7 February 1997

SELECTING TOP COWS

SELECTING the top 10,000 cows and heifers from breeders herds each year for selective mating will ensure that the OGER breeding programme in the west and south of France has bull mothers for the future.

The programme – known as the Gentique Avenir Scheme – according to Jean-Alexis Coquer-eau will produce bull mothers in one or two generations.

"The goal is to increase the genetic level of the cow population, both for breeders and the programme," he says.

"We try to find the best sires in the world to mate with these cows." Individual matings are chosen by breeders and co-op technicians for 7500 of these top females. The remaining 2500 matings are chosen by the sire analysts.

The 3500 breeders involved give first choice of young bulls to the programme. In return they receive imported semen at a low price and are allocated more straws from the top OGER-owned bulls.

Within OGER all members receive an allocation of semen from proven sires and pay just one price of £23.50 for each first insemination including semen; repeat inseminations are free. Of this payment £7.60 goes towards the breeding programme.

The key aim of the OGER breeding programme is to improve milk protein output, he says.

"Protein is more difficult to increase so we put our energy into improving it – when selecting cows and sires of sons we look at protein first. But we are also working to improve functional type, quality of udders, feet, legs and body to have strong cows."

OGER puts more emphasis on frame than many other breeding schemes because most cows graze grass or eat hay – whereas in the Netherlands, for example, they feed more concentrate, explains Mr Coquereau.

"Large intakes of forage will help reduce milk production costs," he says.

For progeny testing and bull selection the two AI organisations OGER and MIDATEST work together to sample 160 bulls a year.

Bulls are selected from members herds, the co-ops nucleus open herd and embryos purchased from the US, Canada and Holland.

"Bulls from the nucleus herd have proofs closer to their pedigree index – proving more accurate than imported animals for which we must use converted values," says Mr Coquereau.

"We still have good results with US bulls and our goal is to be open and try to progeny test the best genetics available in the world."

However, he claims that it is hard to find cow families more advanced than in France because the Genetique Avenir programme has been strengthening its female lines for 20 years.

Each year 600 heifers are selected to enter the open nucleus herd. Most of these heifers come from the Genetique Avenir scheme with 120 heifers selected from the 350 embryos that are imported each year.

These animals are used to breed most bulls for the progeny testing scheme – 450 bulls come from the nucleus herd, a further 100 come from first lactation cows in OGER-MIDATEST breeders herds and 50 are purchased from other selected cows.

When the bulls are bought from members herd OGER-MIDATEST have the first option to buy and pay a fixed price a bull.

This avoids creating differentiation in the price and farms are well known so there is little encouragement for breeders to give preferential treatment to bull mothers, claims Mr Coquereau. Preferential treatment is only a concern when selecting bull mothers from breeders herds when their sons have a high value.

From the 600 bulls a year bought only 160 will be progeny tested. This gives a higher selection pressure than other AI organisations, he claims. This is necessary because it is selecting bull mothers in their first lactation. As such the dams potential is not realised until the bull is a year old.

Progeny testing is compulsory for herds that milk record, so there are 560,000 milk recorded cows available for progeny testing in the OGER-MIDATEST area.

Each producer will serve 8.5% of the herd with progeny test semen. These animals are selected by the technicians not the breeders – they will be first lactation heifer but not those that are extremely high or extremely low yielding, he adds. Only using 8.5% of young sires in each herd ensures that bull daughters will have contempories from proven sires.

In addition only one straw of each bull is used in any herd. In this way it is possible to get 80 daughters in 80 herds from just 320 straws of semen. This produces a reliability of above 70% for the bulls first proof – which is the minimum reliability needed for publishing a proof in France.

The control OGER has over the progeny testing and very low use of DIY AI ensures that young bull semen is used quickly. On average the best semen is used in one month.

Jean-Alexis Coquereau is intent on improving the genetic level of the French cow population.


OGER-MIDATEST


&#8226 Producing future bull mothers through Genetique Avenir.

&#8226 High selection pressure for young bulls.

&#8226 All milk recording members must progeny test.