Merck establishes an animal health division and discovers sulfaquinoxaline, the first poultry coccidiostat.

Feed manufacturer Wim Hendrix lays the foundation for Intervet in Boxmeer (The Netherlands), where the Animal health headquarters of todays’ company remained until 2012.

Schering-Plough Animal Health is established and comes to market with prednisone to treat ketosis in dairy cattle.

Intervet develops first fowl pox vaccine for poultry

Publication of first edition of The Merck Veterinary Manual.

Netherlands based “Koninklijke Zwanenburg Organon” (which later became AKZO NOBEL) acquires Intervet..

Introduction of anti-inflammatory drug for horses (Schering-Plough Animal Health).

Launch of products for reproduction management in farm animals (Intervet). Development of anthelmintic fenbendazole (Intervet).

Development of first recombinant DNA vaccine (PORCILIS® Porcoli against diarrhea in piglets) by Intervet.

Development of florfenicol, a novel phenicol antibiotics exclusive to animal health (Schering-Plough Animal Health).

Introduction of antiparasitic SCALIBOR® a dog collar to prevent Leishmaniasis from sand fly bites (Intervet)

Merck and French pharmaceutical company Rhone-Merieux (later Sanofi) combine their animal health divisions in an equally-owned joint venture named Merial.

Launch of SLICE® fish antiparasitic for the treatment of seas lice in salmon (Schering-Plough Animal Health).

Licensure of the first live bacterial recombinant vaccine against strangles in horses in the EU (Intervet).

Introduction of PORCILIS® Pesti, the first marker vaccine for classical swine fever (Intervet)

Harrisvaccines was founded in Iowa

Schering-Plough acquires Organon Biosciences (Intervet and Organon) from AKZO NOBEL. The animal health division operates as Intervet/Schering-Plough Animal Health.

Development of Sphereon, freeze-drying technology for vaccines (Intervet/Schering-Plough Animal Health).

Merck & Co acquires Schering-Plough. Intervet/Schering-Plough Animal Health becomes the animal health division of Merck.

The operating name of Merck’s animal health unit changes to Merck Animal Health (MSD Animal Health outside the USA and Canada)

Merck Animal Health receives FDA approval of BRAVECTO™, the first chewable tablet for dogs for up to 12 weeks of treatment and prevention of fleas and ticks.

Merck Animal Health receives approval of PORCILIS® PCV M Hyo vaccine, Europe’s first single-shot vaccine to protect piglets from Porcine Circovirus Type 2 and Mycoplasma hyopneumoniae infections

Merck Animal Health receives a conditional product license for the Canine Influenza Vaccine H3N2 and becomes the first company to make the vaccine available to the market.

Merck Animal Health acquires Harrisvaccines, a privately-held company that develops, manufactures and sells vaccines for food production and companion animals

Merck Animal Health receives marketing approval from European Medicines Agency and U.S. Food and Drug Administration’s approval of BRAVECTO® for both cats and dogs, up to 12 weeks of treatment and prevention of fleas and ticks.

Merck Animal Health receives approval for conditional product license for CIV H3N2 vaccine to protect dogs against the newly identified strain of CIV