Laboratory animals encompass various vertebrate species, including common laboratory animals, quadrupeds, wildlife, and aquatic species, which are bred and utilized for research, testing, and educational purposes. It is imperative that all animals involved in these activities are provided with the highest standard of care and humane conditions. The Guide for the Care and Use of Laboratory Animals serves as a strong advocate for the welfare of animals and emphasizes that individuals involved in their care, utilization, or production for research, testing, or teaching must assume responsibility for their well-being. This guide, authored by scientists and veterinarians for their professional peers and the wider community, aims to uphold the scientific rigor and integrity of biomedical research involving laboratory animals. Scientists and researchers are ethically obligated to consider alternative animal methods and ethical concerns while pursuing new scientific advancements and knowledge that involve the use of these animals. The three R's (Replacement, Reduction, and Refinement) should be integral to the decision-making process:

• Nude Mice

Type:

• Immunodeficient, Inbred Nude Mice: NU/J

Coat color:

• Homozygous: Hairless and pigmentless
• Heterozygous: Hairy and albino

Gestation period: 21 days

Recommended Storage Temperature: 26-28 degrees Celsius

Due to their immunodeficiency, nude mice have proven to be valuable assets in various fields of biomedical research, including drug discovery, xenotransplantation, and cancer research. These mice carry a deletion in the FOXN1 gene, resulting in the absence of the thymus gland and impaired T-cell maturation. As a consequence, nude mice may exhibit sparse and structurally deficient fur or whiskers that are prone to breakage during growth. Furthermore, they do not produce mature T-cells and typically have lower levels of circulating lymphocytes compared to normal or heterozygous mice. This immune deficiency also leads to a lack of antibody production, allowing foreign cells or tissues to grow and integrate into the host mouse.

Collectively, these characteristics render nude mice an excellent model for transplanting tumor cells, understanding the mechanisms underlying tumor malignancy, and evaluating the efficacy of potential therapies. Inbred strains are created through at least 20 generations of sibling or parent-offspring matings, resulting in a genetically homogeneous background. This genetic consistency enables reliable and reproducible growth of allogeneic cell lines. Nude mice are typically housed in specific pathogen-free (SPF) environments. This involves subjecting food, bedding, water containers, and cages to autoclaving and sterilization processes. Additionally, the mice are provided with acidified water. Access to the mice is restricted to authorized personnel who follow strict protocols, including wearing protective footwear, clothing, gloves, hair coverings, and cleanroom masks. Regular screening for pathogenic organisms is also conducted. The cages housing the mice are autoclaved and maintained in racks equipped with HEPA-filtered laminar airflow systems. All research studies involving nude mice are conducted within laminar hoods equipped with HEPA filters, ensuring positive pressure and optimal conditions for the specific research being performed.

• BALB/C Mice

Type:

• Mus musculus

Coat color:

• Albino, white

Origin:

• From the same bloodline

Age of sexual maturity:

• 6 weeks

Gestation period:

• 20 days

Optimal reproductive age span:

• 7-8 months

Breastfeeding period:

• 3 weeks, until the weight reaches 10 grams

Ideal storage temperature:

• 20-24°C (litters: 30-32°C)

Ideal humidity:

• 45-65%

Lifespan:

• Up to 36 months old

Nocturnal animals

Hearing range: 1 kHz - 100 kHz

Highly social animals

Suitable for:

- Creating animal models of cancer tumors

- Production of monoclonal antibodies

- Cardiovascular research

- Testing different chemotherapy drugs and vaccines

• C57BL/6 Mice

Type:

• Mus musculus

Coat color:

• Black

Origin:

• From the same bloodline

Age of sexual maturity:

• 6 weeks

Gestation period:

• 20 days

Optimal reproductive age span:

• 7-8 months

Breastfeeding period:

• 3 weeks, until the weight reaches 10 grams

Ideal storage temperature:

• 20-24°C (litters: 30-32°C)

Ideal humidity:

• 45-65%

Lifespan:

• 27-29 months

Nocturnal animals

High sensitivity to smell and sound, as well as to pain and cold stimuli

Limited response to painkillers

The second mammal to have its whole genome sequenced, following humans

Suitable for creating models of diabetes and obesity

Useful for genetic studies

Suitable for developing Alzheimer's disease models, models of multiple sclerosis (MS)

An animal model for epilepsy

Suitable for studying blood pressure

• NMRI Mice

Type:

• Mus musculus

Origin:

• Outbred

Coat color:

• White, albino

Shorter lifespan

Easy to handle and manage in laboratory settings

Suitable for toxicity studies, teratology research, ascites models, pharmacological studies, and physiological investigations

• Wistar Rat

Type:

• Rattus Norvegicus Domestica

Coat color:

• White, albino

Origin:

• Outbred

Age of sexual maturity:

• 10-20 weeks

Gestation period:

• 20-22 days

Optimal reproductive age span:

• 9-10 months

Ideal storage temperature:

• 20-24°C

Ideal humidity:

• 45-65%

Lifespan:

• 27-29 months

Nocturnal animals

Poor vision

Playful animals

Suitable for ophthalmology studies, nutrition research, metabolism studies, cancer research, toxicology studies, creating models of diabetes and metabolic syndrome, studying acute lymphocytic leukemia, stroke research, and investigating Alzheimer's disease

• New Zealand White Rabbit

Type:

• Oryctolagus Cuniculus

Coat color:

• White, albino

Origin:

• Outbred

Age of sexual maturity:

• 10-20 weeks (Ideal gestation period: 5-8 months)

Gestation period:

• 28-35 days

Optimal reproductive age span:

• 9-10 months

Ideal storage temperature:

• 17-21°C

Ideal humidity:

• 30-70 %

Lifespan:

• 5-7 years

Playful Animals

Easy to handle

Social

Suitable for toxicity studies, assessing drug sensitivity, antibody production, conducting ophthalmic sensitivity and inflammation tests, nutrition research, metabolism studies, and investigating tissue engineering in hard tissues such as bone, joints, and skull

Avicenna Research Institute (ARI), Chamran Expressway, Evin, Tehran, Iran

Tell: +98 (21) 22432020- Ext. 423, +98 (21) 22432020- Ext. 315, +98 (21) 22432020- Ext. 225

Email:

Working schedule:

The center operates from Saturday to Wednesday, between 8:00 AM and 4:00 PM