Dairy Body Condition Scoring: a key management tool

1 Feb 2018
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Body Condition Score (BCS) is a subjective measurement of the amount of body fat the cow is carrying. This measurement can be taken at any time, with different scores recommended across the differing lactation stages. B with the minimum being: at calving, during early lactation, at service, during late lactation and at drying off.

In the UK, the scoring system is based on a 1-5 scale; with 1 being emaciated and 5 being obese. The scores increase in increments of 0.25. A majority of cows fall into condition scores between 2-4, with those found to be outside this range making up extreme cases. As BCS is directly related to body weight, each 0.5 BCS equates to approximately 50kg of body weight. There is also a significant relationship between backfat thickness (BFT) and total body fat (TBF), as a change of 1mm of BFT is equivalent to 5kg of TBF. Therefore, 10mm of BFT equates to approximately 0.5 unit of BCS.

When conducting BCS with your herd, Table 1 below provides the best indicators for each score, with Figure 1 demonstrating the areas discussed.

Body condition scores and indicators

Score	Indicator
<2	The line from the hooks to the thurl and pins creates a ‘V’ shape Hooks are relatively angular. Corrugations on the short ribs are visible ¾ of the way between the tip of the short ribs and the spine assign Sawtooth spine and ribs are severely under-conditioned
2.25	The line from the hooks to the thurl and pins creates a ‘V’ shape Hooks are relatively angular Corrugations on the short ribs are visible ½ way between the tip of the short ribs and the spine assign
2.5	The line from the hooks to the thurl and pins creates a ‘V’ shape Hooks are relatively angular Pins are angular with a palpable fat pad
2.75	The line from the hooks to the thurl and pins creates a ‘V’ shape Hooks are relatively angular Pins are padded
3	The line from the hooks to the thurl and pins creates a ‘V’ shape Hooks are rounded
3.25	The line from the hooks to the thurl and pins creates a ‘U’ shape Hooks are rounded Sacral and tailhead ligaments are visible and easily seen
3.5	The line from the hooks to the thurl and pins creates a ‘U’ shape Sacral ligament is visible Tailhead ligament barely visible – partly covered in fat
3.75	The line from the hooks to the thurl and pins creates a ‘U’ shape Sacral ligament is barely visible Tailhead ligament not visible
4	The line from the hooks to the thurl and pins creates a ‘U’ shape Sacral ligament not visible Tailhead ligament not visible Thurl is flat
4.25	The line from the hooks to the thurl and pins creates a ‘U’ shape Sacral ligament not visible Tailhead ligament not visible When looking at thurl, tip of short ribs is barely visible
4.5	The line from the hooks to the thurl and pins creates a ‘U’ shape Sacral ligament not visible Tailhead ligament not visible Pins are buried in fat
4.75	The line from the hooks to the thurl and pins creates a ‘U’ shape Sacral ligament not visible Tailhead ligament not visible Hooks are barely visible

Is Breed an influence?

Breed is known to influence body condition score, with research showing Holstein Friesians to have a lower BCS than Jersey and Crossbreds. This is due to dual purpose/crossbred cows tending to have a higher muscle ratio compared to high milk production breeds i.e. Holstein Friesians. Dairy bred cows deposit more fat intra-abdominally, thus altering BCS in relation to muscle content. Furthermore, cows with a high milk yield tend to mobilise more body fat reserves to meet the production demands, making them more likely to have a lower BCS and higher BCS loss during early lactation.

Measuring the cows BCS at drying off and calving is of particular importance as it can aid in transition cow management when the cow is more susceptible to diseases. At both of these stages, the optimum BCS is between 3-3.5 (see Figure 2), providing the cow with ample body reserves during early lactation without being too fat. Calving cows at a higher BSC is also more likely to incur difficulties, along with reducing dry matter intake in early lactation, leading to further condition loss. Higher scored cows are also more prone to metabolic diseases such as ketosis and fatty liver syndrome. On the other side, cows calving at a BCS below the optimum are more susceptible to milk fever, reduced milk yield and reduced fertility. Both thin and fat cows during this stage are also more likely to suffer from lameness and mastitis issues, reducing their lactation performance.

When are cows most likely to lose condition?

In early lactation, cows lose condition during the period of negative energy balance, making it critical to minimise excessive losses. Cows that lose substantial condition during this period have an increased number of days open, along with a lower conception rate at first service (with every 0.5 loss of BCS conception rates falls by approx. 10%). Ideally, cows should lose no more than 0.5 BCS at this stage, with an optimum BCS 2.5-3. By mid-lactation, if a cow has lost condition during the early period then it is important for her to regain a moderate amount up to a BCS of 2.75-3.25 to maintain milk production. During late lactation when the cow is in calf, it is important to prepare her for the transition period by replenishing her body fat reserves. The ideal BCS during this period is therefore 3-3.5.

During university, my research project looked at the relationship between breed, body condition score and calving interval. The results showed Friesians to have a significantly lower BCS than both crossbreds and Jerseys. The study also established a relationship between the cows’ BCS at calving and BCS losses; the higher BCS at calving, the greater the BCS loss in the 3 months post-calving. It was also found that primiparous cows calved at a higher BCS and lost less condition post-calving than multiparous cows.

In conclusion, BCS can be used to help assess problems, and if monitored regularly can ensure that the cow is at the correct score for each stage of the lactation cycle. This, in turn can help to improve overall health and performance, along with achieving a balance between nutrition, production and health.

Written by Rachel Gardner | Dairy Specialist

Posted in Dairy Farming