The absence of significant pathogens, and the diseases they cause, implies healthy stock and a healthy product. Risk management is not limited to economics and money management. Risk management with regards to herd health, can be translated into bio-security.

As producers continuously attempt to increase herd size and efficiency through the purchase of animals to broaden the gene pool of having heifers professionally raised by contracted growers, they risk the introduction of new diseases to their farms.

The goal of bio-security on a farm is to:

• Minimise the introduction of disease onto the farm
• Limit the spread of diseases already on the farm
• Reduce the risk of disease carried between farms

Bio-security management practices are designed to prevent the spread of disease by minimising the movement of biological organisms (bacteria, viruses, parasites, etc) and their vectors (rodents, flies, etc) onto and within the dairy through animals, personnel and other means. Bio-security can be accomplished by implementing a few basic concepts:

• Vaccination to increase the herd’s immunity
• Elimination or control of existing diseases of the herd
• Prevention of herd exposure to new infections by appropriate testing and pre-arrival management
• Application of basic sanitation and hygiene
• Training and skills development of staff

Dairy farms historically base contagious disease concerns around Brucellosis and Tuberculosis. However mastitis, which is a significant economic disease, tends not to be treated as the serious contagious disease it really is. A few management practices to minimize mastitis transmission in a dairy herd include:

• Milk infected animals last
• Keep sick animals and cows that are fresh in milk separate
• Separate infected animals from healthy animals
• Treat every cow with a dry cow intra-mammary preparation at drying off
• Treat clinical mastitis cases timeously and aggressively with the correct antibiotic and ensure bacteriological cure
• Test for mastitis prior to the milking process (strip cup, CMT, Mastest)

Vaccination is arguably the most essential component of a disease control strategy. It increases the animal’s ability to resist disease (stimulate immunity). It is important to determine the diseases to vaccinate against; which animals will benefit from vaccination and when those animals will require protection from vaccination. Even when properly administered, vaccines have limitations.

Thus producers should be aware that the immune status of the animal dramatically affects the success or failure of a vaccine. It is therefore essential to contact your herd veterinarian to set up a customised and strategic vaccination programme for your farm. Vaccination of animals should best be avoided shortly after periods of stress (e.g. weaning, heat, etc.).

The only effective way to combat disease is to know the cause and origin thereof. It thus makes sense to have any animal that dies unexpectedly on your farm examined by a veterinarian to determine cause of death and to prevent future occurrences, which may be achieved by adaption of a management practice. To prevent a herd from exposure to imported diseases, every new arrival on the farm should be tested for Bovine Viral Diarrhoea (BVD) and mastitis caused by the pathogens Staphylococcus aureus, Streptococcus agalactiae and Mycoplasma bovis as well as other prevalent and/or local potentially dangerous diseases.

It is critical to have a written bio-security control programme to communicate your commitment to everyone resident or entering your farm including the vet, herdsman, milkers and the milk truck driver so that they can adopt good sanitation, hygiene and bio-security practices. The future health of your herd and the economic success of your dairy depend on it.

Bayer Animal Health supplies Mastest, a product for the early detection of mastitis. It is based on the increased white blood cell concentration of mastitis infected milk. When mixed with Mastest the cells will form a gel and the degree of gelling is an indication of the severity of the infection and inflammation. Penstrep DC is an intra-mammary infusion suitable for cows being dried off and Penstrep 300D is for the treatment of clinical mastitis.

This article was compiled by Barry Schoombee, Product Manager (FAP), Bayer Animal Health

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Contact details

For more information on how your farm can benefit from Bayer Animal Health’s products, contact Bruce Collins at:

Email: [email protected]

Website: www.bayeranimalhealth.co.za