Chiroptera

Question 1

List two differences betweeen suborders Megachiroptera and Microchiroptera

Answer 1

Megachiroptera: fruit bats (eat fruit/nectar/pollen), good eyesight, good climbers, have claw on each wing. Microchiroptera: feed variety insects, mammals, blood, poor eyesight, rely on echolocation (F835)

Question 2

Phlebotomy sites in bats?

Answer 2

small bats: cephalic vein, infrafemoral, uopatagial, >100g bats: median vein (W36)

Question 3

Cardiac alterations common with hibernating bats?

Answer 3

T and R waves fuse, bradycardia, supraventricular arrhythmia, 2nd degree AV block (W36)

Question 4

What condition is represented by these liver histopath images, Rousettus aegyptacus, Prussian blue stain?

Answer 4

Iron overload (ZP25, F835)

Question 5

Iron overload in frugivore bats is associated with what lesions?

Answer 5

Hepatic necrosis/hemosiderosis/hemochromatosis and Myocardial fibrosis (ZP25)

Question 6

List treatment options for iron overload in frugivore bats

Answer 6

dietary chelators (tannins), phlebotomy, injectable chelators (F835)

Question 7

Myocardial fibrosis in captive frugivorous bats is associated with what dietary issues?

Answer 7

iron overload and hypovitamonsis E (ZP25, F835)

Question 8

Captive frugivoree bat diets are typically low in what?

Answer 8

Vit E, Vit A, and Ca (F835)

Question 9

What lesions are associated with flurosis (excess dietary fluoride) in bats?

Answer 9

hyperostosis, multifocal bony proliferation that is periauricular (not involving joints) (ZP25)

Question 10

Cynopterus brachyotis developed generalized paresis from what medication?

Answer 10

Ivermectin (Dog-faced fruit bats) (ZP25)

Question 11

What accounts for highest number of bat mortalities worldwide?

Answer 11

Wind turbine interactions, esp migratory species that roost in trees (ZP25)

Question 12

Excessive granulation tissue (nodular fibroplasia) in bats can be mistaken for what other condition?

Answer 12

Spindle-cell sarcomas (ZP25)

Question 13

Proposed cause of “square-eared anomaly” in free ranging Myotis spp?

Answer 13

Frostbite - can reduce ear height by 50% in mouse-eared bats (ZP25)

Question 14

Alopecic syndrome in fruit bats is most prevelant when?

Answer 14

dry season and in females, suspect nutrition or edocrine etiology (F835, ZP25)

Question 15

Most common neoplasm in Egyptian fruit bat (R. aegyptiacus) and suspected etiology

Answer 15

Hepatocellular carcinoma and cholangiocarcionoma, suspected from iron overload (ZP25)

Question 16

New genus of what virus causes joint swelling and osteomyelitis in Eptesicus fuscus?

Answer 16

Poxvirus, also causes more typical cutaneous lesions in Miniopterus schreiberssi (ZP25)

Question 17

Lyssaviruses in bats is associated with what clinical manifestation

Answer 17

fatal encephalitis (ZP25, F835)

Question 18

Which bacterial pathogen lead to respiratory and skin infections in 70% of Egyptian fruit bat colony?

Answer 18

Yersinia pseudotuberculosis, caused necrotizing abscesses in liver/spleen (ZP25, F835)

Question 19

What organism causes the histopath lesions on the patagium of this Myotis lucifugus, Periodic acid-Schiff stain? (Fig 25.16, ZP25)

Answer 19

Pseuogymnoascus destructans (ZP25, F835)

Question 20

What type of organism is Pseuogymnoascus destructans?

Answer 20

Psychrophilic, keratinophylic, saprophytic fungus; cold-loving fungus (ZP25)

Question 21

Pseuogymnoascus destructans leads to what pathognomonic lesions?

Answer 21

cupping erosions through basement membrane, PMS and GMS positive fungal hyphae in ulcerations; no inflammation (ZP25)

Question 22

How is Trichophyton redellii (mycotic dermatitis) differentiated from Pseuogymnoascus destructans?

Answer 22

Both cause mycotic dermatitis in bats, Trichophyton reedelli is not on muzzle, no deep dermal invasion, inflammation present (ZP25)

Question 23

What nematode leads to neuro signs similar to lyssavirus in bats?

Answer 23

Angiostrongylus cantonesis, rat lungworm (F835, ZP25)

Question 24

Which common intestinal nematode lead to death in juvenile flying foxes by aberrant migration?

Answer 24

Toxocara pteropodis (F835, ZP25)

Question 25

Which parasite is the cause of the gross image and histopath of the kidney of Eptesicus fuscus?

Answer 25

Renal coccidiosis (ZP25)

Question 26

Body temp was higher when measured by which method in Livingstone’s fruit bats under anesthesia with sevo?

Answer 26

SEVOFLURANE ANESTHESIA IN LIVINGSTONE’S FRUIT BATS (PTEROPUS LIVINGSTONI)

Alberto Rodriguez Barbon, Gale Glendewar, Aimee L. Drane, Robert Shave, and Andrew Routh

Journal of zoo and wildlife medicine (1042-7260), 48 (4), p. 1081. 2017

Fourteen captive Livingstone’s fruit bats (Pteropus livingstonii) were anesthetized for routine veterinary health checks, including echocardiography, using sevoflurane. In addition, three specimens suffering from cardiac disease and a pregnant specimen were anesthetized for clinical assessment. No anesthetic complications were observed in any of the specimens. Significant differences in the core body temperature were found between the esophageal and rectal measurements. A significant decrease in blood glucose was noted through the anesthesia, suspected to be related to an extended fasting period prior to the procedure.

Key Points:

Sevoflurane induction time was slower than isoflurane in another Pteropus study

Esophageal temp < rectal temps

Conclusions: When anesthetizing Livingstone’s fruit bats, rectal temperatures are higher than esophageal temperatures.

Question 27

What were the most important specimens of epizoological importance for introduction of new rabies variants in the US?

Most important specimens of epizoological importance for translocation events?

Most important for host shift events?

Answer 27

Evaluation of rabies virus characterization to enhance early detection of important rabies epizootic events in the United States.

Pieracci EG, Chipman RB, Morgan CN, Brown CM, Kirby JD, Blanton JD, Velasco-Villa A, Martin AD, Nelson KM, Singh A, LeMasters E.

Journal of the American Veterinary Medical Association. 2020 Jan 1;256(1):66-76.

Key Points:

Five wildlife terrestrial reservoirs in US: striped skunk, raccoons, mongoose, arctic fox, grey fox

5 variants occurred due to host-shift events from dogs to California skunk, north central skunk, mongoose, Texas gray fox, and Arizona gray fox

2 variants from bats to south central skunk and raccoons

Most important specimens of epizoological importance (SEIs) for intro of new variants were:

1) domestic animals or livestock animals in a southern boarder state
2) dogs
3) mammal with history of international travel within 12 months

Most important SEIs for translocation events were:

1) terrestrial mammals in the ORV zone
2) raccoon samples from west of the ORV zone
3) mammals with large or migratory home ranges 4) domestic animals with travel history within 6 months crossing variant territory boundaries

Most important SEIs for host shift events were

1) foxes
2) mammals in a nonterrestrial mammal reservoir area

Most important SEIs for identifying unusual rabies incidences were:

1) all rodents
2) cluster events (>2) in a livestock herd within 60 days
3) Other (when states wished to submit based on novelty of the case)

Conclusions: Public health officials should focus their rabies virus investigations by using specimens of epizoological importance that are appropriate.

Question 28

What species is the natural host for Hendra virus in Australia?

Which species are primary reservoir hosts?

Was urine/urogenital swab more or less likely to be positive vs serum for Hendra PCR?

Answer 28

PHYSIOLOGIC BIOMARKERS AND HENDRA VIRUS INFECTION IN AUSTRALIAN BLACK FLYING FOXES (PTEROPUS ALECTO).

McMichael L, Edson D, Mayer D, Broos A, Kopp S, Meers J, Field H.

J Wildl Dis. 2017 Jan;53(1):111-120.

Background

Flying foxes (genus Pteropus) are the natural host for Hendra virus in Australia

Black flying foxes and spectacled flying foxes are primary reservoir hosts

Henipaviruses (like Hendra virus) are thought to have coevolved with bats

Key Points:

Urine or urogenital swab (n=27) was more likely to be positive than serum for Hendra virus PCR (n=3)

All mean CBC/chem values were within reference ranges

Bats positive for Hendra virus had:

Higher lymphocyte percentage, ALP, urine protein

Lower neutrophil percentage and triglyceride levels

Unable to differentiate positive and negative bats, except for a right-shifted leukogram trend in females for both seasons and males in the summer.

No association between Hendra virus infection and biomarkers that was consistent with nutritional stress, extreme metabolic demand, or reproductive stress.

Conclusions: Hendra virus does not routinely cause over disease (as measured by CBC/chem/urinalysis) in black flying foxes.

Question 29

What is the causative agent of white nose syndrome?

Lesions assocciated?

Options for diagnosis?

Answer 29

PREVALENCE AND DISTRIBUTION OF PSEUDOGYMNOASCUS DESTRUCTANS IN MICHIGAN BATS SUBMITTED FOR RABIES SURVEILLANCE

Darling SL, Lim A, Melotti JR, O’Brien DJ, Bolin SR.

J Wildl Dis. 2017 Jul;53(3):482-490.

Background:

White-nose syndrome (WNS) is caused by Pseudogymnoascus destructans

Psychrophilic (“cold-loving”) fungus

Affects entire hibernacula during cool season of hibernation

Some bats can clear the infection during warmer ambient temperatures

P. destructans attacks wing and muzzle of hibernating bats, altering behavior and metabolism

Depletes fat stores

Wing membrane necrosis and loss

WNS epidemic causing mass mortality in 12 species of North American bats from 2006-2012

Michigan had been surveying cavernous hibernacula, such as little brown bats (Myotis lucifugus, MYLU)

Big brown bats (Eptesicus fuscus, EPFU) are noncavernicolous species that may be resistant to P. destructans

Key Points:

Surveyed all rabies negative bats (n=1,040) submitted to Michigan Dept of Health

Examined muzzle, wing, and tail membranes for orange-yellow fluorescence under UV light

Only three MYLU were positive and confirmed with PCR

Two EPFU were positive but not P. destructans positive on PCR

PCR for P. destructans run on fluorescent skin samples or plagiopatagium, if no fluorescence

Five PCR positive MYLU (three had fluorescence)

Four PCR positive EPFU harbored other species of Pseudogymnoascus, not P. destructans

All P. destructans positive bats were collected in spring (Apr-May)

In this study, 60% of bats PCR positive also had fluorescence under UV, compared to 96% in another study

EPFU appears to be more resistant to P. destructans

Not simply sampling error in cavernous hibernacula-focused studies

Lower metabolic rate and passive rewarming during hibernation

Hibernate singly instead of clustered and in less humid environments

Conclusion: Pseudogymnoascus destructans is detectable via PCR and fluorescence under UV light, though false positives are possible with current methods. Brown bats appear more resistant to WNS when compared to little brown bats.

Question 30

How did metabolic rate for Pd infected bats after hibernation vs uninfected bats months later? Difference in reproductive success?

Answer 30

BATS RECOVERING FROM WHITE-NOSE SYNDROME ELEVATE METABOLIC RATE DURING WING HEALING IN SPRING

Meierhofer MB, Johnson JS, Field KA, Lumadue SS, Kurta A, Kath JA, Reeder DM.

JWD 2018; 54(3):480-490

Background:

White-nose syndrome: disease of hibernating bats caused by Pseudogymnoascus destructans

Pd is a cold-adapted fungus that invades and damages cutaneous tissue especially wings

Has devastated populations of hibernating bats in E North America, especially little brown myotis

Previous study showed WNS causes too-frequent hibernation arousals and depletes fat reserves

Key Points:

Pd bats had more wing damage at 19d post-hibernation than controls, but no difference at day 33

In both groups wing damage increased between days 19 and 33

No differences between sex, hibernation temp, or inoculation dose

Pd infected bats had higher metabolic rate after hibernation compared to Pd uninfected bats months later

Hibernation temp, sex, inoculation dose didn’t matter

Reproductive success = number of assessed in relation to number of adult F in cage

No differences in reproductive rate between Pd and control bats, though fewer Pd bats gave birth

Conclusion: WNS little brown myotis bats had more wing damage initially after hibernation, but after some time, both WNS and control bats had wing damage; WNS bats had higher metabolic rates after hibernation compared to controls, but no difference in reproductive success.

Question 31

How does the prevalence of Pseydogymnoascus destructans change with season (winter hibernation vs spring emergence)?

Answer 31

Dispersal hazards of Pseudogymnoascus destructans by bats and human activity at hibernacula in summer.

Ballmann AE, Torkelson MR, Bohuski EA, Russell RE, Blehert DS.

Journal of Wildlife Diseases. 2017 Oct;53(4):725-35.

Background:

Prevalence of Pd is highest in winter hibernaculum, but also found on bats in summer

Several sps of bats use different caves for winter and summer roosting (cross sps contamination)

Pd persists year round in hibernaculum environment

Key Points:

No bats had visible Pd lesions during the summer but several had UV fluorescence suggestive of WNS

Few bats had evidence of damage to wing membrane from prior infection

Prevalence of Pd declines following winter hibernation and spring emergence, but there is environmental persistence

Guano had a higher prevalence than wing swabs

Guano may be an important route for dispersal - likely ingest it from grooming it off of the wings.

Presence in guano may be reason for high environmental burden

Conclusions: During summer, Pd can be spread in guano, from bats with + skin swabs (but no visible lesions), and from equipment used in hibernaculum.

Question 32

What is the optimal temp range of pseudogymnoascus destructans (general)?

Survival outside of temp range? Bat fur vs brain-heart agar vs guano

On which medium was survival highest?

Answer 32

Long-term survival of Pseudogymnoascus destructans at elevated temperatures.

Campbell LJ, Walsh DP, Blehert DS, Lorch JM.

Journal of Wildlife Diseases. 2020 Apr;56(2):278-87.

Background:

White nose syndrome (WNS)- cutaneous fungal disease causing catastrophic declines of bats

First detected in NY in 2006, believed to have come from Europe

During hibernation- PD proliferates causing damage to dermal tissue and growth around muzzle.

Die b/c of increased arousal during hibernation

PD- psychorophilic fungus w/ optimal thermal range 12-15 C, with cessation of growth at 20C

Sporulation positively correlate with humidity (up to 85%)

Persist in sediment of hibernacula w/o bats for at least 2 years

Key Points:

PD can survive extended periods of time when exposed to temps outside of thermal growth range.

Survived at least 15 days incubated at 37 C, 30 days at 30 C, 150 days at 24 C

Survival was highest on the brain-heart agar infused with sheep’s blood

Bat fur- survived at 5 days at 37 C, 60 days at 30 C, and 180 days at 24 C

Fecal material was positive for fungus 10X more frequently than skin (previous study)

Bat guano may be the source of PD b/c may be able to survive transit time

Conclusions: PD can survive above optimal temp zone (20 C), most likely bats spreading to other hibernacula

Question 33

Treatment for livingstones fruit bats with dilated cardiomyopathy?

Answer 33

MEDICAL MANAGEMENT OF DILATED CARDIOMYOPATHY IN LIVINGSTONE FRUIT BATS (PTEROPUS LIVINGSTONII)

Rowena Killick, Alberto Rodriguez Barbon, Michelle Barrows, Andrew Routh, Richard Saunders, Charlotte Day, P G Cert Exotic Animal Studies, Adam Naylor, Nicolette Hayward, David Sewell, Kieran Borgeat, Aimee L Drane, Lois Wilkie

Journal of Zoo and Wildlife Medicine 48(4): 1077–1080, 2017

Background:

In dogs with dilated cardiomyopathy, pimobendan has delayed the onset of CHF or death in some breeds

The standard of treatment for DCM in is furosemide, pimobendan, angiotensin-converting-enzyme inhibitors (ACEI)

DCM in flying fox sps has been reported to idiopathic and related to hypovitaminosis E

Key Points:

Signs of DCM in bats = lethargy, reluctance to fly, heart murmur, pale mucous membranes, tachyarrhythmia, anorexia, cachexia, cranial edema, hepatomegaly, hypothermia, and abortion

Radiographs showed cardiomegaly, dorsal deviation of the trachea, and pulmonary edema, hepatomegaly, ascites

DCM diagnosed with echocardiogram = thinning of L (+/-R) ventricular free wall, increased LV diameter, increased LA size, poor contractility, pleural effusion, hepatomegaly, ascites, tricuspid and mitral valve regurgitation

Treatment protocol for 10 bats with DCM = Furosemide +/- spironolactone + Imidapril (ACEI) +/- pimobendan

Most bats’ clinical signs improved within hours to days

One bat incidentally diagnosed with DCM has been maintained on pimobendan without developing clinical signs

Conclusions: Dilated cardiomyopathy has been diagnosed and medically managed in fruit bats.

Question 34

Anatomical features of eyes in bats?

Risk factors for ddevelopment of cataracts?

How does IOP change if bats are upside down vs upright

Answer 34

SELECTED OPHTHALMIC PARAMETERS AND POTENTIAL RISK FOR LIGHT-INDUCED CATARACTS IN TWO COLONIES OF CAPTIVE INDIAN FLYING FOXES (PTEROPUS GIGANTEUS)

Peter M DiGeronimo, Simone R R Pisano, Nicola Di Girolamo, Carl F Spielvogel, Gordon J Pirie, Rene Carter

J Zoo Wildl Med, 49 (1), 129-133 Mar 2018

Background:

Indian flying foxes are crepuscular foragers of fruit and do no echolocate

Bat ocular anatomical features:

Avascular retina without a fovea

Low cone:rod ratio

Spectral cone type that gives dichromatic UV vision

More developed retinotectal (from retina to midbrain) and retinofugal (from retina to brainstem) pathways

Exposure to high intensity fluorescent lighting is a risk factor for development of cataracts in captive penguins

Increased exposure to natural UV light is a risk factor for development of cataracts in pinnipeds

Increased exposure to natural UV light is risk factor for both cataracts and corneal disease in humans and dolphins

Key Points:

When bats were moved from natural lighting to >12 h/day fluorescent lighting, the prevalence of cataracts increased from 0% to 55%

Risk of having cataracts was 18x greater in quarantine bats

All lesions were bilateral

Many bats in both enclosures had iridal collarettes (normal variation)

Weight was affected by housing and ocular pathology: exhibit bats > quarantine bats > quarantine bats with cataracts

IOP was higher in upside down bats than upright, which is similar to findings in other bat species

Conclusions: Indian flying foxes (like other animals adapted to low natural, ambient light) are susceptible to the development of ocular disease when exposed to fluorescent lighting.

Question 35

Mechanism of toxicity of carbamates? Treatment?

What tissue should be used for diagnostic testing in bats?

Answer 35

SUSPECTED CARBARYL TOXICITY IN A CAPTIVE COLONY OF STRAW-COLORED FRUIT BATS ( EIDOLON HELVUM).

Selig M, Lewandowski A.

J Zoo Wildl Med. 2017 Dec;48(4):1247-1249.

Background:

Carbamates: popular insecticides with generally rare toxic effects

Inhibit acetylcholinesterase, which causes constant postsynaptic activation

Antagonized with atropine

Carbamate toxicity = hypersalivation, gastrointestinal hypermotility, vomiting, cramping, diarrhea, dyspnea, cyanosis, miosis, muscle fasciculations, convulsion, paralysis, and death

Permethrin toxicity has similar clinical signs

Key Points:

Group of bats developed hypersalivation, miosis, and death after being fed unknowingly carbaryl-contaminated ficus

Less severe bats recovered with atropine, dextrose, fluids, and activated charcoal

Cholinesterase activity was < 50% healthy bats in whole blood and retinal tissues

No decrease in brain tissue submitted, but toxin does not always cross the blood-brain barrier

Conclusion: Fruit bats may be sensitive to carbamate toxicity and can be treated with atropine. Use whole blood or retinal tissue to test for cholinesterase levels.

Question 36

Which castration technique had a higher complication rate in bats? Surgical ligation or radiosurgery? Which had a higher mortality rate?

Answer 36

Surgical orchiectomy in fruit bats—description of two techniques in the ruwenzori long-haired fruit bat (rousettus lanosus) and the jamaican fruit-eating bat (artibeus jamaicensis)

Prud’homme Y, Ferrell ST, Couture ÉL, Marquet B, Desmarchelier M.

Journal of Zoo and Wildlife Medicine. 2020 Jun;51(2):297-302.

Bat male testes location varies (abdominal, inguinal, scrotal, or mobile)

Surgery is easier during breeding season when testes are enlarged

Surgical ligation had a higher complication rate (6.7%, all prolonged recovery from anesthesia)

Radiosurgery was faster than ligation

Had a lower complication rate (but incl. Dyspnea, hemorrhage, prolonged rovery)

Higher mortality rate (1.6%)

Vasectomy has an advantage of controlling reproduction without altering hormone production and harem behavior

Conclusions: You can castrate a bat with traditional ligation or radiosurgery

Question 37

Bats generally have a higher level of what chemistry enzyme compared to other mammals?

General concentration of bat urine?

Which sex was observed to have ketonuria?

Answer 37

HEMATOLOGY, PLASMA BIOCHEMISTRY, AND URINALYSIS OF FREE-RANGING GREY-HEADED FLYING FOXES ( PTEROPUS POLIOCEPHALUS) IN AUSTRALIA.

Edson D, Field H, McMichael L, Mayer D, Martin J, Welbergen J, McLaughlin A, Huth L, Kristoffersen J, Tsoukalas G, Kirkland P.

J Zoo Wildl Med. 2018 Sep;49(3):591-598.

Background:

Grey-headed flying fox (GHFF) are nectivorous and frugivorous bats that are native to Australia

Key Points:

ALP was higher than most other mammals in all groups (adult mean ~600)

Consistent with other bat species

Many bats (54%) were hyposthenuric or isosthenuric

Consistent with their high dietary water intake

Males GHFF had ketonuria

Similar to other bat species in this genus

Adults had higher MCV, MCVC, BUN, Cr, tBili, ALT, TP, GLob, USG

Subadults had higher WBC, lymphocytes, and monocytes

Juveniles had higher neutrophils

Males had higher ALT and glucose

Females had higher mean TWBC, lymphocytes, and monocytes

Conclusions: Clinically normal grey-headed flying foxes may have an elevated ALP (compared to other mammals) and hyposthenuria/isosthenuria, and males may normally have ketonuria.

Question 38

General urine specific gravity for egyptian fruit bats? How does this differ from other species?

Answer 38

REFRACTOMETRIC URINE SPECIFIC GRAVITY OF FREE-LIVING EGYPTIAN FRUIT BATS (ROUSETTUS AEGYPTIACUS).

Eshar D, Lapid R, Weinberg M, King R, Pohlman LM.

J Zoo Wildl Med. 2017 Sep;48(3):878-881.

Background:

It is thought that frugivorous bats (like Egyptian fruit bats) cannot concentrate their urine

Flying foxes = lower USG with 24% isostheuric based on dogs (1.008-1.012)

Urine osmolality, osmolarity and specific gravity can assess ability of renal tubules to concentrate

USG increases with increasing solute concentrations but is dependent on particle #, size, and weight

Refractometry = indirect expression of USG by measurement of urine refractive index

Ratio of velocity of light in air to velocity of light in solution; a change in velocity deviates the path of light and is proportional to # and type of particles dissolved in urine

Key Points:

USG: 1.030 (1.006 – 1.050) suggests ability of this spp. to concentrate urine

No sex difference

Only 4% within isosthenuric interval = this species can concentrate its urine

Mean urine concentrations: 600 mOsm frugivorous, 1600 non-frugivorous, 3200 insectivorous and 4700 vampire

Differences are most related to physiological renal adaptation to different dietary preferences

Ex. Mass of renal medulla is decreased, cortex is increased in frugivorous bats

Conclusions: Reports USG values in apparently healthy free-living Egyptian fruit bats, suggesting that this frugivorous species is able to highly concentrate its urine.

Question 39

What sites can be used for arterial blood pressure measurements in flying foxes?

What was a common complication?

How did blood pressure in bats with structural heart dz differ from healthy bats?

Was BP different in dorsal vs inverted body position?

Answer 39

A DESCRIPTION OF ARTERIAL BLOOD PRESSURE MEASUREMENT IN TWO SPECIES OF FLYING FOXES (PTEROPUS VAMPYRUS AND PTEROPUS HYPOMELANUS)

Gatson BJ, Paranjape V, Wellehan JF, Bailey K.

Journal of Zoo and Wildlife Medicine. 2019 Sep;50(3):665-71.

Method for invasive blood pressure monitoring in bats = 24 g x 1” catheter in median or posterior tibial artery

Median artery = distal ⅔ ofl humerus

Posterior tibial artery = along tibia

Hypothermia was a common complication

Bats with structural heart disease had lower mean arterial blood pressures than healthy bats

Blood pressure not different in dorsal vs. inverted positions

Conclusions: Arterial catheterization can measure direct blood pressure in flying foxes and found lower MAP in those with heart disease.

Question 40

PK of oral meloxicam in malayan flying foxes? Any adverse effects?

Answer 40

PHARMACOKINETICS OF MELOXICAM FOLLOWING A SINGLE ORAL DOSE IN MALAYAN FLYING FOXES (PTEROPUS VAMPYRUS).

Goodnight AL, Cox S.

J Zoo Wildl Med. 2018 Jun;49(2):307-314.

Background:

Painful conditions commonly presented in bats include skeletal fluorosis, trauma, osteoarthritis, and surgery

The researchers and others have used a 0.2 mg/kg dose PO q24h without adverse effects

This study gave 0.2 mg/kg PO once, which the bats happily licked out of jelly-coated syringes

Venipuncture in awake animals from the brachial vein or artery at 3 timepoints for each bat in the first 8 hours

Note: many of the bats developed severe hematomas even with sustained manual pressure

May have fixed the problem by decreasing the temperature in the enclosure by 6 degrees F?

Key Points:

No adverse clinical effects

More rapid absorption than in dogs, humans, and bottlenose dolphins

t1/2: measurement of the time for the drug to lose half of its pharmacologic activity

Short half life was similar to Caribbean flamingos and Cape Griffon vultures

Amazon parrots had a longer elimination time

Plasma concentrations were above “therapeutic” levels for less than 5 hours

Meloxicam is often protein bound and concentrates in regions of inflammation, so may have a longer duration

Conclusions: Malayan flying foxes are able to rapidly absorb and eliminate meloxicam.

Question 41

Mechanism of terbinafine?

General pharmacokinetics of terbinafine in little brown bats?

Answer 41

Pharmacokinetics of terbinafine in little brown myotis (Myotis lucifugus) infected with Pseudogymnoascus destructans.

Court MH, Robbins AH, Whitford AM, Beck EV, Tseng FS, Reeder DM.

American journal of veterinary research. 2017 Jan;78(1):90-9.

Background:

Mechanism by which it causes death: increased energy expenditure, loss of water and electrolytes, and inadequate immune response.

Terbinafine is an allylamine antifungal agent that is cidal and static

Static: inhibits ergosterol synthesis (ergosterol is made from squalene)

Cidal: accumulation of squalene is toxic to cells

Has wide tissue distribution including hair and skin, persists in tissue

Terbinafine has fewer and milder side effects (GI upset) than azoles

Key Points:

Longer ½ life of terbinafine observed in this study (compared to some other animals)

Could be secondary to the slower metabolism as bats were maintained in a state of torpor

Positive correlation between the terbinafine in hair, skin, and wing

Hair terbinafine concentration could be used as a proxy for skin and wing concentration

Able to reach MIC in 60mg/kg group for 30 days; in 20mg/kg group 6 days; 6mg/kg group (1 day)

May need sustained release implants to provide MIC levels for long enough to kill slow growing Pd

Conclusions: Terbinafine doses between 6-60mg/kg x10 days may be tolerated by bats to kill Pd. There is a dose dependent curve for terbinafine, higher doses persist longer in tissues (plateaus at about 60mg/kg).

Question 42

Most common reservoir of human and animal rabies in Latin America?

Most common cause of rabies in Canada and US?

How did IM vs oral dosing of ERA-G333 vaccine affect big brown bats?

Answer 42

Gilbert, A. T., Wu, X., Jackson, F. R., Franka, R., McCracken, G. F., & Rupprecht, C. E. (2020).
Safety, immunogenicity, and efficacy of intramuscular and oral delivery of ERA-G333 recombinant rabies virus vaccine to big brown bats (Eptesicus fuscus).
Journal of wildlife diseases, 56(3), 620-630.

Background:
* Rabies = lyssavirus
* Vampire bat = most common reservoir of human and animal rabies in Latin America
* Insectivorous bats = most common cause of rabies in Canada and US
* Spillover from wild carnivores is less important
* Evelyn-Rotiniki-Abelseth (ERA) strain of rabies is attenuated and used for oral rabies vaccination of carnivores
* ERA-G333 vaccine has glycoproteins at position 333 to reduce chance of bad mutations
* Used in non-human primates, red foxes, gray foxes, racoon dogs, domestic dogs

Key Points:
* After IM injection of ERA-G333, big brown bats seroconverted and were protected against rabies challenge
* Oral dose of ERA-G333, did not cause any immune response nor protection
* ERA-G333 did not cause rabies on its own in the bats

Conclusions: ERA-G333 rabie vaccines worked when given IM but not PO.

Question 43

What was found to be a significant cause of death in bent-winged bats?

Answer 43

Holz, P. H., Stent, A., Lumsden, L. F., & Hufschmid, J. (2020). Trauma found to be a significant cause of death in a pathological investigation of bent-winged bats (miniopterus orianae). Journal of Zoo and Wildlife Medicine, 50(4), 966-971.

Abstract: Determining the causes of mortality in endangered species is essential to understanding the possible reasons behind their decline and to facilitating the implementation of mitigating steps. The southern bent-winged bat (Miniopterus orianae bassanii) is a critically endangered Australian bat whose population numbers have decreased over the past 50 years. As part of a larger investigation to determine if disease could be a contributing factor to the decline, 27 southern bent-winged bats and one closely related eastern bent-winged bat (Miniopterus orianae oceanensis) that died during the study were necropsied and examined histologically. Trauma was the most common cause of death in the southern bent-winged bats, which mostly occurred at one site where fencing and other infrastructure was positioned around a key breeding cave. In response to these findings, management actions have been implemented to reduce this infrastructure-associated mortality of southern bent-winged bats. The single eastern bent-winged bat examined had a severe dermatitis caused by the mite Notoedres muris.

• 10 cases (71% of adults) trauma, 13 unweaned pups (2 had infections).
• Echolocation system of bats has difficulty detecting smooth vertical surfaces
• Mortality rate of pups 10% per year in bent-winged bats
• Bats typically carry mites of genus Spinturnix which do not cause clinical signs. Notoedres muris has not previously been reported in bats

Question 44

Was more atelectasis observed in a vertical position or inverted position for bats with CT?

Answer 44

Hostnik, E. T., Adkesson, M. J., & Ivančić, M. (2020). Computed tomography lung volume differs between vertical and inverted positioning for egyptian fruit bats (rousettus aegyptiacus). Journal of Zoo and Wildlife Medicine, 50(4), 897-902.

Less atelectasis was observed in vertical position compared to inverted. Recommend during anesthesia and recovery.

Question 45

Main spp of rabies transmission in Latin America? Eastern US? Western US?

What is the predominant reservoir globally?

Answer 45

Journal of Wildlife Diseases, 57(2), 2021, pp. 303–312

RELATEDNESS AND GENETIC STRUCTURE OF BIG BROWN BAT (EPTESICUS FUSCUS) MATERNITY COLONIES IN AN URBANWILDLAND INTERFACE WITH PERIODIC RABIES VIRUS OUTBREAKS

Faith M. Walker, Colin J. Sobek, Camille E. Platts-McPharlin, and Carol L. Chambers – reviewed by MSM

Abstract: Big brown bats (Eptesicus fuscus) are the bat species in North America most frequently found to be rabid because of their high rate of human contact and thus submissions for rabies testing, of which, 4–5% are positive. The social behavior of big brown bats during the summer months may drive space use and potential viral exposure to conspecifics and mesocarnivores. We collected 88 unique genetic samples via buccal swabs from big brown bats captured at four maternity roosts surrounding a golf course during the summer of 2013. We used seven microsatellite loci to estimate genetic relatedness among individuals and genetic structure within and among colonies to infer whether females selected roosts based on kinship and used genetics and radio telemetry to determine the frequency of roost switching. We found roost switching through genetics and telemetry, and no evidence of elevated genetic relatedness within colonies or genetic structure among colonies. Social cohesion based on relatedness may not act to constrain the pathogen to a particular roost area, and thus, geographic mobility may increase viral exposure of bats in neighboring areas.

Key Points:

· Rabies – highest fatality rate of infectious diseases (tens of thousands of human deaths annually)

o Dogs are predominant reservoir globally

o In the Americas (with good domestic & mesocarnivore vaccination), most cases are from bats

· Main species of transmission

o Latin America – common vampire bat (Desmodus rotundus)

o Eastern US – silver-haired bat (Lasionycterius noctivagans) and tri-colored bats (Perimyotis subflavus)

o Western US – big brown bats (Eptesicus fuscus) – roost in manmade structures, large distribution

o Bats in southwest US more likely to be rabid – Arizona is there at the top

· This study aimed to describe the dispersion of BBB in Arizona, hypothesizing that bats may preferentially roost with related animals, limiting the spread of rabies

· No preference for relatedness in roost selection occurred

Take Home: Big brown bats disperse and use multiple roosts, making the spread of rabies easier

Question 46

A recent study examined the efficacy of the anti-GnRH immunotherapeutic product Improvest in large flying foxes.

What was the objective of the study? What was measured?

What were some of the side effects of the injection?

How were these side effects managed/

How did the measured hormone levels change with the injection?

What behaviors changed as a result?

Answer 46

AJVR 2023 84(2)
Outcomes from an anti-gonadotropin-releasing hormone immunotherapeutic trial in large flying foxes (Pteropus vampyrus)

Abstract:
OBJECTIVE The anti-GnRH immunotherapeutic product Improvest was administered to intact male large flying foxes (Pteropus vampyrus) under managed care for androgen mitigation, leading to a decrease in agonistic behaviors, falls, and injuries from conspecific attention.
ANIMALS 12 males were included in this study.
PROCEDURES Eleven bats received subcutaneous (SC) Improvest interscapular, and 1 animal received Improvest SC in its leg. Assessments included clinical presentation, treatment, behavior, and urine and fecal glucocorticoid metabolites and testosterone (T5) concentrations.
RESULTS **Eleven of the 12 bats developed reactions, which included facial edema, localized irritation, swelling of the head and neck, and pruritus with varying degrees of skin ulceration and subsequent necrosis. Three of the animals required extensive treatments, and the 1 animal who received the injection in its leg was unaffected. Posttreatment, fecal glucocorticoid metabolite and/or T5 values were at or below the nonbreeding season baseline for 3 successive breeding seasons, and there was a reduction in agonistic interactions, falls, and injuries. **
CLINICAL RELEVANCE A behavioral characteristic of this species is to focus on areas of irritation that exacerbated the extent of the skin wounds. Some cases required medical, surgical, and behavioral intervention. Large flying foxes may be particularly sensitive to this immunotherapeutic when given subcutaneously in the interscapular region. Despite this reaction, the positive long-term effects on behavior and multiyear reduction of hormones suggest that the use of this immunotherapeutic warrants further investigation, although the results should be taken into consideration with other factors such as handling, treatments, chronicity of lesions.

Intro
* Large flying foxes (Pteropus vampyrus) have complex social structures and colonies are normally harems of 1 male and several females
* Males defend their territories and display behaviors such as chasing, biting, hooking, and wing flexing at incoming males.
* The objective of the present study was to assess the effectiveness of this immunotherapeutic at suppressing T5 and leading to a decrease in agonistic behaviors, falls, and injuries in a colony of male large flying foxes under managed care.

M&M
* 12 MI large flying foxes implanted with GnRH agonist Improvest SQ interscapular
* Monitored effect on behavior as well as testosterone (T5) and fecal glucocorticoid metabolite (FGM) levels

Results
* At 24 hours postinjection, all animals, except 1 were anorexic and depressed and later developed signs of pruritus in the area of the injection site
* The entire colony was treated with an antihistamine
* At 96 hours, 1 animal still had not improved behaviorally and was treated with fluids, dexamethasone and cerenia
* One month postimmunotherapeutic, with continued self-trauma, the entire colony was placed on prednisone and ranitidine
* Excisional and/or punch biopsies from affected regions of 3 most affected individuals were characterized by the presence of extensive deep dermal and hypodermal coagulative necrosis and variably extensive epidermal ulceration and necrosis.
* The presence of the adjuvant was not documented within macrophages.
* Posttreatment, fecal glucocorticoid metabolite and/or T5 values were at or below the nonbreeding season baseline
* Also a significant reduction in agonistic interactions, falls, and injuries

Discussion
* Large flying foxes that received an interscapular subcutaneous Improvest immunotherapeutic developed injection site reactions ranging in severity from pruritus to ulceration with tissue necrosis requiring surgical debridement.
* The 1 animal that was administered the injection in the leg did not develop similar adverse effects.
* Anatomical location with its complex accessory structures of glands and species predilection for self-mutilation (over-grooming) likely resulted in the case presentations
* interscapular space may not be the ideal location for subcutaneous injections with androgen-stimulating compounds despite its ease of access.
* Also could have been a hypersensitivity to the adjuvant
* UGM and urinary T5 were elevated during the first post-GnRH immunotherapeutic treatment month compared to the pretreatment control
* FGM and T5 measurements in the first breeding season immediately post-GnRH immunotherapeutic treatment were reduced to values lower than the previous breeding season, for the 3 successive breeding seasons
* Treatments for adverse reactions were tailored to each individual case and focused on behavioral, topical, and systemic management;

Question 47

A recent study investigated the environments of bridges and roadside culverts (drainage pipes) as potential pathogen transmission corridors for white nose syndrome in bats.

What is the pathogen associated with WNS?

what is the ideal range for growth of this fungus?

What was the temperature of these roadside culverts in Gerogia throughout the year?

Answer 47

JWD 2022 58(2):322-332
Roadway-associated culverts may serve as a transmission corridor for Pseudogymnoascus destructans and white-nose syndrome in the coastal plains and coastal region of Georgia, USA
Lutsch KE, McDonald AG, Gabriel KT, Cornelison CT

ABSTRACT: White-nose syndrome (WNS) is a disease among hibernating North American bats caused by the psychrophilic fungus Pseudogymnoascus destructans. Since its discovery in New York state, US, in 2006, and as of 2020, WNS has rapidly spread to 34 American states and seven Canadian provinces, causing precipitous declines of native bat populations across North America. The rapid spread of this fungal pathogen has been facilitated by the social behavior of bats, as well as the ability of subterranean hibernacula to support a favorable environment for P. destructans, and is probably exacerbated by anthropogenic transmission events. Although many bat species roost in natural cave environments, bats also selectively use diverse structures for hibernacula. Certain areas of the US lack caves, forcing bats to select different winter roosting environments. Bats have been observed using roadway-associated structures, such as bridges and culverts, for roosting, especially in regions that lack natural cave environments. However, the potential for P. destructans transmission in such roadway-associated structures requires further investigation. Understanding potential pathogen transmission in these widely used anthropogenic structures is crucial to disease management and preventing further declines of imperiled bat populations. Our study investigated these structures as potential pathogen transmission corridors by surveying the use of these structures by Perimyotis subflavus and other susceptible bat populations and by measuring their temperature. The results suggest the environments of roadway-associated culverts are thermally conducive to the proliferation of P. destructans-even in regions with mild winters-and the development of WNS in susceptible bat populations. It is apparent these roadway-associated structures have the potential to spread P. destructans and exacerbate the effect of WNS on susceptible bat populations.

Key Points:
* Pseudogymnoascus destructans: psychrophilic ascomycete responsible for white-nose syndrome
o Able to grow between 0 C and 20 C, with an optimal growth range of 12.5–15.8 C
o Transmitted through bat-to-bat, bat-to-substrate, or human-mediated transmission
* Temperatures within roadway-associated culverts fell within the growth range of P. destructans
o Potential for fungal growth and host infection during almost half of a calendar year
o Almost 2 months saw temp within the optimal range for P. destructans growth
* Disease severity could also be exacerbated because of the previously unreported clustering behavior observed in tricolored bats (P. subflavus) roosting under these conditions

TLDR: Roadway-associated culverts in the southern region of Georgia can provide a suitable environment for the survival and proliferation of P. destructans

Question 48

A recent study described the morbidity and mortality of Livingstone’s fruit bat.

What is the scientific name of this species?

What were the most common morbidities in this species?

Older animals were more likely to suffer from what morbidities?

Males were more likely to suffer from what morbidities?

What was the most common cause of death?

What was the second most common cause of death?

Answer 48

JZAR 2022 10(3):149-57
Mortality and morbidity in captive Livingstone’s fruit bats Pteropus livingstonii
Segura-Cortijos C, Bell E, Routh A et al

ABSTRACT: Medical and pathology records were reviewed for 161 Critically Endangered Livingstone’s fruit bats Pteropus livingstonii (LFBs) held at Jersey Zoo and Bristol Zoological Gardens between 1992 and 2017, representing over 95% of the historical population managed at these institutions. The association of mortality and morbidity in relation to age (immature: 0 days–2.5 years, adults: 2.5–15 years, geriatric >15 years) and sex was analysed. Overall, 427 individual medical problems were identified in 56% of the population. The most common causes of morbidity were wounds (34.9%, n=150), localised inflammation (12.9%, n=55) and fractures (10.8%, n=46). Wounds were predominantly located in patagia (25.0%, n=38) and digits of the forelimbs (22.0%, n=33), with males at greater risk than females. Immature specimens were more likely than adult and geriatric animals to suffer wounds. Localised inflammatory lesions showed an increased risk associated with age. Females were found to be more likely to suffer from fractures. Eighty-eight deaths were recorded; the most common identified causes of mortality were early foetal death (18.2%, n=16), heart diseases (14.8%, n=13) and conspecific aggression (10.2%, n=9). Males and geriatric animals had a greater risk of suffering cardiac disease. This study determines the most common medical problems encountered in LFBs in captivity and establishes grounds for additional research into specific pathologies in this species.

Background:
- Livingstone’s fruit bat = critically endangered species endemic to the Republic of the Comoros
– Captive population established between 1992-1995 with only 17 (10 males, 7 females)
– Most of the current captive population is held at the Jersey Zoo and Bristol Zoo

Key Points:
- Wounds were the most common morbidity
– Most wounds identified on patagium > digits of the forelimbs&raquo_space; head injuries
– More likely to occur in immature and male bats
– Presumed due to intraspecific aggression
- Localised inflammation was frequently observed
– Mostly seen on digits, primarily forelimb digit 1 distal phalanx/claw ankylosis
– Geriatric animals were more likely to suffer from such ankylosis
- Frequent skin diseases included dermatitis and onychopathies
– Pinna most frequently affected by dermatitis
– Onychopathies mainly affected forelimb digits, esp. digit 1
– Males more likely to be diagnosed with dermatitis
- Fractures, arthritis and luxation were significant contributors to morbidity
– Fractures mostly affected forelimb, esp. digits
– Less likely in captive-born bats & adult females
– Etiology likely in-flight crashes or falls
– Luxations observed equally in fore and hindlimbs, coxofemoral joint most affected
– Arthritis most often observed in hindlimbs, esp. digits and stifles
– Geriatric animals were more likely to have arthritis
- Dental abnormalities were a common incidental finding
– Example: periodontal abscess, tooth fx, tooth loss, tooth wear & congenital malocclusion
– Geriatrics and females more likely to present with dental issues
- Early fetal death most common COD
– Often due to an undetermined cause
– Small founder population may have resulted in inbreeding within the captive population
– Dietary deficiencies need to be evaluated as a potential underlying cause too
- Heart disease were the second most significant COD esp. in adult and geriatric animals
– Males were more likely to die from heart diseases
– DCM described in bats associated with hypovitaminosis E and of unknown etiologies
- Infectious disease and neoplasia relatively uncommon

TLDR: Most common causes of morbidity were wounds, localised inflammation, and fractures. Most common causes of mortality were early foetal death, heart diseases, and conspecific aggression

Question 49

A recent study described the neoplasms of a managed populatino of Jamaican fruit bats.

What is the scientific name of this species?

What tumor types were observed?

Was any tumor type more commonly observed?

Answer 49

JZWM 2022 53(3) 583-592
A REVIEW OF NEOPLASMS IN A POPULATION OF JAMAICAN FRUIT BATS (ARTIBEUS JAMAICENSIS) UNDER HUMAN CARE

Abstract
Although reports of tumors in chiropteran species are rare, postmortem examinations conducted on aging captive populations suggest that neoplasia may be more prevalent and clinically more significant contributors to morbidity and mortality than previously appreciated in these animals. A retrospective study was conducted to describe cases of neoplasia identified in Jamaican fruit bats (Artibeus jamaicensis) under human care at the Vancouver Aquarium between 01 January 2013 and 31 March 2021. Approximately 13.2% (N = 47/355) of the bat population died within this time span, and gross and histologic postmortem examinations were performed on 28 of 47 individuals. There were eight malignant and three benign neoplasms detected in 10 cases (eight females, two males), including: malignant histiocytoma, esophageal adenocarcinoma, two squamous cell carcinomas, spindle cell sarcoma, periosteal chondrosarcoma, uncharacterized uterine neoplasia with unrelated multicentric pulmonary carcinoma, and cholangiocarcinoma. Benign variants included three suspected uterine leiomyomas. A wide variety of tumor types and tissue predilections were identified, suggesting a complex and perhaps multifactorial pathogenesis in neoplastic transformation in microchiropterans. To the authors’ knowledge, these tumor types have not been previously described in Artibeus sp., and some of these neoplasms have not previously been reported in chiropterans.

Key Points
* Indoor population, mixed sex, of Jamaican or common fruit bats
* Age at death 5-10 yr or unknown adult age
* 10 cases of neoplasia with full necropsies reported - see abstract for the list of tumor types
* Presented as a mass antemortem (malignant histiocytoma [cranial thorax], spindle cell sarcoma [neck/scapula] ), found dead (esophageal adenocarcinoma, pericardial SCC), found moribund (periosteal chondrosarcoma), exophthalmia (SCC), acute hemoperitoneum (Cholangiocellular carcinoma)
* 3 cases of uncharacterized uterine neoplasia - age 5-10 yrs, presented with acute perineal subcutaneous edema, constipation, rectal prolapse, immobile R hindlimb or found dead - all diagnosed on necropsy

Take home message
* Aged Jamaican fruit bats can get a variety of neoplasms, both benign and malignant. All benign neoplasms were uterine leiomyomas.

Question 50

A recent case series described complications associated with absorbable gelatin hemostatic sponges during liver biopsy in Egyptian fruit bats.

What is the scientific name of this species?

Why were the liver biopsies being performed in the first place?

What side effects of these sponges have been observed in other species?

List three potential adverse effects that occurred with the use of these sponges in this species?

What was the recommendation for their future use?

Answer 50

Hepatic to pulmonary embolism of absorbable gelatin hemostatic sponge in two egyptian fruit bats (Rousettus aegyptiacus).
Pastor AR, Stasiak I, Nielsen AM, Smith DA.
Journal of Zoo and Wildlife Medicine. 2022;53(3):628-631.

In a study on iron regulation, liver biopsies were collected at two time points from 34 adult Egyptian fruit bats (Rousettus aegyptiacus). An absorbable gelatin hemostatic sponge (GS) was inserted at biopsy sites for local hemostasis in 16 bats. In the subsequent 10 yr, 12 of these bats died or were euthanized, and 11 were examined histologically; in 2 bats, intravascular GS was identified in the lungs and in 1 bat, unabsorbed GS was also identified at the hepatic biopsy site. The remaining hepatic GS was associated with local abscessation and intralesional bacteria and fungi and remained at the hepatic biopsy site for a prolonged period after placement (1 yr). The findings of local hepatic abscessation and GS embolization in the lungs of these two bats highlights a potential adverse effect related to its use in zoologic species.

Background
- Frugivorous bats - iron storage disease significant cause of M&M in captivity
- Gelatin hemostatic sponges are used for liver biopsies
– Reported side effects: fibrosis and necrosis of liver at placement site in a rabbit, foreign body reaction in a dog

Key Points
- 2 cases of pulmonary embolism from hepatic biopsy sites 1 and 3 yr later with associated abscessation in the liver and lung in 2 Egyptian fruit bats
– Amphophilic plantlike foreign material with a flaky or honeycomb appearance that stained positively with PAS
- Also saw adhesions of intestines or diaphragm to the liver biopsy sites
- Degradation of the gelatin sponge was prolonged compared to package insert (4-6wk) or did not occur at all
- Consider removal of the material prior to surgical closure once hemostasis is achieved

Question 51

A recent study investigated the prevalence of SARS-CoV 2 in North American bats.

What makes bats such competent hosts for coronaviruses?

How were these bats tested for coronaviruses?

What were their findings?

Were any positive for SARS-CoV 2?

Answer 51

Journal of Zoo and Wildlife Medicine 53(4): 811–816, 2022
SURVEILLANCE OF BATS IN THE UNITED STATES FOR SARS-COV-2 AND OTHER CORONAVIRUSES
Haley Zeliff, MES, Julie C. Ellis, MS, PhD, Greg Turner, Andrew Di Salvo, DVM, MPVM, Amanda Barnard, MS, and Eman Anis, DVM, MVSc, PhD – Rev by AJC

Abstract: Bat coronaviruses (CoVs) are extremely prevalent throughout the globe and exhibit a wide range of genetic diversity. Currently, little is known about the susceptibility of New World bats to severe acute respiratory syndrome-2 (SARS-CoV-2), the causative agent of COVID-19. Also, there is limited information about the genetic diversity of other CoVs in the New World bats. The determination of genetic diversity of bat CoVs through continuous surveillance is essential to predict and mitigate the emergence of new CoVs and their impacts on the health of both humans and animals. In this study, **491 guano specimens collected from New World bats and 37 specimens collected from Old World bats during July 2020 to July 2021 were tested for SARS-COV-2 and other CoVs using a real-time reverse transcriptase-polymerase chain reaction (RT-PCR) panel and pan-coronavirus PCR that target a highly conserved region of CoVs. No evidence of SARS-CoV-2 was found in the tested specimens. **An alpha CoV was detected in a single specimen from a big brown bat (Eptesicus fuscus). This information was used by wildlife agencies and rehabilitation facilities to permit the release of bats during the pandemic while mitigating the risk of spreading SARS-CoV-2 among North American bats and other wild animal populations

Key Points:
● Bats seen as reservoir hosts for many coronaviruses – have defect in proinflammatory response which reduces the pathology triggered by CoVs.
● SARS-CoV2 has been detected in lions, tigers, gorillas, and white-tailed deer
● Objective: investigate wild NA bats in rehab facilities and captive OW bats for SARS-CoV2 and other CoVs
● SARS-CoV2 was not detected in any of the bats guano analyzed from NW and OW bats from rehab and managed care setting à rehab were able to release overwintered bats based on these results
● No CoVs detected from OW bats in managed care
● Single big brown bat (E. fuscus) in PN tested positive for an alpha CoV, similar to other NA big brown bat alpha CoVs à same species of bats harbor closely related CoVs
○ OW bats known to harbor multitude of diverse CoVs, but NW bats are understudied but appear to have a more limited diversity of CoVs and individuals of same spp harbor similar CoVs

Take Home: No SARS-CoV2 detected in NW/OW bats. No CoV detected in OW bats in managed care. Single alpha CoV detected in a free-ranging NW bat.

Question 52

A recent study investigated the factors associated with successful rehabilitation of Big Brown Bats in Wisconsin.

What is the scientific name of this species?

What is the mite that affects this species?

What was the seasonality of successful bat rehabilitation?

What conditions had a negative correlation with successful release?

Answer 52

FACTORS IMPACTING SUCCESSFUL REHABILITATION OF BIG BROWN BATS (EPTESICUS FUSCUS) IN A WISCONSIN WILDLIFE REHABILITATION CENTER: A 5-YEAR RETROSPECTIVE.
Minor RL, Döpfer D, Lemley EM, Thurber MI.
Journal of Zoo and Wildlife Medicine. 2023 Mar;54(1):32-9.

The big brown bat (Eptesicus fuscus; EPFU) is widely distributed throughout the Americas and plays critical roles in sustaining cave ecosystems and abating agricultural pests. In Wisconsin, EPFU is a threatened species with declining populations due to hibernacula disturbances, wind turbines, and habitat destruction. Due to their ecological and economic value, it is important to be able to release EPFU that enter wildlife rehabilitation centers back to the wild. This study evaluated the medical records of 454 EPFU (275 male, 179 female) admitted to a wildlife rehabilitation center in Wisconsin from 2015 to 2020. For each bat, the season at intake, examination findings, length of time in rehabilitation, and final outcome (released or not released) were recorded. Using a multiple variable logistic regression model, there was a statistically significant positive association between length of time in the rehabilitation center and likelihood of release (odds ratio [OR] 1.08; 95% CI 1.06–1.12); this association can be explained by the need to overwinter some otherwise healthy bats in rehabilitation during hibernation. The following examination findings were associated with a significantly lower likelihood of release: wing injury (OR 0.32; 95% CI 0.10–0.89) and decreased body condition (OR 0.29; 95% CI 0.12–0.64). When corrected for time spent in rehabilitation (potentially artificially lengthened due to hibernation), patients admitted in the summer and fall were less likely to be released than those admitted in the winter (OR 0.93; 95% CI 0.90–0.96 and OR 0.95; 95% CI 0.92–0.97, respectively). The results of this study can be used to help veterinarians and licensed rehabilitators better triage EPFU during admission to wildlife rehabilitation centers in order to improve management and promote successful release back to the wild.

Background
- External parasites are primarily mites, Steatonyssus occidentalis
- One study in big brown bats found 4mm patagial biopsy took 27d to heal and 8 mm biopsy took 127d to heal, another found species differences in healing time
- One study found delayed wound healing during winter due to hibernation, low temps, and decreased dietary consumption

Key Points
- Median time in rehab was 75d
- Bats admitted in winter had highest frequency and highest percent released
– Patients admitted in summer and fall were sig less likely to be released
– Most bats admitted in winter were physically healthy and had been disturbed during torpor, vs bats admitted in summer or fall were more likely to present with injuries reducing likelihood of release
– Intake of healthy bats in winter that required overwintering with successful release in spring likely explains longer time in rehab associated with increased likelihood of release
- Positive association between length of time in rehab and likelihood of release
- Negative association between wing injury, decreased BCS and likelihood of release
- Joint swelling at initial exam did not affect likelihood of release and not all had complete resolution likely due to scarring and/or fibrosis of the joint
– Specific etiology was most often unknown, novel poxvirus has been documented in Pacific Northwest and novel Mycoplasma spp. Described with polyarthritis
– Initial findings suggest presence of joint swelling at intake should not impact decision to admit bat to rehab

Conclusions
- If a big brown bat presents to rehab with wing injuries or decreased body condition, or during summer or fall, they were less likely to be released back to the wild than bats without these factors.