Journal of the American Association for Laboratory Animal Science
Volume 47, Number 3, May 2008

ORIGINAL RESEARCH
Biology
Abatan et al.  Evaluation of Saphenous Venipuncture and Modified Tail-clip Blood Collection in Mice, pp. 8-15

Domain 1. Task 1 TT1.1.b
Primary Species: mouse

SUMMARY: This study compared two commonly used methods of blood collection in mice using behavioral observations, plasma corticosterone levels, body weights and CBC’s.  0.4μl of blood was collected from female ICR mice using either saphenous venipuncture (using a restraint tube) or a modified tail clip (using minimal restraint).  Novices vs. experienced handlers were compared as well.  Saphenous venipuncture yielded higher mean corticosterone levels however the results did not achieve statistically significant differences between the two methods.  The number of mice that pulled away from the handler was significantly higher for the saphenous venipuncture than for the modified tail clip method.  CBC results revealed that WBC, neutrophil, and lymphocyte counts were significantly higher for the modified tail clip method than for the saphenous method.  When the technical expertise of the handlers was compared the experienced handler took less time to perform the procedures, and fewer distress behaviors were exhibited by the mice and lower corticosterone levels (saphenous technique but not the tail clip method).  Serially collected corticosterone levels did not significantly differ between the two blood collection methods.  When the effect of serial blood collection on behaviors were compared, mice displayed more pulling on day one and more flinching behavior on day 6 and 8 with the saphenous method.  Although this study did not find one method to be superior, it highlights the importance of consistency of blood collection methods when measuring corticosterone levels or WBC counts in mice.

QUESTIONS:
1.	True or false.   WBC counts tend to be higher in more peripheral sites?
2.	When should corticosterone levels be measured?             

ANSWERS:
1.	True
2.	a

Valentim et al.  The Effects of Depth of Isoflurane Anesthesia on the Performance of Mice in a Simple Spatial Learning Task, pp. 16-19

Task 4- Provide Research Support, Information, and Services; K1 Biomethodology; K5 Anesthesia, analgesia, and patient monitoring
Species:  Primary- Mouse

SUMMARY:  To test the hypothesis that isoflurane anesthesia can alter behavior and cognitive functions the ability of mice to navigate a T-maze was assessed following isoflurane anesthesia.  Male C57BL/6J were habituated to a T-maze one day prior to anesthesia.  They were then exposed to isoflurane at concentrations of 0%, 1%, or 2% in 100% oxygen for 1 hour.  The ability of the mice to navigate the T-maze was then assessed 28 hours after anesthesia.  Animals exposed to 1% isoflurane had statistically significantly poorer T-maze performance than did animals exposed to either 0% or 2% anesthesia.  This was contrary to the expected results which would have expected to see a dose dependent effect wherein higher concentrations of isoflurane would have an equal or greater effect than lower concentrations.  The reason for learning impairment at lower isoflurane concentrations is unclear.  However, the results indicate deeper anesthesia would be preferred for mice used in cognitive or learning research.

QUESTIONS:
1.	What effect did isoflurane anesthesia in mice have on their ability to perform simple learning tasks? 
2.	True or False:  Isoflurane effects on learning occurred in a dose dependent manner.  

ANSWERS:
1.	Isoflurane significant inhibited the learning capability of mice 28 h after anesthesia
2.	False:  Mice exposed to lighter anesthesia (1% isoflurane) had significantly decreased performance as compared to mice exposed to deeper anesthesia (2% isoflurane).

Mook and Benjamin.  Use of Selamectin and Moxidectin in the Treatment of Mouse Fur Mites, pp. 20-24

Primary Species: Mice

SUMMARY: Fur mites are a common pathogen of lab mice. In one study more than 33% of research institutions were reported to have had fur mites in at least 1 of their colonies. Mycoptes musculinus is the most common fur mites of mice which is a surface-dwelling mite feeding on epidermal tissue. Its lifecycle ranges from 8 to 14 d, with eggs hatching in 5 d, and neonates becoming infested within 4 to 5 d of birth.

Transmission is by close contact, and transmission via eggs or nymphs in bedding is the foundation of many sentinel programs. Until recently, ivermectin was the drug of choice for treating fur mites in mice. However, this drug is labor-intensive to use because several treatments are required. Furthermore, ivermectin can cause neurotoxicity and confound behavioral research in some strains of mice, so it must be used with caution. Moxidectin is a milbemycin drug class, similar to avermectins. Selamectin is an avermectin like ivermectin, but has been modified to improve safety. In this article authors treated a breeding colony (250 different strains of mice) with topical selamectin and moxidectin for Mycoptes musculinus.  Selamectin showed no apparent ill effect suggesting that this drug is safe in mice. Comparison between treating of infested mice with selamectin or moxidectin showed moxidectin used in combination with cage changing was effective in eradicating mites, with mice negative for traces of mites on cellophane tape exam of the pelage from months 2 through 12 after treatment but egg casing were found in the selamectin treatment group as late as 6 mo after treatment, promoting concern about effectiveness of selamectin.

QUESTIONS:
1.	T or F:  Selamectin and moxidectin are both effective in eradicating of Mycoptes musculinus in mice colonies even after 12 months of treatment.
2.	 ______________ is the most common fur mites of mice.
3.	Mycoptes musculinus lifecycle ranges from __________ to __________.
4.	What are the problems associated with using ivermectin in treating of mice mites?

ANSWERS:
1.	False
2.	Mycoptes musculinus
3.	Its lifecycle ranges from 8 to 14 d
4.	Ivermectin is labor-intensive to use because several treatments are required, in addition, ivermectin can cause neurotoxicity and confound behavioral research in some strains of mice, so it must be used with caution.

Compton.  Prevention of Mouse Norovirus Infection in Neonatal Mice by Fostering, pp. 25-30

TASK 1. Prevent spontaneous or unintended disease or condition 
TASK 2. Control spontaneous or unintended disease or condition
Primary – mouse (mus musculus)

INTRODUCTION: Noroviruses infect humans, cows, pigs, and mice and are classified as emerging human pathogens and are the etiology for greater than 90% of all epidemic viral gastroenteritis outbreaks in the United States.  Within 48 hours exposure, human norovirus causes diarrhea, nausea, vomiting, and abdominal pain that lasts 1-5 days.  Although humans of all ages are susceptible, elderly, renal transplant patients, and receiving immunosuppressive therapies are at increased risk for severe disease.  Transmission occurs through direct contact, ingestion of contaminated food and water, or via fomites.  The high prevalence of noroviruses in human populations is related to the fact that only a few virus particles are required for infection and the stability of these viruses in the environment and their resistance to many commonly used disinfectants.
 
Murine norovirus (MNV) was identified in 2002 and is currently one of the most prevalent viruses in mouse colonies with MNV antibodies in 22% of sera tested and MNV RNA in the feces of 64% of the mouse strains tested.  MNV-1 causes subclinical infection with minimal tissue pathology in immunocompetent mice with infection limited to the intestines, liver, spleen, lymph nodes, and lungs.  However, MNV-1 causes severe disseminated disease in that includes necrosis of the liver, spleen, lung, brain, and intestines in mice with deficient innate immune responses (Stat1-/-, Rag2-/-/ Stat1-/-, Pkr-/-/ Stat1-/- and IFNαβγR-/-).  Intracerebral inoculation of STAT-/- mice with MNV-1 was fatal by 7 days post inoculation.   MNV adversely impacts immunologic studies using immunodeficient mouse models because it targets macrophages and dendritic cells in the spleen and liver and persists in mesenteric lymph nodes.  Therefore, methods to eliminate MNV from mouse facilities need to be developed.  
 
Efforts to let the infection die out would most likely be unsuccessful since the virus causes persistent infections with fecal shedding for more than a month. The virus is stable between a pH of 2 and 10 and remains infectious for at least 7 days at room temperature in fecal material which makes decontamination difficult and the risk of spread by fomites high.  In this paper, fostering neonatal mice from MNV infected dams to uninfected dams was used as a method to eliminate MNV since fostering has successfully eliminated enteric infections such as murine rotavirus, Helicobacter hepaticus, and mouse hepatitis virus from colonies.
 
SUMMARY: Neonatal Swiss Webster mice (Tac:[SW]) and their dams were inoculated orally on postpartum day (ppd) 1or 2 with 10 ul of fecal homogenates containing MNV isolates.  Neonatal mice were resistant to MNV infection after oral inoculation on ppd day 1 to 3, but became susceptible by ppd 5.  MNV infection was not detected on ppd 10 in mice inoculated on ppd 3; therefore, it is likely that indirect infection of neonatal mice by contact with MNV-infected dams does not occur before ppd 11.  Clinical signs did not occur in neonatal mice or their dams after oral inoculation with MNV but MNV RNA was present in the intestines of mice 5 days of age or older.  The mechanism of resistance of 1-3 day old mice to MNV is most likely related to developmental changes occurring in the lymphoid tissue of the intestine related to the lack of a population of susceptible cells (i.e. macrophages, dendritic cells) in the intestine at ppd 1-3.

Infection of neonatal mice in contact with infected dams, and their waste, occurred after ppd 14, with almost all mice positive for MNV RNA in their feces by ppd 17.  Coprophagy appears to be the primary route of MNV transmission to young mice and coincides with the age at which mice begin to practice coprophagy between ppd 16-18.  The presence of anti-MNV maternal antibodies did not prevent MNV transmission from dams to neonatal mice.  Fostering was successful in preventing MNV infection in 33 of 35 litters of neonatal mice.  
 
The fostering protocol used did not include disinfection of neonatal mice prior to transfer; therefore, the neonatal mice may have served as fomites.  MNV present on their skin was the potential source for infection of 2 MNV-naïve foster dams.  To minimize fomites transmission from neonatal mice to foster dams, disinfection of neonatal mice with disinfectants effective against human noroviruses, such as Virkon, should be considered.  Maternal rejection may occur when neonatal pups are disinfected.  
 
CONCLUSIONS:
1	To eliminate MNV, fostering can be performed any time prior to ppd 6
2	To eliminate multiple agents, fostering should be performed within 24 hours of birth, and the use of medicated feeds should be considered if nonviral agents (H. hepaticus) are to be eliminated.

QUESTIONS:
1.	Mouse Norovirus is a member of which viral family?
a. 	Coronaviridae
b.  	Caliciviridae
c.  	Paramyxoviridae
d.  	Parvoviridae
e.  	Arenaviridae
2. 	Which properties listed below is/are true of Mouse Norovirus?
a.	Enveloped, icosahedral, single-stranded RNA +
b. 	Enveloped, Helical, single-stranded RNA +
c. 	Enveloped, icosahedral, double-stranded DNA
d.  	Non-enveloped, icosahedral, single-stranded RNA +
e.  	Non-enveloped, icosahedral, double-stranded DNA
3. 	Which pathogens can be eliminated if mouse pups are fostered within 24 hours of birth?
a.	Fur mites, Mouse Hepatitis Virus, Mouse Norovirus, Mouse Parvovirus
b. 	Fur mites, Mouse Hepatitis Virus, Theiler encephalomyelitis virus, Mouse Parvovirus	
c.  	Mouse Hepatitis Virus, Murine rotavirus, pinworms, Mouse Norovirus
d. 	Mouse Parvovirus, Mouse Hepatitis Virus, Helicobacter hepaticus, Theiler encephalomyelitis virus
e.   	All of the above
4.  	Which of the follow properties is not true concerning Mouse Norovirus?
a. 	Stable in the environment for at least 7 days in fecal material
b. 	Fomite transmission is possible
c.  	Resistant to several disinfectants
d.  	Aerosol transmission is a common route
e.   Transmitted by direct contact
5. 	T or F:  Mouse Norovirus causes disseminated infections in both conventional and immune deficient mice that result in necrosis of the spleen, lung, brain, and intestines.
 
ANSWERS:
1.	b
2. 	a
3. 	a
4. 	d
5. 	False

Manuel et al.  Soiled-bedding Sentinel Detection of Murine Norovirus 4, pp. 31-36

Domain 1: Management of Spontaneous and Experimentally Induced Diseases and Conditions
Primary spp- Mus musculus

SUMMARY: The efficacy of soiled bedding transfer for identifying norovirus was evaluated in this study and included several key points that can help facilities in designing a prudent health surveillance program. ICR mice were used and received a measured amount of dirty bedding over a 12 week period. Virus was found in 80% of the cages and was shed in the feces. MNV RNA in fecal pellets from positive sentinels were found to be stable (tested by RT-PCR) for as long as 2 weeks. Pooled samples were also evaluated and found to be positive for MNV by RT-PCR of either 9 or 19 pellets. Although detection was high, failures can still occur with indirect sentinel testing. Cohoused sentinel testing did show a high level of agreement among positive MNV animals.
 
QUESTIONS:
1. 	What contributes to the success of detecting MNV in a facility by soiled bedding transfer?
2. 	What is different about MNV strains?
 
ANSWERS:
1. 	Prolonged fecal shedding in immunocompetent mice
2. 	MNV2, MNV3, and MNV4 differ from the prototypic MNV1 strain by causing persistent infection

Bryda and Riley.  Multiplex Microsatellite Marker Panels for Genetic Monitoring of Common Rat Strains, pp. 37-41

Domain 3 Research; Knowledge 5

SUMMARY: Authors devised a rapid, cost effective tool to use for genetic monitoring of common rat strains.  Authors developed a genotyping panel of 87 microsatellite markers to assess ACI, Fischer 344, Lewis, Brown Norway, Wistar-Furth, and Wistar Kyoto rats.  Authors assayed the rat genome with only 8 PCR reactions by using fluorescent labeled primers and multiplex PCR analysis.  Size and fluorescent dye were used as distinguishing factors.  Capillary-based electrophoresis was used to determine allele size.  These methods are useful for routine detection of genetic contamination and for genome analysis for production of speed congenics, gene mapping, and background strain characterization.

QUESTIONS: 
1.  	Define SSLP
2.  	Which represent inbred rats strains?
a.  	Lewis, Sprague Dawley, Brown Norway
b.  	Long Evans, Sprague Dawley, Zucker
c.  	Gunn, Brattleboro, Nude
d.  	Lewis, Brown Norway, Fischer 344
e.  	Fischer 344, Nude, Lewis

ANSWERS:
1.  Simple sequence length polymorphisms = microsatellites.  These are DNA regions containing di-, tri-, or tetra-nucleotide repeats that are found randomly yet abundantly throughout the genome.
2.	d

Lemke et al.  Infestation of Wild-caught American Bullfrogs (Rana catesbeiana) by Multiple Species of Metazoan Parasites, pp. 42-46

Species:  Tertiary, bullfrog

SUMMARY: Necropsies of a group of wild-caught bullfrogs were performed as part of an acute experiment.  The frogs were noted to be emaciated at the time of necropsy.  Numerous parasites were observed on necropsy.  Crickets fed to the frogs were tested and found to be negative for parasitic ova and larvae, thus the authors concluded the frogs were infested upon capture.  The purchase of vendor or laboratory bred and raised stock is advised.

Parasites discovered at necropsy:
1	Eustrongyloides spp  Coiled adult nematodes attached to stomach wall and at gastroduodenal junction
2	Contracaecum spp  Nematodes within nodules (granulomas) on gastric serosa and intestinal submucosa
3	Haematolechus breviplexus  tan-yellow, mottled trematodes in lungs
4	Gorgodera amplicava  Light-yellow trematodes attached to urothelium
5	Clinostomum spp Trematode larvae within yellow cysts attached to skeletal muscle
6	Cosmocercoides dukae 2cm long white nematodes in intestines

There were also a few parasites that could not be identified.

QUESTIONS:
1. 	T or F:  Rana catesbeiana is an herbivorous species
2.  	T or F:  Injection of a barbiturate into the dorsal lymph sac is a conditionally acceptable method of euthanasia for amphibians

ANSWERS:
1. 	F
2.  	F  (it is acceptable)

Colony Management
Huerkamp and Dowdy.  Diet Replenishment for Ad-libitum-fed Mice Housed in Social Groups is Compatible with Shelf Life, pp. 47-50

Domain 4: Animal Care; K13. watering and feeding (e.g., automated watering, liquid diets, ad lib or restricted diets)

Species: Primary-mouse

SUMMARY: Regulatory guidelines allow diets milled for laboratory animals to be used within 180 days of formulation, but otherwise permit latitude and professional judgment in how and when feed is offered.  Some research institutions allow for “topping up” of chow over existing chow in food hoppers, while others replace all chow on a regular basis (i.e. at cage change).  This study looked at the length of time it took for a full hopper of chow (250 g) to be consumed by breeding mice or (500 g) gender-specific groups of weanlings housed in ventilated cages.  They filled a 250 g hopper with dyed chow and topped it off with undyed food at day 14, 24, 35 and 44.  At day 24 the hopper was topped up with undyed, higher fat-content chow.  It was found that breeding pairs consumed 97% of the original chow within 44 days of offering, and none of the original chow remained in the hoppers of ten out of 11 cages at day 56.  Less than 2% of the original chow remained in the 11th cage at day 56.  Prior to day 24, the mice consumed food at a rate of 4.7±0.5 g/mouse daily; after day 24 (when the higher fat feed was added) the mice consumed 6.2±0.7 g/mouse daily.  At these rates of consumption, a 250 g hopper of laboratory rodent chow would be exhausted in 20 to 27 days, depending on diet type.  Gender-specific groups of weanling mice were offered 500 g of dyed food originally, and were found to have consumed 95% of the diet within 24 days of offering, and all but 0.2% of the diet remained at day 35.  After day 24, mice consumed the feed at a rate of 3.4±0.3g/mouse daily and at a pace that would empty the 500 g ration for a typical cage of 5 young and growing mice in 30 days.  Singly-housed animals were not evaluated in this study, but it was mentioned that they might take longer to deplete a full hopper of chow, for obvious reasons.  The authors cautioned against topping up of chow in facilities/housing situations where relative humidity is >50% (i.e. summer months in the northern hemisphere, static filter-top cages).  

QUESTIONS
1.	How would a high relative humidity affect the quality of rodent chow?
2.	T/F: It is acceptable to “top up” rodent chow in feed hoppers, as breeder mice will consume most of the original chow in about 1 month.
3.	T/F: Breeder mice consume lower fat-content chow faster than higher fat-content chow.

ANSWERS
1.	If relative humidity is >50% mold may proliferate, spoiling the chow.
2.	This is true for mice housed in ventilated cages; if static filter-top caging is used, the relative humidity must be taken into account (again, to prevent mold contamination of the feed).
3.	False.  Breeder mice consumed higher fat-content chow at a faster rate than lower fat-content chow in this study.

Thom and Crockett.  Managing Environmental Enhancement Plans for Individual Research Projects at a National Primate Research Center, pp. 51-57

Domain 4: Animal Care
Task 2: Manage or provide indirect management/oversight of laboratory animal facilities
 
SUMMARY: This article describes a method for managing environmental enhancement plans for individual research projects at a national primate research center. This group has a Psychological Well-being Program (PWB) that developed an Environmental Enhancement Plan form (EEPL) that allows the group, PWB, quantify and track changes. The EEPL form includes instructions and questions pertaining to each element of the environmental enhancement plan. The plan specifies minimum enrichment standards for all nonhuman primates housed at the NPRC. Any primate not receiving the minimum enrichment must be covered by an approved exemption. The EEPL provides a place for investigators to indicate the types of enrichment appropriate for the study and to provide scientific justification for requested exemptions. This information helps the staff to coordinate the enrichment for each project. The EEPL form is completed by the principal investigator or designee and forwarded to the PWB staff. The EEPL is reviewed by the PWB staff before being forwarded to the IACUC. If the investigator has selected enrichment below the plan minimum the PWB staff makes an initial assessment of the rationale for the exemption. After the EEPL is reviewed by the PWB they submit it to the IACUC prior to IACUC review of the corresponding Project Review Form. Each investigator is required to review their EEPL annually at the time of IACUC protocol review. The EEPL form facilitated educating the investigators about the enrichment their monkeys will receive and greatly enhanced the staff's ability to coordinate the specific enrichment requirements of a project. The review of each plan by the IACUC improved the ability of the PWB program to suggest a higher level of enrichment. 
 
QUESTION:
1. What are some abnormal behaviors that can be observed by captive non human primates? 

ANSWER:
1.	Floating limb, self-biting, self-clasping, self-sucking, stereotypic pacing, body-rocking, excessive grooming

CASE REPORTS
Feinstein et al.  Fatal Acute Intestinal Pseudoobstruction in Mice, pp. 58-63

Task 3- Provide Research Support Information and Services
Primary Species – Mouse

SUMMARY: This article describes fatal acute intestinal pseudo-obstruction (previously called paresis of peristalsis)  in a mouse breeding colony .  Mice affected were predominately females in their 2nd  lactation.  Forty two female mice, from a 1000 mouse breeding colony were assessed.  Over a 3 year period, 148 mice were found dead.  On gross necropsy, the abdomen was markedly distended with segmental dilatation of the small intestines.  On histopathology, the lymph follicles of the small intestine, mesenteric lymph nodes and spleen exhibited excessive lymphocytolysis. Massive exfoliation of acidophilic and pyknotic epithelial cells  and pronounced apoptosis were also seen.  Neutrophil stasis was also present in those mice with erosive intestinal lesions.    The colony was monitored regularly for rodent pathogens.  Calcium deficiency was considered a possible cause, however, plasma calcium level in the mouse measured was normal.  The cause of the disease remains unclear.

QUESTIONS:
1.	Define intestinal pseudo-obstruction.
2.	Clinical signs seen with (IPO) is 
a.	Abdominal distension
b.	Hypothermia
c.	Arrested lactation
d.	All of the above
3.	T/F Maximal dam milk yield in mice is during the 2 week of lactation
4.	T/F Pups from affected mothers  remained healthy
5.	The predominant  histological lesions in the intestinal mucosa was ______________________________..
6.	The key enzyme triggering apoptosis is __________________________

ANSWERS:
1.	Various motility disorders of the gastrointestinal tract and is characterized by signs of intestinal obstruction in the absence of mechanical blockage of the bowel.
2.	d
3.	True
4.	True
5.	Exfoliation of acidophilic and pyknotic epithelial cells.
6.	Activated caspase 3

Kolappaswamy et al.  Methicillin-resistant Staphylococcus non-aureus Infection in an Irradiated Rhesus Macaque (Macaca mulatta), pp. 64-67

Domain 1, Task 3: Diagnose disease or condition as appropriate
Domain 1, Task 4 – Treat disease or condition as appropriate
Primary Species: Macaques (Macaca spp.)

SUMMARY: This article describes the susceptibility of immunosupressed rhesus macaques to infection with methicillin-resistant Staphylococcus non-aureus strains.  

A 3yr-old male rhesus macaque (Macaca mulatta) developed erythema of the face and periocular edema 44 days after receiving full-body gamma irradiation.  On physical examination, the abnormal findings included increased respiratory rate, dry skin, epithelial sloughing, skin thickening, scaling on the cheeks, erythema on the face and periocular edema.  Blood was drawn for blood chemistry, CBC and culture.  Swabs were taken from the facial lesions, a skin biopsy done and treatment initiated for pyoderma or hypersensitivity-allergic reaction.

The skin culture tested positive for methicillin-resistant Staphylococcus non-aureus, while histopathology revealed epidermal hyperplasia and chronic dermal inflammation.  The clinical records, on review, indicated severe immunosuppression 10 days after irradiation, which was corrected by day 35 post irradiation, after blood transfusions and stem cell reconstitution.  However, while undergoing treatment, animal showed no visible signs of improvement and was euthanized.  Euthanasia was decided upon due to possible risk posed to other immunocompromised animals in study and obvious resistance of organism to treatment.  Possible explanation of condition was that the animal developed the infection secondary to radiation-induced immunosuppression. 

Control and treatment of this particular infection should include isolation or quarantine, enhanced Animal Biosafety Level 2 precautions, antibiotic sensitivity tests and possible fluoroquinolone treatment.

QUESTIONS:
1.	What is the normal TPR for a healthy adult rhesus Macaque?
2.	T/F.  In the aforementioned article, Methicillin-resistant Staphylococcus aureus infections have been isolated in only in humans.
3.	T/F Methicillin-resistant Staphylococcus aureus is zoonotic.

ANSWERS:
1.	T: 36 – 40°C (96.8 - 104°F), P: 150 – 330 beats/min, R: 10 – 25 breaths/min
2.	F: it has been isolated in humans and animals.
3.	T

Lee et al.  Idiopathic New Bone Formation in the Femoral Shafts of a Cynomolgus Monkey (Macaca fascicularis), pp. 68-71

Species: Cynomolgus macaque, primary species

Role delineation: Task 1 Prevent, Diagnose, Control, And Treat Disease: K1- Anatomy, K5- Anatomic Pathology, K-8- Clinical Medicine

SUMMARY: Authors report identifying a novel type of new bone formation in the skeleton system of a 6.5-y-old male cynomolgus monkey.  An animal caretaker observed a bone fragment protruding through the skin of the right leg, and radiographs revealed 2 new bone fragments – one 3.5 cm long growing medially from the medial left femur, and one 6.5 cm long growing laterally from the lateral right femur- clearly distinguishable from the original femurs.  The bone fragments seemed to be inserted into the femurs, although no interrupted lines were noted in either femoral shaft. The new bone shaft on the right side grew distally from the proximal origin of the femur, while the bone shaft on the left side left grew proximally from the distal femoral origin.  The new bone formation did not cause locomotor disturbance and abnormal movement was never observed in the monkey prior to discovery of the protruding bone. Both bone fragments were surgically removed and the animal returned to normal behavior/existence.  The bone fragments had medullary cavities and bone cortex, but incomplete periosteal structure no cancellous bone structure, and no callus formation.  The differing direction of growth of the new bone shafts was unusual and may have reflected different femoral ossification centers, but the underlying cause of the phenomenon was undetermined. Idiopathic new bone formation in a long bone without previous fracture or disease has not previously been reported in monkeys, and growth of a long bone that resulted in penetration of the skin had not been known to occur animals or humans.

QUESTIONS:
1. 	T/F: Idiopathic new bone formation in a long bone without previous fracture or disease has not previously been reported to occur in monkeys?
2. 	In a case report in JAALAS detailing idiopathic new bone formation in the femoral shafts of a cynomolgus monkey, which of the following long bone characteristics were exhibited by the two new bone fragments, which was partially exhibited, and which were not exhibited?
a. 	Medullary cavities
b. 	Bone cortex
c. 	Periosteal structure
d. 	Cancellous bone structure
e. 	Callus formation
3. 	In a case report in JAALAS, idiopathic new bone formation in the femoral shafts was observed in which of the following monkeys?
a. 	Macaca mulatta
b. 	Macaca nemestrina
c. 	Macaca fasicularis
d. 	Macaca arctoides
e. 	Saimiri sciureus
 
ANSWERS:
1. 	True
2. 	a. 	Medullary cavities = YES
	b. 	Bone cortex = YES
	c. 	Periosteal structure = PARTIAL
	d. 	Cancellous bone structure = NO
	e. 	Callus formation = NO
3. 	c. 	Macaca fasicularis