I coordinate the international rumenpangenome program run from UWA - the focus of the work is the hosts control on rumen processes as well as understanding genetic control - please contact if you require more info - thanks Julian 

Thank you for this important subject , because the local animal resources began to disappear gradually due to its poor performance compare with selected animals or the commercial genotypes, but we know that these genetic resources may be need by humanity in the future because of appearance of new demands .

Although , there were many programs to conserve genetic resources , but these efforts not enough to stop the lose of these resources . We need to adopt new culture represent these resources very valuable and must remain to needs of next human generations .

Economic importance of unimproved or native animals for whom? Farmers or as a national worth for a nation? Economic values are required for cost-benefit analysis, when we talk with farmers. Everybody knows improved animals are better than native ones in growth and production traits. So, I debt that a farmer rears native animals because of their importance as a genetic resource.  I think that when a breed is in danger, the government should pay the tax, so neither economic value nor cost-benefit analyses are needed or even logical?  

Strategies about added values for animal genetic resources which is a promising way to promote local animal population:

Cross-breeding for enhanced

production

RATIONALE

The potential of cross-breeding

The use of cross-breeding as part of a conservation effort may seem counterintuitive, but it

can be a valuable option in certain situations. The concept of using limited cross-breeding

for genetic rescue of an extremely endangered population with a small

Neis introduced in Box 38. There are, however, other instances where cross-breeding may play a role in a conservation programme. Cross-breeding can be particularly useful when the objective of the conservation programme is to use the beneficial genes of a breed at risk without having to obtain high economic returns from the pure-bred population.

Cross-breeding provides the opportunity to combine the genetic characteristics of different breeds. Its use is recommended when there are multiple breeding-goal traits that

have antagonistic genetic relationships, such as those between production and fertility or

between the quantity produced and the quality of the product. It can be difficult to improve

such traits simultaneously in a single breed. This may, for example, mean that combining

the adaptive traits of a locally adapted breed with the production traits of an introduced

international transboundary breed is an attractive option. However, cross-breeding is only

effective and sustainable if the breeding system is carefully chosen and well planned. The

breeds used need to be available over the long term and the cross-breeding plans need

to be strictly followed by the participating livestock keepers. A section in the guidelines

Breeding strategies for sustainable management of animal genetic resources

(FAO, 2010) is devoted to cross-breeding.

Cross-breeding strategies

One simple strategy for maintaining locally adapted animal genetic resources is to cross-

breed the non-recorded and low-producing surplus locally adapted females, while main

-taining pure-breeding (and within-breed selection) among the best animals of the locally

adapted breeds. This limited and targeted cross-breeding not only saves the locally adapted

breeds while improving them genetically, but also maximizes the contribution of the lower-

producing animals to local commodity production and food security. Breeds that have been characterized for production potential and determined to be economically sustainable as a pure-breed should be managed through breeding systems that aim to enhance their productivity. Female animals belonging to these breeds should generally not be used for cross-breeding. These breeds should instead be improved through within-breed selection. Breeds that have been characterized as low producing, or those that are already crosses of various locally adapted breeds, are logical candidates to have their production improved by using genetically superior germplasm either from well-defined improved breeds from the local area or introduced breeds that are relevant for the local production systems. The decision to cross-breed should then be based on economic factors (costs versus expected returns) and the extent of interest and agreement on the part of the local livestock keepers.

Unregulated and unmonitored cross-breeding can rapidly erode the numbers and

genetic integrity of any breed that is used widely for cross-breeding. The utility of many

breeds comes specifically from their role in organized cross-breeding systems, so attention

must be given to maintaining a sufficiently large and well-managed pure-bred population

to ensure the continued availability of animals for the cross-breeding system.

When a breed is being used in a cross-breeding programme, specific information should

be collected during breed surveys and characterization studies. Useful information about

the breed’s role in cross-breeding includes its population size and the current proportion of

pure-bred as opposed to cross-bred breeding. Recording the number of females mated pure quickly captures this aspect of the breed’s dynamics. The data collected should also include the ultimate fate of cross-bred and pure-bred offspring, and whether these are terminal (i.e. marketed without producing offspring) or used for further reproduction. Assessments should include the relative quality (high, medium, low) of the animals used in pure-breeding and those used in cross-breeding. It is important to describe the role of each sex in the cross-breeding production system (e.g. are males used for cross-breeding with other breeds or are females used in this role?). Ideally, pure-bred populations will be undergoing selec-tion for enhanced performance as measured in both pure-bred and cross-bred offspring

.

Implementing cross-breeding systems

The planning and implementation of a cross-breeding programme should be based upon a

clear understanding of what is wanted as an outcome of the programme. If the objective is

to increase production in a locally adapted breed, cross-breeding with an introduced breed

may be considered. A fairly common and simple approach used to improve production is

to cross a locally adapted breed with a high-output international transboundary breed. This

can be done with one of three goals in mind:

1.replacing the local genetics, i.e. by making continual successive crosses to the intro

-duced breed;

2.upgrading the locally adapted breed, i.e. by crossing to the introduced breed until

the population contains a high proportion (usually >50 percent) of introduced-breed

genetics; or

3.maintaining the locally adapted breed as a pure-breed, but using cross-breeding to

produce a population of commercial animals that are used for production, but not for

breeding.

The replacement strategy is clearly not conservation and frequently fails in tropical or

other environmentally stressful regions because the resulting animals are less well adapted

to the local conditions than the original population was. Thus, before embarking on a strat

-egy that will lead to the elimination of local animal genetic resources through replacement

breeding, the consequences of such a strategy must be thoroughly investigated.

Thank you with you rmsg, I agree with the economic consideration and cross breeding strategies suggested.

Please, check my presentation ad the EAAP 2010 of Crete, as potential strategies to use:

http://www.eaap.org/Previous_Annual_Meetings/2010Crete/Papers/14_Cassandro.pdf

let me know your opinions and integration to this vision

best regards to all

Martino

Genetic diversity measured by the number of alleles that exist for any loci is a bit different from the concept of breeds or crossbreeds or hybrids. We really need to retain as many of the existing alleles as possible, but this does not have to be done by maintaining any specific breed. Genomic testing or mapping is the best way to identify the unique alleles and those need to be incorporated into populations of sufficient size that they can be maintained, either as live animals or as frozen semen or embryos. One cannot really know much about genetic diversity today without looking at DNA sequences within a breed or type of cattle. Genomic analyses is what is needed to ensure as much diversity as is feasible.

Dear Jack

The risk now at population level , to be exist or disappear , especially the local breeds which have lower genetic merits for economic productive traits , these populations at risk of extinction .

If we go to gene level , we may work against the natural selection , where the good gene to become widespread due to his fitness , and the bad allele discard by natural selection due to low viability or fertility , so if we do artificial selection against natural selection the natural selection will win in the long term , because the environmental conditions have continuous changes and they force the genotypes to have correlated changes .

Best Regards