Biosecurity refers to protecting the health of our livestock by preventing disease transmission. The extreme happened many years ago now regarding the spread of foot-and-mouth through Britain. A more likely example would be the spread of scours from farm to farm or from pen to pen within the farm itself. This article will try and deal with a practical approach to on-farm biosecurity. It will explain what most producers should be doing as a preventive. Hopefully I will dispel some false myths.
Every few years a severe outbreak of scours or some other disease will get the community talking; the fear of spread is the biggest concern. Often producers are afraid to even associate with their neighbours in such a situation. I have coined this the “leper mentality.” They treat the producer involved like they have leprosy.
A few very simple precautions can virtually eliminate the possibility of any transmission and make producers rest easy.
Firstly, the first form of any biosecurity is having your stock as well protected against any disease of concern. Work with your veterinarians. They know the diseases prevalent in the area. Vaccines for most common contagious diseases such as scours, IBR or BVD already exist. For other diseases less prevalent, such as leptospirosis or anthrax a reportable disease, veterinarians may have you vaccinate if the disease emerges in your area.
Good nutrition also keeps the immune system strong. Keep in mind no vaccine is 100 per cent protective and in the event of overwhelming challenge disease can still occur. Treating and removing external and internal parasites also keep the immune system strong because it is not trying to rid the cattle’s body of these pesky parasites.
A very common-sense approach to disease control is the best, as these steps are easy to implement and maintain. Infectious organisms are small, generally much smaller than what the naked eye can see. A good rule of thumb is anything dirty may be contaminated with infectious organisms. Either your clothes, skin, or more commonly boots, can be the biggest source of infection. Cleaning clothes, removing coveralls and washing boots with common disinfectants after contacting sick animals will kill or remove most organisms.
Simply cleaning your hands is a good hygienic practice minimizing spread of disease. Boot dips with a disinfectant such as VIRKON or water and vinegar mixed 50-50 allows one to disinfect the soiled underside of boots as well as make a visible statement to visitors that sanitation is very important on your farm.
If possible have a garden hose there with pressure.
However, visitors should be coming to your place with clean boots and clothes. With visitors, it may be best to have extra pairs of boots they can wear or have a box of the slip-over plastic boots that can be worn over their existing footwear. This also really increases awareness of the importance of biosecurity on your farm.
Having a boot dip with brush at the entry to your farm or calving barn, for instance, is a constant reminder of biosecurity. These boot dips should be replenished at weekly intervals or sooner if lots of organic material are present. Disinfectant mats are also available which accomplish the same purpose.
The potential for disease introduction is greatest when new animals are purchased or if your own animals are taken somewhere (like to a cattle show or auction market) and then returned home. A simple fix here is to isolate these animals for two to three weeks when you return, as most diseases picked up will express themselves by then. Contrary to this some natural exposure to infectious diseases in this way could be a good thing as it makes your herd more immune competent.
A totally closed isolated herd is really a misnomer in today’s cattle industry. Cattle are traded back and forth, taken to auction markets and brought home and, as a minimum, herd bulls are purchased off farm. Plus, there is exposure to wildlife and humans, which can occasionally be a source of infection for your cattle.
Most purebred operators have very open herds. Heifers and bred cows are purchased and sold. Commercial producers are always walking through the herd selecting bulls. Cattle are taken to shows exposing them to numerous other cattle by direct and indirect contact.
As mentioned before, this could still be a good thing potentially allowing limited exposure to some organisms. It is when the concentration or exposure to organisms gets too high that disease occurs. One always has to be wary when stress from transport, processing, weaning or calving gets too high, as cattle are much more susceptible to pick up disease.
Mechanical transmission from people, vehicles and other equipment is another mode of transmission. Visitors from urban areas are less of a risk, but again maintaining cleanliness, boot dips and simply not allowing access to certain areas of your farm at certain times of year minimize any risk. Most infectious viruses are quite fragile; drying by the sun kills most germs.
Wildlife still pose some threat to our commercial cattle when it comes to certain diseases. They are very mobile, cover great distances, and are hard to control. You want to control wildlife, especially cloven-hoofed animals, from access to your feed and water supplies. This prevents fecal and urine contamination.
If potentially contagious diseases are diagnosed in your area, the intensity of these control problems can be stepped up and visitor logs used. Work with your veterinarian to have the most comprehensive vaccination program you can. If you help the neighbours, such as with branding, clean your clothes and boots upon returning. By implementing the above points you can minimize most potential biosecurity risks against your farm.