2011 Summer Externs

Extern: Tara Martin, ASLAP Foundation Summer Fellowship

• Currently a student of. Virginia-Maryland Regional College of Veterinary Medicine (VMRCVM), Blacksburg, VA to graduate in 2013.

• Involved with clubs such as ASLAP, Student Member of the American Association of Public Health Veterinarians Food Animal Practitioners Club, Public Veterinary Practice Club, SCAVMA, Student Member, Maryland Veterinary Medical Association Student Member, Virginia Veterinary Medical Association, Member, Student Chapter Veterinary Emergency and Critical Care Society Pathology Club, VMRCVM

Mentor: Judy Hickman-Davis , DVM, PhD, DACLAM , Director, Laboratory Animal Training Program, ULAR; Associate Professor, Clinical Veterinary Preventive Medicine Dr Hickman-Davis is an Attending Veterinarian for OSU facilities and as the Director; Quality Assurance Lab Large ensures the health of the animals used in research at OSU. She is the Director for the Laboratory Animal Residency Program. She is a member of ASLAP and AALAS, serves on the IACUC at OSU. Research Project: “Effects of Air Flow on Ammonia Levels in IVC Rat Cages” of Air Flow on Ammonia Levels in IVC Rat Cages

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Effects of Air Flow on Ammonia Levels in IVC Rat CagesLevels in IVC Rat CagesTara Martin2011 ULAR Summer Extern

IVC Cages

• IVC cages are meant to provide filtered air flow directly into each cage.

• They protect rodents from exposure to environmental contaminants and pathogens.

• Animals do not have direct access to room air, so ventilation is important to prevent build-up of CO2 and ammonia.

Tecniplast Cages•ULAR uses Tecniplast cages to house rats.

•These cages have an inlet l f l i d valve for clean air and an

outlet valve for contaminated air.

•To reach the cage, valves must push through self-sealing ports in the back of each cage lid.

Intact Valves

•

•Rat cages were found with condensation along the walls and lids.

• Some cages had broken or chewed

Damaged and Occluded Valves

broken or chewed valves.

• Other racks were found to have air valves clogged with debris.

Damaged Valves

Damaged valves cannot push the self-sealing cage ports open, compromising airflow.

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Occluded Valves

• The manual for these racks provided by Tecniplast has no recommendation for removing air valves when sanitizing or cleaning the rack.

• ULAR SOPs previously required racks to be sanitized every 6 months without removing valves. This SOP has been revised.

Current ULAR SOP• Valves are removed from the

rack and soaked in a bucket of 10% bleach solution for 10 minutesminutes.

• Valves are rinsed, placed in a wire basket, and run through a rack or tunnel washer.

• Nozzles are checked after washing to be sure they are clean. ▫ If not clean, valves are soaked

again and re-washed.

Our Project - Purpose• To see whether occlusion of valves affects the

build-up of ammonia in Tecniplast Sealsafe IVC cages.cages.

• To see how other institutions using Tecniplast Sealsafe caging systems clean their racks.

Hypothesis

• Cages with occluded air valves will have a faster increase in ammonia levels versus cages with valves that are not occludedvalves that are not occluded.

• Cages with occluded air valves will reach higher overall ammonia levels than cages with valves that are not occluded.

Materials and Methods• 16 rats were housed individually in Tecniplast

cages in four groups:▫ Fully Open Valves: Both inlet and outlet valves

were open and non-occluded.F ll O l d d V l B th l ▫ Fully Occluded Valves: Both valves were artificially occluded. This was done by removing both the inlet and outlet valves from the rack.

▫ Outlet Only: The fresh air inlet valve was artificially occluded by removing it from the rack.

▫ Inlet only: The outlet valve was artificially occluded by removing it from the rack.

Materials and Methods

• Ammonia was measured every day using pHydrion strips held 1 – 2” above bedding level.

• This was done for 14 days or until ammonia levels reached above 25 ppm.

• Two trials were performed – rats were shifted between groups to keep weights approximately equal across all groups.

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Results

11

14

Average Days In Study

100% Occluded 100% Open Outlet Only Inlet Only0

3

6

8

Day

s

*

Results

6

8

s

Cages Left Per Group Per Day

100% Occluded 100% Open 50% OccludedOutlet Only

50% OccludedInlet Only

1 2 3 4 5 6 7 8 9 10 11 12 13 14Day

0

2

4

Num

ber o

f Cag

es

Results

50

Average Ammonia Per Day

100% Occluded 100% Open 50% OccludedOutlet Only

50% OccludedInlet Only

1 2 3 4 5 6 7 8 9 10 11 12 13 14Day

0

25

Amm

onia

(ppm

)

Conclusions• Cages with fully occluded valves reached harmful

ammonia levels much more quickly than cages where inlet, outlet, or inlet and outlet valves are open.

• Air inlet and outlet valves should be routinely removed from the rack and checked to be sure they are not damaged or occluded with debris damaged or occluded with debris. • Unnoticed occlusion could lead to a rapid build-up in

ammonia to harmful levels.

• Air inlet and outlet valves should be cleaned routinely to be certain that air flows through cages appropriately.

• Tecniplast cages should not be used without cage wires to prevent damage to air inlet and outlet valves.

Survey• A survey has been sent out to other facilities

using Tecniplast cages.• Questions include…▫ Cleaning protocols for Tecniplast racks

T f b ddi d f d d i h f ilit▫ Type of bedding and food used in each facility▫ Number of rats housed in Tecniplast IVC cages at

each facility• Goal is to find out whether other facilities have

had similar issues with caging and to see what their cleaning protocols are like.

Rat Rack Cultures

Staph/ Strep sp.

Pre-rack /valve washing culture swab

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Rat Rack Cultures

Post-rack /valve washing culture swab No Growth!!

Extern: Ellen Scherer, Cass Summer Fellowship

• Currently a student of The Ohio State University, College of Veterinary Medicine to graduate in

2014 • Involved with clubs such as: SCAVMA, Radiology Club, ASLAP, OVMA and Omega Tau Sigma. Mentor: Dr Stephanie Lewis, DVM, MS, DACLAM. Director, Large Animal Clinical Medicine, University Laboratory Animal Resources; Assistant Professor, Clinical. Veterinary Preventative Medicine

Dr Lewis is Attending Veterinarian for OSU facilities and as the Director of Large Animal Clinical Medicine provides clinical and didactic support for the Laboratory Animal Residency Program. She is a member of ASLAP, ACLAD and AALAS, serves on the IACUC at OSU and at the Veterinary Institute at Bradford.

Research Project: Evaluation of Various Routes of Administration of Meloxicam for Postoperative Analgesia in Mice.

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Hi h t i bi di ffi it

Evaluation of Various Routes of Administration of Meloxicam for Postoperative Analgesia in Mice

Ellen Scherer Summer 2011

Non-Steroidal Anti-Inflammatory Drugs ¾ Commonly Used For:

¾ Fever ¾ Arthritis ¾ Analgesia

¾Mild to moderate

¾ Other uses: ¾ Endotoxemia ¾ Anticoagulant activity ¾ PDA closure

NSAID - pharmicokinetics

¾ Metabolized in the Liver

¾ Excreted by kidneys and in feces ¾ High protein binding affinity

¾ Liver metabolism is is limited by enzyme capacity, not blood flow

¾ Dosing varies by species

¾ High potential for drug interactions

NSAID - Goal… ¾ Inhibit the enzyme cyclooxygenase

NSAID - side effects

¾ GI Ulceration ¾ Impaired platelet aggregation ¾ Delayed parturition ¾ Blood dyscrasias ¾ Impaired bone healing ¾ Nephrotoxicity (horses)

NSAID - Side Effect Cont. ¾ Allergies ¾ Reproductive system

¾ Male fertility?

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Carries out normal physiologic production

COX 1 & 2

¾ The COX enzyme catalyzes arachidonic acid to form prostaglandins and leukotrienes

¾ Activation site is at the end of a long narrow hydrophobic “tunnel or channel”

¾ Heme-dependent peroxidase activity is required for COX activity

¾ COX 1 & 2 have different activation switches

COX 1 ¾ Constitutive Production

¾ Concentration with in the body remains stable

¾ Carries out normal physiologic production of prostaglandins

¾ Attachment site is smaller compared to COX 2 attachment site

COX 2

¾ Induced ¾ Not normally present

¾ Responsible for production of prostaglandins in inflammatory responses

COX in the Inflammatory Process

Inflammatory Stimuli (disease/trauma) -->

Membrane phospholipids release

Arachidonic Acid --> Cyclooxygenase catalyzes arachidonic acid

to prostaglandins & leukotrienes -->

Prostaglandins create inflammatory response

Cyclooxygenase catalyzes arachidonic acid to prostaglandins & leukotrienes

QuickTime™ and a TIFF (Uncompressed) decompressor

are needed to see this picture.

Aspirin Specifically ™ Aspirin is the only NSAID that covalently

modifies a residue in the “tunnel” of the COX compound. Thus, aspirin irreversibly inactivates both COX 1 & 2.

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Tylenol - Acetaminophen

¾ Synthetic ¾ Produces analgesia & antipyresis ¾ Does NOT possess significant anti-

inflammatory activity ¾ ~ 25% protein bound ¾ Contraindicated in cats ¾ Excreted in milk

Tylenol - Drug Interactions ¾ Can potentiate the effects of coumarin

or inandione anticoagulants ¾ Doxorubicin

¾ This leads to hepatotoxicity

Ibuprofen

¾ Anti-inflammatory, analgesic, & anti-

pyretic activities ¾ Proprionic acid derivative ¾ Non-specific COX inhibitor ¾ ~90% bioavailability in oral dosing of dogs ¾ Highly plasma protein bound ¾ Eliminated in feces and urine

Ibuprofen - Side Effects & Drug Interactions ¾ GI ulceration ¾ Blood thinning ¾ At high doses can cause renal effects ¾ Decrease in efficacy of blood pressure

lowering drugs ¾ Interferes with the secretion of lithium &

aminoglycosides

Ibuprofen - Dosing

¾ Rabbits: ¾ 2.2 mg/kg PO

¾ Rats: ¾ 5 mg/kg SC or 5-10 mg/kg PO

¾ Chinchillas: ¾ 4 mg/kg SC

Meloxicam ¾ “New” NSAID ¾ Selective inhibition of COX 2 ¾ Analgesic, anti-inflammatory, antipyretic ¾ ~ 97% protein bound ¾ Metabolites are excreted in the feces

¾ Significant enterohepatic recirculation

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Meloxicam - Half-life

¾ Species specific:

¾ Dogs = 24 hrs

¾ Pigs = 4 hrs

¾ Horses = 3 hrs

¾ Cattle = 13 hrs

Meloxicam - Drug Interactions ¾ Drug interactions occur by displacing other

drugs, or by being displaced by other drugs with high protein binding affinity ¾ If used with other drugs that alter hemostasis

and/or cause GI erosion there is an increased likelihood of bleeding or ulceration

¾ May antagonize the antihypertensive effects of ACE inhibitors

Medicine in the Water Bottles: Pros

¾ Minimal animal restraint and distress ¾ Less opportunity for administration

complications ¾ Antibiotics are available for administration

in the drinking water for poultry and livestock and their effectiveness and stability has been evaluated

Medicine in the Water Bottles: Cons ¾ Compounding the drug influences:

¾ Water type ¾ Dilution used

¾ May compromise chemical stability, purity, &

potency of active ingredient ¾ Other Factors:

¾ Water temperature ¾ pH ¾ Chemcial properties Reactivity ¾ Light

Journal: JAASLAS 39 (6)

¾ An evaluation of Analgesic Regimens for

Abdominal Surgery in Mice

Journal: JAASLAS 46 (5), 26-32 ¾ Amoxicillin - Clavulanic Acid and

Trimethoprim-Sulfamethoxazole In ¾ In this study mice were given

acetaminophen, acetaminophen- Rodent Feed and Water: Effects of

buprenorphine combo, or ibuprofen in the water bottle 1 day prior to surgery and continued there after.

¾ First 2 days post-surgery water consumption fell

Compounding on Antibiotic Stability ¾ Amoxicillin & clavulanic acid concentrations in water

bottles at extended times post mixing

¾ Used different types of water

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JAASLAS 46 (5), 26-32 - Cont.

¾ Expected, Initial Concentrations

¾ Amoxicillin --> 0.96 mg/ml

¾ Clavulanic Acid --> 0.14 mg/ml

JAASLAS 46 (5), 26-32 - Cont ¾ Actual Concentrations: Over 7 day period

¾ Amoxicillin ¾RO water --> 1.18 - 1.29 mg/ml ¾Tap water --> 1.09 - 1.22 mg/ml ¾Acid water --> 0.43 - 0.50 mg/ml

¾ Clavulanic Acid ¾RO water - statistically significant time-dependent

decrease in concentration beginning at 72 hrs ¾Tap water --> 0.02 - 0.04 mg/ml ¾Acid water - none detectable at any time point

Journal: JAASLAS 45 (6), 13-16

¾ Lack of Analgesic Efficacy in Female Rats

of the Commonly Recommended Oral Dose of Buprenorphine ¾ “An oral dose approximately 10 times higher

than that recommended was necessary to induce a level of analgesia similar to that of the therapeutic gold standard.”

Journal: JAALAS 45 (5), 48-54 ¾ Acetaminophen Self-Administered in the

Drinking Water Increases the Pain Threshold of Rats (Rattus norvegicus) ¾ Pros

¾Reduces stress on animals ¾Less staff time

¾ Cons ¾Neophobia

JAALAS 45 (5), 48-54 - Cont.

¾ Used 32 mg/ml cherry flavored

acetaminophen in water ¾ Findings:

¾ Initial neophobia to acetaminophen water & rats did not drink was much of it as tap water

¾ Rats that did undergo surgery did drink more acetaminophen water than unmanipulated animals

Evaluation of Various Routes of Administration of Meloxicam for Postoperative Analgesia in Mice ¾ The proposed project investigates the use of the non-

steriodal anti-inflammatory (NSAID) agent meloxicam as a suitable single agent for postoperative analgesia in mice.

¾ Evaluate the administration of the injectable formulation of Meloxicam via subcutaneous (SC) injection or in the drinking water, or the oral suspension in drinking water following laparatomy surgery in C57Bl6 mice.

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F d d W t it i

Evaluation of Various Routes of Administration of Meloxicam for Postoperative Analgesia in Mice

¾ Protocol Activities

¾ Survival laprotomy surgery

¾ Food and Water monitoring

¾ Behavioral Testing ¾Hot Plate Test

Resources „ http://cpharm.vetmed.vt.edu/vm8784/NSAIDS/nsaids.htm „ http://cti.itc.verginia.edu/~cmg/Demo/pdb/cycox/cycox.html „ Plumb’s Veterinary Drug Handbook, 5th Ed. „ An Evaluation of Analgesic Regimens for Abdominal Surgery in Mice „ http://cat.middlebury.edu/~chem/chemistry/class/bio/ch314/presentations/a

mrita/ „ Acetaminophen Self-Administered in the Drinking Water Increases the

Pain Threshold of Rats (Rattus norvegicus) „ Lack of Analgesic Efficacy in Female Rats of the Commonly

Recommended Oral Dose of Burprenorphine „ An Evaluation of the Analgesic Regimens for Abdominal Surgery in Mice „ Amoxicillin - Clavulanic Acid and Trimethoprim-Sulfamethoxazole In

Rodent Feed and Water: Effects of Compounding on Antibiotic Stability „ Judy Hickman-Davis, DVM, PhD, DACLAM