scholarly journals GENETIC GAIN OF MILK PRODUCTION IN EGYPTIAN BUFFALO AS AFFECTED BY POPULATION SIZE, NUCLEUS SIZE AND SELECTION INTENSITY IN OPEN NUCLEUS BREEDING SCHEME

2004 ◽  
Vol 41 (1) ◽  
pp. 33-42
Keyword(s):  
Population Size ◽  
Milk Production ◽  
Genetic Gain ◽  
Selection Intensity ◽  
Nucleus Size ◽  
Breeding Scheme ◽  
Nucleus Breeding ◽  
Egyptian Buffalo ◽  
Open Nucleus

Genetic gain in open nucleus breeding scheme to improve milk production in Egyptian Buffalo

2010 ◽  
Vol 131 (2-3) ◽  
pp. 162-167 ◽  
Author(s):  
S.A. Abdel-Salam ◽  
A.I. Sayed ◽  
Manal Elsayed ◽  
S. Abou-Bakr
Keyword(s):  
Milk Production ◽  
Genetic Gain ◽  
Breeding Scheme ◽  
Nucleus Breeding ◽  
Egyptian Buffalo ◽  
Open Nucleus

Open nucleus breeding systems

1977 ◽  
Vol 24 (3) ◽  
pp. 287-305 ◽  
Author(s):  
J. W. James
Keyword(s):  
Numerical Analysis ◽  
Genetic Gain ◽  
Breeding Systems ◽  
Generation Model ◽  
Selection Intensity ◽  
Base Population ◽  
Cattle Breeding ◽  
Discrete Generation ◽  
Nucleus Breeding ◽  
Open Nucleus

SUMMARYA theoretical analysis of open nucleus breeding systems, in which there is some introduction of breeding females to the sire breeding nucleus, is presented. Numerical analysis of a discrete generation model shows that the rate of genetic gain may be increased by 10 to 15% by opening the nucleus when selection intensity in females is low. In sheep and beef cattle breeding the optimal structure would be to have about 10% of the population in the nucleus, to get half of the nucleus female replacements from the base population, and to use all nucleus-born females not needed as nucleus replacements for breeding in the base population. The genetic gain, however, is not very sensitive to variation in these parameters. The rate of inbreeding in such an open nucleus would be about half that in a closed nucleus of the same size.

A simulation study of open nucleus and closed nucleus breeding systems in a sheep population

1995 ◽  
Vol 60 (1) ◽  
pp. 117-124 ◽  
Author(s):  
J. A. Roden
Keyword(s):  
Genetic Gain ◽  
Live Weight ◽  
Breeding Systems ◽  
Breeding Value ◽  
Linear Unbiased Prediction ◽  
Sheep Population ◽  
Best Linear Unbiased ◽  
Nucleus Breeding ◽  
Open Nucleus ◽  
Selection Of

AbstractStochastic simulation was used to compare the results of alternative breeding systems in a sheep population divided into 10 flocks of 120 ewes. The breeding systems compared were selection within closed flocks (CF), a closed nucleus system (CNS), an open nucleus system (ONS) and open nucleus systems with the selection of nucleus replacements being restricted to either nucleus born males (ONSRm) or nucleus born females (ONSRf). Selection was for a best linear unbiased prediction of breeding value for lamb live weight which had a heritability of 0·17. The open nucleus breeding systems (ONS, ONSRm, ONSRf) resulted in higher rates of genetic gain, more predictable selection responses and lower rates of inbreeding than either the closed nucleus system (CNS) or selection within closed flocks (CF). Initial genetic differences between flocks resulted in higher rates of genetic gain in the nucleus breeding systems due to the use of between flock genetic variance. In the ONS system up to 25% of nucleus sires and approximately 50% of nucleus dams were born in base flocks. Nevertheless if selection of either nucleus sires or dams was restricted to nucleus born animals there was very little change in genetic gain or rate of inbreeding.

Assessment of institutional capacities of the Gambia Indigenous Livestock Multipliers’ Associations

2015 ◽  
Vol 57 ◽  
pp. 119-126 ◽  
Author(s):  
O. F. Olaniyan ◽  
N. N. Fall-Diop ◽  
B. Faye ◽  
A. Secka ◽  
O.B. Smith ◽  
...  
Keyword(s):  
Capacity Development ◽  
Participatory Planning ◽  
Breeding Scheme ◽  
Group Facilitation ◽  
Roles And Responsibilities ◽  
Institutional Management ◽  
Effective Strategies ◽  
Management Group ◽  
Nucleus Breeding ◽  
Open Nucleus

SummaryThis exploratory study aims to understand and improve the performance of Gambia Indigenous Livestock Multipliers’ Associations (GILMA – Fulladu and Saloum) as a way of enabling them to better respond to the challenges faced in fulfilling their institutional responsibilities. Using participatory institutional diagnosis, the GILMA members and experts were able to examine their associations and to stimulate collective reflection as a means of making the associations more efficient and effective. The findings of this diagnosis showed that functioning of both GILMAs was closely linked to the operations of their technical partners. This resulted to GILMAs which clearly lack defined vision and mission. Main issues to address include capacity development of GILMA's executive committee in terms of institutional management, group facilitation, participatory planning, effective strategies for partnership and ownership. Overall, this study developed pathways for revitalizing GILMAs into vibrant and self-sustaining indigenous ruminant livestock multipliers’ associations that can effectively carry out specific roles and responsibilities within the three-tier Open Nucleus Breeding Scheme of the International Trypanotolerance Centre.

Sign in / Sign up

Export Citation Format

Share Document