Common or cotton­eared marmosets

The common marmoset is probably the most commonly kept primate. Its small size and ready availability mean that it has branched out from zoo and laboratory collections into the pet trade.

Consultation and handling

Common marmosets vary in their acceptance of handling, and one should also be mindful of the risk of bites and zoonosis.

Blood sampling

Femoral vein: No more than 1% body weight every 2 to 3 weeks. Apply pressure to prevent a hematoma forming. Smaller volumes can be taken from the saphenous vein.

Nursing care

Thermoregulation

Individual marmosets, with their small body size, can be prone to hypothermia. For general principles, see “Thermoregulation” under Nursing Care in Chapter 2.

Fluid therapy

Either intravenously via the saphenous (will need restraint) or subcutaneously. Volumes up to 3% to 4% body weight can be given subcutaneously in 4 to 5 divided amounts. Select fluids as for other small mammals.

Nutritional support

Marmosets in recovery can be given commercial omnivore supportive foods; it is thought that marmosets require 150 to 160 kcal/kg body mass per day (Morin 1980). The National Research Council (1978) recommends 3.5 to 4.5 g/kg body mass per day of high-quality protein for small primate species. This is particularly so for marmosets with marmoset wasting syndrome (see Marmoset Wasting Syndrome). These should be fed a high-protein, gluten-free diet; such marmosets also appear to need extra calcium (possibly to compensate for reduced uptake).

Analgesia

Anesthesia

Several anesthetic protocols have been described. The author finds the following combination useful, given IM combined in the same syringe:

• Ketamine 5.0 mg/kg plus

• Medetomidine 0.01 mg/kg

• Reverse medetomidine with atipamezole (same volume) IM

Fig 5-1. An induction mask is used to administer gaseous anesthetic and for maintenance with a marmoset.

As an alternative for longer procedures:

Parenteral anesthesia

1. AnalgesiaZpremedication: buprenorphine

2. Ketamine 15.0 to 20.0 mg/kg IM

3. Propofol induction 2.0 to 5.0 mg/kg IV

4. Intubate and maintain on isoflurane.

For cesareans

1. Atropine at 0.02-0.05 mg/kg SC

2. Induce with isoflurane with mask (Fig. 5-1) or in induction chamber.

Mean arterial blood pressure = 95 ± 9 mm Hg

• Intraoperative care

• Keep warm (see “Thermoregulation”).

• Fluids (see “Fluid Therapy”)

• Postoperative aftercare

• Reverse medetomidine (if used) with atipamezole at same volume as medetomidine IM.

• Analgesia—as for other small mammals (see “Analgesia”)

Fig 5-2. Postoperative aftercare for marmosets should include providing a warm, dark, quiet area, such as blankets to hide in that bear the marmoset’s scent, to minimize stress for these intelligent animals.

• Animal must be offered food as soon as it recovers. Hypoglycemia is common in marmosets postoperatively.

• Keep warm and place in darkened, quiet area.

Cardiopulmonary resuscitation

1. Intubate and ventilate at 20 to 30 breaths/min.

2. Reverse medetomidine (if used) with atipamezole at 0.4 to 1.0 mg/kg IM.

3. If cardiac arrest, external cardiac massage at around 100 compressions/min.

4. Epinephrine at

a. 0.2 to 0.4 mg/kg diluted in sterile saline intratracheal

b. 0.2 mg/kg intracardiac, IV, or IO

5. Fluid therapy (see ’’Fluid Therapy”)

6. If bradycardic, atropine at 0.05 mg/kg IV or 0.05 to 0.1 mg/kg intratracheal

Skin disorders

Olfaction is a very important sense for marmosets, and common marmosets possess three areas high in scent glands—the sternal, suprapubic, and circumgenital areas—with the cir- cumgenital fields being especially large and the sternal glands remaining small. The scent marks left are functionally the calling card for each individual, giving information on identity, social rank, and reproductive status (including the ovarian suppression of other females by the dominant female). They are also used for territorial definition and intergroup spacing. Wild common marmosets scent mark 0.19 to 0.45 scent marks/hour (Lazaro-Perea et al 1999), although this is much lower in captive marmosets. Scent marks should be left to accumulate in the enclosure, and when moving the marmoset, it should be accompanied by something bearing its scent.

Pruritus

• Ectoparasites

• Dermatitis

Alopecia

• Tail alopecia (see Marmoset Wasting Syndrome)

• Dermatophytosis

• Poor nutrition

• Trichospirura (see Pancreatic Disorders)

• Zinc deficiency

Scaling and crusting

• Dermatophytosis

• Zinc deficiency

Erosions and ulceration

• Monkeypox (poxvirus—see also “Disorders of the Oral Cavity” in Gastrointestinal Tract Disorders)

• Marmoset poxvirus

• Bite wounds

Nodules and nonhealing wounds

• Calcinosis circumscripta (see Systemic Disorders)

• Blastomycosis (see Respiratory Disorders)

• Anatrichosoma cutaneum (nematode)

Changes in pigmentation

• Measles virus (see Systemic Disorders)

• Vitiligo

Ectoparasites

• Sarcoptes/sarcoptiform mites

• Demodex

• Fleas

Neoplasia

Findings on clinical examination

• Discolored lesions in the skin and nasal cavity (Anatrichosoma cutaneum)

Investigations

1.

2. Bacteriology and mycology: Hair pluck or swab lesions for routine culture and sensitivity.

3. Fine-needle aspirate followed by staining with rapid Romanowsky stains

4. Biopsy obvious lesions.

5. Ultraviolet (Wood's) lamp—positive for Microsporium canis only (not all strains fluoresce)

6. Radiography

7. Routine hematology and biochemistry

8. Culture and sensitivity

9. Endoscopy

10. Biopsy

11. Ultrasonography

TreatmentZspecific therapy

• Monkeypox

• Treat symptomatically.

• Smallpox vaccine will protect against monkeypox.

• Potential zoonosis

• Marmoset poxvirus

• In new imports

• As for monkeypox

• Not known if zoonosis

• Anatrichosoma cutaneum

• Ivermectin 0.2 mg/kg SC or topically; repeat after 4 weeks.

• Bite wounds

• Covering antibiosis

• May require surgery for primary closure to reduce risk of self-mutilation; use subcuticular pattern.

• Dermatophytosis

• Griseofulvin 20 mg/kg PO daily for 30 to 60 days

• Itraconazole 5 to 10 mg/kg PO b.i.d.

• Vitiligo

• Unknown etiology

• Sarcoptes/Demodex

• Ivermectin 0.2 mg/kg SC or topically; repeat after 4 weeks.

• Fleas

• Commercial flea treatments at cat dose rates

• Rare

• Zinc deficiency

• Add zinc to drinking water.

Respiratory tract disorders

Viral

• Paramyxovirus type 1, 2 (simian virus 5 (SV5) and SV41), and 3 (simian agent 10)

• Myxovirus (influenza type A and A2)

• Measles virus (see Systemic Infections)

Bacterial

• Bordetella bronchiseptica

• Klebsiella pneumoniae

• Tuberculosis (Mycobacterium tuberculosis)

• Mycobacterium avium

• Streptococcus (Diplococcus) pneumoniae

• Ureaplasma (see Urinary Disorders)

Fungal

• Blastomyces dermatitidis (blastomycosis)

• Coccidioides immitis (coccidiomycosis)

• Cryptococcus neoformans (see Neurologic Disorders)

Protozoal

• Toxoplasma gondii (see Systemic Disorders)

• Pneumocystis spp.

Parasitic

• Strongyloides stercoralis (pulmonary migration)

Neoplasia

Other noninfectious problems

Findings on clinical examination

• Sneezing

• Coughing

• Dyspnea

• Mucopurulent nasal discharge (bordetellosis, toxoplasmosis)

• Pneumonia

• Pyrexia

• Ocular and nasal discharges

• Anorexia

• Sudden death (bordetellosis, toxoplasmosis)

• Diarrhea (Klebsiella, myxovirus)

• Peritonitis, septicemia (Klebsiella)

• Neurologic signs (S. pneumoniae)

Investigations

1. Tracheal wash/bronchoalveolar lavage

2. Culture and sensitivity

3. Cytology

4. Pleural tap and cytology

5. Radiography

6. Serology for paramyxoviruses

7. Intradermal skin test (tuberculosis)

a. The site for this test is the eyelid, but the small size of the palpebrum means that only a minute volume (0.05 mL) of tuberculin can be injected intradermally. M. avium can cause a false positive so the other eyelid can be used to test for M. avium reaction.

b. The injection site is examined at 24, 48, and 72 hours and is graded.

8. Endoscopy

9. Biopsy

10. Ultrasonography

Management

1. Supportive treatment (e.g., fluids, covering antibiosis)

2. Mucolytics (e.g., 0.5 mg/kg PO bromhexine) may prove beneficial.

3. Reduce stress levels. Hospitalize away from dogs and noisy cats; keep in darkened position.

4. Oxygen therapy if appropriate

TreatmentZspecific therapy

• Paramyxoviruses

• Clinical signs vary from mild upper respiratory tract signs to severe rhinotracheobronchitis and interstitial pneumonia.

• Supportive treatment

• Humans are commonly the source.

• May be more severe in animals younger than age 1 year

• Myxoviruses (influenza)

• Treat symptomatically.

• Mortalities can occur from secondary infections.

• Avoid contact with humans with colds—face masks should be worn to reduce risk of transmission.

• Bordetella bronchisepticum

• Transmitted by aerosol droplets

• Appropriate antibiosis and as described in “Management” above

• Treatment may resolve signs but become subclinical.

• Tuberculosis

• Marmosets with grade 3 result on tuberculin test can be retested every fortnight for 6 weeks until 3 consecutive negative results are obtained. If this fails, euthanize.

• Significant zoonosis. Euthanize.

• Mycobacterium avium

• As for tuberculosis

• Coccidiomycosis, Blastomyces, and mucormycosis

• Miconazole/chlorhexidine (Malaseb, Leo) shampoo—bathe once daily.

• Griseofulvin at 25 mg/kg PO daily for 21 to 30 days

• Itraconazole at 5.0 to 10 mg/kg PO daily for 30 days

• Ketoconazole at 10 to 30 mg/kg PO daily for 60 days

• Pneumocystis spp.

• Potentiated sulfonamides at 30 mg/kg PO b.i.d.

Gastrointestinal tract disorders

Permanent dental formula

Callithriix Jacchus

Dental disease is common in marmosets and is usually associated with inappropriate diet, particularly high levels of fruit with concomitant high levels of sugars (see Nutritional Disor­ders). The high incidence of metabolic bone disease can mean that the periodontal bone is substandard (Johnson-Delaney 2008). Also, although occasionally requested to reduce the risk of injury to the owner, canine removal is not appropriate and represents an unnecessary mutilation. An annual dental checkup is recommended, with preventative work being undertaken.

Disorders of the oral cavity

Dental disease is common and is managed as one would with other small animals.

• Dental disease

• Buildup of tartar and calculus

• Gingivitis

• Dental fractures

• Caries

• Periodontal disease

• Osteomyelitis

• Tooth root abscess

• Typically swelling beneath eye

• Purulent material on aspiration

• Radiography to assess for underlying pathology

• Dental extraction

• Antibiosis—Note: Anaerobes often involved too.

• Hypovitaminosis C—gingival inflammation with hemorrhage and loosening of the teeth (see Nutritional Disorders)

• Papules and ulcers on oral mucosa, accompanied by skin lesions (monkeypox—see Skin Disorders)

• Anatrichosoma cutaneum (see Skin Disorders)

• Gongylonema pulchrum

• Nematode—severe inflammation and edema of the lips; severe pruritis leads to aggravation of the condition. May be in mouth and esophagus.

• Transmitted by cockroaches, so encourage good pest control.

Differential diagnoses for gastrointestinal disorders

Viral

• Measles virus (see Systemic Disorders)

Bacterial

• Escherichia coli

• Campylobacter spp.

• Yersinia enterocolitica

• Shigella sonnei

• Clostridium perfringens

• Helicobacter

• Leptospirosis

Fungal

• Candida

Protozoal

• Cryptosporidium parvum

• Entamoeba histolytica

• Balantidium coli

Parasitic

• Strongyloides stercoralis

• Acanthocephala spp.

• Prostenorchis elegans

• Moniliformis clarki

• Pentastoma spp.

• Pterygodermatites nycticebi (spirurid)

Nutritional

Neoplasia

• GI tract lymphoma

• Small intestine carcinoma

Other noninfectious problems

• Inflammatory bowel disease (IBD—see Marmoset Wasting Syndrome)

• Inflammatory fibroid polyp (Yokouchi et al 2013)

• Gastric bloat

Findings on clinical examination

• Acute hemorrhagic diarrhea (E. coli, worms)

• Chronic, progressive diarrhea (E. coli, worms)

• Watery diarrhea, colitis (Campylobacter, Cryptosporidium)

• Swollen lymph nodes (Yersinia enterocolitica)

• Rectal prolapse

• Dehydration

• Abdominal distension, peritonitis (Prostenorchis elegans)

• Abdominal mass (small intestinal carcinoma, other abdominal lesions)

Investigations

1. Fecal examination

a. Gram stain

b. MZN staining for Cryptosporidium

c. Motile flagellated protozoa (Giardia)

d. Motile ciliated protozoa (Balantidium)

e. Worm eggs

i. Spirurid nematode eggs (Trichospirura leptostoma, but could be Pterygodermatites— see Pancreatic Disorders; capillaria eggs—see Hepatic Disorders)

2. Radiography

a. Foreign body

3. Routine hematology and biochemistry

4. Culture and sensitivity

5. ELISA (Giardia, Cryptosporidium)

6. Endoscopy

7. Biopsy

a. Lymphoma

b. GI tract carcinoma

8. Ultrasonography

Management

1. Fluid therapy (see Nursing Care)

2. If vomiting:

a. Do not feed for 6 to 12 hours and use antiemetics (e.g., metoclopramide at 0.2-0.5 mg/kg SC t.i.d.).

b. Monitor blood glucose—consider dextrose/saline fluids.

TreatmentZspecific therapy

• E. coli

• As in “Management” above

• Antibiotics

• Asymptomatic carriers common

• Potential serious zoonosis

• Campylobacter spp.

• Supportive symptomatic treatment

• May resolve spontaneously

• Zoonotic

• Yersinia enterocolitica

• As in “Management”

• Appropriate antibiosis

• In temperate climates tends to be seasonal, with peaks in late winter and early spring

• Helicobacter

• Appropriate antibiosis

• Gastroprotectants (e.g., sufalcrate)

• Cimetidine 5.0 to 10.0 mg/kg PO

• Leptospirosis

• A cause of severe gastroenteritis

• Appropriate antibiosis

• Potential zoonosis

• Prevent rodent egress.

• Candida

• Occasionally follows prolonged antibiotic treatment

• Nystatin at 100,000 IU/kg PO daily for 10 days

• Giardia

• Common, typically asymptomatic

• Potential zoonosis, so treat with metronidazole 30 to 50 mg/kg daily for 5 to 10 days.

• Tinidazole 2 doses given 4 days apart; first dose at 150 mg/kg PO with second dose at 77 mg/kg (Kramer et al 2009)

• Entamoeba histolytica

• As for Giardia

• Balantidium coli

• As for Giardia

• Cryptosporidium

• More common in marmosets 124.8 nmol/L.

• Treat with oral and injectable calcium supplements such as calcium glubionate at

1.0 mL/kg PO b.i.d.

• Vitamin D₃ at 2000 IU/kg added to the diet

• Salmon calcitonin at 10 IU/kg every 48 hours for 3 weeks. Note: The marmoset must be normocalcemic.

• Reassess environment and diet.

• Supplement during periods of high calcium stress such as pregnancy and lactation. There is some evidence to suggest that reproductively active females increase their calcium intake (Power et al 1999) and that vitamin D₃ marginal individuals show a degree of preference for calcium solutions over plain water.

Obesity

• Very common in captive marmosets

• Linked to poor diet, sedentary existence, and single pet

• Defined (Tardif et al 2009) as:

• Total body fat or relative body fat >14% (58.2 g) in males and >17% (73.4 g) in females

• Average HDL: 0.055 mmol/L

• Reassess diet; reduce carbohydrate intake.

• See also “Hepatic Lipidosis” in Hepatic Disorders and “Diabetes Mellitus” in Pancreatic Disorders.

Hypovitaminosis C

• A lack of vitamin C causes scurvy.

• Seen in marmosets not supplemented properly or fed out-of-date commercial diets

• Signs include swelling of the epiphyses of long bones, gum hemorrhages, loosening teeth, periosteal hemorrhages, and cephalohematoma.

• Radiography is useful in diagnosis.

• Treat with vitamin C supplements up to 25 mg/kg PO body weight b.i.d. PO for 5 days in severe cases.

• Maintenance levels regarded as are 1.0 to 4.0 mg/kg PO body weight daily.

Hypovitaminosis E

• Linked to anemia, myopathies, and pansteatitis (Juan-Salles et al 2003)

• Signs include weight loss, fecal retention, diarrhea, difficulty in moving, anemia, hypoproteinemia, or hypoalbuminemia.

• Biochemistry: raised creatine kinase, lactate dehydrogenase, and alanine transaminase and renal failure with hypercholesterolemia

• Supplement with vitamin E.

Coprophagy

• Usually secondary to inadequate nutrition, especially low-protein diets

• Correct any dietary deficiencies.

• Install a grate into the bottom of the cage to reduce access to feces.

Hepatic disorders

Viral

• Lymphocytic choriomeningitis (LCM, arenavirus)

• Yellow fever (Flavivirus)

• Hepatitis G virus (GB virus C)—see Systemic Disorders)

Bacterial

• Yersinia pseudotuberculosis (see Systemic Disorders)

Parasitic

• Capillaria hepatica

Nutritional

Neoplasia

Noninfectious disorders

• Amyloidosis (see Systemic Disorders)

• Cholelithiasis (Smith et al 2006)

• Fatty liver disease/steatohepatitis (Kramer et al 2015)/hepatic lipidosis

Findings on clinical examination

• Reduced appetite or loss of appetite

• Vague signs of ill health

• Abnormal feces, diarrhea

• Emesis

• Hepatomegaly

• Weight loss, lethargy, hepatomegaly (amyloidosis)

• Jaundice

• Ascites

• Dyspnea

• Bile-tinged (green) diarrhea

• Abnormal gait

• Seizures

• Hemorrhages

Investigations

1. Fecal examination

a. Capillaria hepatica eggs (typical bipolar)

2. Radiography

3. Routine hematology and biochemistry

a. Raised liver enzymes

b. Leukocytosis

c. Anemia

4. Culture and sensitivity

5. Virus isolation (yellow fever)

6. Endoscopy

7. Biopsy

8. Ultrasonography

Management

1. Fluid therapy (see Nursing Care)

2. Lactulose at 0.25-1.1 ml/kg PO b.i.d or t.i.d.

3. Milk thistle (Silybum marianum) is hepatoprotectant. Dose at 4 to 15 mg/kg PO b.i.d. or t.i.d.

TreatmentZspecific therapy

• LCM

• Transmitted by ingestion of rodents, either wild rodents or pinkies given as part of diet

• Attempt treatment with general supportive care (see “Management” above).

• Zoonosis, so consider euthanasia.

• Prevent access to rodents, and assess sources of dietary rodents.

• Capillaria hepatica

• Fenbendazole 50 mg/kg PO every 2 weeks until clear

• Avoid rodents (primary host).

• Hemosiderosis

• Unexpected mortalities

• Linked to diet (Miller et al 1997); may be due to excessive scavenging of dietary iron in a species that feeds naturally on an iron-deficient diet; the lack of naturally occurring tannins may also be important.

• May also be related to feeding of homemade diets, possibly with high fruit/vitamin C. Alternatively can be triggered by chronic inflammatory disease. Hypervitamosis C and chronic inflammation can increase transferrin levels.

• Minimize fruit in diet (see Nutritional Disorders); if using human milk substitutes for hand-rearing, choose a low-iron formula.

• Yellow fever

• Marmosets are relatively resistant but may still show signs.

• Outbreaks typically follow importation/arrival; if die-offs occur within 10 days with appropriate signs, then consider yellow fever.

• Protect from mosquito vectors.

• Potential zoonosis; vaccinate staff.

• Cholelithiasis

• Surgical removal

• Covering antibiosis and as for Management

• Dietary reappraisal; in Smith et al (2006) the stones were found to be largely pigment stones, although two were cysteine.

• Fatty liver disease/steatohepatitis/hepatic lipidosis

• Can be linked to obesity combined with anorexia

• Aggressive fluid therapy

• Parenteral nutrition with glucose and vitamins

• Calcium gluconate PO or propylene glycol PO may be of use.

• Dexamethasone at 0.2 mg/kg IV, SC, or PO. Can be repeated after 24 hours if necessary.

• See also “Obesity” in Nutritional Disorders.

Splenic disorders

• Splenomegaly

• Hemangiosarcoma and hemangioma

• Cardiac disease (see Cardiovascular and Hematologic Disorders)

• Lymphoma/lymphosarcoma (see Systemic Disorders)

• Idiopathic splenomegaly

Treatment

• Address underlying cause.

• Splenectomy

• Hypersplenism

• Splenic rupture

• Splenic torsion

• Neoplasia

• Splenitis

Pancreatic disorders

Parasitic

• Trichospirura leptostoma (spururid nematode)

Neoplasia

Other noninfectious problems

• Diabetes mellitus type II (Juan-Salles et al 2002)

• Insulin resistance (Juan-Salles et al 2002)

Findings on clinical examination

• Ataxia and hind-limb paresis

• Lethargy

• Hypersalivation

• Vomiting

• Abdominal distension

• Pain

• Weight loss and emaciation despite normal appetite, alopecia, muscle weakness, ataxia, hind-limb paralysis (T. leptostoma)

• Poor weight gain in juveniles and increased mortality of newborns (T. leptostoma)

• Obesity

Investigations

1. Radiography

2. Fecal examination: spirurid nematode eggs (T. Ieptostoma)

3. Routine hematology and biochemistry

a. T. Ieptostoma can trigger a subclinical pancreatitis with secondary pancreatic insufficiency.

b. Hyperglycemia/glycosuria (diabetes mellitus/insulin resistance)

4. Glucose tolerance curve (from Fox 2002)

5. Culture and sensitivity

6. Urinalysis

a. Glycosuria/ketonuria

7. Endoscopy

8. Exploratory surgery and biopsy

9. Ultrasonography

Management

1. Treatment of hypoglycemia (see box)

Hypoglycemia

1. Rub honey or sugared water onto the gingiva, taking care not to get bitten.

2. 0.5- to 2.0-mL total volume bolus IV of 50% dextrose solution given slowly

3. Fluid therapy (see Nursing Care) with 5% dextrose infusion

4. If marmoset fails to respond, can give shock dose of dexamethasone at 4 to 8 mg/kg IV or IM onceonly.

5. Diazepam at 1 to 2 mg IV as needed to control if seizures persistent

TreatmentZspecific therapy

• Diabetes mellitus

• May be controlled by limiting carbohydrate in diet. Feeding snacks high in unsaturated fats and protein (cashew nuts and waxworms) appeared to improve glucoregulation (Ziegler et al 2013b).

• Oral antidiabetic drugs: metformin at 5.0 to 10.0 mg/kg PO b.i.d.

• If necessary start on neutral protamine Hagedorn (NPH) insulin at a starting dose of 0.1 IU/marmoset SC b.i.d. until stablized. Monitor blood glucose levels.

• Maintain on daily ultralente insulin.

• Linked to obesity, sedentary lifestyle, lack of socialization, and early weaning. Obese marmosets can develop type II diabetes mellitus from age 5 years on.

• T. Ieptostoma

• Fenbendazole 50 mg/kg PO s.i.d. for 14 days.

• Cockroaches Blatella germanica and Supella Iongipalpa are intermediate hosts, so they need to be eliminated.

Cardiovascular and hematologic disorders

Bacterial

• Bacteremia/septicemia

• Endocarditis (especially staphylococci—Chamanza et al 2006)

• Pericarditis

Protozoal

• Toxoplasma gondii (myocarditis—see Systemic Disorders)

• Trypanosoma cruzi

• Dipetalonema

Nutritional

• Atherosclerosis

Neoplasia

• Lymphoma (see Systemic Disorders)

• Myelofibrosis

Other noninfectious problems

• Myocardial fibrosis

• Cardiomyopathy

• Dilative

• Chronic/focal myocarditis

• Femoral artery hematoma

• Perivasculitis/vasculitis

• Mineralization

• Ectopic thyroid

• Valvular heart disease

• Congenital disorders

• Anticoagulant drug poisoning (rodenticides)

Findings on clinical examination

• Cyanosis or pallor of the mucous membranes

• Slow capillary refill time

• Dyspnea

• Precordial thrill

• Abnormalities of femoral arterial pulse, including weakness, irregularities, pulse deficits

• Arrhythmia

• Lack of thoracic percussion with auscultation

• Abnormal lung sounds

• Abnormal heart sounds

• Exercise intolerance

• Ascites

• Hepatomegaly, splenomegaly (Trypanosoma cruzii)

• Weight loss

• Sudden death

• Swelling of medial aspect of quadriceps muscle; obvious hematoma following phlebotomy (femoral artery hematoma)

Investigations

1. Auscultation

2. Blood pressure

3. ECG

4. Routine hematology and biochemistry

a. Pancytopenia, leukoerythroblastosis, anisocytosis, poikilocytosis, giant platelets (myelofibrosis)

b. Smear (T. cruzii, Dipetalonema)

5. Serology for Toxoplasma, T. cruzi

6. PCR T. cruzi

7. Culture and sensitivity

8. Endoscopy

9. Biopsy

a. Marrow: fibrosis, atypical megakaryocytes (myelofibrosis)

Management

• Reduce stress (e.g., keep in a cool, shaded, or darkened area away from potential stressors such as dogs).

• Provide a high-oxygen environment.

• For pleural effusion, consider tube thoracostomy.

TreatmentZspecific therapy

Specific treatments for cardiac disease not described, so consult human literature as well as established veterinary protocols.

• Cardiomyopathy

• Dilated (congestive) cardiomyopathy

- Furosemide at 1 to 4 mg/kg PO, SC b.i.d.

- Enalapril at 0.5 mg/kg PO every 48 hours

- Benazepril 0.25 to 0.5 mg/kg PO daily; less nephrotoxic than enalapril

- Digoxin at 0.01 mg/kg PO daily

- Nitroglycerin at 3 mm of 2% ointment applied to skin daily or b.i.d.

- Pimobendan at 0.2 mg/kg PO daily

• Valvular heart disease

• Treat as for dilated cardiomyopathy

• Myelofibrosis

• Very guarded prognosis

• If diagnosed antemortem, consider blood transfusions, erythropoetic growth factors, and prednisolone (1 mg/kg PO daily). Consult present recommendations for human medicine.

• T. cruzi

• Transmitted by trauma, direct exchange of bodily fluids, and transplacental

• Can be transmitted by insects, so good insect control needed

• Benzimidazole 5.0 to 7.5 mg/kg PO b.i.d. for 60 days

• Nifurtimox 15 to 20 mg/kg PO t.i.d. for 90 days

• Potential zoonosis

• Dipetalonema spp.

• Microfilariae found in peripheral blood smears

• Adults found in pleural cavity and peritoneum.

• Ivermectin at 0.2 mg/kg SC or PO; repeat after 4 weeks.

• Transmitted by blood-sucking fleas and ticks, so ectoparasite control is essential.

• Femoral artery hematoma

• If noticed immediately, then apply a pressure bandage.

• If long-standing, may require surgical resection; may need blood transfusion prior to surgery.

• Anticoagulant drug poisoning

• Treat with vitamin K IV and PO.

• Consider transfusion if necessary.

• General supportive care.

Systemic disorders

Viral

• Herpes simplex virus 1 (HSV-1)

• Herpesvirus tamarinus

• Herpesvirus saimiri (HVS)

• Herpesvirus ateles

• Epstein-Barr virus (EBV)

• Callitrichine herpesvirus 3 (CalHV-3)

• GB virus A (flavivirus)

• LCM (see Hepatic Disorders)

• Measles virus (morbillivirus)

• Eastern equine encephalitis virus (EEEV)

Bacterial

• Franciscella tularensis

• Streptococcus Zooepidemicus

• Yersinia pseudotuberculosis

• Clostridium botulinum (botulism)

Protozoal

• Toxoplasma gondii

Parasitic

• Trichospirura leptostoma (see Pancreatic Disorders)

• Dipetalonema spp. (see Cardiovascular and Hematologic Disorders)

Nutritional

• Hypovitaminosis E (see Nutritional Disorders)

Neoplasia

• Lymphoma

• Malignant T-cell lymphoma (Yamaguchi et al 2013)

Other noninfectious problems

• Amyloidosis

• Calcinosis circumscripta (Wachtman et al 2006)

Findings on clinical examination

• Fever, lethargy, and anorexia followed by conjunctivitis and salivation due to oral vesicles; commonly progresses to ataxia, paresis, blindness, seizures, and death (HSV-1, herpesvirus tamarinus)

• Lethargy, anorexia, abdominomegaly, lymphadenopathy, exophthalmos (malignant lymphoma, HVS, herpesvirus ateles, EBV)

• Anorexia, weight loss, diarrhea, and abdominal masses (CalHV-3)

• Swollen lymph nodes, lethargy, anorexia (Franciscella tularensis)

• Wasting and muscle atrophy (Trichospirura leptostoma)

• Weight loss, lethargy, hepatomegaly (amyloidosis)

• Polylymphadenopathy (lymphoma, Streptococcus)

• Firm subcutaneous mass (calcinosis circumscripta)

• Splenitis, enteritis (Streptococcus)

• Diarrhea, lethargy, depression, abortions, stillbirths, and septicemia

Investigations

1. Radiography

a. Radiodense mass; bone density (calcinosis circumscripta)

2. Routine hematology and biochemistry

3. Normochromic, normocytic anemia, hypoalbuminemia, raised alkaline phosphatase

4. Abdominal centesis and cytology

5. Serology for toxoplasmosis, herpesviruses, EBV

6. Culture and sensitivity

7. Virus isolation from infected tissue

8. Endoscopy

9. Biopsy/necropsy

a. Liver biopsy (amyloidosis—beware hemorrhage)

10. Ultrasonography

a. Hypoechoic areas (amyloidosis)

b. Splenic enlargement; organ enlargement (lymphoma)

Management

• See Nursing Care.

TreatmentZspecific therapy

• HSV-1, herpesvirus tamarinus

• Very guarded prognosis: 76% to 100% mortaility with herpesvirus tamarinus

• Attempt treatment with acyclovir, famciclovir, or lysine.

• Marmosets should be kept separate from squirrel monkeys and Cebus monkeys (natural hosts) to prevent transmission of herpesvirus tamarinus to marmosets.

• Avoid contact with humans with active herpes lesions (cold sores).

• Herpesvirus ateles, HVS, EBV, CalHV-3

• Malignant lymphoma

• 40% to 60% captive common marmosets seropositive for CalHV-3 but clinically asymptomatic.

• Viral etiology is likely to make chemotherapy ineffective.

• Consider euthanasia.

• GB virus A

• Typically asymptomatic but can cause acute liver failure

• May reduce immunity of host

• Measles virus

• Hemorrhagic diarrhea with consequential hypothermia, dehydration, and death

• Edema of periorbital area

• Skin erythema and respiratory signs may be absent in marmosets.

• Highly likely to be fatal

• Human attenuated vaccines are suitable.

• Eastern equine encephalitis virus

• Experimentally infected marmosets may be asymptomatic or develop a progressive anorexia, eventually becoming inactive, somnolent, either not blinking or repeatedly blinking their eyes, and exhibiting a depressed posture (Adams et al 2008).

• Avoid exposure to mosquitoes.

• Consider euthanasia.

• Streptococcus Zooepidemicus

• Linked to exposure to raw meat

• Appropriate antibiosis

• Franciscella tularensis

• Appropriate antibiosis

• Yersinia pseudotuberculosis

• Appropriate antibiosis

• Vaccination (autogenous)

• Control rodent and bird vectors.

• Botulism

• Paralysis of laryngeal and respiratory muscles

• Toxoplasmosis

• Primary host is cat, so prevent access to cat feces.

• Can be transmitted by rodents (ingestion of wild rodents) or on insects (e.g., cockroaches), so control of these essential

• Clindamycin at 12.5 mg/kg PO b.i.d. for at least 2 weeks

• Combination therapy consisting of:

- Co-trimoxazole at 30 mg/kg PO b.i.d.

- Pyrimethamine at 0.5 mg/kg PO b.i.d.

- Folic acid at 3.0 to 5.0 mg/kg PO daily

or

- Co-trimoxazole at 30 mg/kg PO daily

- Toltrazuril at 7.0 mg/kg PO daily for 2 consecutive days

- Treat for 3 weeks.

• Amyloidosis

• Often follows chronic inflammatory conditions

• Control by attending to underlying problem.

• Lymphoma

• Very guarded prognosis

• Steroids (e.g., prednisone 1 mg/kg PO s.i.d.) may give temporary improvement.

• Modification of existing chemotherapeutic protocols as described for other animals or humans may be considered.

• Calcinosis circumscripta

• Surgical resection

• Investigate possible underlying etiologies: inflammation/biochemical imbalance.

Marmoset wasting syndrome (MWS)

MWS is an extremely common condition characterized by weight loss, diarrhea, and alopecia, with some cases also developing neurologic signs such as hind-limb paresis. This becomes more common after age 10 years. The several suggested etiologies and the inconsistent clinical signs may indicate a varied spectrum of the same disorder or may be due to misidentification of the condition with something that gives a similar clinical outcome. It may be that the reduction in digestive deficiency seen in MWS also contributes to the development of meta­bolic bone disease by reducing the absorption of dietary vitamin D₃ and calcium (Jarcho et al 2013); see Nutritional Disorders.

Parasitic

• Trichospirura Ieptostoma (see Pancreatic Disorders)

Nutritional

• Hypovitaminosis E (see Nutritional Disorders)

• Gliadin/gluten allergy

• Dietary protein deficiency (see Nutritional Support)

Neoplasia

• GI tract lymphoma

• Small intestinal carcinoma

Other noninfectious problems

• Amyloidosis (see Systemic Disorders)

• Renal disease (see Urinary Disorders)

• Tubulointerstitial nephritis (Brack and Rothe 1981)

• Inflammatory bowel disease (IBD)

• Chronic lymphocytic enteritis (LCE; lymphoplasmacytic inflammation)

- Protein deficiency

- Food allergy (e.g., gliadin/gluten)

Findings on clinical examination

• Chronic, progressive weight loss

• Occasional diarrhea

• Reduced activity

• Muscle wastage

• Weakness

• Tail alopecia

• Necrosis of the extremities is not uncommon with MWS.

Investigations

1. Body weight

a. Adult weight mg for a further 8 weeks.

Musculoskeletal disorders

Viral

• Herpes simplex virus 1 (see Systemic Disorders)

• Herpesvirus tamarinus (see Systemic Disorders)

Bacterial

• Clostridium tetani (tetanus) (see Neurologic Disorders)

Protozoal

• Sarcocystis

Neoplasia

• Rhabdomyosarcoma (Tochitani et al 2013)

Other noninfectious problems

• Traumatic fractures

• Any causes of weakness

• See Neurologic Disorders.

• See Cardiac and Hematologic Disorders.

• See Systemic Disorders.

Findings on clinical examination

• Pain

• Lameness

• Swelling

• Hind-leg paresis/paralysis

• Small rounded mass at tip of tail (chordoma)

Investigations

1. Radiography

2. Osteolysis, pathological fractures (multiple myeloma)

3. Traumatic fractures

4. Routine hematology and biochemistry

5. Culture and sensitivity

6. Endoscopy

7. Biopsy

8. Ultrasonography

TreatmentZspecific therapy

• Multiple myeloma

• No treatment recorded

• Traumatic fractures

• Repair using standard small animal techniques.

Neurologic disorders

Viral

• Herpes simplex virus 1 (see Systemic Disorders)

• Herpesvirus tamarinus (see Systemic Disorders)

• EEEV (see Systemic Disorders)

• Rabies

• Common marmosets have their own rabies variant (Favoretto et al 2001).

Bacterial

• Bacterial meningitis or other CNS infection

• Otitis media/interna

• Clostridium tetani (tetanus)

• Listeria monocytogenes (see Reproductive Disorders)

• Streptococcus (Diplococcus) pneumoniae (see Respiratory Disorders)

Fungal

• Cryptococcus neoformans

Protozoal

• Toxoplasma gondii (see Systemic Disorders)

• Encephalitozoon cuniculi

Parasitic

• Balisascaris

Other noninfectious problems

• Trauma

• Hypoglycemia (see Pancreatic Disorders)

Findings on clinical examination

• Apparent weakness

• Neurologic signs, fever (meningitis—Cryptococcus)

• Posterior paralysis/paresis

• Stiff gait, extensor rigidity, opisthotonos (tetanus)

• Anxiety, lethargy, constipation, bladder atony, posterior paresis, aggression (rabies)

• Epileptiform seizures

Investigations

1. Full neurologic examination

2. Radiography

3. Routine hematology and biochemistry

4. Serology for toxoplasmosis

5. Culture and sensitivity

6. Endoscopy

7. Biopsy

8. Ultrasonography

Management

• Important to differentiate from other causes of weakness (insulinoma, lymphoma, etc.)

TreatmentZspecific therapy

• Encephalitozoon cuniculi

• Co-trimoxazole at 30 mg/kg PO b.i.d. for at least 3 weeks

• Albendazole at 10 mg/kg PO for 6 weeks

• Fenbendazole 10 to 20 mg/kg PO s.i.d. for 1 month

• Combination therapy consisting of:

- Co-trimoxazole at 30 mg/kg PO b.i.d.

- Pyrimethamine at 0.5 mg/kg PO b.i.d.

- Folic acid at 3.0 to 5.0 mg/kg PO daily

• Baylisascaris

• Racoon is the natural host.

• Direct life cycle

• Larva migrans can cause neurologic signs.

• Fenbendazole at 50 mg/kg PO daily for 5 days

• Antiinflammatories

• Consider euthanasia.

• Tetanus

• Treat symptomatically.

• Tetanus antitoxin may help.

• Reduce risk of accidental soil contamination.

• Cryptococcus

• Amphotericin B, at 150 μg∕kg i.v. 3 times weekly for 2-4 months

• Rabies

• Risk of exposure from bites by infected bats, dogs, or other reservoir species in endemic areas or while they are held before export

• Killed vaccines have unknown efficacy but can be used.

• Control risk of infection by barrier methods of protection, safe handling procedures, and prompt and appropriate follow-ups.

• Important zoonosis. Euthanize suspected individuals.

Ophthalmic disorders

Viral

• HVS

• Measles virus (see Systemic Disorders)

Bacterial

Fungal

• Cryptococcus (see Neurologic Disorders)

Protozoal

• Toxoplasmosis (see Systemic Disorders)

Other noninfectious problems

• Hereditary cataracts

• Idiopathic cataracts

• Retinal degeneration (may be hereditary)

• Periorbital edema (measles virus)

• Trauma

Findings on clinical examination

• Corneal ulceration

• Conjunctivitis

• Nasal discharge

• Uveitis

• Corneal edema, hypopyon, and synechiae

• Cataracts

• Exophthalmos (retrobulbar lymphoma—HVS)

• Megaglobus∕glaucoma

• Night blindness (hypovitaminosis A, retinal degeneration)

• Cataracts (hereditary, idiopathic)

Investigations

1. Ophthalmic examination

a. Schirmer tear test: Mean = -0.46 ± 3.41 mm/min (Callithrix penicillata—Lange et al 2012)

2. Topical fluorescein to assess extent of ulceration

3. Tonometry

a. Intraocular pressure 14.5 ± 3.27 mm Hg

4. Skull radiography

5. Routine hematology and biochemistry

6. Serology for toxoplasmosis

7. Culture and sensitivity

8. Biopsy

9. Ultrasonography

TreatmentZspecific therapy

• Corneal ulceration

• Topical and systemic antibiosis

• Once infection is cleared, treat as for other small animals (e.g., scarification to encourage healing, conjunctival grafts, etc.).

• Uveitis

• Topical ophthalmic steroid or NSAID preparations

• Topical ophthalmic antibiotic preparations plus systemic antibiosis if appropriate

• Enucleation if severe

• Cataracts

• Treat for any uveitis as above.

• Cataract removal either surgically or by phacoemulsification

• Neoplasia

• Enucleation

• Toxoplasmosis—see Neurologic Disorders

Endocrine disorders

All primates are highly susceptible to stress; in the common marmoset the most reliable indicators of stress are fecal cortisol and lymphocyte count (Kuehnel et al 2012).

Table 5-7 Cotton or cotton-eared marmoset: lymphocyte count and fecal cortisol levels.

Kuehnel et al, 2012

Hyperthyroidism or hypothyroidism has not been described clinically. Normal values (Mano et al 1985) are as follows:

• Thyroxine (total T₄): 140.1 nmol/L

• Thyroid-stimulating hormone: 38.1 mIU/L

Urinary disorders

Bacterial

• Cystitis

• Pyelonephritis

• Ureaplasmas (Furr et al 1979)

Nutritional

• Oxalate nephropathy (Vanselow et al 2011)

Neoplasia

• Lymphoma (see Systemic Disorders)

• Malignant nephroblastoma (Zoller et al 2008)

Other noninfectious problems

• Tubulointerstitial nephritis (see Marmoset Wasting Syndrome)

• Chronic interstitial nephritis (often part of MWS—see Marmoset Wasting Syndrome)

• Glomerulonephropathy (Yamada et al 2013)

Findings on clinical examination

• Depression

• Anorexia

• Weight loss

• Polydipsia/polyuria

• Oral ulceration

• Hematuria (urolithiasis, cystitis, neoplasia)

• Hind-leg weakness

• Melena

• Dysuria/polyuria

• Urine dribbling, wet perineum, constant licking at genitalia (urolithiasis)

• Death

Investigations

1. Urinalysis (normal urine parameters extracted from Yamada et al 2013)

Table 5-8 Common or cotton-eared marmoset: Normal urine parameters

Yamada et al, 2013

Management

• Fluid therapy (see Nursing Care)

• Appropriate antibiosis

• For protein-losing nephropathies, consider telmisartan at 1.0 mg/kg body weight PO.

TreatmentZspecific therapy

• Ureaplasmas

• Unknown significance

• Standard anti-Mycoplasma antibiotics should be effective.

• Flurofamide, a potent bacterial urease inhibitor, also eliminated ureaplasmas from marmosets. Dose used: 25 mg/animal PO every 12 hours for 3 doses

• Cystitis

• As for other small animals

• Appropriate antibiosis and analgesia

• Pyelonephritis

• Fluid therapy

• Appropriate antibiosis

Reproductive disorders

Reproduction in common marmosets can be controlled by surgical means such as castration, vasectomy, fallopian tube ligation, or ovarohysterectomy or chemically. Castration or ovario­hysterectomy does not reduce aggression in marmosets.

Chemical methods of reproductive control

• Deslorelin implant (Suprelorin) available as a 4.7-mg or 9.4-mg implant, which should give at least 6 months' and 12 months' contraception, respectively: A GnRH analog, it can cause initial stimulation of the HPG axis before downregulation occurs, so sexes are best not mixed for 3 weeks, or an alternative control must be used. This is probably the safest.

• Progesterone-containing implants: Act by altering uterine environment to prevent embryo implantation

• MGA (melengestrol acetate) implant (only available in the United States)

• Etonogestrel 68 mg implant.

• Porcine zona pellucida (PZP) vaccine: Not effective until at least 2 injections have been given, 2 to 4 weeks apart; then another 2 weeks before mixing sexes

Bacterial

• Listeria monocytogenes

• Prostatitis

• Metritis/pyometra

• Mastitis

Neoplasia

• Prostatic hyperplasia

• Mammary carcinoma

• Uterine carcinoma

• Testicular neoplasia

Other noninfectious problems

• Endometrial hyperplasia

• Endometritis

• Pyometra

• Abortion

• Stress

• Toxoplasmosis (see Systemic Disorders)

• Listeriosis

• Leptospirosis (see Gastrointestinal Tract Disorders)

• Placenta previa

• Dystocia

• Physical abnormalities

• Large young (single baby)

• Deformed/anasarca young

• Maternal pelvic abnormalities (e.g., history of metabolic bone disease)

• Placenta previa

Findings on clinical examination

• Abortion, sick neonates; meningoencephalitis in young (see also Neurologic Disorders and Neonatal Disorders)

• Obvious dystocia (Fig. 5-3)

Fig 5-3. An obvious case of dystocia in a common marmoset. This singleton was too big for this primiparous female to give birth to.

Investigations

1. Radiography

a. Dystocia

2. Routine hematology and biochemistry

a. Calcium levels—metabolic bone disease

3. Urinalysis

4. Culture and sensitivity

5. Endoscopy

6. Biopsy

7. Ultrasonography

a. Prostatic hyperplasia/cysts

b. Metritis/pyometra

c. Dystocia

Management

1. Supportive care as outlined in Nursing Care

2. Prophylactic antibiotics

TreatmentZspecific therapy

• Prostatic hyperplasia

• Common in aging males. Usually asymptomatic.

• Testicular neoplasia

• Castration

• Endometrial hyperplasia, endometritis, and pyometra may be linked to hormonal implants.

• Endometritis

• Induce uterine contractions with 0.5 mg prostaglandin F_2α SC.

• Antibiosis

• Pyometra

• Ovariohysterectomy

• Antibiosis

• Neoplasia

• Mammary carcinoma: Mastectomy

• Uterine carcinoma: Ovariohysterectomy

• Mastitis

• Antibiosis and fluids

• NSAIDs may have antiendotoxin effects (see “Analgesia” in Nursing Care).

• Debride or surgically resect affected mammary tissue.

• Fostering young may spread pathogens to other females.

• Abortion

• Investigate causes.

• Supportive care of the dam

• Placenta previa

• Placenta covers entrance to cervix.

• Will initiate a cesarean

• Dystocia

• Birth is usually quick and occurs at night. Typically twins; occasionally triplets and quadruplets are produced.

• If young obviously still in pelvic canal are discovered in the morning, the babies are likely to be dead.

• Stabilize with fluids, calcium, and covering antibiosis.

• Consider immediate cesarean if young likely to be alive. However, if considered dead (ultrasonography, excessive time before presentation) and radiography reveals no obstruction or pelvic abnormality (e.g., from historical metabolic bone disease), then can try oxytocin at 1.0 to 2.0 IU IM, repeated every 20 minutes for 4 injections.

• Place somewhere warm, dark, and quiet.

• If this fails or there are other complications, consider cesarean.

• Use subcuticular sutures; an abdominal bandage may need to be applied to prevent interference with the sutures postoperatively.

• Provide analgesics.

• The female may need to be kept separate from her normal group during recovery, as other group members may interfere with the sutures while grooming. However, one should not allow social bonds to break down, so housing her in sight, scent, and ear shot of the rest will help, although make sure they cannot access her through cage mesh.

Neonatal disorders

Marmosets typically produce twins, but occasionally triplets may be born. The weakest one will usually die within 1 week of birth unless either hand-reared or given supplemental feeds. In such situations human milk substitutes are generally adequate but require the addition of extra protein, carbohydrate, and total lipids, plus a small amount of fish oil to improve the fatty acid composition.

Bacterial

• Listeria monocytogenes

Other noninfectious problems

• Hypothermia (especially in first few weeks as young are unable to thermoregulate). If hand-rearing, maintain temperatures at 35° to 42° C.

• Lack of maternal milk

• Mastitis (see Reproductive Disorders)

• Maternal metritis (see Reproductive Disorders)

• Maternal systemic illness

Findings on clinical examination

• Lethargy

• Failure to feed

• History of lack of maternal care

• Failure to grow

• Diarrhea (may not be apparent as female continually licks clean)

• Neurologic signs in neonates (listeriosis)

Investigations

1. Weigh young daily

2. Radiography

3. Routine hematology and biochemistry

4. Culture and sensitivity

5. Endoscopy

6. Biopsy

7. Ultrasonography

Management

• Nursing care, especially provision of warmth and fluids, is extremely important with neonates.

TreatmentZspecific therapy

• Lack of maternal milk production

• Supplement with commercial milk substitute, altered as outlined above.

• Foster only if appropriate to do so (may transfer pathogens between females).

• Investigate underlying problem in the dam.

• Listeria monocytogenes

• Appropriate antibiosis and supportive treatment

• Prevent contamination of feed.