Showing posts with label Laboratory Animals. Show all posts
Showing posts with label Laboratory Animals. Show all posts

Friday, March 16, 2018

CLEANING AND TAGGING OF LABORATORY ANIMALS



Cleaning
  • Change rabbit & rodent bedding. 
  • Change & sanitize cage weekly or up to twice weekly for rats and spot changed later in the week if needed. 
  • Change pans are sanitize twice weekly or biweekly. 
  • Sanitize all water bottles, stoppers, and sipper tubes weekly, replace bottles/replenish feed as needed. 
  • Sweep if necessary. 

Tagging (Identification)

Small rodents
  • Rodents must be identified to the cage level, by protocol number, investigator, species, strain, sex, contact name and number, date of arrival or birth and age. 
  • Rodents may be identified individually by tattooing, microchips, ear punches, ear tags, clipping hair, dyes, magic marker. 
Rabbit & guinea pigs
  • Guinea pigs, chinchillas and rabbits must be identified to the cage level similar to small rodents. 
  • Individual animals may be identified with tattoos, microchips, dyes, hair clipping or Magic Marker.

FEEDING OF LABORATORY ANIMALS - SMALL RODENTS (MICE,RATS AND HAMSTER)


Feeding of laboratory animals - Small rodents (Mice, rats, hamster)

  • Feed rodent chow.
  • Feed a high fat chow for breeding animals for extra energy, low fat diet for non breeding animals
  • Put food in the mouse food hoppers at least 1/2-2/3 full and fill completely weekly. 
  • Never recycle food.
  • Give mice and gerbils 3-6 grams of food per day- approximately one biscuit per animal per day; hamsters 15-20 g, or 3-4 biscuits/animal/day; rats 20-50 g or 4-10 biscuits/animal/day. 
  • Pellets provide something to gnaw on and help wear down the continuously growing incisor of rodents. Powdered diets usually require addition of a gnawing substrate or monitoring of tooth growth. 
  • Place food pellets on the bottom of the cage for hamsters with litters.
  • Some diets need to be sterilized. If this is done by autoclaving, it is essential to use an autoclaveable chow that is formulated to be nutritionally adequate after being exposed to high temperatures. Irradiated diets are already sterile and do not require autoclaving. 


Watering - Small rodents 
  • Re-fill bottle that are less than 1/2 full.
  • When filling, leave 1 to 1-1/2" of air space in the top of the bottle so it functions normally. 
  • Replace if the water bottles leaks.
  • An adult mouse or gerbil consumes less than 10 ml water per day; hamsters 25 ml/animal/day; rats 20-75 ml/animal/day. A water bottle holds 500 ml. 
  • Use potable water to fill bottles. 
  • Mice less than 6 weeks of age or 20 g, unweaned animals, and animals within the first two weeks of weaning must have a free-flow rather than a ball-bearing sipper tube in their cage water bottle, unless otherwise specified.
  • Sanitize water bottles and sipper tubes weekly. Soak sipper tubes in a in a detergent-disinfectant for an hour to remove debris. Check the function of the ball bearing in ball-bearing sipper tubes. If the bearing sticks, discard the tube. 

Feeding - Rabbits & guinea pig
  • Check food hoppers every day for caked or dusty feed. Discard caked feed and "fines" as necessary. 
  • Check feed labels as guinea pig & rabbit food all look similar. 
  • Rabbit feed with high fiber may be used to prevent obesity and GI obstructions. 
  • Guinea pig feed has Vitamin C added. 
  • Guinea pigs eat up to 35-60 g daily, rabbits will eat 100-250 g/day, but should be given no more than 120 g (4 oz or 1/2 cup) per day to prevent obesity. 
  • Excessive feeding of produce for enrichment may cause diarrhea. 

Water - Rabbits & guinea pig 

  • Sanitize all water bottles, stoppers, and sipper tubes weekly. 
  • Rabbits will drink up to 500 ml water daily, guinea pigs as much as 50-100 ml daily. 
  • Put at least 2 water bottles for rabbits and guinea pigs. 

Guinea pigs are messy drinkers and cages can get wet very quickly

HANDLING OF LABORATORY ANIMALS - MOUSE,RAT,HAMSTER,GUINEA PIG, AND RABBIT


Mouse

  • Wear gloves to prevent allergies. 
  • Catch and lift mice by the tail. 
  • Grasp the tail with the thumb and forefinger or by the used of smooth-tipped forceps. 
  • Place a second hand under their feet (for pregnant mice). 
  • Hold mouse by the tail and placed on a table or other surface and grasp the loose skin over neck and shoulders with thumb and fingers for a more control grasp.
  • Hold the tail or the tail and rear leg by the third and little fingers of the same hand or with the other hand to improve restraining.
  • Put back mice in cage by lowering it into the cage and release upon contact with bedding.
  • For mice less than two weeks of age, grasp by the loose skin over the neck and shoulder with thumb and forefinger or smooth tipped forceps.
  • Avoid handling neonatal mice.


Rat

  • Wear latex gloves to prevent the development of allergies due to direct contact with animal allergens. 
  • Place the hand into the cage to allow exploration by the animal prior to touching. 
  • Initial gentle stroking of the animal followed by gradual grasping the animal will prevent startling the animal and initiating an aggressive response. 
  • Avoid approaching the animal from the front.
  • Grasp the whole body with the pal over the back, with forefinger behind the head and the thumb and second finger under opposite axilla. 
  • Holding with one hand is usually adequate for control, but the tail, rear legs or lower part of body may be held by the other hand for close control, treatment or examination 
  • Use both hands for rats weighing over 350g. 
  • Young rats may be handled like mice when body size does not permit ease of handling within the hand. 
  • Avoid lifting by the tail as they may strip the skin from the tail. However, the "base" of the tail may be grasped with the thumb and forefinger.


Hamster

Method I
  • Form a cup with your hands and place it over the hamster.
  • Gently press your palms against the animal as you pick it up.

Method II
  • Grasp the loose fold of skin behind the neck with your thumb and index finger. Cup your other hand under the animal’s rump & grasp the hind legs between your thumb and index finger.
  • Carry the hamster in the same position in which you picked him up.
  • For injecting the animal in the mid section, merely stretch it out.

Caution: Always handle hamster over a bench or table because they are liable to jump from your grasp and injure themselves.

Guinea pig

  • Wear latex gloves to prevent the development of allergies. 
  • One hand is gently placed dorsally over the thorax or ventrally under the thorax and the other hand should be used to support the animals hindquarters. 
  • Do not to apply to much pressure over the thorax to avoid damaging the viscera or compressing the lungs thereby compromising respiration. 
  • After grasping the Guinea pig secure it by wrapping in a towel or holding against your body will lessen the frequency of struggle. 
  • Do not attempt restraint by solely grasping the skin. The lack of loose skin in Guinea pigs will result in hair depilation if this technique is utilized. 


Rabbit

  • Wear latex gloves
  • Held the rabbit in a way that directs their hind feet away from the handler's body.
  • Grasp the loose skin over the neck and shoulder with the head directed away from the holder is the best method of initial restraint. 
  • Support the lower part of the body by the the other hand to prevent serious injury to the rabbit's
  • Never restrained or lifted by the ears.
  • Immediately place the rabbit on a solid surface if it begin to struggle violently.
  • Complete restraint should be accomplished before attempting any procedures.

Wednesday, October 15, 2008

Blood Collection from Orbital Sinus in Mice


  • Should apply anesthetic before blood withdraw
  • A convenience and easy apply method for blood collection in mouse
  • Collect amount up to 0.5 ml

Tools for Blood Collection from Orbital Sinus in Mice

  • 75% alcohol cotton ball for surface disinfection
  • Hypnorm for general anesthetic
  • 27 G needle with 1 ml syringe for injection
  • Glass capillary tube and vial for blood collection

Anesthetize a mouse by intraperitoneal injection of Hypnorm



Use a sharp end glass capillary tube to penetrate the orbital conjunctiva and rupture the orbital sinus



Collect blood with a vial

Saturday, October 11, 2008

Blood Collection from Tail Vein in Mice


  • For collection of small amount of blood (Approximate 0.1 ml)

Tools for Blood Collection from Tail

  • 75% alcohol cotton ball for surface disinfection
  • Small plastic bottle with 1/2 cm diameter holes in both ends as mouse restrainer
  • Scissors
  • Pipetteman and tips
  • A vial for blood collection

Placing a mouse on a cage lid and grasping the loose skin behind the ears by the thumb and forefinger



Push the mouse into the restrainer



Leave the tail of the mouse outside the cover of the restrainer



Amputate the tip of the mouse tail by scissors



Massage the tail and collect blood by pipetteman




Wednesday, September 17, 2008

Mice in Research


Species
  • Rats, mice and other rodents: 90-95% · The remainder is mostly guinea pigs, hamsters, and rabbits.
  • Pigs, sheep, nonhuman primates, cats, dogs, and other animals are needed far less often.
  • Dogs and cats: less than 1%
  • Non-human primates: less than 0.3%.

Mammals have been widely used, because of their obvious similarities in both structures and function to man. Rats, mice, guinea pigs, and hamsters came into favor because of their small size, short life span, ease of handling, high reproductive rate.

Mice in research:
  • Along with rats and other rodents, mice make up the majority of animals used in medical research.

Advantages
  • Their small size and low cost makes them ideal for laboratory experiments. In addition, scientists can breed different strains of mice with natural genetic deficiencies to achieve specific models of human diseases.

Research
  • Cancer: Through breeding, researchers have developed mice with leukemia, breast cancer and many other types of cancer, allowing new treatments to be tested on animal models, instead of humans. Cells from human cancer tumors can be placed into immunologically deficient mice without rejection. This allows the study of human cancer without risking human lives. Studies with mice have shown that the immune system can be stimulated by genetically altered tumors, leading to hopes that gene therapy can be used to fight cancer.

  • Immunology: Scientists are searching continuously for a best animal model for the study of AIDS. Much that we know about the devastating disease has come from research using mice, allowing scientists to apply information gained from mice to humans suffering from AIDS.

  • Product safety: Mice, along with other rodents, are used in product safety tests, including measurements of the effects of long-term exposure of a product. Mice are also used to test a product’s safety on pregnant women and nursing babies.

Virology:
  • Research with mice helped develop vaccines to counter influenza, polio, yellow fever and rabies.
  • Mice were also used in studies that show that the host, as well as the agent, plays a major role in viral infections.

Fertility treatments: The successful transfer of human embryos is possible today because of experiments in mice. This technique can also be used to improve reproduction in domestic and endangered species.

Why Are Animals Needed in Research?

Historical Perspectives

The idea developed in ancient time.In early cultures, priests or shaman began to observe the relationship between human health and animal diseases (for example Judaic Law prohibiting the eating of pork).In Roman times Galen, the father of anatomy, dissected animals learning about their internal structures and then using them to teach others.Until the time of the American Revolution experimentation on animals begins.In Western Europe in the late 1700's an event of major economic consequence was in part responsible for the emergence of the research process as we know it today.


Rinderpest (a fatal plague of cattle) was introduced to Europe from southern Russia by returning soldiers. In a decade the disease swept westward and reduced the cattle herds of Europe "in orders of several millions." The first quarter of the 18th century had already witnessed a dynamic expansion of efforts to promote (human) medical sciences. There was wide spread public outcry about Rinderpest and other little understood and devastating epidemic diseases like anthrax, foot and mouth disease, and pleuropneumonia. These were threats to the economic existence of not only household but of countries. Remember that during this time the economic base of most European countries was grounded in agriculture. Rinderpest caused monarchs and governments of most European states to pressure their medical and scientific establishments for action. In France in 1762, we see the creation of the first Veterinary College at Lyon and it was based on the training already in existence in the study of human medicine. In Germany rural physicians were encouraged to obtain instruction in Veterinary Medicine, which at that time was a skilled trade like horse-shoeing is today.


In 1787, following the example of the French we see the creation of the Veterinary College at Berlin. In the 1800's noted researchers who came to be associated with this new interest in a holistic approach to biomedical research included: the Frenchmen- Claude Bernard, and Louis Pasture, Robert Koch of Germany. With animal research many disease-causing organisms were identified before the end of the century, as well as spectacular medical advances with such procedures as ether anesthesia and surgical antisepsis. In Europe and in the US by the early 1900's and especially during and following World War I the benefits of animal research continued to be recognized. Following the Nuremberg Trials for atrocities by the Nazi's during World War II, society spoke loudly demanding no research on humans until animal research had made such research a reasonable risk. Today, the majority of people in our society do agree with the idea of the humane and responsible use of animals in research.


Scientific Perspectives

There are 4 reasons why animals are used in research:

1. The principles of anatomy and physiology are true for humans and animals, especially mammals. Once scientists learned that animals were similar to humans, in physiology and anatomy, it became preferable to use animals rather than humans for preliminary research.

2. Certain strains or breeds of animals get the same diseases or conditions as humans. "Animal Models" are frequently critical to understanding a disease and developing appropriate treatments.

3. Research meant introducing one variable and observing the results of that one item. With animals we can control their environment (temperature, humidity, etc.), andshield them from diseases or conditions not related to the research (control their health). Although human and animals get the disease that may be the subject of a research investigation, the different life styles or living conditions make them poor subjects until preliminary research under controlled conditions has been done.

4. We can use scientifically-valid numbers of animals. Data from one animal or human is not research; it is a case study. To scientifically test a hypothesis, an adequate number of subjects must be used to statistically test the results of the research.


Some individuals claim that we should use human or animals that have a disease to study that disease. Certainly, epidemiological studies (tracking the occurrence of a disease or condition) have provided many important insights into the cause of a disease or a condition, especially when an environmental aspect is responsible. However, epidemiological studies are successful in only a limited number of situations. As noted earlier, the study of a disease is severely hindered or not possible when the research subjects have been/are exposed to a variety of environmental factors.


It is important to note that, according to the American Medical Association, humans are the most frequently used animal in research. However, research studies conducted on humans follow preliminary studies conducted in animals. These animal studies make human studies a reasonable risk. The animal studies are not a guarantee of success, but they do tell us that the human research has a reasonable probability of success.