Body condition score
Body condition score
What is BCS?
Body Condition Score (BCS) is a quick, visual, on-the-spot method for assessing the health, well-being and nutritional status of adult hinds. It is simply an eyeball (and sometimes palpation) assessment of the amount of muscle and subcutaneous fat over the rump and torso of individual hinds when they are in the pens. Palpation is preferable during winter coat phase since a thick winter coat can visually hide poorer body condition.
For hinds in moderately good condition or better, BCS is a reflection of the amount of subcutaneous fat. However, for hinds of poor condition that carry very little fat, it also reflects loss of muscle mass. These characteristics are mostly easily assessed over the rump and hip bone, but also over the length of the spine.
How is BCS measured?
BCS for red deer hinds is assessed on a five-point scale, with 5 representing ‘very good condition’ (fat) and 1 representing ‘very poor condition’ (cachexia or emaciated). However, most farmers assess using half-scores (effectively making it a 10-point scale, e.g. BCS of 3.5).
Most importantly, because BCS is a reasonably subjective assessment of hind condition, each assessor needs to establish his or her own standardised system and calibration to ensure consistency over time. This is achieved by practice, and by relating changes in BCS to deer liveweight changes. BCS can thus become a proxy for weighing hinds frequently.
Massey University developed the BCS standardised chart shown here as a guide to developing skills in assigning BCS to hinds. It is accepted that there will be variation between assessors in the way they assign different scores. However, as a general rule, most assessors are within half a score of each other.
How do I use BCS results?
BCS is used to monitor the nutritional well-being and health of hinds, particularly around the weaning, pre-mating period and the pre-calving period when it is very important to ensure hinds have sufficient fat reserves to reproduce successfully. BCS can be used to set targets to ensure mating success. For example, if the hind BCS target for mating is an average of 4.0 but the pre-mating average is actually only 3.5, the nutritional and weaning management of the hind leading up to mating needs to ensure sufficient live-weight gains to meet the target for mating.
How do changes in BCS relate to changes in hind liveweight?
BCS is a proxy for measuring liveweight changes in hinds. However, it is important to establish how changes in BCS relate to changes in liveweight. This may necessitate some early calibration for assessors whereby they both BCS and weigh hinds at the same times. Once the assessor has a feel for the relationship, then BCS can become the primary tool for nutritional management of hinds.
As a rule-of-thumb, a unit change in BCS equates to 8-10 kg change in liveweight for adult hinds.
Substantial and rapid loss in BCS in individual hinds can signal major health issues or severe biological challenges. For example, if a hind undergoes a change from 4.0 to 1.5 over a matter of weeks or months, this usually indicates a severe health issue (e.g. clinical Johne’s disease). However, BCS losses of this amount also occasionally occur due to the demands of lactation over periods of severe drought, particularly for old hinds.
What are the limitations to using BCS?
Because BCS largely reflects fairly substantial changes in subcutaneous fat, it is primarily a tool for use on adult deer, particularly hinds. Young deer from weaning to R2 stage are generally always lean even if well-grown, and therefore do not exhibit major changes in BCS even if live-weight changes rapidly. It is always preferable to measure live-weight as an indicator of growth and nutritional performance of young deer. For example, liveweight of R2 hinds prior to first mating is highly correlated with puberty success, but this is not reflected in BCS. Most R2 hinds have a BCS of 3.0-3.5 irrespective of their body mass. However, once hinds attain a ‘mature’ status after their first calving, they can undergo substantial fluctuations in body fatness, and BCS becomes a useful tool for their nutritional management.
Some farmers use BCS to assess the wellbeing of adult stags, particularly velvet stags through winter and spring. Due to the grumpy nature of stags over this period, the assessments are general performed in the field, often with the aid of binoculars. This allows appropriate adjustments to their nutrition to improve subsequent velvet production.
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