Microenvironment in Ventilated Animal Cages with Differing Ventilation Rates, Mice Populations, and Frequency of Bedding Changes. Contemporary Topics 37 (2): 43.
PURPOSE:
Assess the microenvironment in separately ventilated mouse cages at differing ventilation rates, mice population, and frequency of bedding changes using intracage temperature, relative humidity, and concentrations of ammonia and carbon dioxide as measurable parameters.
EXPERIMENT 1:
Ventilation rates of 30, 40, 60, 80, adn 100 air changes/hour were evaluated for male mice in groups of 4. For all rates ammonia concentration was less than 3ppm, CO2 concentration ranged from 840-3300ppm, relative humidity ranged from 42-65%, and temperature ranged from 23.2-25.3 degrees C.
EXPERIMENT 2:
Bedding in cages containing male mice (4/cage) and ventilated at 60 changes/hour was not changed for 26 days. Ammonia concentration did not exceed 10ppm adn relative humidity did not exceed 45%.
EXPERIMENT 3:
Ventilation rates and frequency of bedding changes in ventilated cages containing breeding trios (2 females/1 male) with pups were tested. Ammonia concentration stayed at 25ppm or less for 30, 60, and 100 air changes/hour with bedding changed every 2 weeks.
CONCLUSION:
30 air changes/hour is sufficient for health in male mice housed 4/cage with bedding changed weekly
60 air changes/hour is necessary when housing male mice in cages in which bedding is changed every 2 weeks
100 air changes/hour is necessary for cages housing breeding trios and pups that are changed out every 2 weeks
Questions:
1. What are PIV cages?
2. What is the primary source of ammonia in rodent cages?
3. What is a factor which encourages ammonia production?
Answers:
1. pressurized individually ventilated cages
2. conversion of urea to ammonia by urease which is endogenous in some bedding and produced by urease-positive bacteria
3. increased humidity

Effectivness of Rack Sanitation Procedures for Elimination of Bacteria from Automatic Watering Manifolds. Contemporary Topics 37 (2): 50.
The article evaluated the post-sanitation microbial contamination of experimentally inoculated racks and racks you house conventional mice. Three sanitation protocols were used: rack-washer without manifold flush, rack washer with the manifold flush, and rack washer with flush followed by autoclaving. The results showed that the sanitation with or without the manifold flush was ineffective with total of 43 % positive for bacterial contamination. It indicated that steam sterilization is necessary to for elimination bacteria from automatic watering systems. It was also found that a greater proportion of the conventional racks were contaminated as compared to the experimentally inoculated racks (79%vs18%). This supports that bacterial contamination via the automatic watering manifold is a valid possibility. This supports the conclusion that racks should be steam sterilized especially with the increase in the amount of immune-incompetent animals currently being used that may be getting inoculated with bacterial pathogens though the automatic watering systems.
No questions

Determination of Optimal Angles for Intraoral Occlusal Views for the Radiographic Imaging of Dental Structures in the Cynomolgus Monkey (Macaca fascicularis). Contemporary Topics 37 (2): 52.
This article describes the proper techniques to use when radiographing the teeth of Cynomologus monkeys. They found that the best way to isolate the tooth structures of the canine, premolar, and molar teeth of both arcades was to direct the primary beam 60 degrees relative to the hard palate in the transverse plane. A DV view was useful for examination of the maxillary incisors, whereas a VD view was useful for examination of the mandibular incisors. A useful table is included in this article.
Questions:
1. What are the most commonly seen dental abnormalities of NHP?
2. What is the dental formula for cynomologus monkeys?
3. What is the scientific name for cynomologus monkeys?
4. What is a bisecting angle technique (as used in dental radiographs)?
Answers:
1. Fractures, caries, and periapical abscesses
2. 2/2, 1/1, 2/2, 3/3 = 32 (2)
3. Macaca fascicularis
4. The bisecting angle technique involves direction of the primary beam perpendicular to the line that bisects the angle formed by the film and the long axis of the tooth. This produces true images of length despite oblique projections.

Evaluation of Rainbow Trout as a Model for use in Studies on Pathogenesis of the Branchial Microsporidian Loma salmonae. Contemporary Topics 37 (2): 55.
Loma salmonae is a gill microsporidian pathogen causing significant economic loss of pen-reared Chinook and coho salmon (Oncorhynchus tshawytscha, O. kisutch). Ingested parasites cross intestinal mucosa, enter systemic circulation and develop in the vasculature of the gills to form large spore-laden xenomas. Because Chinook and coho salmon are difficult to work with in laboratory studies (become diseased and die) rainbow trout (O. mykiss), brook trout (Salvelinus fontinalis), Atlantic salmon (Salmo salar) and Arctic charr (Salvelinus alpinus) were evaluated as a model. Rainbow trout were permissive to the growth and maturation cycles. Could not transmit organism to Salvelinus or Salmon species. L. salmonae may be species specific to Oncorhynchus. Rainbow trout do not develop clinical signs but do develop the characteristic xenomas and multifocal granulomatus branchitis, of the central venous sinusoid of gill filaments. Since unable to infect fish housed in water at 10 degrees C, water temperature may be a common promoting or limiting factor.
Questions:
1. What is the histopathological lesions seen in fish infected with Loma salmonae?
2. What is the genus of Chinook salmon, coho salmon and rainbow trout?
3. T/F Rainbow trout and brook trout in the same genus?
Note: Salmon - of the genera salmon and Oncorhynchus
Answers
1. Xenomas followed by multifocal granulomatus branchitis of the central venous sinusoid of the gill filament
2. Oncorhyncus
3. Brook trout are in the genus Salvelinus

Use of Chlorine Dioxide for Antimicrobial Prophylactic Maintenance of Cephalic Recording Devices in Rhesus Macaques (Macaca mulatta). Contemporary Topics 37 (2): 59.
Chlorine dioxide (Clidox-s) is a broad spectrum, oxidizing disinfectant which is relatively non-irritating to skin and ocular tissues. The recommended chlorine dioxide solution used in this article was prepared as a 1:5:1 (base: tap water: activator) - the 1:18:1 strength was not recommended. During a 4 week study, the 1:5:1 chlorine dioxide solution was used on days 2 to 4, and the antibiotic solutions, cefazolin sodium 100 mg/ml, were used on days 1 and 5 in the cylinder chamber weekly. Few or no bacterial or mycotic colonies have been recovered during weekly culturing. Cleaning the exterior of the cranial implants with 70% isopropyl alcohol prior to opening the seal also eliminate the microbial load which might serve as a potential source of implant contamination. One thing to keep in mind is that chlorine dioxide may cause corrosion of the cylinder. Chlorine dioxide alone failed to control bacteria in vivo; antibiotics alone failed to eliminated the fungal infection.
Organisms most commonly recovered from the interior of the cylinders were Candida sp, Trichosporon sp, and coagulase-positive Staphylococcus sp.
Extra points: Streptococcus is catalase negative. Staphylococcus aureus is catalase positive and coagulase positive.
No questions

Procedure for Successfully Introducing Cesarean-derived Rhesus Monkey (Macaca mulatta) Infants to Their Mothers. Contemporary Topics 37 (2): 64.
Cesarian deliveries of rhesus macaques is a common procedure as a part of many experimental protocols. Previous reports state that up to 97% of mothers fail to accept their infants post-operatively. Procedures used to introduce the infants included first placing the infant in a box in a cage adjacent to the mother for visual inspection prior to physical re-introduction. After placing the infant in the cage,If the mother did not pick up the infant within 2 hrs, the introduction was terminated and attempted the subsequent day. Other procedures involved anesthetizing both the infant and mother and placing both in the same cage. These authors developed a systematic protocol for introducing cesarean-delivered infants to their mothers.
Laparotomy pads saved from surgery were used to 'scent' the infant with maternal fluids. A clean towel was placed in the mother's cage during her recovery. Once the mother had recovered from anesthesia, the infant was placed in the mother's cage. If the mother didn't allow the infant to suckle within an hour, the towel and infant were removed to the nursery overnight. Daily attempts at introduction continued until successful, or the safety of the infant was compromised. Success rates by the end of 3 days were 72%. It was noted that all successful attempts were with females with previous vaginal deliveries and successful rearing of at least one infant.
Questions:
1. The key factors for acceptance of an cesarian-derived infant by the mothers include:
a. Maternal parity
b. Olfactory cues
c. Repeated exposure
d. Stable environment
e. all of the above
Answer:
1. e

A Novel Ventilated Transport Container for Transporting Laboratory Animals. Contemporary Topics 37 (2): 69.
A novel ventilated transport container was developed to allow safe transport of laboratory animals among biocontainment areas, conventional animal holding areas, or laboratories. This specialized device allowed simultaneous transport and concurrent isolation of 2 nonhuman primates carried in standard transport boxes as the primary enclosure. Its use substantially reduced the risk to the primates by eliminating the need for anesthesia during transport between containment areas and, additionally, improved the margin of safety during transport. The device was easily decontaminated and was also appropriate to transport other small laboratory animals between containment areas.
Summary: Container was made of solid aluminum sheets with handles, latches, and casters screwed into aluminum plates that were welded to the outside walls of the container. The internal volume of the box was 0.36 cubic meters (360 L). The whole container had a mass of 68.8 kg. Ventilation was provided by single intake and exhaust ports. A battery powered motor unit (the assumption is this is a fan) on the exhaust port creates in the container negative air pressure as compared to the outside. High efficiency particulate air filters were placed on the intake and exhaust ports. Using a Gilibrator bubble generator with a test range of 2 to 30 L air/min., mean air flow was measured at 15 L/min. Using a volume of 360 L, air changes within the container would be 2.5/h. The minute volume of an unanesthetized Macaca mulatta of 3.6-4.5 kg is 1.5L/min. Therefore, one rhesus would need an air volume of 90L/h. The unit's volume (360 L) provides sufficient air volume for 2 rhesus nonhuman primates (180 L) for 60 min. This container has been used to transport rabbits and rodents as well.
Questions:
1. What is one device to measure air flow?
2. What are high efficiency particulate filters?
3. Does the animal welfare act regulate ventilation requirements for transport containers of nonhuman primates?
Answers:
1. Gilibrator bubble generator.
2. Also called HEPA filters. Filters capable of removing 99.9% of all particles greater than 0.3 micrometers in diameter.
3. Yes, on p.80. It states that ventilation openings must be present on either both or all four walls of the container. If only on two walls, the holes must represent 16% of the total surface area of the wall. If on all four walls, the holes must represent 8% of the total surface area of the wall. All holes must be above the midline of the wall.

Chronic Use of Propofol for Multiple Minor Procedures in the Rabbit. Contemporary Topics 37 (2): 71.
It has been difficult in the past to determine a safe and short-term anesthetic for minor procedures in rabbits using Propofol (Diprivan). In rabbits, propofol doses of 5-15 mg/kg, injected intravenously, quickly induced loss of consciousness soon followed by rapid, excitement free recovery. A recent study was done which involved injecting 1% carrageenan solution into the right knee of 36 male New Zealand White rabbits to produce an inflammatory arthritis in that joint. The left knee served as a control. The injections were to be done a total of 10 times at a dosage of 10 mg/kg IV. After three carrageenan injections (two weeks after the first injection), all animals were anesthetized with aketamine/xylazine mixture (35/5 mg/kg)IM, maintained on isofluorane and underwent bilateral distal femoral implantation of titanium implants. The main purpose of the study was to evaluate the effect of inflammatory arthritis on bone ingrowth to implant surfaces. Upon each injection of the carrageena into the right
Questions/Answers:
1. What is the main side effect of propofol in rabbits?
2. T/F Propofol is suitable for multiple, brief anesthetic procedures inadult rabbits.
1. Respiratory depression
2. False, Suitable for single, brief, anesthetic procedures during a short period of time

A New Method for Collecting Ultrafiltrate Samples from Sheep, Using Microdialysis Catheters. Contemporary Topics 37 (2): 73.
Use of microdialysis catheters can provide valuable information about the in vivo extracellular milieu by allowing long term collection of ultrafiltrate samples. This paper describs such a system in sheep using a vacutainer tube holder. (must see pictures) Sample recovery rates approach 84%. The devices were mounted over the withers and since sheep sleep in sternal recumbancy they tolerated the device very well without tubing disturbance.
Questions:
1. Give the family genus and specie of sheep.
2. Are sheep perissodactyla ?
Answers:
1. Bovidae, Ovis, aries
2. No

Ganglioneruoma in the Adrenal Gland of a Rat. Contemporary Topics 37 (2): 75.
This article described a case report of a ganglioneuroma in the adrenal gland of a 22 month old Fischer 344 rat. The rat was examined because it was icteric and had lost weight. Following euthanasia, gross examination revealed a large circumscribed, 3 cm tan mass at the cranial border of the kidney. Microscopically, mass was identified as the adrenal gland which contained a large expansile, partially circumscribed, nonencapsulated neoplasm that effaced the medulla and was partially surrounded by a thin rim of compressed adrenal cortex. The neoplasm was composed of individual and well-differentiated ganglion cells mixed with satellite and Schwann cells with a neurofibrillar matrix. A diagnosis of adrenal medullary ganglioneuroma was made.
Large granular lymphocyte lymphoma (leukemia) was also evident in the adrenal gland as well as lymphoid organs such as the spleen, and lymph nodes. Loss of body weight and icterus was most likely associated with the lymphoma.
Ganglioneuroma is rarely seen in rats. A ganglioneuroma can be differentiated from the more common and complex pheochromcytoma as the latter consist of fewer neural components (less than 80 percent of mass) in comparison to a ganglioneuroma. In rats ganglioneuromas can also develop in the central nervous system, pituitary gland, and thyroid gland.
Differential diagnosis for a primary neoplasm of the adrenal gland should include carcinomas and adenomas of the adrenal cortex, and, pheochromcytomas, neuroblastomas and ganglioneuromas of the adrenal medulla.
Pheochromcytoma is the most common neoplasm of the adrenal medulla and has been reported in 19 percent of aged female F344 rats and 6 percent of aged male F344 rats. Ganglioneuromas in rats are rare (less than 1 percent incidence). Ganglioneuromas are benign neoplasms arising from primitive neural crest cells. Ganglioneuromas are usually unilateral and often are large causing displacement of the adrenal medulla and compression of the adrenal cortex. Metastasis has not been reported.
Ganglioneuromas have been detected in sympathetic nerves in hamsters; adrenal medulla, abdominal nerve plexus and spinal ganglion of cattle; ocular ganglion in Indian water buffalo; central nervous system and mediastinal ganglion in dogs; and intestinal ganglion in cats.
QUESTIONS
1. Leukemia is a common syndrome of aged F344 rats.
2. What characteristics differentiate a ganglioneuroma from a pheochromcytoma?
3. What differentials should be considered for a primary mass of the adrenal in a rat.
ANSWERS
1. True
2. Pheochromcytoma contains fewer neural components, is more common.
3. Carcinomas and adenomas of the adrenal cortex; pheochromcytomas, neuroblastomas and ganglioneuromas of the adrenal medulla

Malignant Schannoma of the Lumbosacral Plexus After Streptozotocin Therapy in a Substrain of Wistar Rat. Contemporary Topics 37 (2): 78.
This is a case report from one rat in a group in which diabetes was induced through use of STZ. These rats were part of a fetal rat pancreatic transplantation study. STZ contains the carcinogen 1-methyl-1-nitrosourea and has the capacity to induce a variety of tumors. Clinical signs in this male rat began 9 months after induction of diabetes and transplantation with sudden onset of paralysis of the right back leg. A well-circumscribed hard mass was palpable in the right flank. At post mortem, a retroperitoneal non mobile and encapsulated tumor with prominent capsular vasculature was detected adhered to the right lumbosacral plexus. No metastses were evident. Microscopic exam revealed a cellular spindle-cell tumor with a predominantly interlacing, fascicular growth pattern. The cells had hyperchromatic nuclei with moderate pleomorphism and increased mitotic index. EM showed electron dense neurosecretory granules, prominent endoplasmic reticulum, and no pinocytosis.. Immunohistochemistry was positive for S100 protein. All these findings were consistent with a diagnosis of malignant schwannoma, a malignant peripheral nerve sheath tumor.
Questions:
1. The differential diagnosis of this tumor should have included:
a. fibrosarcoma
b. leiomyosarcoma
c. monophasic synovial sarcoma
d. all of the above
2. What are electron microscopic findings characteristic for neural differentation? Epithelial differentiation?
3. STZ induces production and increased tissue levels of what compound that then leads to increased nucleic acid syntheis, increased fibroblast growth, and possible malignant transformation?
4. What is the name of the bacteria that STZ is isolated from?
Answers:
1. D
2. Neural differentiation features are spindle cells with cytoplasmic processes that are coated with basal lamina. Epithelial differentiation features are intercellular spaces lined by microvilli and desmosome-like intercellular junctions.
3. Guanylate 3,5-monophosphate
4. Streptomyces achromogenes