Latest Data Confirm Imidacloprid Remains Highly Efficacious After More Than a Decade of use

New Publication From International Experts Demonstrates Fleas Worldwide Continue to be Highly Susceptible to Imidacloprid

MONHEIM, Germany, December 13, 2010 - In a study published online last week in Medical and Veterinary
Entomology, international experts reported the latest data on flea
susceptibility to imidacloprid, revealing that after more than a decade of
widespread use around the world, there is no evidence of resistance to this
invaluable treatment.

The study looked at data compiled between 2002 and 2009 by the
International Flea Susceptibility Monitoring (FSM) programme from monitoring
centres in Australia, Germany, France, UK and USA. The data showed that, of
the more than one thousand samples tested over the past eight years, all were
confirmed to be susceptible to imidacloprid.

"These results are great news for veterinarians and pet owners
alike," said Dr Byron Blagburn, Distinguished University Professor, College
of Veterinary Medicine, Auburn University, USA. "They show that imidacloprid,
one of the most widely used active ingredients for flea control in pets,
remains as effective against fleas now as it was when it was first launched."

Imidacloprid is the key active ingredient in Advantage(R) and
related products developed for the effective control of fleas and other
parasites in companion animals.

The International FSM programme is the first and only
monitoring initiative in the field of companion animal parasites. The FSM
initiative includes a group of internationally renowned, independent
researchers who work together with Bayer Animal Health to monitor the
susceptibility of fleas to imidacloprid.

"In order to prevent resistance to treatments such as
imidacloprid, careful and coordinated monitoring is essential in order to
detect as early as possible any potential shifts in susceptibility. The FSM
programme is unique in terms of geographical scale and duration. It is an
excellent example of a pharmaceutical company collaborating with academic
organisations to ensure the efficacy and safety of its products," said Ian
Denholm, Principal Scientist, Rothamsted Research, Harpenden, UK.

Bayer Animal Health supported the initiation of the FSM, in
partnership with an international panel of experts, in order to monitor the
susceptibility of flea populations to imidacloprid, the active ingredient of
Advantage(R). "We are delighted to see that, once again, the data from the
FSM programme show that veterinary professionals and pet owners can continue
to trust Advantage(R) to provide effective, reliable flea control for
companion animals," said Sarah Weston, Global Veterinary Services Manager at
Bayer Animal Health.

About the Flea Susceptibility Monitoring (FSM) program

The FSM is a large-scale international program based on a
monitoring methodology which utilises flea eggs collected from the field in
the US, Germany, UK, France and Australia. Egg collection is carried out by a
network of veterinarians and the samples analysed in four investigating
laboratories based in three countries. The FSM was set up in 1999 and to date
has not detected any reduced susceptibility to imidacloprid. A dedicated team
of 15 people including independent experts in veterinary parasitology,
entomology and molecular biology, in addition to Bayer personnel, work
together to manage the FSM program.

About Bayer HealthCare

The Bayer Group is a global enterprise with core competencies
in the fields of health care, nutrition and high-tech materials. Bayer
HealthCare, a subgroup of Bayer AG with annual sales of more than EUR 15.9
billion (2009), is one of the world's leading, innovative companies in the
healthcare and medical products industry and is based in Leverkusen, Germany.
The company combines the global activities of the Animal Health, Consumer
Care, Medical Care and Pharmaceuticals divisions. Bayer HealthCare's aim is
to discover and manufacture products that will improve human and animal
health worldwide. Bayer HealthCare has a global workforce of 53.400 employees
and is represented in more than 100 countries.

Find more information at www.bayerhealthcare.com.

With a turnover of EUR977 million (2009) Bayer HealthCare's
Animal Health Division is one of the world's leading manufacturers of
veterinary drugs. The division manufactures and markets more than 100
different veterinary drugs and care products for livestock and companion
animals.

Forward-Looking Statements

This news release contains forward-looking statements based on current
assumptions and forecasts made by Bayer Group management. Various known and
unknown risks, uncertainties and other factors could lead to material
differences between the actual future results, financial situation,
development or performance of the company and the estimates given here. These
factors include those discussed in our annual and interim reports to the
Frankfurt Stock Exchange and in our reports filed with the U.S. Securities
and Exchange Commission (including our Form 20-F). The company assumes no
liability whatsoever to update these forward-looking statements or to confirm
them to future events or developments.

    Contact: 

    Kathrin Statz, +49-2173-384019
    kathrin.statz@bayerhealthcare.com

Kathrin Statz, +49-2173-384019, kathrin.statz at bayerhealthcare.com