About Animal Health International

It Started with a Conversation

Watch this video to hear how Animal Health International has grown from a conversation started 100 years ago.

Willard Wall opened a sundries store in Porterville, California (which would later transition into Walco International)


Willard Wall opened Livestock Supply, and expanded into Visalia, CA and Phoenix, AZ


Bob Hummel founded a company distributing to veterinarians in California, and later joined Jim Loughlin in purchasing RX Company. They incorporated the new combined company under the name Great Plains Chemical Company, Inc.


Dan and Cassy Kane established Kane Veterinary Supplies


Willard Wall brought 9 companies together to form Walco International Bob Hummel moved Great Plains Chemical Company, Inc. to Greeley, Colorado

late 1970’s

Bob Hummel acquired several regional distributors, and began marketing private labels under the name Lextron, Inc.


Charles Nakamura, Eric Johnson and Carl Izumi founded Hawaii Mega-Cor


Great Plains Chemical Company officially changed its name to Lextron, Inc.


Walco International includes 700 employees, and more than $330 million in sales


Turnkey Computer Systems, LLC (Amarillo, Texas) became a wholly owned subsidiary of Animal Health International


In October, Hawaii Mega-Cor joined Animal Health International


Walco International went public under the new name Animal Health International, Inc. In October, Kane Veterinary Supplies Ltd. (Edmonton, Alberta and Cambridge, Ontario) joined Animal Health International


Lextron, Inc. purchased its respected long-time rival Walco International and began operating under the name Animal Health International, Inc.


Patterson Companies purchased Animal Health International.

Animal Health International is the premier animal health distributor

Today, we’re continuing to focus on innovation by investing in our people, technology – software and agricultural tech – and showing dedication to our customers in the animal health industry. 

Our brands 

Aspen Veterinary Resources

Aspen’s innovative products – for veterinary and production teams – are formulated to optimize animal health. 

First Companion

First Companion products enrich the lives of dogs, cats, horses and their owners through protection, treatment and prevention. 

For Veterinarians: Large Animal and Mixed Practice

Whether you’re in a veterinary clinic, production facility or in the field, we can service your business with a full range of products, equipment, technology and services for livestock, equine and companion animals. 

Shop products

For Commercial Producers

Turnkey Computer Systems, LLC – the premier provider of accounting and management systems for the commercial cattle feeding industry – is a wholly-owned subsidiary of AHI. Together, AHI and Turnkey offer the most extensive concentration of expertise, product development, customer service, application support, and research and development in the industry 

Learn more about Turnkey Computer Systems

Animal Health International locations

Guided by our core values

We support the National Future Farmers of America (FFA) with scholarships for young students who want to pursue a career in an agriculture field. We give locally through local FFA branches and 4-H clubs. 

The Patterson Foundation     awards grants to non-profit organizations in the animal health fields.