Alcohol as a disinfectant for aseptic surgery of rodents: crossing the thin blue line? Contemporary Topics 41 (1): 10.
Alcohol has been considered inadequate as a surgical disinfectant because of perceptions of inadequacy of killing of bacterial spores and lack of
efficacy in the presence of organic debris. The NRC Guide discourages the use of alcohol as a chemical sterilant/disinfectant for the preparation of surgical instruments. However, this article points out that spore-forming bacteria are a essentially nonexistent threat for causing postoperative
infection in rats and mice. Furthermore, organic debris can be removed with appropriate effort from soiled instruments by using physical scrubbing (e.g. cleaning with soap and water) prior to the alcohol exposure.
Alcohol is frequently used internationally as a skin and surgical instrument decontaminant during the production of genetically mutant mice. The article makes the point that scientists developing such mice would not imperil production or efficiency by using surgical techniques that did not have a proven record of success.
A key drawback to the use of alcohol as a disinfectant is the length of contact time needed for disinfection. However, the contact time needed to decontaminate instruments likely is shorter when they are first cleaned with soap and water or are otherwise used under aseptic conditions.
In summary, there are more effective and expeditious methods of sterilization or high-level disinfection of surgical instruments that are less
corrosive than alcohol (e.g. autoclaving and hot-bead sterilization). However, if used concomittant with sound aseptic technique, alcohol has an
appropriate role in the preparation of surgical instruments for survival surgery in rodent species.
1. What are some of the advantages associated with the use of alcohol for the preparation of surgical instruments for survival surgery in rodent
species?
2. What factors may contribute to the inoculation of pathogenic spores into a surgical site?
1. convenient and low cost (no special equipment needed), lack of antisepsis-associated drawbacks (proven to be efficacious)
2. The employment of grossly deficient and highly traumatic surgical techniques and/or a substantially impaired host immunity.

Individually ventilated cages: beneficial for mice and men? Contemporary Topics 41 (1): 13.
The objective of this study was to investigate the well-being of laboratory rodents in individually ventilated cages (IVC) by making use of preference tests and a multiple housing test system. This system allowed mice to choose between two cages where to build their nest. Both cages were on the same ventilated rack but differed in ventilation rates, ventilation entry and exit port locations, size of cages, and nesting material. The two cages were connected by a rectangular passage with a swing door.The findings of the study supported the conclusions that mice prefer low intracage ventilation rates (lower than 60 or 100 Air Changes Per Hour [ACH]), larger cages (530 sq.cm. vs. 370 sq.cm.), air supply in the top of the cage (rather than the wall), and nest material over nest boxes. Most commercial IVCs vary from 25-125 ACH. Advantages of IVC's include protection of the integrity of the microenvironment and reducing contaminants and pollutants; reduction of the number of cage changes; and increased housing density. Disadvantages of IVC's include cost, complexity and stress due to noise, heat loss and low humidity.
1. Which of the following are potential benefits of individually ventilated cages?
a. Reduced stress due to bacterial contamination.
b. Increased housing density (more cages/square foot).
c. Consistent noise that suppresses sudden unexpected noise.
d. Mild vibrations that enhance rest.
2. Which of the following statements are true?
a. Mice prefer larger cages with ventilation rates of 60 ACH over smaller cages with static air.
b. Mice prefer nestlets over nest boxes.
c. Mice prefer top air inlets over wall air inlets.
1. a & b
2. b & c

Use of microisolator caging in a risk-based mouse import and quarantine program: a retrospective study. Contemporary Topics 41 (1): 20.
The expanding use of genetically engineered mice has placed increasing demands upon research facilities to import mutant strains from noncommercial sources. This is a retrospective evaluation of developing a quarantine program from 1996 to 1999. Conventional quarantine strategies use relative large amounts of space or require specializrd equipment such as cubicles, isolators and ventilared racks.
Main colony assessment is assessed by semiannual testing of exposure to dirty bedding to imunocompetent sentinel female mice placed on either side of double-sided standard shelf racks. Each room is tested on a semiannual basis; however, the testing schedule has several rooms from different areas of the facility. The second part of the screen is the principal animals which are identified as abnormal. Each sending institution send pertinent colony health momitoring from the room and building or origin. The health data is evaluated by the veterinarian responsible for the quarantine facility. Animals from facilities that there is clear evidence they are from contaminated rooms of origin are diverted to a high -risk containment. On the other hand, animals from facilities which are free of contamination are diverted to a low risk quarantine room. Both of these rooms are not in areas of high traffic. The shipping crates are sprayed with a chlorine dioxide-based disinfectant as they are placed in a HEPA-filtered changing room.
The low-risk rooms had polycarbonate shoebox -style static microisolator cages with hardwood chips for bedding.. Cages are changed once a week in a certified class II biological cabinet which provides a HEPA filtered environment to exclude enviromental contamination when cages are opened and to entrap infectious agents. Care staff wear a uniform, mask and gloves and use chlorine dioxide to disenfect the hood and gloves are changed between orders. Medicated feed containing fenbendazole is alternated with standard rodent chow. The most recently received animals are handled last.
The high-risk Personnel wear isolation jumpsuits with integral hood and booties immediately after entering the room. The animals are handled similar to the low-risk room but this room is equipped with a negative HEPA-filtered hood. Animals may remain in this room for 2 months are longer. Breeding is allowed under most circumstances.
Sentinels are composed of 2 female outbred mice, one which receives 10 grams of dirty bedding at each cage change and the has direct contact with one of the quarntine animals (reverse sentinel sampling). Chronological events during the quarantine period include bedding contact, direct contact, principal testing, and sentinel testing and release after approximately eight weeks. Blood is collected from inhalation anesthetized mice by cardiac puncture. Parasite screening is performed by fecals samples from the colon, cellophane perianal, and skin scrappings. Microbiological samples are taken from the nasopharynx and the cecum and placed on chocolate agar and 5% blood agar. Cecal contents on a slide diluted with saline is examined for protozoa, nematodeadults or eggs. If positive results are confirmed, new shipments are diverted to another room.
There was a total of 390 total shipments with 333 (85%) presumed clean and 57 (15%) suspect. When mites were found, permethrin impregnated bedding materials were used. When one animal was exposed to dirty bedding, there were fewer suspects noted. When exposed to dirty bedding and directly exposed to quarantine animals, a greater number of suspects were found.
1. The primary housing units in this quarantine program were ______________ changed in a __________________?
2. Fewer suspects were missed when what exposure of sentinel animals was employed?
1. Static microisolaters and HEPA filtered changing station.
2. Dirty bedding exposure and direct contact with a principal animal

Plasma homocysteine concentrations in a population of Rhesus monkeys (Macaca mulatta): reference ranges and accompanying plasma concentrations of folate and vitamin B12. Contemporary Topics 41 (1): 28.
Homocystein (Hcy) is a sulfur-containing, nonproteinogenic amino acid that is biosynthesized from methionine as an intermediate in its metabolism to cystiene. It is a sensitive functional marker of inadequate cellular folate and vitamin B12 concentrations. It is recognized as a major independent risk factor for cardiovascular disease in humans. The authors explored Hcy levels in a population of rhesus macaques in order to potentially develop a model for studying human disease. Similar to trends noted in humans, male monkeys had higher Hcy levels than did female animals, pregnant animals had lower values than did nonpregnant ones, and Hcy levels were inversely proportional to plasma folate and vitamin B12 concentrations. However, homocysteine levels in rhesus did not vary consistently with age, whereas they increase with age in humans.
1. Hcy is a sensitive indicator of levels of which two B vitamins?
2. Why would the Hcy levels seen in macaques be more consistent than Hcy levels seen in humans?
1. Folate and vitamin B12
2. Macaques are fed a constant diet with stable levels of B vitamins; human diets are variable and have different vitamin concentrations on a regular basis. Humans also consume other items (e.g. caffiene) and engage in other behaviors (e.g. smoking) that cannot be replicated as easily in the macaque model.

A non-terminal surgical procedure for chronic collection of exocrine pancreatic secretions from unrestrained dogs (Canis familiaris). Contemporary Topics 41 (1): 31.
This study describes the technique to chronically collect exocrine pancreatic secretions in dogs in a 1-3h surgical procedure. A small catheter is implanted into the accessory pancreatic duct and a y-shaped second catheter is fistulated into the duodenum. A BiteNot collar and a special jacket protected the exteriorized catheters and exocrine pancreas secretion was either collected into a vial or re-entered into the duodenum. Complications in collecting pancreatic secretion included retrograde contamination with duodenal fluid, including ascending pseudomonas infections especially during slow fluid production, formation of flocculent deposits that occasionally occluded the pancreatic catheter, and removing of the catheters by the unrestrained dogs despite precautions and regular checks. Exocrine pancreatic secretion stopped in both dogs after several weeks suggesting, that the exocrine pancreas was drained through alternate ducts to the duodenum.
a. What are the three basic surgical techniques to allow for chronic collection of exocrine pancreas secretions?
b. Dogs have two pancreatic ducts, the ductus pancreaticus major and the ductus pancreaticus accessories. T or F
c. Quality and quantity of exocrine pancreas secretions correlate with the type of dog food fed to dogs. T or F
a) (1) Pouches prepared from a section of duodenum which contains the minor duodenal papilla, (2) The Thomas procedure, involves preparing a large-diameter cannula through a permanent fistula in the duodenum giving access to temporarily intubate the minor duodenal papilla. (3) Construction of a re-entrant two-catheter system with an exteriorized permanent catheter into the accessory pancreatic duct and a y-shaped larger exteriorized catheter into the duodenum
b) True, however in 30% of the cases, the ductus pancreaticus accessories branches into several ducts and coalesces into the papilla pancreaticus minor.
c) Inconclusive. In this study, with n=2 the ability of dogs to adaptively modulate secretion of exocrine pancreas was inconclusive.

A minimally invasive percutaneous technique for jugular vein catheterization in pigs. Contemporary Topics 41 (1): 38.
Pictures of landmarks within publication should be put into memory.
Good technique paper.
Pigs are increasingly used in CV research because of similarities to human anatomy and comparative hemodynamics and coagulation.
Central venous access indications are
1. used in monitoring and treating clinical/research cases
2. indicated with long-term infusion of hypo-/hypertonic, irritating/high K+ solutions, or when peripheral vessels are inaccessible.
3. indicated for measuring central venous pressure, pulmonary artery (wedge-pressure), or long-term venous access
Advantages of percutaneous vs cutdown:
1. Less post-operative care
2. Less pain
3. Less invasive
4. Non-surgical anesthetics can be used- hypnotic agent, like propofol, are sufficient for percutaneous. Cutdown requires surgical anesthesia.
Anatomy facts:
Maxillary and linguofacial veins form the external jugular vein, which extends caudally until it converges with the subclavian vein to form the brachiocephalic vein. The external jugular vein runs roughly from near the angular process of the mandible ventrolaterally and caudally toward a point just lateral to the thoracic inlet.
This paper describes the anatomic landmarks used to perform guidewire-assisted vascular cannulation in the Yorkshire Pig.
They are:
1. Medial to the mastoid part of the cleidocephalicus muscle-running from the cranial humerus to the mastoid process.
2. Lateral to the mastoid part of the sternocephalicus muscle-running from the sternum to the mastoid process.
3. 1.5 cm lateral and parallel to a line drawn from the angular process of the mandible to the manubrium.
4. Lateral to the C6 ventral spinous process
5. Insertion point-point midway between the manubrium and a line drawn between the two angular processes of the mandible and along the expected path of the jugular vein.
External jugular vein 2-3 cm beneath the skin's surface. 30o angle for insertion. Catheter sizes: either a 7-F triple lumen catheter, or 16 G X 8 in. single lumen or central venous catheter.
Potential complications: arterial catheterization or pneumothorax.
What is the Seldinger method used for?
a. fracture fixation
b. bile duct cannulation
c. central venous catheterization
d. kidney transplantation
c. central venous catheterization

Otitis interna as a result of Pasteurella multocida infection in a laboratory woodchuck (Marmota monax). Contemporary Topics 41 (1): 43.
A laboratory woodchuck presented clincially with left-sided torticollis and a purulent within the external auditory meatus of the left ear. Bacterial culture revealed Pasteurella multocida. Necropsy confirmed otitis media, but not otitis interna. First reported case in a woodchuck.
1. Besides Hepatitis B virus, what have woodchucks been used as models for?
2. Name a clinical sign of otitis media.
3. Name three clinical signs of otitis interna.
4. What is labryrinthitis?
1. Obesity and energy balance; endocrine and metabolism function, central nervous system control mechanisms; cardiovascular, cerebrovascular, and neoplastic disease.
2. Asymptomatic (rubbing at ear, loss of appetitie)
3. Torticollis, nystagmus, ataxia
4. otitis interna

Chronic restraint via tail immobilization of mice: effects on corticosterone levels and other physiologic indices of stress. Contemporary Topics 41 (1): 46.
This study examined physiologic indices of stress (corticosterone levels, body weight, thymus/adrenal/spleen weights) in mice chronically restrained using an established method (tail restraint). This was undertaken to determine if the method produced significant stress as a form of chronic restraint, an issue directly related to animal welfare. The technique of chronic venous cannulation is widely accepted and used for repeated blood sampling or continuous IV infusion of substances. Mice 8-10 weeks of age were randomly assigned to either one of 4 restraint (2 days, 5 days, 8 days, 12 days) groups or non-restrained controls. Restraint was by partial immobilization, passing the tail through the grids of a wire bottom floor and taping the tail to a wooden splint secured to the bottom of the cage. Mice were sacrificed at the end of the restraint period by cervical dislocation followed by exsanguination and blood/tissues were collected. No significant differences were noted within the time intervals between restrained and unrestrained mice when evaluating corticosterone levels. Levels peaked on 8 days of restraint and declined thereafter. Mice in all experimental and control groups lost weight with the only significant difference between restrained vs. unrestrained at the initial time point of 2 days restraint. Spleen, thymus and adrenal weights did not vary significantly across time or between groups. Results of data showing declining corticosterone levels by day 12 indicate a habituation by the animals to the restraint method.
1. What issues should an IACUC consider when faced with a request to use chronic restraint?
2. What is an alternative method of restraint?
1. a. what is the minimum period of time needed for restraint in order to accomplish the research goals,
b. what are the proposed time intervals for observation of the restrained animals,
c. are there any potential physical or physiologic factors that might compromise the animals' well-being during the period of restraint.
2. Tethering. The authors determined that this method was unacceptable for the intravascular and/or intragastric studies planned.

Perineal swellings in two strains of mice. Contemporary Topics 41 (1): 51.
Seven adult male mice of two different strains SSIN/UTSP (inbred strain that is sensitive to carcinogens) and transgenic in FVB background for the human Hmgic gene under the control of an estrogen responsive promoter) and from two different animal housing facilities were submitted for necropsy to evaluate unilateral or bilateral swellings in the ventral perineal area. In this facilities, incidence rates of perineal swelling were estimated to de 2% for SSIN mice and 7% for tg mice. Except for the swellings, the mice seemed normal in regard to appetite, behaviour, activity level and clinical appearance. They were housed in sterilized microisolation cages and were negative for the 13 pathogens tested. On dissection the swellings were oval to spherical cystic structures located near the base of the penis (unilateral and measured 5-12 mm in SSIN, bilateral and measured 8-10 mm in tg). Larger cysts (>10mm) were firm, tan and filled with clear, yellow fluid and smaller cyst were spfter and filled with white amorphous, marbled material. On histopathologic evaluation, cystic structures filled with fluid were lined by flat-tened cuboidal to low columnar epithelial cells with foamy cytoplasm and were skeletal muscle encapsulation. Acinar structures with papillary projections were present in the lumens of some cyst. Some ISSN a plug of similar denser granular material was present in the lumen of the penile urethra near the interface with the cyst. The diagnostic was cystic bulbourethral or Cowper's glands. The paired bulbourethral glands of the mouse are pear shaped, 2-3 mm in diameter, located near the base of the penis and embedded in the bulbocavernosus muscles. Possible causes of bulbourethral gland enlargement in mice included congenital malformation (unlike because all affected mice were adults), hormonal influences (unlike because the authors did not see histopathologic lesion related with exogenous estrogens effects) local trauma and infection, neoplasia (histopathologic no evidence), infection ( no bacterial growth was observed), genetic predisposion ( could have played a role however, five different strains were been reported), environmental factors ( unlike with two different housing), obstructive process ( possible, they found granular material in bulbourethral gland duct and the urethra in 3 mice but this material was found in normal mice too). The authors did not find the ultimate cause of the cyst bulbourethal glands in these mice.
1. F/T Cyst bulbourethal glands have a genetic predisposition
2. F/T The cyst were bilateral and larger in tg
1.- F.
2.- T