Management of the farm’s biosecurity
Adapted from the presentation of Alex Ramirez, PHD veterinary science, master of public health care of Iowa State University
Economic losses from porcine diseases account 20% of products costs in developed countries and 40% in developing countries. That is why biosecurity on pig farms is one of the most serious challenges of the modern pig production. Alex Ramirez is sure that the list of biosecurity measures differs from enterprise to enterprise as each farm has its own peculiarities. But there are common measures of prevention and eradication of diseases.
There are two aspects of health problem prevention: external (not to let the invasion of pathogens to the heard from the outside) and internal (to localize the disease inside the heard and prevent its further spread). It is definitely not possible to eliminate all the risks, but it is quite possible to minimize. This is the main task of the management of biological risks in pig farm. The disease appears when three factors are combined:
causative agent (viable and in sufficient quantity to cause a problem) a group of animals susceptible to the pathogen way of transmission of causative agent to animals
To avoid diseases the producer must break the connecting link between those three factors in the same time.
Special attention should be paid to ways of transmission of the diseases. There is a typical way of transmission for each causative agent. Their analysis helps to organize the most effective measures of biosafety. American pig producers distinguish seven main ways of the transmission of diseases (airborne, oral, reproductive, through direct contact of animals, inventory and transport). To define the most typical way of transmission for one or another agent the term Infection Doze 50(ID50) is used. ID 50 — is a minimal quantity of viable pathogens needed for one or another way of transmission to cause disease in a half of the analyzed group of animals.
Not all the pathogens may be spread airborne. This type of transmission is typical for Aujeszky’s disease, bacteria that cause some types of mycoplasmosis. Actinobacillus Pleuropneumonia may be spread only on short distances. The speed of Porcine Reproductive & Respiratory Syndrome spread depends on its strain.
Airborne transmission of pathogens depends on many other factors.
This way of transmission is fostered be the following factors: low air temperature(most pathogens are destroyed under the hot temperatures) , high humidity (pathogens stay alive for longer time and due to the attachment to water particles they are able to move on longer distances), flat area (in mountainous area air flow are broken against the rock mass, the air flow changes and the concentration of pathogens in the air decreases) and the absence of strong winds(if the air flows fast enough the causative agents have no time to fixate). For instance the outbreaks of PRRS in Iowa State usually take place in in winter times as winters are usually frosty and the landscape is flat.
What distance between farms protects from airborne spread of diseases?
Who may be blamed for the inventory transmission of diseases?
Why should such an easy procedure as shower not be neglected?
Why does the system of different colors of clothes and shoes work effectively?
Why shouldn’t «very healthy» and «very ill» pigs be housed together?
What are the peculiarities of vector transmission of diseases?
What is an easy rule to calculate the right quantity of rodents on the farm?
What details must be taken into account when designing a farm to avoid transport transmission of the pathogens?
What water is better for washing: hot or cold?
You can read more in the magazine publication «Profitable Pig Production», № 3 (9), 2012