Servizio Comunitario di Informazione in materia di Ricerca e Sviluppo - CORDIS

Health of dairy cows milked by an automatic milking system

In Denmark, the Netherlands, and the UK, 15 herds each were recruited for monitoring the impact of transition to automated milking on animal health. The herds recruited represented the types of AMS marketed in each country. Each farm was visited at least twice before installation of the AMS and a minimum of twice, but often up to six times, after installation. On these visits assessments were made of at least half of the cows or fifty animals on body condition and locomotion, and forty cows for teat condition (on some farms in the Netherlands and UK only). Farm data including milk production, milk quality, animal records on individual cow cell count, fertility, animal treatments, animal movements, veterinary purchases etc. Additionally data were collected on all other infections, diseases and conditions likely to affect milk quality, production, and attendance at the automated milking system and involve special staff time.

The body conditions varied more between countries than in response to the introduction of AM. In Denmark and the UK there was no change in body condition between 3-6 months prior to AM installation and 6 months post installation. A slight but not significant drop occurred with the Dutch cows. On the Dutch farms the range of body condition narrowed significantly from 1.35 to 0.98 points score suggesting that the farms are managing body condition, probably feeding, better. However, most of the change was due to the farm with the thinnest cows increasing condition by three quarters of a point. In the UK the range increased mostly because the thinnest cows became thinner and the fattest cows became fatter suggesting an exacerbation of the lack of adequate feeding management on two of the poorer units.

No change in locomotion had occurred by one month after AM installation. The scores had increased slightly, but not a significant difference, in both countries by 3months after AM installation. The ranges also increased and the average score increased on seven farms whilst unchanged on 6 farms in the UK. Scoring was continued on 12 of the UK farms. Twelve months after installation of AMS the lameness has increased significantly. Prior to installation eleven of fourteen UK herds were grazed but only six after installation. The poorer locomotion may reflect the increase in constant housing.

The overall impact of conversion to AM may be assessed by comparing how each individual farm has coped in terms of the main indicators of animal health related to the changes in production methods. This has been attempted for the Dutch and the UK data. Comparing 12 Dutch farms only one improved in locomotion, body condition as well as cell counts. This farm had a significant improvement in locomotion score from a poor pre-installation standard. It was one of only two farms that reduced the cell count and the proportion of cows with a high cell count. However, the cows were already some of the thinnest in the study and became thinner so body condition may not truly have improved. Overall, little change was apparent. Locomotion improved in five herds and deteriorated in five herds. Body condition score decreased in eight herds but only by a small amount. It increased in two herds but not making the cows any fatter, just more typical. The only major deterioration was in average milk cell count and the proportion of cows with a cell count above a threshold, where only two of the herds produced better quality milk. Average milk yield in the Dutch herds decreased in continuation of a trend starting up to 12-months prior to installation of the AMS and the cows became thinner with only a small reduction in DIM.

Data on herd fertility are only available, so far, from the UK and then only from 6 herds. Overall there is little evidence of major changes occurring in the common measures of fertility. None of the changes were statistically significant but all suggestive of poorer fertility, at least in the transition period from conventional milking to AM.

No major problems in converting from conventional milking to AM have been identified but equally none of the 44 farms has been found to achieve a substantial improvement in any aspect of cow health. Given that most of the farms studied were confronted by many and varied problems in conversion, with no clear advice readily available, they have all achieved a remarkable success. The transition period to AMS comprises a period of higher risk to health that extends from weeks before installation when resources start to be diverted from cow management. The length of the transition will vary on individual farms related to many unique factors. Several potential problems may develop in the longer term and anticipation of these is necessary. Clearly AMS succeeds but its longer-term promises for animal welfare and milk quality are unfulfilled to date.

Informazioni correlate


Eric HILLERTON, (Senior scientist)
Tel.: +44-1635-577248
Fax: +44-1645-577286