Document Type
Thesis - Open Access
Award Date
2024
Degree Name
Master of Science (MS)
Department / School
Animal Science
First Advisor
Michael Gonda
Abstract
The Afrikaner breed of cattle is indigenous to South Africa and due to their hardiness was once the most popular breed amongst farmers. The objectives for this study were to: (1) estimate environmental effects (age at first calving, season) and (2) genetic variance affecting longevity in Afrikaner cattle using survival analysis and a Weibull model and (3) evaluate the effect of the Infusion Project on longevity utilizing a Cox model. For the first objective, age at first calving impacted longevity as younger age at first calving was associated with decreased longevity. Season of birth and year of birth also impacted longevity. For the second objective, longevity in Afrikaner cattle was lowly heritable although sufficient breeding value variation was uncovered to justify selection for this trait. For the third objective, the Infusion Project was developed to target shortcomings of the Afrikaner breed with the introgression of Bonsmara alleles into Afrikaner cattle. The first backcross generation (BC1) and the initial Afrikaner-Bonsmara cross generation (F1) had greater longevity. The second (BC2) backcross generation did not differ in longevity relative to the purebreds (P ≥ 0.05). Infusion of Bonsmara germplasm increased longevity of the hybrid females, in the short-term.
Library of Congress Subject Headings
Africander cattle -- Longevity.
Beef cattle -- South Africa.
Publisher
South Dakota State University
Recommended Citation
Bot Steffl, Allison M., "Longevity in Afrikaner Cattle: A Survival Analysis" (2024). Electronic Theses and Dissertations. 992.
https://openprairie.sdstate.edu/etd2/992