1998 Annual Meeting of the Association for Gnotobiotics. Laboratory Animal Science 48 (5): 434.
Highlights were:
A tribute to Russell W. Schaedler, inventor of the Schaedler's flora that normalizes the gut function of gnotobiotic mice.
Dr. James G. Fox was the keynote speaker, who spoke about using gnotobiotic mice to definitively prove the pathogenicity of Helicobacter species that were previously dismissed as normal flora.
A session was devoted to probiotics (a live microbial feed supplement that fives benefit to the host, most often to the digestive system.) Lactobacilli have been anecdotally linked to good health (anyone here drink L acidophilus milk) and have been recently proven to protect mice from Salmonella mortality.
Dr. Pat Allen presented data of the segmented filamentous bacteria (SFB) of the small bowels of mammals and birds. It has not yet been cultured in vitro. It colonizes the brush border of the columnar epthlium of the small bowel, and is tentatively in the genus Arthromitus.
Dr. Orcutt presented data showing that germfree mice could be maintained and bred for motnths in filter-top cages serviced withing a CLass II safety cabinet.
There were also presentations from major vent-rack suppliers on their newest technologies.
No questions

Rodent Quarantine Programs: Purpose, Prinicples, and Practice. Laboratory Animal Science 48 (5): 438.
BLUF (bottom line - up front): Discusses rodent quarantine programs in general -including four principals for designing and implementing effective rodent quarantine programs, to be used in establishing a quarantine program appropriate for an individual institution's needs. They then present these principles in action with regard to practical considerations for carrying out rodent quarantine. They present their own rodent quarantine program, and the rationale behind their decisions, as a model.
Two basic types of rodent quarantine programs: passive (clinical evaluation only - no testing for specific infectious agents), and active (quarantine period includes testing of the animals or sentinels for specific infectious agents). The authors give support for the importance of active programs and includes a table of considerations for active quarantine program design.
Principles of an Effective Rodent Quarantine Program
1) Determination of the number of animals to be sampled. This must be done to determine an acceptable probability that an agent of interest will be detected if it's present. They discuss statistics behind this principle.
2) Determination of an adequate quarantine period. This should theoretically permit sufficient time for exposure, infection and seroconversion of enough animals for the agents of interest to be detected. They include a table and their own experimental data to help guide and support decisions for establishing the length of a quarantine period.
3) Establishment of conditions that facilitate detection of the agents of interest. Discuss housing conditions, quarantine room set up, etc.
4) Consideration of the sensitivity and specificity of the testing procedures.
Quarantine Programs in Practice
1) Conditions used to determine necessity and cost effectiveness of quarantine programs and practices.
a) As part of this discussion, they include survey results from 49 responding institutions with regard to the type of rodent quarantine program and the duration of the program, as well as what types of animals/vendors are tested.
b) They give some support to the usefulness for quarantine and testing of mice from established/reputable vendors, and include a provocative statement that "infestations of vendor colonies also have been detected with surprising fequency during recent months".
2) Discusses husbandry practices and physical set up of rodent quarantine areas.
3) Discusses use of sentinels versus testing animals directly. They include a short review of the use of soiled bedding for sentinel exposure and its relative effectiveness for detecting various rodent infectious agents
4) Discusses the potential problems associated with rodent parasites related to their life cycles and detection - and the potential usefulness of prophylactic treatment in quarantine versus depending on testing.
5) Finally, mentions other means (e.g., cell lines, mouse serum) for infectious agent introduction into a colony.
QUESTIONS
1) Contrast passive versus active quarantine systems
2) List four principles for designing rodent quarantine programs.
3) What techniques are sometimes used in rodent quarantine in addition to testing for agents.
4) Besides via newly acquired rodents, what are some other ways that infectious agents can enter rodent colonies?
5) With regard to question 4), what is the testing technique called that is used to screen those other possible colony-infecting materials?
ANSWERS
1) Passive: clinical evaluation only - no testing for specific infectious agents; Active: quarantine period includes testing of the animals or sentinels for specific infectious agents.
2) a) Determination of the number of animals to be sampled.
b) Determination of an adequate quarantine period.
c) Establishment of conditions that facilitate detection of the agents of interest
d) Consideration of the sensitivity and specificity of the testing procedures.
3) Prophylactic treatment; e.g., for parasite infection.
4) Cell lines, mouse serum.
5) MAP testing (mouse antibody production testing)

Catheter-Tract Infections in Rhesus Macaques (Macaca mulatta) with Indwelling Intravenous Catheters. Laboratory Animal Science 48 (5): 448.
This retrospective study evaluated the health records of 31 rhesus macaques, which had received a total of 53 long-term indwelling intravenous catheters. The incidence and clinical course of catheter-tract infections were determined along with the incidence of methicillin-resistant Staphylococcus spp. in these infections. A catheter was considered infected after a pathogen was isolated in conjunction with clinical signs of infection at the site. In this study, 16 of the 53 catheters (30%) developed catheter-associated infections. Infections were classified by the site/location as: exit site, local tunnel, surgical site, or segmental. Only segmental catheter-tract infections reduced mean catheter lifespan relative to uninfected catheters (147 to 354 days, respectively). About 42% of bacterial isolates were coagulase-negative staphylococci, while about 23% were Staph. aureus. About 75% (15 of 20 tested) of isolates were resistant to methicillin.
Questions:
1. _____________ catheter-tract infections reduced the mean catheter lifespan relative to uninfected catheters.
2. Name two (2) common sites of colonization for coagulase-negative staphylococci.
Answers;
1. Segmental
2. skin, mucous membranes

Helicobacter bilis/Helicobacter rodentium Co-Infection Associated with Diarrhea in a Colony of scid Mice. Laboratory Animal Science 48 (5): 455.
Diarrhea broke out in a breeding colony of scid/Trp 53 knockout mice. The characteristics of the diarrhea ranged from mucoid or watery to severely hemorrhagic with some mortality. An investigation revealed that the mice had been exposed to conventionally raised mice by an investigator. A variety of methods were used to identify the cause of the diarrhea. Fecal flotation to identify endoparasites was negative. Serologic testing of sick individuals and sentinel mice for various murine viruses was negative. Fresh fecal pellets were homogenized adn plated microaerobically adn cecal contents were cultured. DNA from bacteria (from the plates, feces, and cecal contents) was prepared to develop PCR primers. These amplified Helicobacter bilis-specific sequences and Helicobacter rodentium-specific sequences. Both of the Helicobacters were found in the mice.
The mice with diarrhea were treated with antibiotic food wafers (1.5mg ampicillin, 0.69mg metronidazole, and 0.185mg bismuth/mouse/day) for 2 weeks. This regimen had proviously been successful to eliminate Helicobacter hepaticus in a group of mice. However both of the identified Helicobacters were found in the feces after the treatment was discontinued.
On post mortem the affected mice had multifocal to segmental proliferative typhlitis, colitis, adn proctitis.
This is the first report of H. bilis and/or H. rodentium causing acute diarrhea and may indicate that these are important pathogens for scid mice. Additionally H. bilis may have zoonotic importance because it has a broad host range (rats, dogs, gerbils, cats, and humans).
Questions:
1. What are the viruses that are screened for in mice?
2. What are the most reliable methods to identify Helicobacter species?
Answers:
1. Sendai, mouse hepatitis virus, rotavirus, reovirus 3, pneumonia virus mice, mouse encephalitis (GDVII strain), lymphocytic choriomenigitis virus, minute virus fo mice, ectromelia viurs, K virus, polyoma virus, and adenovirus
2. special culture techniques and species-specific PCR

Genetic Deficiency in a₁Proteinase Inhibitor (a₁ PI) Associated with Emphysema. Laboratory Animal Science 48 (5): 460.
Emphysema is characterized by the enlargement of the airspaces and destruction of the interalveolar septa. This destruction may be due to an imbalance between antiproteases (alpha 1 PI) and elastases released by inflammatory cells in the peripheral lung. If an elastolytic enzyme is not inhibited locally, then the enzyme will damage the alveolar tissue and emphysema will result. This deficiency in antiprotease screen may be genetic (alpha 1 PI deficiency)or acquired (inactivation of alpha 1 PI by cigarette smoke).
Previous animal models of emphysema were induced by installing large doses of a protease with elastolytic activity into the lungs. This model provided biochemical, morphologic, and physiologic data but did not provide data on the pathogenesis of emphysema or allow for therapeutic testing.
This report identifies a severe genetic deficiency of sserum alpha 1 PI associated with low serum anti-elastase screen in the pallid (pa) mouse, in which emphysema occurs spontaneously. This defect was discovered in a wild mouse and placed on a C57BL/6J background by repeated crossings. The mutation is inherited in an autosomal recessive manner and the homozygous phenotype has diluted pigmentation, red eyes, a defect of kidney and neutrophil lysozymal enzyme secretion, and platelet granule defects.
The elastase inhibition/capacity (EIC) was compared among pa, C57BL/6J, and BALB/c mice against mouse leukocyte elastase at 4 days and 2 months of age. BALB/c's had the highest EIC values with C57BL/6J ranking lower (-26%) and the pa mice had the lowest values (-71%). TIC (trypsin inhibition/capacity) showed similar values in all strains of mice.
Serum alpha 1 PI concentrations were determined in the same strains of mice and were 2.7 + 0.4 in the pa, 4.4 + 0.3 in the C57BL/6J, and 5.9 + 0.5 in teh BALB/c mice. These values correlated with the EIC values.
Using an immunogold-electron microscope method, a positive reaction for mouse leukocyte elastase was observed on elastin within the alveolar walls from 2 months on. Elastin contents are normal in pa mice until 8 months of age and decrease significantly by 12 and 16 months of age. Disruption of alveolar septa was first seen histologically at 8 months and patchy areas of air space enlargement with destruction of alveolar septa was seen at 12 months of age and onward. Pulmonary macrophages in pa mice 8 months of age and older contained characteristic intracytoplasmatic crystalloid inclusions bound by a single membrane which were collagen-derived. This suggests that lungs changes in pa mice is the result of an elastolytic process that is caused by a severe deficiency fo serum alpha 1 PI.
The severity of lung lesions in the pa mouse is not as severe as the lung changes in man. Also the alpha 1 PI defiency in humans is often associated with neonatal hepatitis, cirrhosis, and hepatocellular carcinoma. At this point, the hepatic functions of the pa mouse is unknown.
Questions:
1. Where is the pa gene located?
2. Why did the TIC values not change among the 3 strains of mice?
Answers:
1. It co-localizes with the protein 4.2 gene and has been sequenced.
2. The mouse has 2 distinct inhibitors of proteinase. One is specific for elastase (alpha 1 PI) and the other is active against trypsin. If the mice are deficient in alpha 1 PI, trypsin inhibition would not be altered.

Immune Response of Chimpanzees Infected with Human Mycoplasmas. Laboratory Animal Science 48 (5): 463.
Mycoplasmas cause naturally acquired acute or chronic arthritis or joint inflammation. The purpose of the study was to identify the antibody-reactive antigens of the pathogenic clinical synovial isolates by inoculating the chimpanzees intra-articularly or intratreacheally with the isolates and to compare them with the less pathogenic type strains, using immunoblot analysis. Adherence of the bacterial isolates to the cell cultures was suggested to be associated with the ability of the isolates to cause diseases. Mycoplama pneumoniae has been the most characterized human pathogenic species. The authors used a modified Edward-Hayflick broth medium which contained a basal broth component supplemented with horse serum, yeast extract and penicillin G to grow M. hominis and M. pneumoniae. Arginine was added to the medium as an energy source for M. hominis (it is a non-fermented Mycoplama.), and glucose was added for the growth of M. pneumoniae (it is a fermented Mycoplama.). Ureaplamsa urelyticum was grown in the U9 broth medium of Shepard.

SDS-PAGE = sodium dodecyl sulfate-polyacrylamide gel electrophoresis
Mycoplama organisms which may cause Arthritis:
rats, rabbits or mice: M. arthritidis or M. pulmonis;
chickens: M. synoviae or M. gallisepticum;
turkeys: M. gallisepticum;
swine: M. hyosynoviae or M. hyorhinis
human: M. hominis
Mycoplama organisms which may cause Joint inflammation:
chickens or turkeys: M. gallisepticum
cattle: M. bovis or M. mycoides subsp. mycoides
piglets: M. hyopneumonia
sheep or goat: M. agalactiae
Some Microbiology Questions:
1. What does RODAC stand for? What are the main ingredients? What are the functions of the ingredients?
2. What tests to distinguish Staphylococcus from Streptococcus? to distinguish Staphylococcus aureus from S. epidermidis
3. Describe alpha, beta and gammma hemolysis on the blood agars.
4. What is an EMB agar? What is the typical appearance of E. coli colonies on the EMB agar?
5. What is XLD? What is it for? What are the characteristics of the bacterial colonies?
6. What is CFU?
7. What is the requirement to incubate Campylobacter sp.?
8. Cultures of Mycoplamas should not be reported as negative until how much time has passed?
Answers:
1. RODAC = Replicating Organisms Direct Agar Contact; the ingredients are Tween 80 (Polysorbate 80) to enhance growth of the microorganisms and Lecithincase to neutralize the effect of disinfectants.
2. Streptococcus is catalase negative. The reagent is 3% H2O2 (hydrogen peroxide). Staphylococcus is catalase positive (formation of bubbles). Staphylococcus aureus is coagulase positive. S. epidermidis is coagulas negative.
3. Beta hemolysis - lysis of RBC, clearing around the colonies alpha hemolysis - green or browning of the RBC around the colonies gamma hemolysis - no change in RBC on the blood agars.
4. EMB = Eosin-Methylene Blue agar; A green metallic sheen or dark, centered colonies are seen for the typical E. coli colonies.
5. XLD = Xylose Lysine Desoxycholate agar for the recovery of Salmonella and particularly Shigella sp. Salmonella sp. colonies are usually red with black centers; Shigella sp produce translucent colonies.
6. CFU = colony forming units
7. 10% CO2; 5% O2; 85% N2; incubated at 42 degrees Celsius
8. 3 weeks

Efficacy of Hydroquione in the Treatment of Cutaneous Hyperpigmentation in Hairless Descendants of Mexican Hairless Dogs (Xoloitzcuintli). Laboratory Animal Science 48 (5): 469.
This study was performed to evaluate an animal model for the treatment of cutaneous hyperpigmentation, investigate characteristics of pigmented and nonpigmented skin in this model, and to evaluate the effects of hydroquinone on the spotty pigmentation, which is a characteristic of these dogs.
A commercial patch test plaster containing 3% hydroquinone was applied daily for one month to 8 dogs (F2's of MHD X Beagles). Changes in skin color were analyzed by a spectrophometer. Melanocyte counts were taken by incubating biopsied epidermal sheets in dihydroxyphenylalanine (DOPA) and tabulating DOPA positive cells by light microscopy.
After one month of treatment, depigmentation had spread to one quarter of the animals body and by 6 months total cutaneous depigmentation was noted. Treatment did not extend to other sites of normal pigmentation, such as the pigmented cells of the eyes.
Other models used to test depigmenting agents include: B16 mouse melanoma cell line (in vitro), colored guinea pigs, and grey and black moor goldfish.
Questions:
1. If this study were performed in the U.S. would the investigator be allowed to group house the 8 dogs in this study?
2. If these dogs were received from a dealer, what two things must accompany the dogs?
3. Name an in vitro and two other in vivo models used to study cutaneous depigmentating agents.
4. Which of the following is incorrect regarding the use of the Mexican hairless dog as a model for testing depigmentating agents versus the colored guinea pigs?
a. unlike guinea pigs, MHDs have a multilayer epidermis
b. melanocyte distribution in MHDs is more similar to human melanocyte distribution.
c. MHDs do not require pre-treatment with a photosensitizing agent and ultraviolet radiation.
d. unlike guinea pigs, depigmentation of MHDs by hydriquinone is reversible
e. MHDs develop hyperpigmentation spontaneously by 18 months of age
5. Name the four layers of epidermis found in the dog and humans.
Answers:
1. Yes, according to the Animal Welfare Act a maximum of 12 dogs may be housed together.
2. A health certificate signed within 10 days of shipment and the dogs must have i.d. such as a tatoo or tags.
3. B16 mouse melanoma cell line (in vitro), colored guinea pigs, and grey and black moor goldfish
4. d. unlike guinea pigs, depigmentation of MHDs by hydriquinone is reversible (question was taken from practice exam given at USAAMARID 1/29/99)
5. stratum corneum, granulosum, spinosum, and basale

Genetic Galactocerebrosidase Deficiency (Globoid Cell Leukodystrophy, Krabbe Disease) in Rhesus Monkeys (Macaca mulatta). Laboratory Animal Science 48 (5): 476.
Globoid Cell Leukodystrophy (GLD) or Krabbe Disease is a disorder of the CNS and peripheral nervous system. This autosomal recessive disease results from a deficiency in galactocerebrosidase (GALC) activity, a lysosomal enzyme that catabolizes hydrolysis of galactose from specific galactolipids. This enzyme deficiency results in severely decreased amounts of myelin. In the human these cases become apparent within the first few months of life and progress to death before the second year. The Globoid cells consist of large macrophages and are located around blood vessels in the white matter of the brain. The also contain large amts of glycolipids in the cytoplasm. The mutations that cause GLD have been identified in Twitcher mice, West Highland White and Cairn Terriers. In twitcher mice the peripheral nervous system is mostly affected while in humans the CNS is more affected. This paper notes that the establishment of a breeding colony of heterozygous carrier rhesus monkeys that have produced homozy

Latissimus Dorsi Cardiomyoplasty: A Chronic Experimental Porcine Model. Feasibility Study of Cardiomyoplasty in Danish Landrace Pigs and Göttingen Minipigs. Laboratory Animal Science 48 (5): 483.
The latissimus dorsi is surgically transposed and wrapped around the heart to treat end-stage heart failure by inducing its contraction in synchrony with the heart beat by using a dedicated cardiac-triggered myostimulator. The authors have developed a chronic porcine model of ischemic heart failure. They will study the impact of cardiomyoplasty on those pigs. Pigs are very suitable for experimental evaluation of a variety of aspects related to cardiomyoplasty. Sheep, calves, goats and dogs have been used in the past but pigs have several anatomic and physiologic features that resemble those of humans. Furthermore, ethical and economical concerns are less pronounced for pigs. Landrace and Gottinberg have adequately sized latissimus dorsi to wrapping of the normal nondilated heart. Gottinberg minipigs are suitable substrate for studies of cardiomyoplasty. Next step would study the latissimus dorsi skeletal muscle type II fibers (fast-twitching but fatigue-able) gradually change to slow-twitching fatigue resistant type I fibers after 8 to 12-week training regimen.
QUESTIONS:
1. The latissimus dorsi is more easily dissected in what kind of porcine? Landrace pigs or Gottenberg minipigs
2. How would an electrically stimulated latissimus dorsi function to assist a failing heart?
a- Supplement cardiac vascularization
b- Prevent cellular death of degenerated myocites
c- Provide assisted heart pumping
d- Prevent further dilatation of the heart
e- Change muscle fiber types
ANSWERS:
1. Landrace
2. c & d

Characterization of Platelet Abnormalities of Tester Moriyama (TM) Rats with Storage Pool Deficiency. Laboratory Animal Science 48 (5): 490.
Human platelets possess four types of granules: lysosomes; peroxisomes; alpha granules containing adhesion proteins and growth factors; and dense granules containing serotonin, Ca, ADP, ATP, and pyrophosphate. There are a number of clinical conditions generally termed storage pool deficiencies (SPD) that are associated with a decrease in the number or content of dense granules and by prolonged bleeding times and abnormal aggregation profiles. Among those conditions are tyrosinase positive albinism and Chediak-Higashi (CH) syndrome. This range of conditions suggests that the biogenesis of dense granules, melanosomes, and lysosomes is related. There are a number of animal models for SPD including those with CH-like syndrome and also in some rat and mouse strains associated with certain "dilute" coat colors such as the fawn-hooded (FH) rat and the beige mouse. In this paper, the authors looked at the Tester Moriyama (TM) rat which has a light brown hooded coat and an autosomal recessive bleeding disorder. Although the genetic mutation in the TM rats seems to be different from that in the FH rats, morphological and biochemical studies indicated that the bleeding disorder in this strain is also due to SPD. The authors conclude that the TM rat is a potentially useful model for the study of platelet SPD.
QUESTIONS:
1. Chediak-Higashi like syndromes have been reported in what species?
2. FYI - other mouse strains that may have SPD.
ANSWERS:
1.mice, rats, cattle, cats, minks, foxes, 1 case in a killer whale
2. Hypopigmentation, prolonged bleeding time, and normal platelet numbers with reduced platelet granules have been reported in C57BL/6 mice with the following pigment mutations: bg (beige), pa (pallid), pe (pearl), le (light ear), ep (pale ear), ru-2mr (maroon), and ru (ruby eye). Bleeding time abnormalities in these animals can be corrected by bone marrow transplantation from normal mice.

Evaluation and Characterization of Congenital Hpothyroidism in rdw Dwarf Rats. Laboratory Animal Science 48 (5): 496.
In 1998, a new strain of dwarf rats was found in an inbred colony of Wistar-Imamichi rats. The autosomal recessive trait was given the common name of rdw. Compared with normal euthyroid rats at 10 wks of age, rdw rats have a decreased serum thyroxine (T4) concentration and markedly lower growth hormone (GH) and prolactin values in blood and pituitary gland. Both sexes are infertile. The testicular weight of rdw rats is greater than normal rats after 15-16 wks of age although body weight of rdw rats is less than half that of normal controls.
A variety of dwarf mutant rodents with endocrine defects have been identified. These include; dwarf (dw/dw), Ames dwarf (df/df), little (lit/lit), hypothyroid (hyt/hyt) and cog mice, and SD (dr/dr) and Lews dwarf rats. Congenital hypothyroidism is only present in the hyt and cog mice.
The purpose of this paper was to characterize the rdw rats to determine their potential to be a model of hereditary congenital hypothyroidism.
Normal, rdw and rdw + T4 supplemented litter mates were examined and the results were as follows. At 30-40 wks of age, body weight, Hb, GLU, and systolic blood pressure were significantly lower, and serum values for AST, total cholesterol, total protein and BUN were higher in rdw than in normal rats. Serum concentrations of total T4 and free triiodothyronine were significantly lower, and serum TSH concentration was markedly higher in rdw than in Normal rats. Serum GH concentration was significantly lower in rdw than in normal rats. Results of histologic examination showed that thyroid gland of rdw rats was markedly atrophied, compared to normal. Organs and hematological and biochemical values in rdw rats corresponded to those of the hypothyroid state in humans. Most organ weights, hematologic and biochemical values, blood pressure and serum hormone values underwent substantial restoration toward normal in response to replacement therapy. The authors conclude that the rdw rat is a useful model of congenital hypothyroidism.
Questions
1. Which organ in the rdw rat has a relative weight 2.5 times greater than normal rats?
a. Heart
b. Uterus
c. Testicles
d. Liver
2. The rdw rat is deficient in which of the following serum parameters
a. Growth hormone
b. Total protein
c. Blood thyroxine (T4)
d. a and c
e. None of the above
3. Supplementation of rdw rats with T4
a. restored body size to normal
b. restored organ weights, hematologic and biochemical parameters toward normal
c. Had no effect on any parameters measured
e. None of the above
Questions:
1. T/F: Hypothyroid rats are anemic.
2. Why do hypothyroid rats have high cholesterol?
3. Name a rat strain with hereditary hypothyroidism.
Answers
1. C
2. D
3. B
Answers:
1. True
2. Cholesterol is mainly produced by the liver, and is converted to bile acids. Thyroid hormones accelerate this process. In the absence of thyroid hormones, less cholesterol is converted to bile acids.
3. rdw ("rat dwarf")

Morphologic and Hematologic Characteristics of Storage Pool Deficiency in Beige Rats (Chédiak-Higashi Syndrome of Rats). Laboratory Animal Science 48 (5): 502.
Chediak-Higashi syndrome (CHS) is a rare autosomal recessive genetic disease characterized by diluted color of the hair and eyes, increased susceptibility to infection owing to abnormal functioning of leukocytes containing giant granules, and a hemorrhagic tendency. It has been reported in mink, cattle, killer whales, cats, mice and rats. Affected rats and mice are beige based on their coat color. Humans with CHS experience petechiae, ecchymoses, gingival bleeding, fever, jaundice, hepatosplenomegaly, lymphadenopathy, pancytopenia, bleeding tendency, and neurologic changes. Animals with CHS are thought to have a bleeding tendency related to platelet storage pool deficiency characterized by prolonged bleeding time; impaired platelet aggregation, lower platelet concentrations of ADP, ATP, serotonin, & Ca; deficiency in dense granules. Goal was to characterize platelet aggregation, dense granule contents and ultrastructure of platelets in beige rats. Beige rats (DAbg/bg) are mutants on a DA background. Both DA and Wistar rats were used as controls. Blood was collected in citrate for platelet counts and in heparin for aggregation studies. There was no evidence of spontaneous hemorrhage or difference in platelet counts in the beige, DA or Wistar rats. In response to collagen, platelets of Wistar and DA rats aggregated normally but beige rats did not aggregate at all. Maximal aggregation in response to ADP as 80% and disaggregation occurred more rapidly for beige rats when compared to Wistar or DA's. Platelet ADP and serotonin was lower for beige than Wistar and DA rats. Platelet ATP levels for beige rats were the same as Wistars but 2/3 of DA rats. Platelets from beige rats had the same ultrastructural findings except frewer dense granules. Owing to the impaired platelet aggregation and platelet biochemical and morphologic characteristics, the beige rat with Chediak-Higashi syndrome is a new animal model of SPD. The bleeding tendency in humans with CHS is either due to severe thrombocytopenia or SPD associated with CHS.
Questions:
1) Which is the best anticoagulant for evaluating rat platelet aggregation:
a) citrate
b) heparin
c) EDTA
d) none
2) Platelet aggregation is studied turbidimetrically using platelet rich plasma and a __________(instrument).
Answers:
1) b heparin
2) Hematracer

Sheep Model for Study of Maternal Adrenal Gland Gunction During Pregnancy. Laboratory Animal Science 48 (5): 507.
Authors goal was to develop a model for the study of maternal adrenal gland regulation and the effects of maternal cortisol secretion on fetal homeostasis. Sheep were chosen due to large fetal size and accessibility; high success rate of ovine fetal surgical preparation: predominance of single or twin fetuses; and the relative cost effectiveness of sheep, compared with primate models. The ovine model is also used because many components important for initiation of parturition are known including the central role of the adrenal gland. At about 108 days of gestation, before the time of rapid fetal growth or fetal adrenocortical maturation, ewes were adrenalectomized. Ewes were then infused with aldosterone to induce normal late-gestational aldosterone concentrations. Ewes were also treated with cortisol levels that induced plasma levels associated with stress for 2 days followed by reduction to levels similar to normal late-pregnant ewes or nonpregnant ewes. Difficulties encountered included postoperative paresis due to poor positioning during surgery. Morbidity and mortality was also associated with interruption of infusion of aldosterone and cortisol due to failure of catheters and steroid pumps. With proper steroid replacement, plasma protein, electrolyte, and glucose concentrations in adrenalectomized ewes were not different from those in the sham-operated ewes. Of the 9/11 ewes surviving to parturition, two aborted fetuses, three ewes each delivered one live and one dead fetus, two delivered live singleton fetuses and two delivered twins.
Questions:
1. When does the fetal sheep adrenal gland mature and begin producing steroids?
2. In sheep, what triggers parturition?
Answers
1. approximately day 125
2. Parturition is initiated by an increase in the activity of the fetal hypothalamic-pituitary adrenocortical axis. Increases in ovine fetal cortisol concentration initiate labor by inducing cytochrome P450c17 in the placenta. This enzyme has 17-hydroxylase and 17,20-lyase activities; therefore, induction of this enzyme increases the estrogen-to-progesterone ratio and augments uterine contractility.

Plasma Electrolyte and Metabolite Concentrations Associated with Pentobarbital or Pentobarbital-Propofol Anesthesia During Three Weeks' Mechanical Ventilation and Intensive Care in Dogs. Laboratory Animal Science 48 (5): 513.
The authors used pentobarb, propofol, or a combination to deeply sedate 17 clinically normal dogs and maintain them on ventilation and liquid nutritional supplementation (via nasogastric tube or parenterally) for three weeks. Neuromuscular blocking agents were administered to 9 of the dogs, so that ventilation was required. Mortality was 47%, with death occuring between days 2 and 18. Tolerance developed to both drugs. The pentobarb-propofol combination was superior to either drug alone, and required minimal interventions by ICU personnel. The stated aim of the paper was to determine if prolonged anesthesia altered values for plasma electrolytes, PTH, blood gases, and metabolites. They found that these values generally remained stable except in those dogs that developed other problems, e.g. infection or pneumothorax.
q1: Tolerance develops to
a) prolonged anesthesia with pentobarb
b) prolonged anesthesia with propofol
c) all of the above
d) none of the above
q2. electrolyte values in healthy dogs sedated for long periods without complication
a) remain stable
b) fluctuate
c) gradually increase showing hemoconcentration
d) gradually decrease showing hemodilution
A1. c
A2. a

Effects of Water Dilution, Housing, and Food on Rat Urine Collected from the Metabolism Cage. Laboratory Animal Science 48 (5): 520.
The authors of this study investigated 3 factors that affect the amounts of water consumed and urine collected in the metabolism cage. They are water dilution, housing and food. It was found that the leakage from the sipper tube have very little affect. They also found that rats housed individually in wire caging before being placed in the metabolism cage can consume more water and inturn excrete more urine than rats housed in groups in solid bottom cages. It was also found that when food was provide during urine collection rats consumed similar amounts of water but excreted significantly smaller amounts of urine than did rats without food.
No questions

Antibody Repsonse in Baboons (Papio cynocephalus anubis) to a Commercially Available Encephalomyocarditis Virus Vaccine. Laboratory Animal Science 48 (5): 526.
Encephalomyocarditis viruses (EMCV) are classified as cardioviruses and are in the Picornaviridae family. These viruses are know to cause disease in a large variety of animals including, baboons, swine, and zoo animals. Outbreaks of this virus can be severe and with the potential use of organs for enotransplantations from both swine and baboon, development of effective prevention strategies is necessary. The source of infection is believed to be ingestion of contaminated food and water by wild rodent carriers. An outbreak in Texas (SFBR) killed approximately 80 animals with no clinical disease prior to death. Gross pathology was consistent with congestive heart failure and histologically their was indication of myocardial degeneration and necrosis.
EMCV vaccine marketed for swine use was administered for this study. It was an oil-and-water based inactivated vaccine. Two injections were given at a 21 day interval in the lateral thigh muscle. Concurrent tetanus antitoxin was given to each animal to ensure that they were able to mount an immune response. Five of six animals had a positive titer at 1:20 or greater after EMCV vaccine administration. Based on previous work in which animals were vaccinated, developed positive titers, subsequently challenged, and were protected the animals from this study were not challenged. Mengo virus, a cardiovirus serologically related to EMCV, when adapted into a vaccine was also protective against EMCV.
This study concluded that 5 of 6 baboons vaccinated with the swine EMCV vaccine developed pos. titers at 3 months which persisted up to 6 months post vaccination.
Question
1. What family does the EMCV belong.
2. Describe the gross pathologic lesions associated with an ecephalomyocarditis?
3. How is the disease transmitted?
4. Name two species used for xenotransplantation?
Answers:
1. Picornaviridae
2. Congestive heart failure
3. Ingestion of contaminated food or water ( spread by wild rodents )
4. Swine and baboon

The Ferret as a Model for Myocardial Infarct Size Reduction by Use of a Selectin Inhibitor. Laboratory Animal Science 48 (5): 529.
Leukocyte adherence and activation during reprofusion play a major role in determining size of postischemic infarct. Selectins mediate initial rolling and attachment of leukocytes to vascular endothelium during early phase of an inflammatory response. Selectin inhibitors have been shown to reduce infarct size and neutrophil accumulation in dogs and cats. However, no single species has been found to be predictive for humans with respect to infarct size. In this paper ferrets were used as a model of coronary artery occlusion and reprofusion.
The left anterior descending coronary artery (LAD) was occluded for 90 min. to create infarcted area. 2 mins. prior to reprofusion (88 mins after occlusion), selectin inhibitor was injected to study effect on leukocyte adherence and activation. Reprofusion lasts for 5 hrs then the LAD is reoccluded and Evan's Blue dye was injected to stain all profused areas. The left ventricle (LV) was harvested and the unstained area (area at risk=AR) was dissected away and placed in 1% triphenytetrazolium chloride (TTC). Positive staining with TTC (deep red) represented the viable tissue within the AR. The remaining unstained tissue was the infracted area (IA).
The evan's blue stained, TTC-stained and unstained tissues were weighed. The LV mass was the sum of all 3. AR=TTC + unstained. Infarct size was expressed as % of LV mass (IA/LV x100) and % of AR (IA/AR x 100).
Important: It was determined that %AR (IA/AR x 100) was a better measurement that %LV (IA/LV x 100) because even animals of the same species have different coronary artery anatomy and different perfusion areas. Thus there is more variability in %LV and requires more measurements and more animals to show significant differences.
Using IA/AR (but not IA/LV) a reduction of 38% was noted in the selectin inhibited group.
Questions:
1. Which is a better measurement of infarcted area, % LV or % AR.
2. T/F Selectins have been shown to decrease infarcted area in the dog, cat and ferret?
3. In this model, does deep red staining in the AR with TTC represent viable or dead tissue?
Answers
1. %AR because it is not affected as much as %LV by the variability of blood supply.
2. T
3. Viable tissue (could not easily find what this stain is binding)

Postnatal Blood Cell Counts of Japanese House Mice (Mus musculus molossinus): Maintenance of Low Numbers of White Blood Cells. Laboratory Animal Science 48 (5): 533.
Mus musculus molossinus, commonly called molossinus mice, is a subspecies of the house mice that inhabits Japan as a wild population. They have been mainly used in genetic studies and were found to have great differences in their DNA sequences, compared with those of common laboratory mice.
The study determined representative hematologic parametres as red blood cells RBC, white blood cells WBC and hematocrit HT of molossinus mice in their postnatnal stages at weekly intervals. Molosinus mice and C57BL/5N and BALB/cA were used in tis study.Blood was obtained from retroorbital plexus in mice in 3 weeks old mice and by decapitation in newborns (less than 2 weeks).
RBC and HT were no significant differences between the molossinus and other mice at any age.
The most remarcable differences in WBC count was at and after 5 weeks of age because WBC count in the laboratory mice increased greantly but not in molossinus mice (27, 74 and 66 10E2cells/ ml in molossinus BALB and B6). Monocyte and eosinophil numbers were not significant differences but the number of neutrophil anb lymphocyte was lower in molossinus mice than in common laboratory mice. Molossinus mice had a low count of WBC but it can not be regarded as leukopenia because these mice have a normal lifespan and breeding abilitis.Thus, molossinus mice might have a distinc hematopoietic nature.
QUESTIONS
1.- Why are molossinus mice used in research?
2.- F/T WBC is a neutrophil, lymphocyte, eosinophil and monocyte count
3.- Molossinus mice have low numbers of RBC
ANSWERS
1- Genetic studies
2.- T
3.- F

Changes in Electrical Impedance of Vaginal Mucus During the Menstral Cycle in Cynomologus Monkeys (Macaca fascicularis). Laboratory Animal Science 48 (5): 535.
Changes in electrical impedance of the vaginal mucosa (EIV) may indicate changes in the properties of the vaginal mucus. This has already been reported for cows, pigs, sheep and rhesus. This paper documents changes in EIV and correlates it with estradiol and progesterone levels in cynos.
In 12 cynos, regular cycles were established prior to EIV measurements. The EIV measurements were taken at 2-3 day intervals for 30 days. Blood samples were collected prior to the EIV measurements. Results show that the EIV values did not correlate with the estradiol values, but were highly correlated with the progesterone values. This is in opposition to the changes seen in rats, where the increase in EIV is correlated with an increase in estradiol.
Three additional monkeys were treated with equine chorionic gonadotropin and human chorionic gonadotropin (eCG on days 3,5,7,9 and 11 followed by hCG on day 11). Follicles were aspirated 28 hours post hCG injection. EIV measurements were taken on the same day as the injections as well as the day of follicular aspiration. Data suggests that hormone treatment enhanced the changes in estradiol and progesterone concentration and EIV values were increased two-fold over untreated monkeys. The correlation between increased progesterone and increased EIV values still held.
Changes in the chemical composition of the vaginal mucus during the estrous cycle may be induced by estradiol and/or progesterone. Therefore, differences between rats and cynos may reflect differences in formation of the corpus luteum. Since observation of sex-skin swelling is not a reliable indication of estrus in cynos, changes in EIV may be used as a reliable indicator of the luteal phase.
Questions:
1. Changes in EIV may be associated with:
a. increases in estradiol
b. increases in progesterone
c. neither of the above
d. both of the above
2. Increases in EIV have been measured in: (indicate all which are correct)
a. rats
b. rhesus
c. pigs
d. sheep
e. cows
f. dogs
g. cats
3. In cynos, increased EIV values are associated with increases in :
a. estradiol
b. progesterone
c. no clear correlation has been associated
Answers:
1. d
2. a,b,c,d,e This report is the first documenting such correlation in cynomolgus monkeys.
3. b

Intraduodenal Inoculation of Adult Rabbits for Evaluating the Immunogenicity of Genetically Attenuated Vibrio cholerae Strains. Laboratory Animal Science 48 (5): 538.
Intraduodenally inoculated adult NZW rabbits are used to evaluate the immunogenicity of various genetically attenuated cholera strains during vaccine development. The ligated ileal loop model is successfully used in the evaluation of V. cholerae strain pathogenicity and cholera toxin action.
For the intraduodenal inoculation model, a midline laparotomy was performed on anesthetized rabbits. The duodenum was exteriorized, 5 ml (109 CFU) bacterial suspension was injected into the lumen, and the incision closed. Atropine was administed one hour later to prolong inhibition of intestinal motility. Antibacterial antibodies were measured by ELISA on days 0, 7, 14, 21 and 28. Serum vibriocidal antibody titers were measured by microassays on days 0, 14, 21 and 28. Antibodies were present (after day 0) in all assays. The goal of these studies is to develop an attenuated cholera strain that will, after oral administration in humans, induce protective antibody production without being pathogenic.
Questions:
1. What does the rabbit ligated ileal loop model evaluate? Answer: Vibrio cholerae strain pathogenicity and cholera toxin action.
2. True/False: The germfree mouse model for measuring immune response to cholera is, so far, the animal model that most closely mimics human GI tract physiology. Answer: False--intestinal immune responses in germfree mice are not normal.

Detection of Pasteurellaceae in Rodents by Polymerase Chain Reaction Analysis. Laboratory Animal Science 48 (5): 542.
The family Pasteurellaceae consists of the genera Pasteurella, Actinobacillus and Hesmophilus. Pasterurella pneumotropica is considered the most often pathogenic member of this family.Animals infected with these organisms are usually asymptomatic carriers harboring few bacteria in their respiratory or genital tract.
Diagnostic of this bacteria can make using culture isolations ( needs three days and the diagnostic specificity is 70%) or serologic testing (recommemded animals older than 12 weeks). The authors believe that there are others members of the Pasteurellaceae may also be of importance for laboratory animal medicine and they may influence biomedical research. The investigation was carried out using animals from their routine health-monitoring program ( 35 mice, 23 rats, 2 gerbils, 20 syrian hamsters and 1 rabbbit). The trachea was laid bare and incision was made, and a swab was inserted throught this incision. Swab specimens were incubated and the plates were examined for colonies morphologically typical for the Pasteurellaceae. Pharynx, trachea and lunh specimens were collected for DNA extration.Twenty four strains of Pasteurellaceae from German Cancer Reserach Center were the positive control. They concluded that their PCR assay was 30% more sensitive than the culture isolation method and reduces the turnaround time (culture isolation requieres a minimum of three days and detection using this PCR takes 5h). PCR is more specific than serologic testing, without limiting testing to a certain age group.
QUESTIONS
1.- Where must a swab inserted to collected for culture isolation of Pasteurellaceae?
2.-Name of the most pathogenic member of the Pasteurellaceae in rodents?
ANSWERS
1.- trachea or pharynge
2.- Pasteurella pneumotropica