HOW DO VACCINES WORK?

As farmers, we often have to give our cattle vaccines to prevent diseases.  Often, farmers ask what vaccines to use for what disease, but it is very important to know and understand how vaccines work and what their functions are.

What is a vaccine? what is the purpose? how do vaccines work?

A suspension containing live, modified or killed micro-organisms or toxins.  This suspension, when administered stimulates the animal’s immune system to produce antibodies/antigens which help fight the disease, should the disease occur.  For example, we are often told to vaccinate our herds against anthrax annually.  What the vaccines do, they contain anthrax causing organisms in the ‘harmless’ form that the body can fight against.  And in the process, when there is an outbreak of the disease, the body already recognizes the disease and has developed antibodies already to fight off the disease.

Boosters and immunity time frame

Vaccines give different lengths of immunity. Some vaccines such as the Brucella S19 which fights against the Brucella virus in heifers is only given once because it has a long term immunity response.  Most vaccines are reapplied every year as the immunity only last for a year.  This is what is called boosting (boosting animal’s immune system) i.e Supavax for anthrax, Blackleg/black quarter and botulism. The function of the booster is to optimize the effectiveness of the vaccine, by maximizing the possibly of the fight against disease. 

Colostrum is the thick milk that comes during the first few days after a cow has given birth.  This milk is very important, and it is always required that the cow should suckle.  Colostrum contain antibodies that the mother has produced, and this gets transferred to the calf and help with disease fighting.  As part of your management plan, insure that calves suckle colostrum. The process is passive immunity.

Why vaccines fail?

Sometimes vaccines fail.  There are several reasons why vaccines fail.

Improper administration

Dosage - wrong dosage may result in vaccination failure.  Always use the recommended dosage when vaccination cattle.  Some vaccines, the dosage is expressed in ml/kg of animal weight.  If the recommended dosage is 1ml/10kg of an animal, than the dose is 30ml for a weight of 300kg.  Using less will result in vaccination failure.

Area of vaccination – There are 3 main areas of vaccination.  Mainly, subcutaneous (SQ on some labels) is when you vaccination through the skin, between skin and flesh. The intravenous injections are giving through the vein (usually by very experience people/VET), and finally, intramuscular (IM) injection which is given through the muscle.

Needle hygiene – Using dirty needles will result in vaccination failure.   Always sterilize needles and syringe by boiling in water (for at least 15 minutes). 

Improper mixing of vaccines

Different pH and dilutents – could completely alter the chemical composition of the vaccine. 

Improper timing

Too early – if vaccines are given too early in calves, they will interfere with antibodies that were passed on from the mother to the calf via the colostrum. So follow directions on the vaccination label on what age to vaccine.

Too late - the disease is already in process.  Other vaccines such as antibiotics must be given.  Give the vaccines that help fight the disease, not the once that prevent the disease.

Animal factors

Environmental stress – animals that are stressed have weak immune systems.  As a result, vaccines that prevent diseases are not effective. Stress such as little grazing (in overstocked farms), long distance travel to drink water, climate change (no rain) all effect animals.

Transport - cattle movements from area to area is very stressful for animals.  If vaccinated, this could result in vaccination failure.

Weaning stress - Never vaccinate with weaning. This reduces the effectiveness of vaccine.  Vaccinate either before or after weaning.

Storage – improper storage, especially for live vaccines can destroy active ingredients, causing vaccination failure.  Store vaccines as instructed, keep away from direct sunlight, keep the temperature as recommended.

Use after expiration – will reduce effectiveness of vaccine.

xOxO

RECORD KEEPING IN BEEF PRODUCTION SYSTEMS

The recording of livestock should not be taken for granted.  Every farmer should use this practice.  Records are not only used to identify animals, but also to select animals based on production levels.  As a farmer, we want animals that are productive and yield a calf every year (or as often as possible). 

    Adapt a record system that is suitable for your production type.

  Beautiful herd drinking water.

They say a record system should only include data which can be used.  But I say, it’s better to have as much data as possible.  Perhaps, in the future, a great use for the data will be established.

The type of record one collects depends on what production system or line of farming one is involved in.  The diary farmer will have much different record than a beef producer (which can further be oxen production systems, weaner production systems etc).

I really suggest that as a farmer, YOU sit down and think long and hard what data you need to record. 

The following are the registers that I keep on the farm:

1. Cow register and breeding/mating register and   vaccination register in one.

·         The main aim of my cow register is to be able to check the productivity of a cow.  Immediately.  When a cow is not productive, I can determine that from my records and waste no time in getting rid of her.

·         Record the ear tag.  Every tag is unique for every cow.

·         If the cattle are serviced by a bull, I indicate the month of service so I know when the calf is due. 

·         Amazingly.  Cows usually tent to give birth during round about the same time of the year.  For every cow, I know when to expect a calf.  Really good for planning purposes.

·         I regularly vaccinate against anthrax, black quarter and botulism.  I give inject able vitamins as well.  This is recorded on the cow register. I also keep record of animals with other problems such as udder problems, joint ill problems.  And the treatment of such cases is recorded too.

2.  Calve register and vaccination record

·         This is the record of all the calves in my herd, together with age, dam and sire, ear tag number and sex.

·         The date the calves are born is also important for recording (for breeding and weaning purposes).  I do not have breeding camps.  Therefore, I have a yearly production of calves.  I have divided by production cycle in 3 quarters of the year (January – April is quarter one, May – August is quarter two, September -December is quarter three).  I make sure I go to the farm at the end of every quarter (April, August and December) to conduct a thorough assessment on all my livestock.  I wean, vaccinate, dehorn, brand, tag and castrate in every quarter.  Remember not to wean and vaccinate, brand, dehorn at the same time.  This causes excessive stress on the calves and their heath weakens.

·         At one of these quarters, before weaning I vaccinate against brucellosis (which is mandatory for 4-11 months old female calves).

·         After every quarter I submit my ear tag information to Meatboard for recording into the Namlits database.

3.  Tolly or oxen register and vaccination register

4.  Heifer register and vaccination register

·         I consider a heifer anything female of the ages between weaning and bull servicing. I have a separate record book for this category.

·         I also vaccinate annually against anthrax, black quarter, botulism and inject able vitamins.

Templates are all over the net that can help you.  Some people used computer software tailor made for their needs. 

Recording is a good practice.  It saves me money and time.  Most importantly I can plan ahead. I can do some stuff without actually being at the farm. 

XoXo