NADIS disease bulletins 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.

Farmers are advised to discuss their individual farm circumstances with their veterinary surgeon.

Condition Scoring Cows To Prevent Disease And Improve Fertility

The NADIS data showed that dry cows last autumn are in variable condition, with some animals too fat, some too thin. Condition scoring is an essential part of management which can identify potential problems before they occur

Why condition score

Dairy cows in early lactation, particularly high yielders, cannot get their energy and protein requirements from food alone. They, therefore use their body reserves to meet this gap, resulting in a loss of body condition and body weight. Cattle that lose more condition and weight after calving are at a significantly higher risk of many diseases including:

¨ Fatty liver

¨ Ketosis

¨ Metritis

¨ Mastitis

¨ Lameness

¨ Cystic ovaries

There is also a significant relationship between fertility and body condition, with cows that maintain their condition having significantly better fertility than cows losing more condition.

Using body condition score (BCS) as an indicator of changing body reserves

The best technique for assessing body reserves is body condition scoring which measures fat cover. BCS is closely related to body composition. The more severe the energy deficit and the longer it lasts, the greater the cumulative energy deficit and the greater the loss of body condition. There is no simple relationship between BCS and liveweight, but as a rule of thumb, a loss of one point in BCS is equivalent to a loss of approximately 50 to 60kg or 10% of body weight. Use change in BCS information to assess energy status of the herd and make dietary changes to minimise excessive loss in early lactation or unwanted gain at the end of lactation. BCS is a better single measure of status than liveweight as changes in liveweight without supporting BCS data can be misleading due to changes in gut fill.

Learning to body condition score

The technique was developed at the National Institute for Research in Dairying and uses an 11 point scale of half points between 0 (very thin) and 5 (grossly fat). BCS is not a completely objective technique, different people will give the same animal a different score, but it is likely that they will give them the same ranking. Thus if one assessor scores one cow as a 2 and another as a 3, a second assessor who scored the first cow as 2.5 is likely to score the second cows as higher (i.e. fatter) than the first. Thus the differences between assessors are relatively unimportant as long as each assessor is consistent, but it is best that within a herd the assessment should be made on a regular basis by the same trained member of staff.

Cows can be scored in any situation which allows the animal to be temporarily restrained e.g. race, crush, AI stalls, abreast parlour or cubicles. BCS is assessed around the tailhead and over the loins:

1) Stand directly behind the animal and assess the fat cover over the tailhead visually and by feel using just one hand

2) Do the same over the loins

3) Make the assessment, to the nearest half point, at the tailhead first and then over the loins.

4) Score the cow according to the tailhead score if the loin score is the same or only half a point different.

5) If the loin score is one point or more different to the tailhead score, adjust the tailhead score up or down accordingly by half a point to give the overall cow condition score.

Table 1 gives examples of the appearance and feel of tailhead and loin areas at different condition scores

Table 1: Appearance and feel of tailhead and loin at different body condition scores (taken from MAFF P612, 1986)

Condition Score	Tailhead description	Loin area description
1	Cavity around tailhead with no fatty tissue between skin and pelvis.	Deep depression in loin, ends of transverse processes sharp to touch with upper surfaces easily felt
2	Shallow cavity around tailhead. Pin bones prominent. A little fatty tissue around tailhead and under skin. Pelvis easily felt.	Depression in loin visible. Ends of transverse processes feel slightly rounded and upper surfaces felt only with pressure
2.5	Shallow cavity around tailhead. Pin bones less prominent with more fatty tissue but pelvis still easy to feel.	Transverse processes feel rounded and the depression in loin is less clearly visible.
3	Fatty tissue easily felt over tailhead area, skin appears smooth. Pelvis can still be felt.	Ends of transverse processes can be felt with pressure but thick layer of tissue on upper surface. Slight depression visible in loin.
3.5	More fatty tissue over the whole area with tailhead becoming filled. Skin smooth and pelvis not easy to feel.	Transverse processes just detectable with a thick layer of tissue on upper surface. Depression in loin almost completely filled.
4	Folds of fatty tissue present. Patches of fat apparent under skin. Tailhead well completely filled. Pelvis only felt with firm pressure.	Transverse processes cannot be felt even with firm pressure. No depression visible in loin between backbone and hip bones.

Condition score targets

Drying off to calving

· Dry off cows in condition score 2.5 to 3.0. (For Friesians 3.5 is acceptable)

· Calve cows in condition score 2.5 to 3.0 (For Friesians 3.5 is acceptable)

· Avoid trying to alter body condition during the dry period.

· Prevent cows becoming too fat at drying off and calving.

· Fat cows at drying off are more likely to have reproductive problems in subsequent lactations.

· Fat cows at calving increase the problem of early lactation energy deficiency.

· Fat cows at calving have more calving difficulties.

· Cows with difficult calvings have reduced production and are more likely to be culled.

· Fat cows at calving eat less

mobilise more body tissue

lose more weight and body condition

have an increased risk of disease

CALVING TO FIRST INSEMINATION

· Aim for condition score 2 to 2.5 at first insemination.

· Fertility may not be compromised unless the cow is extremely thin (BCS 1 or less).

· Very thin cows are likely to take longer to resume ovarian activity and to get in calf.

· Body condition should be stable or improving at the time of insemination.

· Change in BCS is more critical than actual condition.

· Aim to restrict body condition loss to 1 point in the first 6 weeks post calving

· Aim to minimise changes in body condition during lactation and the dry period.

Richard Laven PhD BVetMed MRCVS