26 March 2010

8 minute read

The expert review was conducted on 10th December 2009 at the University and consisted of members of the Nottingham Dairy Herd Health Group. The group is composed of a mixture of vets with a specialist interest and demonstrable expertise in dairy herd health.

In the first part of the review, eleven participants were asked to answer a number of questions independently.

In the second part of the review, the questions were shown again and the experts had the opportunity to discuss the questions as a group.

What is downer cow syndrome?

A downer cow is simply a cow that will not rise. The primary causes of a downer cow include traumatic calving, metabolic disorders such as milk fever and toxic diseases such as mastitis.

Often the primary cause can be identified and treated within 24 hours, however should a cow continue to stay down it is likely it has downer cow syndrome or has become recumbent.

It is difficult to assess downer cow syndrome, and there is very little research on it quantifying which indicators are prognostically useful and which aspects of management and treatment are effective.

The accurate diagnosis, prognosis and treatment of recumbency in adult cattle is notoriously complicated, says Mr Huxley, which is partly why he decided to carry out this expert review.

Results

When you first see a down cow, which has been recumbent for under 12 hours, what aspects of the history indicate a poor/ better prognosis?

When considering the aspects of case history that affect prognosis after recumbency for 12 hours, poor prognostic indicators included no attempt to rise, not up since calving and a history of a traumatic event (including dystocia).

Better or good prognostic indicators were attempts to rise, eating and drinking and a younger animal.

When you first see a down cow, which has been recumbent for under 12 hours, what clinical signs indicate a poor/ better prognosis?

When considering clinical signs that affect prognosis after recumbency for 12 hours, signs of shock or a toxic condition, abnormal leg posture and/or lying position, signs of trauma, injury or severe musculoskeletal disease as well as grunting or groaning were considered poor prognostic indicators.

Being bright, alert and responsive as well as having a normal temperature and heart rate were considered good prognostic indicators. A number of the group expressed caution over using the temperature as an indicator if the animal had been down for a period of time on concrete.

Participants agreed that a subjective assessment of the animal's demeanour and attitude based on previous experience was one of the most informative prognostic indicators.

During the general discussion the group agreed with one participant who stated "you know the ones that are going to die".

If you revisited a down cow, which had remained recumbent for three days on a deep bed of straw or at grass, even though the primary cause of recumbency was successfully treated on day one, what clinical signs indicate a poor/ better prognosis?

No attempts to move or rise, not eating and/ or drinking and lateral recumbency/ not sitting in sternal recumbency were considered the strongest indicators of a poor prognosis.

Making attempts to rise or move and eating/ drinking were seen as indicators of a good or better prognosis.

During the general discussion the group agreed that cows which always returned or flipped back to lie on one leg (those incapable of alternating lying sides) had a poor prognosis.

The group also agreed that prognosis at this point was best judged by observing the animals' attempts to rise following encouragement or the animal's response after being lifted to its feet.

A number of the group felt that lifting an animal early was beneficial.

Approximately 75 per cent of the group took a blood sample when they first saw the animal and before any treatment was administered. However most only analysed the sample if the animal failed to rise (to confirm or refute their initial diagnosis).

On average, how many days of recumbency would you allow before recommending that an animal is culled?

The mean and median responses to this were 4.7 and five days respectively (with a range of three to seven). The mode response was also five days.

During the discussion, respondents said that they would change the period depending on the farm and level of management they considered the animal would receive. For example on a farm where the respondents were confident that the animal would be well nursed and the animal remained bright, alert and responsive, periods of up to ten days of recumbency were considered acceptable.

Regardless of when a recumbent cow is examined, are there any clinical signs which always indicate a cow should be culled?

Any traumatic limb injury such as fractures, dislocation or severe soft tissue injury were considered indicators for immediate euthanasia by all respondents.

When considering a down cow, which has remained recumbent even though the primary cause of recumbency was successfully treated on day one, what aspects of nursing on farm and veterinary management have the most impact on recovery?

Availability of food and water, regular turning and lifting as well as provision of a deep soft bed with good footing were among the top aspects of nursing that would impact recovery.

Non-steroidal anti-inflammatory drugs (NSAID) was considered the veterinary treatment that would have the most impact on recovery.

However fluid therapy and hydration management were other treatments that the experts believed would help.

In the general discussion it was brought up in interest that access to good food and water were highly rated. The group agreed that good food and water provision could in fact be being used as a guide to the overall level of nursing the animal was receiving and the fact that many participants stated it, suggests that provision is below their expectations on many farms.

The group also agreed that farm nursing and management had a greater impact on outcome than veterinary treatment once the primary cause of recumbency had been treated.

For the remaining questions, respondents were asked to estimate the level of discomfort on a pain scale where 0 was no pain at all and 10 was the worst pain imaginable.

Throughout the discussion, the group spent time arguing about the level of pain suffered by animals that had been recumbent for three and seven days. Opinions were divided between participants who felt that compression on the dependent leg made it "numb" and therefore not very painful and participants who felt that the compression was likely to be associated with significant levels of pain.

The respondents in the review considered recumbency to be a moderately painful condition; this is in part reflected in the fact that participants considered NSAIDs the most important aspect of veterinary treatment.

Mr Huxley said that scoring the pain associated with recumbency sparked an interesting debate between participants.

There was considerable variation in the median pain score attributed to methods for lifting down cows, with water flotation was considered the least painful (median pain score 3) followed by lifting on an inflatable bag (median pain score 4), lifting using a net (median pain score 5), lifting using two slings (median pain score 6) and final lifting using a Bagshaw hoist (median pain score 7).

It is expected that some discomfort will be caused by the reperfusion and movement of the dependent leg; however the increasing levels of pain association with a number of the methods suggests that the respondents considered that some of the pain is directly attributable to the lifting method itself.

Therefore respondents said that in practice, where possible, the use of the least painful lifting procedure should be used.

Conclusion

The down cow remains one of the most difficult cases to treat in practice. In the absence of other supporting literature it is proposed that the results of this expert review are used as part of the evidence base when formulating action plans for recumbent cattle.