Abstract
BackgroundControlled mating procedures are widely accepted as a key aspect of successful breeding in almost all animal species. In honeybees, however, controlled mating is hard to achieve. Therefore, there have been several attempts to breed honeybees using free-mated queens. In such breeding schemes, selection occurs only on the maternal path since the drone sires are random samples of the population. The success rates of breeding approaches without controlled mating have so far not been investigated on a theoretical or simulation-based level.MethodsStochastic simulation studies were carried out to examine the chances of success in honeybee breeding with and without controlled mating. We investigated the influence of different sizes of breeding populations (500, 1000, 2000 colonies per year) and unselected passive populations (0, 500, 1000, 2000, infinitely many colonies per year) on selection for a maternally (queen) and directly (worker group) influenced trait with moderate (r_{md}=-,0.53) or strong (r_{md}=-,0.88) negative correlation between the two effects. The simulations described 20 years of selection.ResultsOur simulations showed a reduction of breeding success between 47 and 99% if mating was not controlled. In the most drastic cases, practically no genetic gain could be generated without controlled mating. We observed that in the trade-off between selection for direct or maternal effects, the absence of mating control leads to a shift in favor of maternal effects. Moreover, we describe the implications of different breeding strategies on the unselected passive population that benefits only indirectly via the transfer of queens or drones from the breeding population. We show that genetic gain in the passive population develops parallel to that of the breeding population. However, we found a genetic lag that became significantly smaller as more breeding queens served as dams of queens in the passive population.ConclusionsWe conclude that even when unwanted admixture of subspecies can be excluded in natural matings, controlled mating is imperative for successful breeding efforts. This is especially highlighted by the strong positive impact that controlled mating in the breeding population has on the unselected passive population.
Highlights
Controlled mating procedures are widely accepted as a key aspect of successful breeding in almost all animal species
Breeding queens (BQ) were queens whose colonies underwent performance tests and that were subject to selection
Drone producing queens (DPQ) were queens that produced the drones with which BQ could mate on a mating station
Summary
Controlled mating procedures are widely accepted as a key aspect of successful breeding in almost all animal species. In honeybees controlled mating is hard to achieve. There have been several attempts to breed honeybees using free-mated queens. In such breeding schemes, selection occurs only on the maternal path since the drone sires are random samples of the population. Sir Bakewell combined strict record-keeping with the intentional mating of closely related animals for the expression of desirable traits in the population. His breeding strategies proved successful and were soon copied across. Species for which controlled mating is hard to achieve, such as aquaculture species, lag behind in breeding success partly for this reason [4, 5]. Modern breeding strategies, involving genetic evaluation, rely heavily on reliable
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.