NADIS is a network of 40 veterinary practices and six veterinary colleges monitoring diseases in cattle sheep and pigs in the UK.

NADIS data can highlight potential livestock disease and parasite incidence before they peak, providing a valuable early warning for the month ahead.


NADIS disease forecasts are written specifically for farmers,
to increase awareness of prevalent conditions and promote disease prevention and control,
in order to benefit animal health and welfare.
The forecasts are based on national trends and farmers are advised to discuss
their individual farm circumstances with their veterinary surgeon
.

Metabolic Disease
The number of cases of both acetonaemia and displaced abomasums both increased significantly in January, however in neither case did the increase result in the number of cases being above average.
 
Figure 1: Monthly reports of acetonaemia for May 2005 to Jan 2006 compared to the average for 1997 to 2004. 

table1-nadis

For acetonaemia the increase was from an unusually low level with less than half the average cases being reported in December.

This probably reflects the quality of forage being fed to early lactation cows; it will be interesting to see whether the November/December figures were unusual or whether January was just a blip.

Reports from NADIS vets and the precautionary principle strongly suggest that forage quality is okay but not exceptional.

It is thus likely that the usual early spring rise will occur as normal.

So farmers and vets need to be on the look out for cows which just aren’t performing, particularly if they have lost weight.

Those signs are also typical of the second metabolic disease which increased significantly in January, displaced abomasum (DA).

However numbers in January were way down on the 83 seen in January last year and the peak of 113 in January 2004, in fact they are the lowest since 2002.

Again as with acetonaemia the relatively low incidence may reflect a generally better quality of forage.

Nevertheless the figures are still twice the average of 1997 -2000 so still strongly support the suggestion that there has been a step change in the incidence of DA’s in UK dairy cattle and that we need to pay more attention to controlling and preventing this economically important disease.

Figure 2: Comparison of monthly averages of DA reports for 1997 – 2000 with the averages for 2002 – 2005

table-2-nadis

Fertility

Another factor suggesting that cattle feed intakes this winter have been good up to now is the low level of reports of ovarian cysts.  

Indeed, except for 2001 (pre-FMD) these are the lowest January figures ever.

The low number of reports in January means that so far this winter the figures have been nearly 10% below average, despite December having over 20% more reports than normal and the summer/ autumn incidence being over 50% above average.

It would be very interesting to hear the thoughts of NADIS veterinarians as to why they think the figures have gone this way.

As January is usually the peak month for ovarian cysts, it is likely that the low levels will continue, except if warm / dry weather prompts an early turn-out onto poor quality grass.

In such cases not feeding additional forage is likely to result in a rise in ovarian cyst reports.

Figure 3: Monthly reports of ovarian cysts for May 2005 to Jan 2006 compared to the average for 1997 to 2004. 

table-3-nadis

 Cattle lameness

The recent changes to the OTMS and casualty slaughter are likely to have more impact on lameness than most other diseases, because whereas lame cows were worth over £300 before the scheme closed they are now worthless.

The unanswered question is whether this is going to mean more lame cows treated by vets or more lame cows struggling for longer before being culled.

So far NADIS reports suggest that there hasn’t been any increase in treatment rates for lame cows, with all four major diseases being below there average.

Much of this low reporting level is due to the dry weather but the lack of an increase strongly suggests that vets are not yet being called out to treat lame cows that would have been culled on the OTMS casualty slaughter scheme.

The changes have only just come in so the lack of an effect so far is not unexpected, but vets and farmers need to get together so that we don’t end up with lots of lame unproductive cows on farm.

Figure 4: Reports by NADIS vets of white line disease for January 2006, the whole of 2005 and average for 1997 – 2004)

table-4-nadis

Richard Laven PhD BVetMed MRCVS
Copyright © NADIS 2006           www.nadis.org.uk

FURTHER INFORMATION SPONSORS’ LINK
• To find out more
about lungworm, click here

huskvac2

FURTHER INFORMATION SPONSORS’ LINK
• To find out more about cattle lameness
click here

tylan Lameness 100


FURTHER INFORMATION SPONSORS’ LINK
• Supporting British
Livestock
click here

mlclogo