-
Why body condition score (BCS)?
- A good measure of nutritional status (regular scoring can be an early indicator of ill health)
- BCS evaluates all of the 5 freedoms
- Aims to achieve a balance between:
- • Good Welfare
- • Good production/performance
- • Effective but economic feeding
- E.g. 'maximal' welfare might not = best productivity so need to settle on desired/appropriate welfare which shouldn't be less than what they would experience in the wild
- Similarly, need to compromise on productivity as maximal productivity leads to poor welfare
- Why not visually check/weigh?
- Weight/visual appearance is dependent on frame size; breed; gestation; gut fill; wool etc. -> weight/visual check not reliable indicator
-
What is body condition scoring (BCS)?
- A technique for assessing the body reserves of individual farm animals.
- ‘Hands-on’ (manual) and/or visual evaluation -> check whether specific anatomical areas are accumulating enough/too much fat
- Carried out at strategic times to make decisions about husbandry
- Should be repeated at regular intervals to monitor changes -> large changes suggest health is compromised
- A scale of 0-5 is used in farm animals
-
Allostasis
- Allostasis: the process of achieving stability through physiological or behavioural change
- Allostatic load: cost incurred by the body (as a result of exposure to elevated or fluctuating endocrine or neural responses resulting from exposure to stressors)
- > requires energy to cope with load –requires energy to cope
- Sustained exposure to stressors or susceptible individuals
- – Genetic make up
- – Infection
- – Harsh physical or social environment
- – Hypersensitivity to stress– Malnutrition
- – Fluctuating environment sue to stressors such as winter
- Allostatic overload: energetic expenditure > energetic availability
-
Why BCS: Profitability
- Sheep: BCS is a key driver of profit, measured by kg of lambs weaned per hectare
- > Ewes with a BCS of <2 or >4 will not perform to their full ability; bring down whole flock performance; may have poor welfare
- Ideally:
- >To conceive early in the breeding period (autumn -> short day breeders so depends on light availability -> changes reproductive physiology -> lamb at easter)
- >To be multiple-bearing
- >To rear all lambs to weaning
- >To wean heavy lambs
- -> all of which is directly linked to nutritional status
- Prolificacy: how many eggs ovulate
- Flushing: between weaning and onset of breeding season
- Cows: ideally ->
- > Give birth to one calf per year
- > Produce large amounts of milk at body's expense
- > Peak lactation ~60 days after birth (time farmer wants to breed again)
- > Start cycling, express oestrous behaviour and get pregnant as soon as possible after calving
-
When/how to BCS: Sheep
- 2 key times to BCS ewes: at weaning (2 months after lambing) so can manage weaning to mating (diet requirements etc); and at scanning/ultrasound, sheep carrying triplets etc. may need moving to better pastures
- > Management can be tailored to each individual depending on their BCS and other factors
- BCS of 3: start cycling earlier in mating period; higher ovulation rates; higher conception rates
- > Give birth to heavier lambs; have increased mothering ability; produce more colostrum; wean heavier lambs with increased survival rates
- BCS <2 or >4: erratic cycles; don't express oestrus when rams are brought in; fail to conceive; increased foetal resorption
- > Prone to twin lamb disease (pregnancy toxaemia); difficult birth/prolapse; poorer maternal instinct & impaired bonding; impaired thermoregulatory behaviour of lambs; lower lamb survival/weight
1 BCS = 2% of sheep's weight
- How: BCS should be done at the lumbar vertebrae of the spine
- > Animal standing in a relaxed position
- > Find the lumbar spine (short ribs) – directly after the last (13th) long rib
- > Place your thumb on the vertical process (spine) and your other fingers on the horizontal process (short ribs).
- Feel and assess:
- > Sharpness and roundness of both processes
- > Level of fat over the vertical process
- > Level of fat and muscle over the horizontal process
- > The ‘eye’ (or loin) muscle and its fat cover by pressing your fingers between the vertical and horizontal processes
- BCS 0: rarely used-ewe so thin to the point of death. No fat or muscle would be detected.
- BCS 1: The vertical (spine) and horizontal (short ribs) processes are prominent and sharp.
- > The fingers can be pushed easily below the horizontals and each process can be felt.
- > The loin is thin with no fat cover
- BCS 2: The vertical processes (spine) are prominent but smooth.
- > The horizontal processes (short ribs) are smooth and rounded but it is still possible to press the fingers under.
- > The loin muscle is of moderate depth but with little fat cover.
- BCS 3: The vertical processes (spine) are smooth and rounded; the bone is only felt with pressure.
- > The horizontal processes (short ribs) are also smooth and well covered; hard pressure is required with the fingers to find the ends.
- > The loin muscle is full with a moderate fat cover.
- BCS 4: The vertical processes (spine) are only detectable as a line.
- > The ends of the horizontal processes (short ribs) cannot be felt.
- > The loin muscles are full and have a thick covering of fat.
- BCS 5: Neither the vertical (spine) nor the horizontal (short ribs) processes can be felt even with pressure.
- > It would be most unusual to have a ewe with a score of 5 in a commercial flock.
-
When/how to BCS: Cows
- Key times to BCS: Calving, early lactation, at service, drying off
- BCS allows farmer to fine tune dairy herd nutrition and health
- The change in BCS is more important than the one score = Routine scoring is key!
- 1 BCS = 10% of cows weight, target is to lose no more than 1 BCS at lactation (some loss to be expected) Target score should be in range of 2-3.5 throughout life span
- How: always score on the right side as rumen can make them appear fatter. Focus on pelvis backbone and rump
- Step 1: assess the angle between the hook and pin bones - if 'V' shape then =/<3, if 'U' shape >3.
- > If 'V' continue steps if U follow steps further down
- Step 2: observe whether the hook bones are
- angular or rounded - Angular is =/<2.75. Rounded is 3 or >3
- Step 3: observe the fat covering over the pin
- bones. Padded/patted = 2.75
- Step 4: feel the fat covering the pin bones. Fat pad present = 2.5. No fat pad present <2.25.
- Step 5: evaluate the visibility of the short ribs. Visible halfway to spine = 2.25. Visible 3/4 to spine = 2.
- Step 6: evaluate the visibility of the ribs and spine. 3/4 ribs visible with sawtoothed spine < 2
- If > 3
- Step 2: evaluate the fat covering on the tail head and sacral ligaments. Tail head visible = 3.25
- Step 3: observe the fat covering on the tail head and sacral ligaments. Sacral visible but tail head barely = 3.5
- Step 4: evaluate whether ligaments can be seen at all
- > Ligaments covered in fat/not easily seen = 3.75
- > No ligament visible = 4
- > Fatty deposits on rump and leg = 5
-
BCS: horses
- Scale of 0-5 or 1-9 (Hanneke Scale)
- Allows for improved nutritional management, useful for athletes; Abuse cases; Reproduction
- Look and Touch but don’t be fooled by
- • Coat thickness
- • Conformational differences
- • Height
- Check the following:
- 1. Neck Crest: discernable
- 2. Withers: Do not be fooled by naturally prominent withers
- 3. Behind the shoulder: Fat deposits behind the shoulder
- 4. Over the ribs: An extremely thin horse will have prominent ribs easily seen and felt
- > Ideally -> ribs are not visible but easily felt
- 5. Along the midline of the back: One of the first places external fat is laid down
- > Extremely thin horse will have a ridge down its back
- > As the horse gains weight the ridge will flatten out
- 6. At the tail head: Prominent in thin horses
- > Will begin to bulge as a horse moves from fit to obese
-
What impacts BCS?
- Too thin
- • Abuse or neglect
- • Poor quality/not enough feed
- • Consumption of toxic plants
- • Tooth/jaw problems
- • Advanced age
- • Excessive energy expenditure
- • Parasites
- • Gastric ulcers
- Too fat
- • Too much concentrate
- • Not enough exercise
- • Mismanagement
- • Metabolic disorders
|
|
