University of California

Sustained-release bolus for deworming dairy heifers


Thomas A. Shultz
E. Michael Huffman
Norman F. Baker

Authors Affiliations

Thomas A. Shultz is Dairy Advisor, Cooperative Extension, Tulare County; E. Michael Huffman is a veterinarian in private practice, Visalia-Hanford, California; Norman F. Baker is Professor of Microbiology, School of Veterinary Medicine, University of California, Davis.

Publication Information

Hilgardia 42(2):4-5. DOI:10.3733/ca.v042n02p4. March 1988.

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A major source of gastrointestinal worm infestation of grazing heifers is larvae that have survived the winter on pasture grass. When these larvae are swallowed and mature inside the heifer, they produce eggs that are shed in the feces, resulting in a higher pasture contamination later in the grazing season. To break this recycling of pasture worm infestations, multiple deworming is needed. This adds labor and other costs, since the heifers are on pasture and may not be easily accessible.

Shultz T, Huffman E, Baker N. 1988. Sustained-release bolus for deworming dairy heifers. Hilgardia 42(2):4-5. DOI:10.3733/ca.v042n02p4
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