Spanish research shows the way to optimum milk production

Wednesday, August 10, 2011

Catalonia's Institute for Research & Technology in Agriculture & Food (IRTA) has some of the best facilities in Europe for testing cow performance. Results from thousands of milkers can help producers develop the most efficient feeding regime for their herds

by NORMAN DUNN
 

Prof. Alex Bach must have one of the biggest outdoor testing facilities in the world. This dairy expert with the Catalonian IRTA organization works closely with the French/Spanish La Pirenaica dairy farmer co-operative.

The group includes around 100 herds on virtually the same feed. The cows are also bred with the same Canadian Holstein bulls. Almost without exception, the housing features cubicles with bunk feeding of silage. A total mixed ration is centrally mixed and delivered daily to the farms. The veterinary team is shared by all. Even the corn silage is chopped and clamped for the individual herds by the same team of contractors.

"These conditions are almost unique. They give us a tremendous base for testing influences on milk production under absolutely practical conditions," enthuses Bach.

An excellent example of how such a facility can very quickly lay bare the bones of dairying practice is offered by the latest work under these conditions.

Bach and his team set out to find the main non-nutritional influences on yield in modern dairies. Aided by the almost identical rations on offer and the very similar genetic makeup, these were relatively rapidly identified as age at first calving, silage feeding technique at the feed bunk and, finally, the availability of cubicles for milking herd members.

To make the research more manageable, the IRTA team selected a smaller pool of dairy herds to work with. Within a radius of 59 kilometres, 47 herds were selected. These involved a total of 3,129 milking cows in herds that ranged from just 23 cows to one with 232 head. To set up the right conditions for comparing non-nutritional influences, milk production was recorded daily. So was feed on offer and dry matter intake.

"We found fairly early on that the optimum time for first calving is 22 months with the heifer weighing around 700 kilograms. In the herds of La Pirenaica, this figure was missed by a long way. First calving date averaged 27.7 months," he recalls.

Comparing performances with heifers calving at earlier dates showed that daily milk yield for those calving at 25 months or earlier ran from around 30 to 32.5 kilograms, while later calvers averaged as much as 2.5 kilograms less milk daily. But there was more: Bach found that heifers calving after 24 months were more likely to be slaughtered before the end of that first lactation. 

Incidentally, the first calving dates for European dairy herds in this context show there's a fair bit of improvement needed there, too, with national averages running from 24 months right through to 29.

A real surprise was the outcome that feeding bunk space per cow didn't seem to influence yield. The average for all the 47 farms involved was a generous 69 centimetres. But Bach points out that 20 per cent of the herds actually allowed less than 50 centimetres feeding space per cow and performance wasn't affected.

What really made a difference was pushing feed towards the cows. Those herds where this practice was followed averaged around four kilograms of milk per cow and day more. But it didn't seem to matter how many times per day the feed was pushed up. Just once per feeding seems to be enough in Spain. 

A major non-feed factor affecting yield in the Spanish investigation, after date of first calving, turned out to be availability of cubicles. In herds with just 0.6 cubicles per cow, milk yield average was around 25 kilograms a day during the investigation. Those offering a generous 1.4 cubicles per cow returned an average yield closer to 30 kilograms.

"Most of the cows' time is spent lying in the cubicles," explains Bach. "So if there's any constraint on this, it shows in performance." Also, the long-term recording on these dairy farms showed a strong relationship between availability of cubicles and proportion of cows culled.

The bottom line from this Spanish research is that it can now be reasonably simple to maintain a very efficient feeding regime for optimum milk production, but that all the other production factors need to be looked at more closely. After all, the Spanish research concluded that the non-nutritional influences were responsible for up to 13 kilograms less milk per cow and day in some herds. BF

Norman Dunn writes about European agriculture from Germany.