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Ten years ago Semex released the best brand for health selection in dairy cattle genetics and now, we’re releasing the next generation of Immunity+ with August genetic evaluations!


“We’ve taken Immunity and brought it to a whole new level, with a full proof and a unique approach, that makes it hands down the most effective means to make gains in animal health,” says Jay Shannon, Vice President Semex Solutions and Marketing.


Over the past 10 years dairymen worldwide have seen the real advantages of using Immunity+ sires. It is highly heritable, has a huge economic impact, provides for higher quality colostrum and daughters are shown to have 29% less disease.


Now, all Semex sires will receive an index for Immunity and Calf Immunity, making it even easier to make health selection. The ‘next generation’ of Immunity+ optimally combines Immune Response (Antibody Mediated Immune Response, Cell Mediated Immune Response and Nitric Oxide), as well as a composite of publicly available disease traits sourced from CDCB, Lactanet and Zoetis. This ensures resulting animals can both mount a strong overall immune response, but also be able to recognize the specific pathogens that cause the costliest diseases on dairies.


The index has a mean of 100, and a standard deviation of 5, with proofs generally ranging from 85-115. Immunity+ bulls will be designated as being superior transmitters of high immune response if they have an Immunity Index >= 105 and a Calf Immunity Index >= 100. Additionally, dairymen taking advantage of Semex’s Elevate® genomic testing program will receive two indexes on all tested females, Immunity Index and Calf Immunity Index. These replace the former H(high)-A(average)-L(low) letter codes that were published on tested females.


For additional information on Immunity+ and Semex please visit