A simple guide to usage and storage of veterinary drugs

To keep livestock healthy, it is important to adhere to recommended treatment, which should be done by a trained veterinary personnel or experienced farmers.

There are several veterinary drugs administered through different routes.

They include vaccines, antibiotics for treatment of bacterial diseases, antihelmintics for treatment of worms, hormones for infertility or used as growth prompters and acaricides for treatment and control of external parasites.

Let us consider some of the major drugs, their importance, handling and the dangers that can result from their improper use.

Antibiotics and de-worming drugs

They are used to treat various diseases such as pneumonia, diarrhoea, anaplasmosis, East Coast Fever and mastitis. These drugs should always be administered by trained veterinary personnel who will ensure only the right dosage and combination is used.

A number of drugs used in animals are also used in human beings with a variation only in concentration and dosage. To ensure safety and health of animals, the following must be observed:

1. Correct dosage (amount used) and administration in the appropriate species

Administration of the right dosage of a drug ensures that its amount in the body of the treated animal is high enough to kill all bacteria or parasites causing the disease. Since drugs spread to all parts of the body, large heavy animals need more of the drug than light, small ones. The problems associated here include:

a.Under-dosage: When less than the recommended dose is administered, the strength of the drug is low and kills none or only some of the bacteria or parasites. Under-dosing leads to no cure, or an incomplete cure where the animal first improves but then relapses.
This results into drug resistance where the medicine no longer works and can be very frustrating to a farmer.
This is a common problem with de-wormers. For this reason, some de-wormers no longer work and farmers have serious problems treating their livestock.

b. Over-dosage: This is a serious problem and should be avoided at all costs because it can result in death of animals or non-reversible damage to body tissues where the drugs find their way and the farmer will have problems that might be very difficult to deal with.

c. Use of expired drugs: Expired drugs will not give the desired effect because they have already lost their strength. They can also cause harm to animals. Such drugs should be properly disposed to avoid environmental pollution.

d. Medicine meant for a particular animal such as cattle may cause harm and unintended reactions to animals of another species such as dogs and cats.

e. Some people can get allergic reactions following exposure to some veterinary drugs either through improper handling or handling animals that have recently been treated. Ensure proper handling.

2. Observe withdrawal period: This is the time until all toxic and harmful substances have been cleared from the animal’s body (including from meat and milk) of the treated animal.

This has two important aspects. First, veterinary drugs contain substances which are potentially toxic and harmful to humans. After giving a drug to an animal, these substances remain in its body for some time until they have been completely excreted.

Thus, they can be found in the muscle (meat) and also in the udder (milk).

If more than one injection has been given, the withdrawal period begins after the last treatment. For milk its 48hours while meat two weeks. Before the withdrawal period is over, milk from the treated animal must not be consumed and the animal can also not be slaughtered for meat.

VACCINES

Vaccines are active or inactivated disease organisms used to boost immunity of the livestock against specific diseases. Application of vaccines is a cheap way of protecting your flock against devastating diseases that cannot be treated and can kill all the chicken, or cattle in an entire flock. Such diseases include Newcastle, gumboro, and foot and mouth.

Using vaccines

Vaccines should be kept chilled in a fridge or frozen (depending on manufacturers’ instructions) as they deteriorate rapidly and loose efficacy within hours when exposed to warm temperature.

Once a vaccine vial has been opened, the whole contents should be used quickly. Unused vaccine remaining in the open vial cannot be kept for later use. It is advisable for several farmers to team up and have their animals vaccinated together on the same day to cut costs.

Vaccines should be handled and administered by trained veterinary personnel. Chicken vaccination by eye-drop against Newcastle disease can be administered by trained farmers.

Vaccines should be used only on the intended species and at the right dosage, otherwise they may cause adverse harm or reactions if wrongly administered.

And as you use the drugs….

Work with your veterinary doctor to identify the best ways to stop or treat diseases. Ensure that your plan includes all the medicines you are using and those incorporated in medicated feeds.

Only buy enough of the appropriate medicine necessary for current use. You should not pile up stock of medicines on the farm. Remember that it is illegal to sell or pass on medicines to anyone unless you are authorised to do so.

Read instructions carefully, including safety instructions, and make sure that you understand them before administering any medicine.

Keep records of all medicines, including feed premixes administered to your animals.

Avoid unnecessary use of medicines, treating animals only when you are absolutely sure it is necessary.

Store all medicines safely. in accordance with the instructions on the label. If they are being stored in a fridge, you should ensure that the temperature is checked regularly and is between 2 and 8 degrees Celsius. Where medicated feed is stored on farm, the feed bins should be clearly labelled with a description of the contents and their expiry date.

Make sure that your medicines are stored securely, under lock and key. Keep them in their original containers, clean and out of the reach of children, animals or anyone not supposed to handle them.

Dr Maina works at the Faculty of Veterinary Medicine and Surgery, Egerton University [email protected]