Animal Health

Deer-like Animals (cervids) 

As with the goat and sheep-like animals, most deer will do quite well in collections around the world without vaccinations. Optimal management  techniques, proper diet, uncrowded facilities and  isolation from new stock and other ruminants that might bring disease into the facility are sufficient to maintain good health.
But there are situations where optimal density and husbandry are not practical solutions. Breeding herds of whitetail deer, reindeer and elk require higher animal densities and supplemental feeding; animal densities in zoos are quite high as well. And some diseases, like Epizootic Hemorrhagic Disease, Bluetongue. West Nile Fever and the clostridial disease are not dependent on animal density. The first three are carried by biting insects that can be blown onto the premises from quite some distance away. When the surrounding area experiences an outbreak or birds migrate through the area, good management may not sufficient to protect the deer from insect carriers. (ref1ref2ref3)

Here in Texas, there is potentially a third (genetic) problem. Breeding whitetail deer is a $900 million+ industry directed at producing “genetically superior trophy bucks” However, what “genetically superior” in this case means is a large deer with an enormous rack of antlers – not a “scrub” deer with the resistance to disease and resilience that Nature intended. (ref)

Similar genetics manipulations for specific market traits make New Zealand red deer population and reindeer quite different in their disease susceptibility than their wild cousins that are culled by natural selection. (ref)

Epizootic Hemorrhagic Disease & Bluetongue    EHD  & BTV

In the United States, more deer are vaccinated against Epizootic Hemorrhagic Disease than anything else. That is because these two diseases are the number one threat to commercial deer breeding here.  Deer concentrated in breeding facilities are hardest hit, but even those in the wild are thought to have experienced 20% losses. Most other hoofstock become silently infected and form protective antibodies without ever showing disease symptoms. (ref)

EHD/BTV are a group of related Orbivirus that sporadically (off and on) cause disease in all areas of the world where cattle and sheep production occur and the biting midges that transmit it are found.  These virus exist in many serotypes or strains with little cross-immunity protection. The primary viruses responsible for the yearly epidemics change from year to year. That is why a commercial vaccine with a stable formulation has never been available. United States laws allow for “custom” vaccine production incorporating virus or bacteria obtained from a particular herd. The vaccine has its limitations. It is not always effective and it is unclear if that is because infection was with viral strains not included in the vaccine, administration errors, specific deer genetics, concurrent disease or ineffective vaccine.

Because EHD/BTV disease often appears in a herds only every few years, it is unclear if the vaccine was responsible for the years EHD/BTV did not cause mortalities. Regulations that govern the testing of custom-made vaccines such as EHD/BTV are less stringent than those that receive permanent USDA approval. To the best of my knowledge, the producers do not have to submit evidence that the vaccines are effective.

The manufacturers, Newport Laboratories, suggest the vaccine be given to fawns at weaning and boosted in 3-4 weeks and then given to does prior to breeding to give some temporary immunity to the fawns.

Malignant Catarrhal Fever  MCF

This is another viral disease of wide distribution wherever sheep and goats are farmed or in areas of Africa inhabited by wildebeest. There are at least 10 strains of the Alcelaphine (antelope) Herpes virus that cause it (AHV-1 of wildebeest, AHV-2 caprine/goat and ovine/sheep forms).
Although one study found 61% of goats and 3% of sheep carried or had been exposed to MCF, almost no sheep and few goats become ill. (ref) Farmed deer and Zoo deer in epidemic areas, however, are particularly susceptible. (ref1ref2) It has been a particularly lethal problem in farmed European red deer in New Zealand and elsewhere. Caribou herds in close contact with sheep have also been affected.

The MCF virus has been particularly difficult to grow in the laboratory; so as of 2014, there are no commercially available vaccines – although some are in development. (ref)

Respiratory/Diarrhea Complex

Pneumonia and diarrhea are the two most common causes of death in intensively farmed deer in North America. (ref) Some producers administer, custom vaccines produced against a very large number of organisms that are commonly isolated from deer in those cases. Those vaccines commonly contain Pasteurella multocida, Fusobacterium necrophorumE. coliMannheimia haemolyticaArcanobacterium pyogenesBibersteinia trehalosi , Truperella pyogenes and Mycoplasma hyopneumoniae. Many also include EHD/BTV protection – all in a single vaccine. Their use is controversial, the benefits of the vaccine hard to evaluate.

Antibodies against three of the common cattle respiratory virus (IBR, BVD, PI-3) are found in caribou and elk – but they appear resistant to disease and generally remained free of symptoms in natural settings. (ref) The same is true in whitetail deer. (ref)

In intensive North American deer farming, deer have both been vaccinated with inactivated cattle vaccines widely used in the dairy industry. Some utilize Boehringer Ingelheim’s Triangle 9 at 12 and 16 weeks of age and boost annually.

Clostridial Diseases

Deer, like all ruminants, can be vaccinated against the clostridial diseases utilizing vaccines approved for sheep, goats and cattle. (ref) The vaccines are effective. Depending on disease experience within the group, either a Clostridium enterotoxemia/C. perfringens/tetanus vaccine is used (aka “CDT”,“CD&T or “CD3+T”) or a broad spectrum clostridial vaccines such as Novartis’ Clostri Shield 7 or Merck’s Calvary 9 (all generally at 3 months and boosted 2 wks later, then annually). Some reindeer breeders alternate years, giving the 7 or 8-way one year and the CDT the next.

Deer and other hoof stock are susceptible to fatal clostridial overgrowth when they are fed inappropriate diets that are too high in simple sugars, starch or protein (low NDF/NDR rations) (ref)  Most deer, other than elk, are browse nibblers and some, such as moose (and reindeer/caribou), do quite poorly when forced to eat  nutrient-rich diets suitable for cattle. (ref) Those differing feeding habits and abilities to process nutrients are sometimes not sufficiently appreciated. (ref) Also, as with the larger bovine ruminants, excessive consumption of farmed vs wild produce (“fast-fermentors”) favors hindgut acidosis due to their high sugar and starch content (ref) and the overgrowth of clostridia. (ref1ref2) So does the free access to rich pasture like alfalfa (lucerne), or over-access in hay or cube form.  When nutrient-rich diets cannot be avoided, vaccination against the clostridia is a valid and effective option.


Some Zoos, such as the National Zoo in Washington, DC, do make tetanus vaccination a specific goal of their vaccination program. Most others, give tetanus protection to hoofstock as as a side benefit of using a “CDT”,“CD&T” or “CD3+T” vaccine directed primarily against Clostridium perfringens. The few remaining forrest raindeer now residing at the Helsinki Zoo receive yearly vaccination with Merck’s EQUILIS® te, a univalet tetanus product designed for horses.


Certain strains of the bacteria, Escherichia coli, are capable of causing fatal diarrhea in young deer. Generally, those are offspring that, for one reason or another, did not receive sufficient colostral antibody in their first days of life. Even after the short window of time the doe’s milk antibodies can pass into the fawn’s blood stream, fawns still benefit from the protective value of antibodies present in the doe’s milk within the fawns intestine. We are still uncertain if colibacillosis scours is due to insufficient maternal antibody or if certain strains of E. coli are more able to break antibody resistance than others (invasive serotypes) , or if both those factors are involved. Collibacillosis problems are common in young elk, red deer and reindeer in farmed or crowded situations. Both diarrhea and meningitis occur.

Newport Laboratories markets a multivalent vaccine that incorporates several deer isolates of E. coli along with other pathogens. In the past, a killed K99E Colivaccine was given to pregnant does and boosted 2-4 wks closer to parturition in the hopes of boosting the antibody content of their colostrum. It has never been confirmed that that technique is effective.

Several other ruminant pathogens can be involved in scours in young deer. Merck’s Guardian®  Calf scours vaccine contains the K99E strain of E. coli along with some of those other common pathogens.  Although I know of no deer breeders using it, one respected Canadian expert considers vaccines of that nature to be, at the least, harmless. (ref) Some US fallow and whitetail breeders utilize Boehringer Ingelheim’s Bar-Guard 99TM oral E. coli K99 whole cell antibodies to provide passive (temporary)  immunity against E. coli K99 in their new born deer (2-3cc/deer).


Leptospirosis is not a common disease among deer in zoos or farmed in North America. When the disease is seen, rodent and raccoon vectors contaminating water sources and the environment with their urine are thought to be the primary sources (although even stray cats are a potential vector). (ref) In Nevada bison, wood rats arriving in round bales were thought to be the source. Leptospirosis is not a significant problem in wild deer in North America, although whitetail deer, elk and moose occasionally have antibodies as evidence of prior exposure.

New Zealand has an extensive deer and elk farming industry. It rivals, and perhaps surpasses, Texas in its scale. In New Zealand, leptospirosis has been a recurrent problem in deer herds since the 1980s. (ref1ref2)   In those herds, Leptospira pomona causes abortions, and elevated losses of nursing and recently weaned deer. Those infected with L. Hardjo-bovis are less likely to suffer overt disease. L. i.  Copenhageni has also been isolated.

Merck markets two leptospirosis vaccines approved for use in deer in New Zealand,  Leptavoid® 2 (L. .Pomona and L Hardjo antigens) approved for sheep, beef, dairy cattle, swine and deer or Leptavoid® 3 (inactivated Leptospira interrogans serotypes Pomona, Hardjo and Icterohaemorrhagiae antigens)  for beef, dairy cattle and deer. Both are extensively used in the deer industry. (ref) Young deer are vaccinate at about 3 months of age and boosted 4-6 weeks later. Unvaccinated adults get a “sensitizer” (initial vaccination) in the neck and a booster 4-6 weeks later. After that, they are boosted yearly – does about 3 weeks prior to calving. Some fallow and whitetail breeders in the USA, utilize Merck’s Covexin® 8 leptospirosis vaccine (2cc at 12 & 16 wks, boosters yearly).

Pasteurellosis  Pasteurella multocida, Hemorrhagic Septicemia

Pasteurella multocida and similar pasteurella are found the upper respiratory tract , mouth and throat (pharynx) of many animals that are not ill. In those locations, they are considered part of the animal’s natural bacterial flora. However, under stress, the organism can move into the lungs, causing pneumonia, into regional lymph nodes causing abscesses, or into the blood stream causing septicemia (“blood poisoning”).  Many strains or serovars exist. Some cause common snuffles in rabbits, some are responsible for fowl cholera of chickens, turkeys ducks and geese others are involved in atrophic rhinitis of swine. Strains appear to vary in their ability to cause disease. Most, if not all, can jump from one species to another. It is one of the organisms commonly involved in shipping fever of cattle. Outbreaks in deer often follow periods of stress. (ref1ref2)

In New Zealand deer farms and zoos, it is associated with stressors including transport, inadequate nutrition, overcrowding, concurrent viral infections, inclement weather (especially hot temperatures) heavy rains and wind and high parasite loads (particularly  lungworms). (rptref)

One of the many shotgun vaccines prepared by Newport Laboratories contains inactivated Pasteurella multocida, along with EHDV virus, BTV (bluetongue) virus, Mannheimia (Pasteurella)  Haemolytica, , Fusobacterium Necrophorum, Clostridium Perfringens Type A and Arcanobacterium Pyogenes.

Necrobacillosis Fusobacterium necrophorum, Lumpy Jaw, Foot Rot, etc

Fusobacterium disease has so many names because it presents in so many different ways and in so many species of animals. The “lumpy jaw” form is often seen in kangaroos. It is a common pathogen isolated from sick deer. In young deer, the infections is often systemic and leads to rapid death, in older deer, longer term foot or mouth and throat lesions are more common. The organism generally enters the deer’s body through a cut or scrape and forms an abscess – often not far from the point of entry. The most common form in whitetail deer are abscesses of the jaw aka “Lumpy Jaw” – It can be found alone or in association with other pathogens like Actinomyces. I have also seen it present as paralysis due to infection of the spine.  Exposure to these organisms can not be prevented as it is often present in the intestinal tract of disease-free animals. Many species of deer throughout the world develop fusobacterium-related disease when they are subjected to overcrowding, malnutrition, or chronic stress that lowers their immune resistance.

Fusobacterium is another of the antigens incorporated in Newport Lab’s bacterin vaccines for deer. Another option is Novartis’ FUSOGARD® (It is an “off label” use, The product is labeled for use in cattle). Neither have been scientifically tested for their effectiveness in deer and neither are an acceptable alternative to husbandry changes that lessen the likelihood of the disease. A primary and booster vaccination are required. The first is generally given to young fawns (1/4 CC Fusogard Sub Q at 2-3 weeks of age, revaccinated in 2-3 weeks).

A group of venerable microbiologist that direct  the IUMS, seem compelled to periodically give bacteria completely new names designed to confuse veterinarians and others that are concerned with animal health. The next two bacteria, currently called Truperella and Bibersteinia, led a number of prior lives under various different aliases.

Truperella pyogenes (= Arcanobacterium aka Corynebacterium aka Actinomyces ) pyogenes    Cranial Abscessation Syndrome CAS

Bucks are particularly susceptible to infection with this bacteria subsequent to antler damage or loss.  In those instances, Truperella can penetrate the skull and cause abscesses in the brain. The organism is also thought to be capable of causing pneumonia  – at least it is often found with other bacteria in deer with severe lung disease. It is a common isolate in postpartum metritis (after-calving womb infections) of dairy cattle. (ref)   Truperella was thought to be a common opportunistic pathogen – only taking advantaged (opportunistic) of a stress-weakened animal or working in tandem with other bacteria to cause disease. (ref)   But in some cases, it was thought to capable of causing illness in deer on its own. (ref)

T. pyogenes is another organism incorporated in Newport Laboratories multivalent inactivated deer vaccines.  Penned deer occasionally have recurrent losses due to what they still call A. pyogenes (Truperella) associated lung infections. Since the 1980s, a custom bacterin produced against A. pyogenes was the only vaccine the Kerrville Texas Whitetail Deer Center administered to their deer. In 2014, they changed to the Newport Labs 9-way due to the expense and time involved in ordering a univalent (single bacterial ingredient) custom vaccine.

Bibersteinia trehalosi aka Pasteurella haemolytica type T aka Pasteurella trehalosi, aka Mannheimia haemolytica

This is another organism that is chiefly a problem in the deer farming industry. It is also an ingredient in Newport Laboratories 9-way (multivalent)  pneumonia/fawn diarrhea vaccines. Like many of the organisms contained in that vaccine, B. trehalosi is a common inhabitant of the upper airways of deer and sheep.

Under non-stressful conditions, they causes no disease. When the animal’s immunity is decreased due to other issues, it takes advantage of the situation to invade other areas of the body. One of those underlying causes that allow B. trehalosi to become pathogenic are heavy lungworm infections due to overcrowding and cohabitation with cattle and domestic sheep. But B. trehalosi is almost never the sole underlying cause of a health problem.

Yersinia pseudotuberculosis Yersiniosis

Pseudotuberculosis or yersiniosis is another disease that occasionally causes illness in deer. The organism is widely distributed in animals so deer exposure is quite likely to occur. But like the preceding two organisms, Yersinia pseudotuberculosis only causes disease when the animals immune system has been weakened or the animals are under stress. That can be the stress associated with weaning, hard winters, crowding, poor nutrition or inclement, rainy weather. Some strains and species of farmed deer may be more genetically susceptible to yersiniosis than others. There are many serotypes (strains, serovars) of the organism. Some are thought to me more pathogenic than others. Yersiniosis is a major health issue in farmed deer in New Zealand. These are usually deer in their first year that experience severe diarrhea and subsequently die of dehydration and blood acid/base disturbances. It sporadically (occasionally) kills small hoofstock in zoos as well.

In New Zealand, Merck markets YERSINIAVAX® vaccine, composed of  inactivated Yersinia pseudotuberculosis serotypes I, II, III. The product is approved for use in deer. Two ml of the vaccine are given in the neck sc, 3-6 weeks apart – prior to anticipated periods of stress. The vaccine is said to be quite effective. The veterinary school in Utrecht, Netherlands made available another killed pseudotuberculosis vaccine for use in European zoos (Pseudovac®). I do not know if it is currently available.

West Nile Virus WNV, West Nile Fever

West Nile Fever is a mosquito-transmitted, viral disease that occurs on all continents in a wild variety of animals including deer. Most cases are subclinical – no disease signs or only mild illnesses being noticed before antibodies rise high enough to purge the virus from the animal’s body. But occasional cases lead to fatal encephalitis.

Some believe that native North American deer are naturally immune to the disease effects of WNV. That although they are commonly exposed to the virus, they overcome it without visible illness.   Others believe that the WNV does not replicate in deer. One study found 0.9% of hunter-bagged deer in New Jersey has been exposed to WNV. West Nile virus is certainly not a currently important cause of death or illness in wild whitetail deer.  One fatal case in a wild whitetail deer has been reported. (ref)

The situation in North America’s farmed reindeer has been different since 2002. Since then, Minnesota and Wisconsin breeders have experienced a number of WNV cases in their stock. Being a new problem for them, it was first suspected that the staggering and nervous system symptoms were do to Chronic Wasting disease or brain worms. Eventually WNF was found to to be the cause. Many reindeer breeders now immunize their animals using schedules and vaccines that have been successfully used in llamas and alpacas. Most use Merial’s RECOMBITEK® Equine rWNV vaccine (some had tried Zoetis’ WEST NILE-INNOVATOR in an initial trial (ref) but experienced reactions in their herds). In llamas, three IM injections of the Merial vaccine given at 3-5 week intervals stimulated adequate antibody response. I do not know if similar data on effectiveness exists for reindeer, but many reindeer breeders follow the llama protocol. The vaccinations are begun in early spring, prior to mosquito season. Vaccination of pregnant females is avoided.  Boosters given the following springs.  Some run blood titers and only give the complete initial 3-shot series to animals that have no titer.