Biomaterial Database

Inheritance of litter size and its components in crosses between the D'man and Sardi breeds of sheep. 1991

I Boujenane, and G E Bradford, and T R Famula

Hassan II Agronomy and Veterinary Institute, Morocco.

Data on ovulation rate, litter size and embryo survival of 364 Sardi (S), D'man (D), S x DS, DS x S, S x D, D X S (F1), F2, D x DS and DS x D ewes mated for first and second lambing to F1 rams were analyzed. Breed group, birth group and season had significant effects on ovulation rate and litter size but not on embryo survival. D'man ewes had the highest ovulation rate (2.79) and litter size (2.00), with an essentially linear increase in each of these variables with percentage of D'man inheritance in the ewe (b = .017 +/- .001 CL and .009 +/- .001 lambs born). Embryo survival was influenced only by the number of ova shed. D'man direct genetic effects were higher (P less than .01) than those of Sardi for ovulation rate (+1.78) and litter size (+1.08) but did not differ for embryo survival (-.07). Maternal effects differed little for any of the three traits. Individual heterosis estimates were negative and significant for ovulation rate but not significant for litter size and embryo survival. Maternal heterosis and epistatic recombination effects were small and not significant for any trait.

UI	MeSH Term	Description	Entries
D008098	Litter Size	The number of offspring produced at one birth by a viviparous animal.	Litter Sizes,Size, Litter,Sizes, Litter
D008297	Male		Males
D010060	Ovulation	The discharge of an OVUM from a rupturing follicle in the OVARY.	Ovulations
D001947	Breeding	The production of offspring by selective mating or HYBRIDIZATION, GENETIC in animals or plants.	Breedings
D003433	Crosses, Genetic	Deliberate breeding of two different individuals that results in offspring that carry part of the genetic material of each parent. The parent organisms must be genetically compatible and may be from different varieties or closely related species.	Cross, Genetic,Genetic Cross,Genetic Crosses
D005260	Female		Females
D006823	Hybrid Vigor	The adaptive superiority of the heterozygous GENOTYPE with respect to one or more characters in comparison with the corresponding HOMOZYGOTE.	Heterosis,Vigor, Hybrid
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012756	Sheep	Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.	Ovis,Sheep, Dall,Dall Sheep,Ovis dalli
D016018	Least-Squares Analysis	A principle of estimation in which the estimates of a set of parameters in a statistical model are those quantities minimizing the sum of squared differences between the observed values of a dependent variable and the values predicted by the model.	Rietveld Refinement,Analysis, Least-Squares,Least Squares,Analyses, Least-Squares,Analysis, Least Squares,Least Squares Analysis,Least-Squares Analyses,Refinement, Rietveld