Every commercial farm has its own aims and parameters, but there are some key breeding goals and culling criteria to drive suckler herd performance and profit.
This is according to AHDB knowledge exchange manager and Nuffield Scholar Sarah Pick, who has visited ranches across the globe to study suckler herd management.
She recommends the following seven areas to focus on when picking out culls.
Factors that influence how strict you can be
- Herd replacement rate: 15-20% in a nine-week breeding period is recommended. See AHDB Optimising suckler herd fertility for better returns
- Breeding period length: ranches opt for a 60-day (three cycles) bulling period
- Whether you want to expand, maintain or decrease numbers
- Quantity and quality of heifers coming through
- The value of cull cows
Research shows that, as well as being a safety risk, excitable cattle have lower fertility due to higher levels of cortisol (stress hormone) in the bloodstream, which affect hormones controlling ovulation and conception. They also wean lighter calves.
A cow’s temperament is highly heritable, so improvements should be seen in future youngstock and heifers.
What to record:
- Behaviour at calving – aggression or unsettled behaviour can be recorded with the calving records
- Watch for cattle when moving them or working them. Some cows don’t become difficult until you need them to co-operate
- Score cows: 1 = docile, 2 = restless, 3 = nervous, 4 = flighty, 5 = aggressive.
- Cull score 5 cows and work from there
- Aim to have a herd of score 1 cows
- Some breeders record the time taken to leave the crush, known as “flight time”. Others record when cows are on their own with a calf.
2. Correct cows/faults
Farmers are good at being strict on feet, locomotion and teats to result in a herd that is easily managed.
Figures from the dairy industry show feet and leg structure and teats are low-to-moderately heritable. Cull out the worst and only retain from the best.
How to record this:
- A management tag can be used to signify a cull
- Red is a popular colour for this job, as it stands out. You start associating red tags with failure
A 50-cow herd will cull up to eight to 10 cows a year (16-20% replacement rate) and a 150-cow herd will cull 24 to 30 cows a year. Not all of these cows will be old, ill-tempered or empty. Be prepared to be strict on structure to get 100% functional cows
3. Calving records
Records in the calving period can be referred back to at weaning to assist culling decisions when you might struggle to remember which cows were a nightmare.
What to record
How to record it
Get your diary/calendar and write down each cycle from the start of the calving date. A cycle is 21 days long (17-24 days).
Record every cow that calves and in what cycle.
Record every sire the female is mated to on the passport of the calves and the herd book. If one cow had a calving problem and the others calved fine with the same sire and same management, there is probably something wrong with that cow.
Calving interval should be recorded to identify the cows that are slipping back in the calving period.
Females that calve in their first cycle, as heifers are much more likely to calve in the first cycle as a cow.
65% or more calving in the first cycle, 25% calving in the second cycle and no more than 10% should calve in the third cycle.
When a cow calves, have a place to record her performance.
Score her ease on the 1-5 scale.
1= unassisted. 2 = rope or light pull. 3 = calving jack. 4 = vet needed. 5 = caesarean.
Mature cows assisted with calvings: Less than 5%.
Assistance suckling or colostrum feeding
Record all cows that need help producing or feeding colostrum to their calves.
Calves need 10% of their bodyweight of colostrum as soon as possible after birth and another similar feed within the first six hours of birth – this takes 20 minutes of suckling.
Still got a calf at the end of calving
Note down cows with calf losses that haven’t been used to foster on to and record the sire to spot trends.
Record the cows that fail to wean a calf and record a reason. Try to break down mortality in calves that died in the first 48 hours and deaths thereafter.
Needs a healthy calf able to grow 1kg/day.
More than 95% weaned calves per cow bred.
4. Pregnancy check
At a cost of less than £5 a cow, pregnancy checking can save on feed and grazing for the productive cows by removing empty cows from the herd early.
Keeping a cow for a year can often cost between £450-£800, which compares to selling a 700kg cow for 125p/kg (£875).
How to record this?
Simple – she’s in calf or she isn’t and if she isn’t in calf she should be fattened and sold after weaning.
More than 95% calves born per 100 females put to the bull
5. Weaning efficiency
Weaning efficiency is the 200-day weight of the calf, divided by the cow’s weight multiplied by 100. It gives you an indication of the efficiency of the cow, her milk, maternal ability and growth genetics.
Mature cow weight – like other carcass, frame and growth traits – is highly heritable (60%).
Cows typically reach mature weight at five years of age. Culling on weaning efficiency will save on feed costs because larger cows have higher energy maintenance requirements.
Knowing cow weights allows you to:
- Set benchmarks for your herd. Heifers should be 65% of mature weight at bulling
- Set daily growth rate targets to ensure they are big enough to bull at 13-15 months
- Calculate rations and stocking rates
- Increase cow numbers and kg output/ha
How to record:
Weigh cows and calves early in the dry period or at weaning time as they are vaccinated to get a reflection of their weight.
- A cow should be able to wean 45% or more of her weight at 200 days. If she can’t, she should be considered for culling.
- As a rough guide, aim for a bodyweight of 680kg.
- AHDB studies found cow weights could be increased for greater carcass revenue to 725kg. However, revenue plateaus at 785kg because of lower fertility and carcass penalties.
6. Body condition score (BCS)
Monitoring BCS is a critical management strategy to ensure cows calve easily, can meet their calf’s needs and hold to service.
How to record:
There are four important times to assess your cows’ condition – autumn/housing, mid-winter, turnout and weaning.
Record body condition score in your herd manager records/software. This will highlight persistently thin or fat cows.
Spring calving cows can be at 2.5-3 and autumn cows need to be at 3 at calving.
One condition score = 13% of a cow’s liveweight, so a 650kg cow will take 80 days to lose or gain half a condition score at 0.5kg/day.
7. Cow age
Research shows a cow’s best years are four to eight. If a cow is nine years old or more, she will produce less-productive heifers and progeny with smaller ribeyes and lighter carcass weights.
How to record:
Use British Cattle Movement Service data or herd book data to draw up a list of old cows to cross reference against other culling offences.
Depends on the quality/quantity of heifers coming in. Scrutinise your old cows and heifers first. First-calved heifers should be culled if not in calf again.