Saturday, 29 August 2015


There are main types of injection areas that every farmer should be able to perform.  The easiest is the subcutaneous injections and intramuscular injections.   Subcutaneous injections have a longer absorption period in general.  The diagram below shows the skin, subcutaneous tissue and the muscle.  Below the muscle is the bone.  The subcutaneous injections are administered in the subcutaneous tissue (below skin) while the intramuscular injections are administered in the muscle.

Figure 1 showing the anatomy of injection sites

Area of injection 
Vaccines – Always use the recommended specifications for the vaccine.  In most cases, both intramuscular and subcutaneous should be given in the triangular mass of the muscle on the neck.  Take caution to avoid the top of the neck, which contains a ligament, and the bottom portion of the neck where the bones, windpipe and jugular vein are located (see below).

Antibiotics – The neck is usually the preferred location. Be sure to split the dose into two areas.  Do not administer more than 15ml on one side.  If large volumes are injected into one site, the medication will be absorbed too slowly through the body or to the infected area.

Figure 2 depicting vaccination sites

How to administer subcutaneous injections?
  1. Make sure that the area for injection is clean and dry.
  2. Lift a fold of the skin on the neck or shoulder where the skin is the loosest, and slip the needle between the skin and muscle (fig 3).  This should be nearly parallel (at 45°) to the surface so the needle goes under the skin and not into the muscle (fig 1).
  3.  Release the vaccine with the required dose.  Remember to use half the dose on one side, and the other half on the other side if it’s a big dosage i.e if 30 ml of dosage is required, use 15 ml on one side of the cow and 15 ml on the other side of cow, both subcutaneously.

Figure 3 showing how to administer subcutaneous injection

How to administer intramuscular injections?
  1. Make sure that the area for injection is clean and dry.
  2. Pat and stroke the spot where the injection will be administered to reduce sensitivity and irritation and keep animal from flinching.
  3. Thrust the needle in quickly and forcefully so it goes through the skin and all the way to the muscle.  If the animal jumps, wait till it settles down before attaching the syringe to the inserted needle to give the injection.  Be sure the needle used is not too long as this could penetrate through muscle and to the bone, which could be extremely painful.
  4. If the needle oozes blood, you have hit a vein.  Take out the needle and try again on a slightly different spot.  DO NOT INJECT AN INTRAMUSCULAR PRODUCT INTO A VEIN.
  5. After injecting the product into the muscle, rub the injection site to help distribute the product within the muscle.


Friday, 21 August 2015


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.