of pasteurellosis is a world wide one.

Species affected

This disease is documented in various species of animals including elephants, cervids, antelopes, ursids, felids, elephants etc.

Even marsupials like kangaroo get affected by this infection.

Mode of spread and significance

Organisms get passed through contaminated food materials by infected rodents etc. Overcrowding and strenuous events like a prolonged transport etc. lead to the precipitation of this disease condition in case of wild animals. It is not uncommon to find the peracute occurrence of this disease condition.

This is a highly infectious disease in general.

Symptoms

In elephants, the symptoms may be similar to those of anthrax. The death occurs within 12 hours in case of acute cases.

The clinical symptoms are often related to the pleuropneumonia, dyspnoea, gastroenteritis in addition to the pyrexia, anorexia and depression.

Diagnosis and theraphy

By PCR, examination of the heart blood-smear, biological test and culture from oral or nasal mucus and some times from feces help the diagnosis, in addition to the ELISA based tests etc.

Post mortem reveals splenomegaly, petechial haemorrhage on lungs, epicardium, kidneys etc. Respiratory tract (upper regions)infections including tracheitis and red hepatization of the lungs are the common findings. are common and if aves are affected, it may be having necrotic foci on liver along with the petechial hemorrhage on epicardium and lungs.

Tetracyclines, sulphonamides and fluoroquinolone compounds may assist the treatment of this condition in a successful manner.

Leptospirosis

This is a significant disease that is caused by multiple serovars of the leptospires. Affected animals whether it is wild in free ranging or captive status become highly dull and lethargic.

This disease has been documented in multiple species of wild animals, in general.

Species affected

Most of the wild animal species get affected like ruminants, ursids, proboscids, felids,canids, marsupials and monotremes, peccaries and suids, procyonids, rodents and lagomorphs, rodents, viverrids, insectivores, pinnipeds etc.

Outbreaks have been documented in case of non-human primates esp. the baboons and macaques. Rodents including mongooses act as carriers for this disease.

Mode of spread and significance

Spread is mainly by the contaminated urine sample by rodent-urine etc.

This disease is of zoonotic significance and affected human may reveal symptoms like myalgia, head ache, fever, sore throat, joint and neck pain, abdominal cramps etc.

Diagnosis and therapy

Serolgoical examination, culture, MAT, PCR finding of the organisms in the tissues etc.

Therapy consists of usage of compounds like streptomycin, penicillin, tetracyclines esp. doxycyclines etc.

Anthrax

Anthrax itself is a well-known disease with a great degree of public significance.

In case of elephants, sub-cutaneous oedema may be found, along with bursting of few swellings on body.

However, bloody discharge from natural orifices is a commonly found symptom in case of wild bovids, cervids, antelopes etc.

This disease has been documented in felids, canids, perissodactylids, primates, wild suids etc.

Brucellosis

This has marked public health significance and the reports on the documentation of this dangerous disease among wild stock are many.

This disease has been documented in case of chital, blackbuck etc. In general, it can be quoted that the hooved mammals, lagomorphs, rodents and canids get affected by this disease condition.

Tetanus

Clostridial organisms cause this condition in which muscular rigidity is the prominent feature. This is commonly noticed in captive elephants that met with injuries, non-human primates etc.

In case of affected elephants, this caused death in large number of elephants.

Clinical symptoms comprise diarrhea, loss of appetite, listlessness and death.

The therapy consists of administration of antitoxins and high levels of antibiotics.

Botulism

This is caused by Closridium botulinum that affects the anseriformes and mink.

The ingestion and wound infections are the primary routes of this infection in case of wild animal species.

Affected species may reveal the neurological symptoms that are often fatal.

Klebsiella Infections

Klebsiella and other vector borne gram negative bacteria (pseudomonas) are primary opportunists affecting non-human primates.

Klebsiella is present in stagnant water, dirty drinking receptacles and soil and as flora of alimentary tract.

Colibacillosis

These infections are caused by Escherichia coli organisms affecting the wide variety of birds as well as the mammals esp. the neonatal animals.

Incidences have been found through out the world among the various wild animal species.

Fecal-oral route is the mode of transmission of these organisms, in most of the conditions.

Enteritis occur in the affected wild animal species. The culture tests may assist the confirmation of this microbial infections.

Campylobacteriosis

This was earlier classified as a member of the family vibriacae but recently re-classified as a separate group.

Campylobacter jejuni causes entero-colitis in a variety of mammals and birds including man. This is frequently reported in non-human primates.

Salmonellosis

This is more common in most of the animal species esp. in case of non-human primates and reptiles.

The affected animals may suffer from severe diarrhea and is of zoonotic significance.

In wild animals like felids, salmonella typhimurium and other species cause this disease condition the gastro intestinal signs in addition to septicemia occurs.

Documentations are available on isolation of the most serious human pathogens of the groups namely Shigella dysenterriae type I and Salmonella typhi.

Symptoms comprise weakness, edema of face and neck and diarrhea with mucus and /or blood.

Other Bacterial Diseases of Wild Animals

Most of the carnivores get affected by the infections with Streptococcus sp. , staphylococcus sp. and Corynebacterium sp. frequently.

These organisms may be cultured from animals with neonatal polyarthritis, pneumonia, septicemia and abscesses.

Similarly, corynebacterium pyogenes is found with abscesses, arthritis, metritis and cystitis.

Colic like disorders and corneal opacity like conditions may be encountered in animal like elephant.

Scroll to Top