Acclimation of Large Animals

Introduction

Boston University is committed to observe federal guidelines and AAALAC International guidelines for humane care and use of animals.

“Transportation unavoidably causes stress in animals. Although stress is not always an adverse experience and is a necessary and regular aspect of life, it causes changes in an animal’s physiological status during transportation and for some period thereafter. Utilizing transported animals before their physiological status normalizes can have considerable and unintended effects on research results”.(1)

Transportation refers to transportation from a vendor or from other institutions or campuses, including intracity, intercity, intrastate, interstate or international and involves truck and/or air transport. This policy does not address within campus transport.

Large animals acquired from approved vendors with defined health profiles may not require quarantine, but “newly received animals should be given a period for physiologic, psychologic and nutritional stabilization before their use. The length of time for stabilization will depend upon the type and duration of animal transportation, the species involved, and the intended use of the animals.”(2) This policy does not address quarantine. This policy does not address acclimation of nonhuman primates (NHP).

In order to prevent additional stress to newly arrived animals and prevent confounding of research data due to the experimental animal not having regained homeostasis after shipping, Boston University has established the following policies for acclimation of newly arrived USDA regulated large animal species.

Definitions

A. Shipping stress

Stress associated with being removed from a familiar background and surroundings and being exposed to numerous new experiences, including shipping crate, different food, noise and temperature variations and means of transportation.

B. Acclimation (= Acclimatization)

1. Becoming accustomed to new housing, food, water, handlers, cage mates, noises, smells, light cycle and other variables and regaining homeostasis.

2. Physiological adjustment of an organism to environmental change (Merriam-Webster’s Collegiate Dictionary, 11th ed.)

C. USDA regulated large animal species include rabbits, cats, swine and ferrets and may include other large animal species.

NHP require longer acclimation, quarantine and special procedures and are treated in a separate policy.

Policies for large animal acclimation after shipping

A. BU requires an acclimation period of seven (7) full days for large animals prior to any use for survival experiments.

B. Euthanasia and tissue harvest is allowed on day of arrival.

C. Nonsurvival surgery or other terminal nonsurvival procedures are allowed day after arrival. However, the PI is advised to consider the effect that shipping stress may have on the experimental data.

Procedures for care of USDA regulated large animal species during acclimation.

LASC/LACF staff is responsible for evaluating health status of large animals on arrival and during acclimation. LASC/LACF staff are responsible for documentation during the acclimation period. During this time PI and research staff are encouraged to familiarize themselves with their new animals.

A. Rabbits (6)

1. Rabbits are examined on arrival and ID, sex and weight are verified and noted in a prepared individual animal health record or in the animal room log sheet.

2. If space is available, newly arrived rabbits are housed in a separate animal room.

3. Newly arrived rabbits are placed on restricted feeding according to LASC/LACF SOP.

4. During the acclimation period animal appearance and behavior and food consumption, urine and feces are closely monitored and documented daily.

B. Ferrets (7)

1. Ferrets are examined on arrival and ID, sex and weight are verified and noted in a prepared individual animal health record or in the animal room log sheet.

2. If space is available, newly arrived ferrets are housed in a separate animal room.

3. Juvenile ferrets are routinely pair-housed.

4. During the acclimation period animal appearance and behavior and food consumption, urine and feces are closely monitored and documented daily.

C. Swine (8)

1. Swine are examined on arrival and ID, sex and weight are verified and findings noted in a prepared individual animal health record.

2. If space is available, newly arrived swine are housed in a separate animal room.

3. Swine of a different breed and/or health status are housed separately.

4. During the acclimation period animal appearance and behavior and food consumption, urine and feces are closely monitored and documented daily.

D. Cats

1. Cats are examined on arrival and checked for USDA ID number, sex and weight and findings noted in a prepared individual animal health record.

2. If space is available, newly arrived cats are housed in a separate animal room.

3. During the acclimation period animal appearance and behavior and food consumption, urine and feces are closely monitored and documented daily.

Background

A. Factors affected by shipping stress and acclimation

1. “Stress associated with transportation has widespread effects on physiological systems in laboratory animals, including changes in the cardiovascular, endocrine, immune, central nervous, and reproductive systems. Although short-lived, these changes can confound research if animals are utilized before homeostasis is restored and physiological measures return to normal. Therefore, some period of acclimatization following transportation is generally suggested to restore homeostasis. The following two questions should be considered to establish an adequate period for acclimatization:

(1) Will anticipated physiological changes confound the research to be conducted?

(2) What is the length of time necessary for confounding physiological changes to normalize?

Finding answers to those questions in the literature can be a challenge. Most literature on the physiological impact of transportation involves agricultural animals, although the limited literature in common laboratory animal species generally parallels changes documented in agricultural animals. The literature documents elevated heart rate and weight loss, as well as elevated concentrations of adrenaline, noradrenaline, glucose, cortisol, free fatty acids, and β-hydroxybutyrate. Carbohydrate, protein, and lipid metabolism (both lipolysis and lipogenesis) are altered, and plasma osmolality, albumen, protein, and pack-cell volume increase. Neutrophilia and lymphopenia are also evident. These measures generally return to baseline within 1 to 7 days of transportation, although animals that are young, severely stressed, and have stress-sensitive genotypes may show altered physiological measures for several weeks. Other measures such as circadian rhythm and reproductive performance may take several weeks to months to normalize”.(1)

2. “Numerous studies demonstrate the beneficial effects of frequently handling research animals before initiation of study protocols as well as in early life”.(6)

3. “Animals habituated to the handler or which are gentled in early life show less handling stress in later life and react only to the particular experimental stimuli used in the study, whereas nonhandled animals are much more likely to react to a new handler as well as to the test situation.”(6)

B. It is in the Principal Investigator’s best interest to ascertain how the studies undertaken are confounded by transportation stress.

For example: It has been reported that subsequent to transportation
• Immunologic functions are inhibited (3,5)
• Cortisol levels are elevated (3,4,5)
• Serum chemistry parameters are affected (4)

• Behavior is affected (5)

 

References

1. Jennifer A. Obernier and Ransom L. Baldwin, 2007. Establishing an Appropriate Period of Acclimatization Following Transportation of Laboratory Animals. ILAR Journal 47(4).
2. The Guide for the Care and Use of Laboratory Animals. NCR ILAR 1996, P.58.
3. McGlone, JJ et al Shipping stress and social status effects on pig performance, plasma cortisol, natural killer cell activity, and leukocyte numbers. J Anim Sci 1993 Apr 71(4):888-96.
4. Mahuren, JD et al Adrenocorticotropic hormone increases hydrolysis of B-6 vitamers in swine adrenal glands. J Nutr 1999 Oct 129(10):1905-8.
5. Hicks TA et al Behavioral, endocrine, immune, and performance measures for pigs exposed to acute stress. J Anim Sci 1998 Feb 76(2):474-83.
6. Conour, LA, Murray, KA and Brown, MJ 2006. Preparation of Animals for Research – Issues to Consider for Rodents and Rabbits. In Preparation of Animals for Use in the Laboratory. ILAR Journal 47(4):283-293.
7. Ball, Roberta Scipioni 2006. Issues to Consider for Preparing Ferrets as Research Subjects in the Laboratory. In Preparation of Animals for Use in the Laboratory. ILAR Journal 47(4):348-357.
8. Smith, AC and Swindle, M 2006. Preparation of Swine for the Laboratory. In Preparation of Animals for Use in the Laboratory. ILAR Journal 47(4):358-363.

BU IACUC Approved June 2009