The NADIS disease forecast is based on detailed Met Office data, and regional veterinary reports from 37 farm animal practices and the large animal units at six UK veterinary colleges.

NADIS data can highlight potential livestock disease and parasite incidences 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.

April 2005

Richard Laven BVetMed MRCVS

 
 

ADULT CATTLE

Fertility

Last month saw significant rises in the number of infertility problems. By far the most common problem was cows that had not been seen in heat but when examined by the vet were found to have been cycling. The two main reasons why this occurs are poor heat detection and poor heat expression.

The first is relatively easy to solve, either by increasing the time spent detecting heats outside of feeding and milking times) or by using devices such as tail paint and beacons. Poor heat expression is more difficult to overcome, aids can help but improving underlying nutrition, particularly energy status is likely to be more effective.

As turn-out approaches the number of these cows usually drops, probably an effect of Dr. Green. However it is important to remember that for fertility any change is bad so try and avoid serving cows within two weeks either side of turnout, and never synchronise oestrus during that time.

Endometritis and metritis increased sharply last month, they are likely to remain high until cows begin calving outside. Build-up of infection over the winter is the most common cause of problems.

NADIS vets have also reported that with the increase in cow numbers on-farm the lack of space has meant that many farms have reduced their calving areas to below the minimum required.  Ensuring that calving areas are as clean as possible should now be a priority, especially if environmental conditions mean that you can’t calve outdoors
Spring turnout is the next big challenge for fertility.

Although nutrition and cow well-being often improves after turn-out, conception rates are often poor for the first two weeks. This is because good fertility is reliant on stable conditions. Change (even if it’s an apparent improvement) is bad. Avoid serving cows in the fortnight before or after turn-out unless it is essential, and never try and synchronise oestrus during that time.

Lameness
April and May are key months for digital dermatitis and foul-in the-foot, as turn-out can be associated with increases if the underfoot conditions are poor. The current dry conditions can easily turn wet very quickly this month.

However if conditions do remain dry now is the time to try and hit digital dermatitis hard with an aggressive programme of daily footbathing for the week before and the week after turn-out, with non-antibiotic products such as formalin or zinc or copper sulphate.

This will reduce the number of cases and the severity of the remaining ones and give the normal healing associated with turn-out a head start.

Mastitis
There have been a large number of toxic mastitis cases so far this year. It has not just been the number outbreaks that have been high but also the number of cases per outbreak. This may be linked, like endometritis, to the pressure of increasing herd size without increasing herd space. Prevention is based on effective long acting dry cow therapy (antibiotics or sealants) and good hygiene around calving.

Metabolic disease
So far this year the number of cases of displaced abomasum has been just below the number of cases seen last year. April is usually the peak month for this condition. Hopefully we won’t see the same increases this year as in 2004. Keep an eye on any cow that doesn‘t seem to reach its expected yield and doesn’t quite perform.

These are the cows that are likely to have a DA, particularly if they have other risk factors such as a difficult calving, retained membranes or mastitis near calving. If you can pick them up early they will respond to treatment better and you can implement changes in dry cow management to try and prevent other cases occurring. 
 


Turnout is a time of major change for cows and needs planning for before it occurs.  In particular plan a strategy to prevent grass staggers (hypomagnesaemia). This can be tackled in a number of ways including increasing magnesium in the feed or water, reducing or counteracting high potassium or nitrogen levels, and by management changes to ensure hungry animals do not go outside by ensuring roughage intake is satisfactory to prevent rapid grass intake.

Growing cattle
Almost one third of all cases seen by NADIS vets in this age group were calving problems. Most of the problems were associated with either poor sire selection or with poor management of the pregnant heifer (with heifers being either too fat or too thin).

Calving problems in this age have significant consequences with many animals failing to become economically productive afterwards. Conventional breeding wisdom suggests that breeding replacements from heifers, which tend to have the best genetics, is the best way of maintaining genetic improvement.

However with the genetics of the modern dairy cow now exceeding our ability to sustainably manage her rapid genetic improvement is no longer so essential. It may time to do as the New Zealanders and breed the heifers to easy calving breeds such as the Angus, sacrificing a small amount of genetic improvement but significantly increasing the number of heifers that have more than one lactation before being culled.

Turnout is always a difficult time especially for animals in their first grazing season. Work with your vet to develop a grazing and worming programme that fits in with your management system. 

Pay special attention to preventing husk; in most cases vaccination is the best solution. If you had husk problems last year, take extra care as the winter will have not killed off all larvae. Turnout is also the time to plan your worming regime. While not yet as bad as the problem in sheep, resistance to wormers is becoming more of a problem in cattle. Ask your vet for advice as to the best regime for your farm.

Fluke problems last year were significantly down from the peak of 2002. However as abattoir results show there is still a lot of fluke about now. So, in problem areas dose your cattle in April / May with a flukicide that kills adults to prevent pasture contamination. It will also eliminate flukes that are resistant to triclabendazole, the only flukicide that kills all stages.   
 
Calves

Outbreaks of diarrhoea were common last month. Treatment with antibiotics and fluids was effective in most cases. All of the main diseases including rotavirus, coccidia, and E.coli were seen.  Vaccination for scours is an effective method of control for three of the most important scours, coronavirus, rotavirus and E.coli. If these are present on your farm discuss with your vet whether vaccination is a useful option for you.
 


Copyright © NADIS 2005

 


While every effort is made to ensure that the content of this forecast is accurate at the time of publication, NADIS cannot accept responsibility for errors or omissions. All information is general and will need to be adapted in the light of individual farm circumstances in consultation with your veterinary surgeon


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


FURTHER INFORMATION SPONSORS‘ LINK

If you want to know more about calf pneumonia  click here…

 

FURTHER INFORMATION SPONSORS‘ LINK

If you want to know more about Calf Pneumonia click here…


SPONSORS‘ LINK
Supporting British
dairy farmers


FURTHER INFORMATION SPONSORS‘ LINK
Supporting British
Livestock
click here