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Having good herd fertility and plenty of replacement heifers is allowing Charles Clarke to quickly improve genetics in his herd by being particular when selecting cows for culling.
Herd fertility on his farm near Bailieborough, Co Cavan, has improved significantly in recent years. Calving interval is currently 380 days and six-week calving rate for cows and heifers this spring was 93%.
Only 6% of Charles’s cows and 7% of his heifers scanned empty last year and calving spread can’t tighten any further for workload management reasons at calving time.
He told visitors to his farm last week that having low empty rates and a tight calving spread has meant he has been able to cull cows based on production traits. He is able to let cows with poor butterfat and protein levels, low EBIs, heavier bodyweights or any health issues leave the herd.
Charles has let as many of his homebred heifers join the herd as possible in recent years and, at present, 70 of the 120-cow herd are in their first or second lactation.
To make effective culling decisions, Charles has to identify what the ideal cow for his dairying system is and how this compares with his existing herd at an individual cow level.
“I want a cow with a calving interval of less than 370 days. If a cow slips a week or two every year, then she will eventually end up calving at the end of March. For mature body weight, I want 550kg or less,” Charles told visitors last Thursday.
Performance
In 2017, the herd averaged 407kg of milk solids (5,256 litres at 4.13% fat and 3.39% protein) from 869kg of concentrates. Around 200kg more meal was fed last autumn than the previous year due to wet weather. The ideal cow for the Clarke farm produces 450kg MS or more per year from 500kg of purchased feed.
“In time, the milk solids target is doable. Production figures are lower at present because it is a young herd. I am trying to freshen up the herd with the young stock that have higher EBIs and higher milks solids,” Charles said.
Being able to focus on improving production traits is only possible because herd fertility is in a good place. If all replacement heifers were needed to replace a high number of empty cows or late calvers, then Charles would have to be much less picky about which older cows are leaving the herd.
Information
During the three farm walks held on Dairylink Ireland farms this spring, a sample of individual cows were selected from each herd and information on fertility and milk production during each lactation was discussed.
Programme adviser Conail Keown said that decisions about what cows should leave the herd need to be based on this information.
“To improve herd genetics, you need to use the information that is at your fingertips. There is no point taking a quick glance through milk recording figures and putting it in a drawer,” he said.
On Charles’s farm, cow 834 was identified as a strong-performing cow. She is a sixth-lactation cow that has produced 468kg MS (5,750 litres at 4.12% fat and 3.54% protein) on average over her five lactations. She has calved in mid-February every year, has cycled already this lactation, has an EBI of €189 and weighs 478kg.
Cow 861 is a bigger cow, clocking 614kg on the weighbridge last Thursday. She has an EBI of €-78 and her calving dates show slippage of around six weeks across her first three lactations, although this was made up for in her fourth and fifth calvings. The main issue with cow 861 is that her milk solids are poor. Across four full lactations, she averaged 354kg MS (5,750 litres at 3.12% fat and 3.04% protein). When asked what his plans for cow 861 were, Charles said: “Her future is pretty bleak.”
Extra solids
On the Clarke farm, cows are fed flat concentrates throughout the year, so extra milk solids are not associated to additional cost. Taking an average milk price of €5/kg MS, Charles pointed out that 50kg MS less per cow equates to €25,000 over a 100-cow herd.
Cow 3845 was identified as close to Charles’s ideal cow. She is a second calver that has a calving interval of 370 days and produced 432kg MS last year (5,297 litres at 4.37% fat and 3.78% protein). This cow was bought as a calf in April 2015, is 30% Jersey and has an EBI of €173.
Specific sires have not been selected for the 2018 breeding season yet, although Charles says he will use a similar approach to last year with half the bulls Holstein Friesian and the other half Jersey.
He told visitors last week that Jersey genetics are being introduced to reduce cow size and improve fat and protein levels in milk. Charles said sires will be selected based on EBIs for kilos of fat and protein, fertility and maintenance.
Heats are being detected pre-breeding and all cows were tail-painted red two weeks ago. Cows that cycle are given green tail paint and any cows that have not come on heat before breeding starts in a few weeks will be checked by the vet and treated accordingly.
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