Application of DNA paternity tests to evaluate bull prolificacy in Multi-Sire Cattle Herds and the Differences in their Offspring Performance Lead Scientist – Dr. Obioha Durunna
Duration – 2019 to 2023
Background Herd bulls have significant impacts on beef productivity and profitability. Multiple bulls can be used to increase reproductive rates, especially when artificial insemination is not practical due to cost or infrastructure limitations. Beef producers implementing natural mating schemes prefer bulls with the genetic potential for production, desirable carcass traits, and improved reproductive efficiencies. Bull prolificacy under multi-sire breeding groups is required to ensure the efficient use of feed and other farm resources. Because it is difficult to predict the number of calves each bull in a multi-bull herd will sire, identifying the calves sired by each bull can be achieved through DNA paternity testing. DNA paternity testing allows for potential sires to be linked to potential calves using commercial genetic marker panels. The information on bull prolificacy enables owners to make informed culling and purchasing decisions based on their performances, especially on the bulls that did not meet expectations. These sire-progeny matches also support accurate pedigree information and record-keeping that enhance selection, breeding, and management decisions. Commercial herds in Alberta typically run multiple bulls with their cows and replacement heifers. Knowing the average prolificacy of bulls can help producers understand their bulls’ current and future contributions to productivity, profitability and sustainability. This information will also create helpful industry benchmarks that will guide producers in decision-making.
Objectives This project demonstrated how commercial beef producers who typically operate multi-sire breeding programs can: • use a handy tool (e.g., Q-Link) to collect tissue/DNA used in determining sire-progeny matches • implement or improve record-keeping • track offspring data to make informed breeding decisions. This project aims to equip producers with practical information and methods that will demonstrate the use of paternity testing tools to assess sire prolificacy in multi-sire breeding pastures
Materials and Methods