Loading...
Please wait, while we are loading the content...
Similar Documents
Schätzung von Kreuzungsparametern unter besonderer Berücksichtigung von epistatischen Effekten und einer Optimierung des Kreuzungszuchtverfahrens beim Meerschweinchen in Bolivien
| Content Provider | Semantic Scholar |
|---|---|
| Author | Zumbach, Birgit |
| Copyright Year | 1998 |
| Abstract | Estimation of Crossbreeding Parameters with Special Consideration of Epistatic Effects and Optimisation of Crossbreeding Procedures For Guinea Pigs in Bolivia The present study investigates the guinea pig as a native animal for meat production in the Andean countries of Latin America. In the framework of rural development the guinea pig can contribute to a better meat supply and a source of income especially for small holders by improving breeding and management. The objective of this study is to estimate crossbreeding parameters, focusing on epistatic effects, from crossings between a small framed synthetic native line consisting of 29 Bolivian strains and an imported line from Peru selected for body weight, kept under semi-intensive/semi-extensive „modern“ management conditions. Conclusions for the optimisation of breeding systems should also be derivated.. In the introduction first the special biological charcteristics as well as the cultural and symbolic meaning of the guinea pig, and management systems, are briefly described. The literature part treats gene effects in crossbreeding, especially non-additive gene effects, as well as the planning and optimization of crossbreeding systems. Also a literature review of the guinea pig reproduction and production performance in pureand crossbreeding is presented. In the present study, data from 2857 first and second litters and 7745 progenies, stemming from the matings of 391 bucks with 1688 dams were analysed. The animals belong to a native synthetic Bolivian line, developed at the Universidad Mayor de San Simon, Cochabamba, Bolivia, and an imported Peruvian line as well as to 12 crossbreeding groups derived from these stocks: reciprocal F1s, reciprocal backcrosses, F2, pre-rotational groups and a synthetic line with 50% gene proportion of each purebred line. The basic model for the estimation of crossbreeding parameters is the Jakubec model with three different kinds of epistatic effects (additive x additive interactions, additive x dominance interactions, dominance x dominance interactions) and the Dickerson model with the recombination loss as epistatic effect on the individual (progeny), maternal (individual), paternal (male mating partner) and grandmaternal (maternal) level. Because of the intercorrelation of parameters (multicolinearity) and with the objective to estimate the most relevant parameters for practical breeding methods and strategies the number of parameters per genetic model was restricted to five with one epistatic effect, respectively: Dickerson-Modell: gi, hi, ri, gm, hm and gpr, hpr, rpr, gi, hi; Jakubec-Modell aa: gi, di, aai, gm, dm and gpr, dpr, aapr, gi, di; JakubecModell dd: gi, di, ddi, gm, dm and gpr, dpr, ddpr, gi, di (i: individual, m: maternal, pr: progeny). The synthetic native Bolivian line was considered as reference. GLSand LS-breeding group means and crossbreeding parameters were estimated for body weight and growth traits, reproduction traits and productivity traits. The prevailing crossbreeding effects are line differences with positive signs for production traits and with negative signs for the number of progeny per dam and per metabolic dam weight in the first half year of production. The genetic models and the results are discussed in a global context and recommendations are derived for breeding systems and selection for the investigated lines under the specific seasonal and economical conditions prevailing at Cochabamba, Bolivia. |
| File Format | PDF HTM / HTML |
| DOI | 10.18452/14311 |
| Alternate Webpage(s) | https://edoc.hu-berlin.de/bitstream/handle/18452/14963/Zumbach.pdf?isAllowed=y&sequence=1 |
| Alternate Webpage(s) | http://edoc.hu-berlin.de/dissertationen/agrar/zumbach-birgit/PDF/Zumbach.pdf |
| Alternate Webpage(s) | https://doi.org/10.18452/14311 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
