What are the SPF animal feeding management requirements and conditions?
SPF动物
z-bo
2022-02-02
678
(1) Basic concepts
Except for pathogens that need to be excluded from clean animals, there are no major potential infectious diseases or pathogens that cause conditional diseases and interfere with scientific experiments. Such animals are called certain pathogen-free (SPF) animals. SPF animals are derived from sterile animals and must be kept in the barrier system under strict microbial control. SPF animals are suitable for all scientific research experiments and are now internationally recognized as international standard laboratory animals. The animals used to make various vaccines must be SPF animals.
(2) SPF laboratory animal care and management requirements and importance
In the process of animal testing, animals of the same species and different strains react differently to drugs, and different animals react differently to poisons. It is also very large. In addition, the influence of microbial interference and animal health quality on the experimental results cannot be ignored. If the animal is in poor health, it will not be possible to conduct experiments, especially for certain long-term experiments. For example, if there is no SPF feeding condition, the life of the animal cannot reach the cycle required for the experiment (carcinogenicity research, etc.). The above situation can be avoided because SPF animals have a clear genetic background and clear microbial status. SPF animals have many disciplines, including biomedical research (pharmacology, pathology, oncology, infectious diseases, etc.), vaccine manufacturing, biological identification, human tumor xenotransplantation, and preclinical pharmacology and toxicology of new drugs. can use. Nude mice are the most commonly used SPF animals in carcinogenicity experiments (such as research and carcinogenicity experiments). Nude mice are congenital hairless and athymic mutants of mice. It is a pure B-cell animal with no T-cell dependent immune response. Nude mice have congenital T-cell immunodeficiency, so they are used as recipients of xenogeneic or allogeneic tissue transplantation (especially human malignant tumor transplantation) to study carcinogenesis and immunological monitoring mechanisms and malignant tumor invasion. I can do it. Metastasis mechanism, screening of anti-cancer drugs and carcinogenicity of cultured cells in vitro. Nude mice are biochemical incubators for mass production of various animal cells.
(3) Breeding and management of SPF laboratory animals
1. The conditions of the breeding environment are as follows: the breeding environment temperature is 18-29°C, the daily temperature difference is below 3°C, the relative humidity is 40%-70%, the outside air changes 10 times/h, and the wind speed is ≤0.18m/s. , The pressure difference should be 25Pa, the cleanliness should be 10,000, the ammonia concentration should be 15mg/m3, the noise should be ≤60dB, and the illumination should be 150~300Lux.
2. The livestock area and auxiliary facilities of facility management SPF should be cleaned, dusted, cleaned and wiped several times before opening. Then smoke with formaldehyde + potassium permanganate for 24 to 48 hours, and then turn on the air supply and exhaust system for 24 to 48 hours to remove the residual pungent odor. The staff wore high-pressure disinfectant and dust-proof clothing in the breeding grounds. Clean up smoking equipment and wipe off spilled potassium permanganate with oxalic acid to improve hygiene. It can only be used after passing the technical supervision of the national animal supervision department and obtaining the facility certificate. The National Animal Seed Bank must strictly control and implement animal quality to ensure that the animal quality meets the standard requirements.
3. The flow of people/things/animals The flow of people is 1 dressing room→2 dressing rooms→air shower→clean corridor→care area→experimental area→second clean corridor→buffer room→exit barrier system. Specific operation: first wash hands with soap to elbow joints, take off all clothes and accessories in the dressing room, put on autoclaved cotton clothes, pants, masks and hats, use ethanol for 75% in the second dressing room Wash your hands, after about 10 minutes, dry your hands with a sterile dry towel. Soak a cotton ball with surgical disinfectant, then place your hand on your elbow. Put on medical gloves and anti-static clothing (hat, clothes, pants, socks), and then wrap the door lock with a towel dipped in alcohol to open the door. Air shower for about 20 seconds, and then enter the breeding and testing area through a clean corridor. Wear gauze gloves at the beginning of the operation (change gauze gloves when changing cages to feed animals). After the operation, enter the buffer room of the second clean corridor and exit the barrier system..
The flow of items: double-door autoclave (through windows, water) → clean storage room → clean corridor → buffer room → exit barrier system → disinfection room. Specific operation: autoclaved cages, drinking water, feed, bedding (animals, eggs, vitamins that cannot be autoclaved can be disinfected with ultraviolet rays or disinfectants through moving windows or faucets) cleaned from the opposite door into clean storage And use a clean trolley to push the sterilized items into the clean corridor leading to the breeding and testing area. The used bedding, water bottles, cages, etc. are sent to the secondary cleaning corridor in the secondary cleaning cart, and the barrier system is buffered and cleaned in the decontamination room.
Animal flow: outsourcing → quarantine room → breeding area → clean corridor → experimental area → secondary clean corridor → buffer room → exit barrier system. Specific operation: After the animal is weaned (28 days or one month ago), the staff will make a detailed reproduction record, indicate the date of birth, and reach the experimental area through a clean corridor. Before the experiment, the body type, sex, age and weight of the rat should be clarified, and the experimental methods and requirements should be clarified. After the experiment, the animal passed through the buffer room in the corridor and left the barrier system. Animals purchased outdoors should be observed in the isolation room for 7 to 14 days, and then enter the experimental area through a clean and tidy corridor.
Four. Daily management
(1) Garbage: The garbage in each autoclave can only be used after autoclaving. The cage is changed twice a week. Please dispose of your garbage in time to prevent environmental pollution.
(2) Acidic water: Pour purified water into the filter, add hydrochloric acid to adjust the pH to 2.8 to 3.0, add vitamin C and multivitamin B before use, replace it twice a week, and replace the stopper. Please check and pay attention. The water drowned the animal.
(3) Feed: Use sterile and nutrient-rich feed, feed it for 3-4 days at a time, add boiled eggs and sterilized sunflower seeds.
(4) Lighting: bright for 2 hours, dark for 2 hours.
(5) Reproduction: The ratio of males to females is 1:2-3, randomly allocated in the same cage, and non-pregnant females are replaced with males every two weeks. People who are not pregnant or whose mothers are of a weaker sex are excluded.
(6) Nude mouse pup exhaustion: Heterozygous mice are normal in all respects, because homozygous mice are hairless and lack normal thymus. Therefore, during the reproduction process, homozygous (nu/nu) can be used for experimentation and reproduction, and heterozygous (nu/+) female mice can be used for reproduction. In order to ensure the healthy growth of other puppies, (nu/nu) male mice usually have poor viability, and (nu/+) mice are especially prone to suck milk, so (nu/+) male mice are usually Eliminate it within the first week. It should be deleted as soon as possible.
(7) Card registration records: each animal, a card (breeding card, experimental card) and detailed animal species, strains, code (name), date of birth, retention date, mating date, spouse code need to be recorded, birth Date, number of litters, survival status and weaning date. Hang up the experimental record card of the experimental animal, and record the type, strain, sex, nature, group and quantity, method and results (drug dose, tumor size, etc.) of the experiment. All record cards must be correctly classified, stored and archived as a kind of raw data.
(8) Cage cleaning and requirements: first scrape the loose cage fragments with a bamboo scraper, and then pour it out. Soak in clean water, then scrub with a brush, and wash the inside and outside of the cage with detergent thinner; finally, rinse thoroughly with clean water to prevent residual detergent from irritating the animal's skin, pile up and dry, and wait for the autoclave. Follow the same steps to wash and wipe all the dirt covered for disinfection. Before each use, please clean and disinfect the used water bottles, straws, knives, etc. (the water bottle should be wiped with a bottle washing brush, and there is no dust, moss, etc.).
Fives. All management personnel must be related professionals such as medicine or zoology, and have undergone strict professional training. All aspects of aseptic operation and various equipment and facilities, storage methods and the use of animal husbandry technology will be fully and skilled. Love animals, don't bully or abuse animals. When entering the operation of the barrier system, control personnel must strictly control contamination and carefully perform aseptic operations. After the work is completed, wipe the walls and floor of the animal room with a wet towel in the alcohol room. Do not reverse the entrance and exit lines. The entrance and exit barrier systems must be opened with UV lamps. Air disinfection for 1 hour. The personnel using the autoclave must be professionally trained and qualified. The operating procedures of the autoclave must be mastered (gauge pressure 0.1 lMPa, temperature 121°C, constant temperature and 30 minutes constant pressure), and safe operating procedures must be strictly implemented. The entire disinfection process must be supervised by a dedicated person to prevent accidents. The administrator must constantly check the operation of various devices and equipment. The initial efficiency filter membrane in the new exhaust device of the engine room depends on the dust filtering conditions. Some filter membranes are replaced and cleaned once a week, and the barrier system performs standardized monitoring of microorganisms once a quarter. The care and management of SPF animals has improved the quality and level of scientific research by strictly controlling the microbial conditions in care, management and operation, which has led to more standardized environmental factors and longer-lived animals.
