Your livestock may look healthy but suffer from internal parasites infestation such as worms. Common parasites include roundworms, tapeworms and flukes.

If not treated, worms compete and drain the animal of crucial nutrients resulting to poor health, slow growth rate, low productivity, poor conception rates and unhealthy young ones being born. Animals reared for meat will have parts of their carcass condemned at slaughter because of worms.

SYMPTOMS OF WORMS
A regular deworming schedule alongside good overall herd management should be practised to control significant parasitic infections that affect livestock. Where regular deworming is not practised, recognising the symptoms of worm infestation helps.

Infected animals show drop in production because worms deny them the full benefits of nutrients. They display poor physical appearance such that the ribs become conspicuous and coats dull and rough. Under heavy infestation, affected animals may become anaemic and develop oedema. They further become restless, experience hair loss, mineral imbalances and diarrhoea leading to dehydration.

They also have difficulties consuming and digesting feeds thereby giving loose, foul-smelling stool. Such animals will also cough and have distended abdomens. If on the extreme, the animal may die.

Young animals are typically more susceptible to internal parasites than older ones. The older cattle have developed immunity having been frequently exposed previously to the parasites.

The older animals, however, experience the harmful side of internal parasites as they near giving birth because immunity is suppressed. Bulls are also more susceptible to internal parasites than cows because they start grazing early.

CONTROL OF WORMS
An animal must first be dewormed when it is two to four months, or at an average of three months. Deworming interval depends on the de-wormer used but most drugs in the market recommend after every three months.

Several methods can be used to defeat worms. As long as animals continue to graze on pasture, internal parasites will always raid them.

The amount of parasites will, however, vary with pasture season and management. Good pasture management practises will save the animals’ the burden of parasites.

The management include grazing younger animals on safe pastures that have not been grazed on for almost 12 months as well as feeding them on small grain feeds. Always deworm animals before placing them on safe pastures. The less susceptible mature animals can be left to graze on the other pastures.

In addition, do not overgraze pastures. Animals feeding on overgrazed pastures are forced to graze closer to the ground hence pick up more larvae.

De-wormers (anthelmintics) provide another excellent way of controlling internal parasites. They are in tablet forms or as drench and other oral liquids.

Tablets require use of a bolus gun while the liquid suspensions need that you have a drenching gun or syringe.

The use of de-wormers, though, should not aim at treating infected animals showing signs of parasitism. Instead, apply de-wormers on time to reduce infection before symptoms occur.

Treatment should also aim at interrupting the life cycle of the internal parasite in an effort to minimise pasture contamination. De-wormers for treatment are normally selected based on ease of application, whether broad spectrum, milk withdrawal periods and cost-effectiveness.

The de-wormers are grouped into either avermectins/ milbemycins like Ivermectin or benzimidazoles like Albendazole. Avermectins/ milbemycins curb both external and internal parasites, as well as offer persistent protection for days to weeks after treatment.

Before application, always read and follow the instructions and prescriptions. These prescriptions are mainly important because they describe the best and safest level of control.

Under-dosing can reduce the level of control and make the parasites become resistant to de-wormers.

Overdosing, on the other hand, can poison the animals and lengthen withdrawal periods for products. Again, it is costly since it means spending more on de-wormers though it provides the same rate of control as recommended levels.

In a herd of dairy cows, deworming at early lactation consistently increases milk yields more than any other time of treatment.

Another option is to deworm all the cows in the herd at once then again after about three months depending on the drug used. Use only anthelminths approved for use in lactating dairy cattle, and consider milk withdrawal times.

Some de-wormers are not recommended for treating pregnant animals, if used they can cause miscarriage; therefore be sure of the choice of de-wormer.

Generally, it is advisable to reduce the animals’ access to feeds, especially fresh pasture but not water 24 hours before administration.

This will slow down the exit flow of the rumen and increases the time that the anthelmintic remains there and get absorbed. For the same reason, do not feed the animals for about six hours after drenching.

For successful deworming, ensure the drenching gun is well calibrated. Shake the liquid suspension thoroughly before administration and draw into the gun the recommended dosage as per body weight. Drench and ensure that the animal swallows the whole dose.