What if parasites spread unchecked?

Parasites pose major challenges for cattle producers across the world. Not only do parasites such as flies and ticks, impact animal well-being and health, but infestations are costly for farms. The warming climate is creating ideal conditions and ‘new’ regions for parasites to thrive, which could expose cattle to new health risks, says Veterinary Scientific Affairs Manager at Bayer Animal Health, Dr Chandra Bhushan. He emphasizes that it is essential to customize parasite control programs and to use parasiticides judiciously.


Have you noticed flies emerging earlier in the year? How about ‘tick season’? These days, the risk of parasite infestations is no longer a matter of just a few months over spring and summer.   

Warming temperatures offer conditions that are more conducive for the development of parasites, such as ticks and flies. In fact, we are seeing ticks appearing in ‘new’ regions, while in endemic areas, extended spring and summer seasons provide more opportunities for these parasites to breed and multiply.


Parasites impact cattle well-being, health and productivity

Imagine hundreds to thousands of ticks or flies taking blood meals from a single cow, causing it significant discomfort, pain and stress. This would disrupt the cow’s natural feeding pattern, which translates to lower weight gain or even weight loss. Furthermore, these parasites can also be vectors of diseases that can debilitate or even kill the animal. This means that if cattle are not properly protected, parasites can also seriously impact productivity.

The movement of animals from one farm or area to another, or even across borders, also increases the risk of spreading vectors and vector-borne diseases in non-endemic areas, as well as resistant parasites. To minimize this risk, it is essential to ensure that cattle are, for example, tick-free before they are brought onto a new farm or area and mingled with an existing herd.

However, even if ticks are transferred to a new area, it is not a given that tick-borne diseases will also spread there. Prerequisites for that are conducive conditions that include the presence of the tick (vector) and the optimal conditions for their development, the animal (host) and the disease pathogen. Take, for example, the cattle tick called Rhipicephalus appendiculatus, which is found in South Africa and Kenya. This tick transmits East Coast Fever in Kenya, where the disease is endemic, but it doesn’t transmit the disease in South Africa because East Coast Fever doesn’t exist there.

Many countries have stringent measures to control the risk of diseases that are associated with animal movement across borders. Such measures include keeping animals in quarantine or conducting close inspections to ensure that they are completely tick-free before they are allowed to enter the country.



No one-size-fits-all parasite control program

Effective parasite control has to start on the ground, at farms. And because the conditions on the ground can be highly varied, the most successful parasite control programs are the ones that are tailored to address the farm’s specific needs.

There are non-chemical parasite control methods, such as pasture spelling that involves keeping certain pastures cattle-free for a period to interrupt the life cycle of ticks. The breeding of certain species of cattle, such as Zebu that have been found to be less attractive for ticks, is another approach.  

Parasite control programs may encompass a combination of non-chemical and chemical methods. But to date, chemical parasite control products – parasiticides – remain the most effective way to protect cattle from tick and fly infestations, and in turn vector-borne diseases. Parasiticides are available in a variety of different formulations and different application methods. It is vital that they are used appropriately.


Judicious use of parasiticides is essential

One of the biggest issues today is the growing resistance of parasites to chemicals in parasiticides, which is developing in ticks, lice and flies. There are reports where ticks have become resistant to all the available classes of parasiticides, making them much harder to treat.

This is why it is vital that parasiticides are administered judiciously to maintain their efficacy for the future. By understanding and using the right parasiticide in the proper dose, applying it at the right time and in the right way, and rotating products from different molecule classes, we have a better chance at preserving the effectiveness of these important products.

Bayer Animal Health has long been sharing its expertise with cattle professionals across the world to help optimize and tailor farm-specific parasite control programs. Digital tools, such as our ParaSight smartphone application, can also help as an information resource to aid cattle professionals’ efforts to combat infestations effectively and sustainably.

Together, we can combat parasites, and safeguard animal well-being and health at the same time.


Cattle on pasture