J. Anim. Breed. Genet. ISSN 0931-2668
ORIGINAL ARTICLE
Implementation of genetic evaluation and mating designs for the endangered local pig breed ‘Bunte Bentheimer’ € nig1 A.D.M. Biermann1, E.C.G. Pimentel1, M. Tietze1,2, T. Pinent1 & S. Ko 1 Department of Animal Breeding, University of Kassel, Witzenhausen, Germany €ttingen, Go €ttingen, Germany 2 Animal Breeding and Genetics Group, Department of Animal Sciences, Georg-August-University of Go
Keywords Endangered pig breed; fertility; inbreeding; optimal genetic contributions. Correspondence A. Biermann, Department of Animal Breeding, University of Kassel, Nordbahnhofstraße 1a, 37213 Witzenhausen, Germany. Tel: +49 (0) 5542 981597; Fax: +49 (0) 5542 981589; E-mail: [email protected] Received: 12 October 2012; accepted: 15 April 2013
Summary A pedigree including 1538 individuals of the endangered pig breed ‘Bunte Bentheimer’ and 3008 records of the fertility traits ‘number of piglets born alive’ (NBA) and ‘number of piglets weaned’ (NW) were used to i) characterize the population structure, ii) to estimate genetic (co)variance components and estimated breeding values (EBVs) and iii) to use EBVs for the application of the concept of optimal genetic contributions. The average coefficient of inbreeding increased from F = 0.103 to F = 0.121 within the two recent cohorts. Average rate of inbreeding amounted to 1.66%, which resulted in an effective population size of Ne = 30 animals in the recent cohort. Average generation interval was 3.07 years considering the whole pedigree, and in total, only 612 sows and boars generated offspring. Estimated heritabilities for both traits NBA and NW were 0.12, and the estimated genetic correlation between both traits was 0.96. The variance component due to the service sire was higher than in commercial pig breeds, presumably due to the widespread use of natural service boars. The EBVs for NBA from 333 selection candidates (63 boars and 270 sows) were used to determine optimal genetic contributions. Based on selected animals and their optimal genetic contributions, specific mating designs were evaluated to minimize inbreeding in the next generation. Best results were achieved when using a simulated annealing algorithm and allowing artificial insemination.
Introduction The local origin of the pig breed ‘Bunte Bentheimer’ (BB) is the polder region in north-western Germany. An extended overview of breeding activities which started in the middle of the 19th century is given by Kolk gen. Sundag (2006). In brief, an F1-cross of local Landrace sows with Berkshire boars from the UK was established in 1900 as a synthetic line, and only a limited percentage of migration from Cornwall boars from the UK, and Poland China boars from the US, was allowed. Furthermore, some gene flow from Tamworth pigs at the end of the 19th century is assumed. Official herd book registration of the BB started in 1950. However, population size of the BB doi:10.1111/jbg.12041
breed substantially decreased from the middle to the end of the 20th century due to the importance of lean meat percentage, which restricted the use of fatty pig breeds. In the past three decades, population size included
ORIGINAL ARTICLE
Implementation of genetic evaluation and mating designs for the endangered local pig breed ‘Bunte Bentheimer’ € nig1 A.D.M. Biermann1, E.C.G. Pimentel1, M. Tietze1,2, T. Pinent1 & S. Ko 1 Department of Animal Breeding, University of Kassel, Witzenhausen, Germany €ttingen, Go €ttingen, Germany 2 Animal Breeding and Genetics Group, Department of Animal Sciences, Georg-August-University of Go
Keywords Endangered pig breed; fertility; inbreeding; optimal genetic contributions. Correspondence A. Biermann, Department of Animal Breeding, University of Kassel, Nordbahnhofstraße 1a, 37213 Witzenhausen, Germany. Tel: +49 (0) 5542 981597; Fax: +49 (0) 5542 981589; E-mail: [email protected] Received: 12 October 2012; accepted: 15 April 2013
Summary A pedigree including 1538 individuals of the endangered pig breed ‘Bunte Bentheimer’ and 3008 records of the fertility traits ‘number of piglets born alive’ (NBA) and ‘number of piglets weaned’ (NW) were used to i) characterize the population structure, ii) to estimate genetic (co)variance components and estimated breeding values (EBVs) and iii) to use EBVs for the application of the concept of optimal genetic contributions. The average coefficient of inbreeding increased from F = 0.103 to F = 0.121 within the two recent cohorts. Average rate of inbreeding amounted to 1.66%, which resulted in an effective population size of Ne = 30 animals in the recent cohort. Average generation interval was 3.07 years considering the whole pedigree, and in total, only 612 sows and boars generated offspring. Estimated heritabilities for both traits NBA and NW were 0.12, and the estimated genetic correlation between both traits was 0.96. The variance component due to the service sire was higher than in commercial pig breeds, presumably due to the widespread use of natural service boars. The EBVs for NBA from 333 selection candidates (63 boars and 270 sows) were used to determine optimal genetic contributions. Based on selected animals and their optimal genetic contributions, specific mating designs were evaluated to minimize inbreeding in the next generation. Best results were achieved when using a simulated annealing algorithm and allowing artificial insemination.
Introduction The local origin of the pig breed ‘Bunte Bentheimer’ (BB) is the polder region in north-western Germany. An extended overview of breeding activities which started in the middle of the 19th century is given by Kolk gen. Sundag (2006). In brief, an F1-cross of local Landrace sows with Berkshire boars from the UK was established in 1900 as a synthetic line, and only a limited percentage of migration from Cornwall boars from the UK, and Poland China boars from the US, was allowed. Furthermore, some gene flow from Tamworth pigs at the end of the 19th century is assumed. Official herd book registration of the BB started in 1950. However, population size of the BB doi:10.1111/jbg.12041
breed substantially decreased from the middle to the end of the 20th century due to the importance of lean meat percentage, which restricted the use of fatty pig breeds. In the past three decades, population size included
