Kaye, GI and others Efficacy of Alkaline Hydrolysis as an Alternative
Method for Treatment and Disposal of Infectious Animal Waste. Contemporary
Topics 37 (3): 43.
Alkaline hydrolysis with hot (110 - 120 C) 50% NaOH solution under
12-15 lb/sq in pressure for 16-18 hours was sufficient to destroy samples
of pure cultures of selected infectious microorganisms during digestion
of 114 to 136-kg loads of animal carcasses in an animal tissue digestor.
The product resulting from digestion was a sterile, neutral (by EPA standards),
aqueous solution containing breakdown products of proteins, sugars, nucleic
acids, and fats of the animal tissue. The NAOH was consumed in the
process, primarily in the hydrolysis of the amide bonds of proteins and
other molecules and hydrolysis of ester bonds of fats (soponification),
producing a solution consisting largely of sodium salts of amino acids
and sodium salts of fatty acids (soaps). The New York State Department
of Health has approved the WR2 Model 100 Series Tissue Digestor as an alternative
treatment method for regulated medical waste. The authors have now
documented through this study the the WR2TM Process and the WR2TM Animal
Tissue Digestor are able to be used to digest and dispose of all biological
waste.
Questions:
1. What does the acronym ATCC stand for?
2. How do EPA standards define neutral solutions?
3. Will alkaline hydrolysis destroy prions?
4. T or F: The alkaline hydrolysis process works equally
well with fresh, frozen, or formalin-fixed or embalmed tissues?
Answers:
1. American Tissue Culture Collection (located in Rockville,
Md)
2. EPA standards define neutral products as those with a pH between
2.0 and 12.5 that can be released into the local sanitary sewer, subject
only to regulations that may be imposed by local sewer districts.
3. The alkaline hydrolysis method should destroy prions as one
of the standard procedures for treatment of materials contamined with prions
is soaking in 1N NaOH solution for 1 hour at ambient temperature.
4. True. Amino groups produced by the hydrolysis of proteins
initially form Schiff-base intermediates with formaldehyde and gluteraldehyde,
which then rearrange to form stable compounds, thus destroying the reactivity
of these characteristic hazardous wastes and producing biodegradable adducts.
Talyor, WJ and others The Effect of Duration of Individual Housing
on Social Behavior of Adult Male Bonnett Macaques (Macaca radiata). Contemporary
Topics 37 (3): 47.
Macaques are naturally gregarious and establish social relationships
with conspecifics. Lack of social contact for primates has been related
to abnormal or self-injurious behavior. The Animal Welfare Act and
the Guide for the Care and Use of Laboratory Animals have responded to
the need for provision of social contact by recommending that, whenever
possible, attempts be made to provide social housing for social primates.
Research settings often require single housing for periods of time for
a variety of reasons: administration of drugs, containment of infectious
diseases, restriction of movement, or assurance of food intake. Some
of these cases do not result in life-long single housing, and opportunities
may exist for the re-establishment of social interaction.
Several studies have revealed that macaques
that have been housed alone for varying periods can be successfully resocialized;
there have been few direct comparisons in the success rates for primates
that have been housed singly for long periods of time versus those housed
single for short periods of time. The study reported in this manuscript
was conducted to determine whether adult male bonnet macaques housed alone
would choose to interact with other similarly housed macaques when provided
with a group situation, whether there would be differences in the amount
and type of interaction between males with differing duration of single
housing, and whether these social interactions would change with time.
The study used 2 groups of 3 male bonnet macaques
who had been reared in stable family groups and had previously belonged
to the same social group. None had their canine teeth removed.
1 group had been singly housed for 24 months (long-term; LT) prior to the
study; the others had been singly housed for 1 month (short-term; ST).
The animals were kept in single housing and moved in transport cages once
weekly for 8 weeks to a social pen. The monkeys were fed prior
to movement. They were allowed to interact in the pen for 4 hours
and were unobtrusively observed through a one-way mirror. The
pen contained shredded paper bedding, food and seeds strewn among the bedding,
toys, and a number of shelves and perches.
The results indicated that, although all males
did seek social proximity with others, the LT group spent significantly
more time alone than the ST group, and this did not change over the course
fo the 8 week study. The ST group spend less time alone, and spent
progressively less time alone over the course of the study. The LT
group members spent almost none of the time grooming each other, whereas
St members spent significantly more time grooming. Although the primary
reason these males had been removed from group housing initially was fear
of aggression, there were few threats or incidents of contact aggression
for either group, and observer intervention was never required to prevent
escalating aggression. These results may indicate that ST males were
able to resume their previously established social relationships more quickly
than males in the LT group. Also, males in this study were able to
move and explore in the pen as well as make social contact, which may have
reduced the tendency toward aggression. The last factor was that
the temporary nature of the social experience ( only once per week, short
period of time, all animals fed prior to interaction) may have reduced
the need to test the social ranking within the group. Intermittent
social housing may be an option for singly housed macaques under appropriate
conditions.
Questions:
1) What is the AWA and Guide recommendation for primate housing?
2) What is the Order, Family, G&S for the bonnet macaque?
Answers:
1) Guide: "When it is appropriate and compatible with the protocol,
social animals should be housed in physical contact with conspecifics.
For example, grouping of social primates or canids is often beneficial
to them if groups comprise compatible individuals."
AWA: "(a) Social grouping. The environment enhancement
plan must include specific provisions to address the social needs of nonhuman
primates of species known to exist in social groups in nature."
2) Order: Primate, Suborder: Anthropoidea, Infraorder: Catarrhini,
Family: Cercopithecidae, Macaca radiata
Goodwin, SD Comparison of Body Temperatures of Goats, Horses, and
Sheep Measured witha Tympanic Infrared Thermometer, an Implantable Microchip
Transponder, and a Rectal Thermometer. Contemporary Topics 37 (3): 51.
Body temperature of goats, horses, and sheep was measured using
3 methods: tympanic temp with tympanic infrared thermometer, subcutaneous
temp via implantable microchip transponder, and rectal temp via digital
thermomemter. Core body temp is considered the temp of the hypothalamus
or deep body sites and is the criterion-referenced standard; but measurement
of core body temp can be difficult to assess without using invasive techniques,
such as pulmonary artery catheterization, distal esophageal probe, urinary
bladder catheterization or placement of a probe in direct contact with
the tympanic membrane. Less invasive methods to obtain body temp
in man includes oral, axillary, or rectal thermometry; in vet med it has
almost exclusively been limited to rectal thermometry. Technological
advances have made available other methods of measuring temp: tympanic
infrared thermometry and implantable transponder, but no databases
exist for these values.
Authors conducted this study on 35 sheep,
30 goats, and 18 horses group-housed on pasture. Temperatures were
measured 3 times by each method for 9 measurements total for each animal.
Mean and SD of temperatures and coefficients of variation for each method
were determined. For all species, temperatures by SQ microchip were
most variable and temps measured rectally by digital thermometer were least
variable. Tympanic and SQ transponders were easy and convenient to
use, except in horses. Horses objected to insertion of the tympanic
probe into their ears. Both methods produced a reading within seconds,
compared to minutes required by rectal thermometry. Tympanic infrared
thermometry correlated well with traditional rectal thermometry in goats
and sheep and should be considered as a viable alternative in those species.
Implantable microchip transponders in goats correlated well with rectal
temps, and could be used in this species. Due to the poor correlation
with rectal thermometry and reaction of some animals to insertion of the
tympanic probe, neither of the alternative methods appear to be useful
in horses at this time.
Advantages of tympanic and subcutaneous transponder
thermometry over rectal thermometry: require much less time to get a reading,
decrease risk of transmission of disease between animals, reduce need for
physical restraint, and microchips offer advantage of being able to program
animal ID code into chip as well. Disadvantages: microchip
is expensive, tympanic thermometry result prone to variation depending
on operator technique, both lack an extensive database of reference range
values compared to rectal thermometry.
No questions.
Chronic Collection of Mesenteric Lymph From Conscious, Tethered Rats.
Contemporary Topics 37 (3): 56.
The authors developed a rat model to allow collection of mesenteric
lymph for up to 5 days from conscious, minimally restrained rats.
The model obviates the need for total restraint or general anesthesia,
both of which are known to influence intestinal lymphatic transport of
test compounds in unpredictable ways. Intestinal lymph flow rate
during the first 24 hours after surgery averaged 2.23+/- 1.01 mL/hr, increasing
to 4.89 +/- 1.64 mL/hr thereafter which is greater than that previously
described for methods requiring anesthesia or restraint of the animals.
The authors propose this model to assess the effects of formulation on
the lymphatic transport of xenobiotics.
Instruments/devices used in the procedure and mentioned in the article
include: Alm retractor, Sterling probe, Vannas microsurgical scissors,
cellulose patch and Vetbond Tissue Adhesive No. 1469, 9mm stainless steel
wound clips, rodent jacket with stainless steel tether, and metabolic cage.
Questions:
1. The collection of mesenteric lumph is important in what types
of studies?
2. What are some of the potential advantages of lymphatic transport
of orally administered drugs?
Answers:
1. Studies involving the transport of lipids and lipophilic xenobiotics,
various aspects of immune functioning, and the etiology of cancer cell
metastasis and HIV infection.
2. Avoidance of hepatic first-pass metabolism; localized treatment
of mesenteric lymphatic diseases; targeted therapy of cancer cell metastases
and diseases of certain portions of the lymphatic system; and transport
of drugs by the lymphatic system may promote the incorporation of the agent
into the body's lipid-handling system (potential to manipulate drug distribution
and residence time within the body).
Levine, S and Saltzman, A An Alternative to Overnight Withholding
of Food from Rats. Contemporary Topics 37 (3): 59.
Research protocols for rats frequently include withholding of food
overnight for several reasons, one of which is to reduce the size of the
stomach and cecum to reduce chances of accidental penetrations that may
occur during intraperitoneal injections. Side effects of this practice
are a loss of body and hepatic weight and decreases in blood glucose concentrations,
and ingestion of bedding material for those animals housed on contact bedding.
The authors proposed the use of sucrose cubes as a food source overnight
and reducing access to bedding as an effective alternative to overnight
fasting. Sucrose-fed rats lost less body weight, lost little or no
hepatic weight, and did not have hypoglycemia, compared with rats from
which food was withheld overnight. Low serum urea nitrogen concentration
detected for sucrose-fed rats was probably related to a decrease of protein
catabolism for gluconeogenesis and was not considered a pathologic change.
Questions:
1. Feeding sucrose cubes overnight to rats prevented their ingestion
of bedding material?
2. In this study, withholding of food overnight from rats reduced
hepatic weights by up to what percentage of normally-fed controls?
Answers:
1. When fasted rats had access to bedding, they ate it.
Similarly, rats fed sucrose also ate bedding, but apparently ate less bedding
than rats from which food was withheld (visual inspection of cecal contents
only).
2. Overnight withholding of food was sufficient to cause a striking
reduction (as much as 25%) in hepatic weight.
Storrow, AB and Hoxie, N Modification of Subdural Catheters for Long-Term
Intracranial Pressure Monitoring of Conscious Rabbits. Contemporary Topics
37 (3): 62.
This paper describes a method for chronic intracranial pressure monitoring
in conscious rabbits. Intracranial pressure monitoring has been successfully
done in the past in rabbits that are anesthetized but has been mostly unsuccessful
in conscious rabbits. These investigators decided to use subdural pressure
monitoring (other choices are parenchymal, ventricular, epidural). Surgery
entailed drilling a hole in the skull and placing a Codman MicroSensor
ICP Transducer (Johnson and Johnson Professional) between the dura and
the cerebrum. The catheter was tunneled caudally through the subcutaneous
tissue to exit between the scapulae. The catheter was protected by encasing
it in a silicon tube and the proximal end that inserts into the control
unit was protected by encasing it in fiberglass splinting material.
This technique enabled 9 of 12 catheters to remain patent for the duration
of the study.
Question:
The rabbits used in this study were specific-pathogen free New Zealand
White (Myrtle's Rabbitry). What pathogens are these rabbits free from?
Answer:
Bacteria: Pasteurella multocida,
P. pneumotropica, Bordetella bronchiseptica, Treponema cuniculi, Clostridium
piliformis, Carbacillus spp., and Salmonella spp.
protozoans: Encephalitozoon
cuniculi, Eimeria spp., Eimeria stiedae, and Toxoplasma gondii
helminth: Passalurus ambiguus
and Taenia pisiformis
arthropod: Psoroptes cuniculi,
Cheyletiella parasitovorax, and Listrophorous gibbus
virus: oral papilloma virus
Smith, SM and others Novel Techniques for Testing of Esophageal Irritancy
of Liquids and Tablets in Dogs. Contemporary Topics 37 (3): 66.
This paper describes a method for administers oral compounds to the
proximal one-third of the esophagus in anesthetized beagles. For liquid
compounds, a 5 mm endotracheal tube was placed in the esophagus and the
balloon cuff inflated. Then a 8 French rubber catheter was passed through
the tube and extended 1 inch past the end of the ET tube. While the cranial
portion of the dog was elevated, an infusion pump was used to administer
the compound over 30 min. For tablet forms, a 10 inch piece of vinyl tubing
was placed in the esophagus. A tablet tied to a suture that was 1 inch
longer then the tube was placed via endoscopic retrieval forceps for 1
hr. After the study the dogs were euthanized and observed for gross and
histopathologic changes to the esophagus. The paper also describes the
techniques that the investigators used to ensure reproducibility.
No questions
Hammond, PD, Stutzenberger, F, and Butler, RN Use of a Disposable
Suringe as a Novel Economic Breath-Collection Chamber for Mice. Contemporary
Topics 37 (3): 70.
This article discusses a novel method to be used as an alternative
for conventional breath-collection chambers. In this particular study
the 13-C-urea breathe test was used. The chamber was a modified 50cc
syringe with 4 holes drilled into the flange end (for ventilation). These
holes could be closed with the plunger at the time of sample collection.
A three-way stopcock valve and a 21 gauge needle were used on the syringe
tip. A size comparison was made between the Terumo (i.d. = 28.8 mm)
and the Becton Dickinson (i.d. = 25.5 mm) 50cc syringes for ability of
mice to re-orient themselves in the chamber. Little difference was
found between the two, however, the smaller diameter discouraged attempts
to turn around. Mice were maintained in these chambers for no more
than 20 minutes, however, the average time for taking several breath samples
usually required no more than approximately 8 minutes in chamber.
The chamber appeared to cause little or no distress for the mice, and the
concentration of samples collected, based on volume, were more than adequate.
QUESTIONS:
1. What 2 test methods are currently being used in the diagnosis
of
Helicobacter species infection ?
2. What is now the concern with treatment/cure of H. pylori infection
?
ANSWERS:
1. The CLO test (method to detect urease production by the H.
pylori) and
breath testing.
2. Increased incidence of esophageal reflux. (Veterinary
Medicine/December 1997)