Specific Pathogen Free is a term used for laboratory animals that are guaranteed free of particular pathogen

Pathogen

A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...

s. It is always accompanied by a list of the absent pathogens.

Use of SPF animals ensures that specified diseases do not interfere with an experiment. For example, absence of respiratory pathogens such as influenza

Influenza

Influenza, commonly referred to as the flu, is an infectious disease caused by RNA viruses of the family Orthomyxoviridae , that affects birds and mammals...

 is desirable when investigating a drug's effect on lung

Lung

The lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...

 function.

Completely germ free

The animals can be born through a caesarian section then special care taken so the newborn does not acquire infections, such as use of sterile isolation units with a positive pressure

Positive pressure

Positive pressure is a pressure within a system that is greater than the environment that surrounds that system. Consequently if there is any leak from the positively pressured system it will egress into the surrounding environment....

 differential to keep all outside air and pathogens from entering. Everything that needs to be insterted into the isolator, such as food, water and equipment needs to be completely sterilized and disinfected, and insterted through an airlock that can be disinfected before opening from the inside.

A disadvantage is that any contact with pathogens may be fatal. This is because the animals have no protective bacterial flora

Bacterial flora

The bacterial flora is the community of bacteria that exists on or in the body but which are not part of the body and so exists in its own biochemical environment:*Exogenous bacteria*Flora *Gut flora*Human flora*mouth flora*Skin flora...

 on the skin

Skin

-Dermis:The dermis is the layer of skin beneath the epidermis that consists of connective tissue and cushions the body from stress and strain. The dermis is tightly connected to the epidermis by a basement membrane. It also harbors many Mechanoreceptors that provide the sense of touch and heat...

 or in the intestine

Intestine

In human anatomy, the intestine is the segment of the alimentary canal extending from the pyloric sphincter of the stomach to the anus and, in humans and other mammals, consists of two segments, the small intestine and the large intestine...

 or respiratory tract

Respiratory tract

In humans the respiratory tract is the part of the anatomy involved with the process of respiration.The respiratory tract is divided into 3 segments:*Upper respiratory tract: nose and nasal passages, paranasal sinuses, and throat or pharynx...

, and because they have no natural immunity

Immunity (medical)

Immunity is a biological term that describes a state of having sufficient biological defenses to avoid infection, disease, or other unwanted biological invasion. Immunity involves both specific and non-specific components. The non-specific components act either as barriers or as eliminators of wide...

 to common infections as they have never been exposed to them.

SPF

To certify SPF, the population is checked for presence of (antibodies against) the specified pathogens.

For SPF eggs the specific pathogens are:
Avian Adenovirus Group I,
Avian Adenovirus Group II (HEV),
Avian Adenovirus Group III (EDS),
Avian Encephalomyelitis,
Avian Influenza (Type A),
Avian Nephritis Virus,
Avian Paramyxovirus Type 2,
Avian Reovirus S 1133,
Avian Rhinotracheitis Virus;
Avian Rotavirus;
Avian Tuberculosis M. avium;
Chicken Anemia Virus;
Endogenous GS Antigen;
Fowl Pox;
Hemophilus paragallinarum Serovars A,B,C;
Infectious Bronchitis - Ark;
Infectious Bronchitis - Conn;
Infectious Bronchitis - JMK;
Infectious Bronchitis - Mass;
Infectious Bursal Disease Type 1;
Infectious Bursal Disease Type 2;
Infectious Laryngotracheitis;
Lymphoid Leukosis A, B;
Avian Lymphoid Leukosis Virus;
Lymphoid Leukosis Viruses A,B,C,D,E,J;
Marek's Disease (Serotypes 1,2, 3);
Mycoplasma gallisepticum;
Mycoplasma synoviae;
Newcastle Disease LaSota;
Reticuloendotheliosis Virus;
Salmonella pullorum-gallinarum ;
Salmonella species;

Minimal disease status

When by accident some infection does occur, the population is said to have minimal disease status.

External links

• Handling of SPF-Eggs (Lohmann Tierzucht ltz.de)