Last March Peter and Shelia Cox became the first dairy farmers in the UK to install a new advanced milk analysis tool. .
Since installing Herd Navigator at Mearfield Farm 11 months ago, herd fertility has improved and cow infections are being picked up much quicker, according dairy farmer Mr Cox.
The 135-cow Holstein Friesian herd is milked through two robots and the technology was fitted on to each unit to help monitor cows’ reproductive status and detect the early onset of mastitis and ketosis.
Although Mr Cox notes the system hasn’t been running long enough to draw final conclusions, he is pleased with the results to date.
The tool tracks levels of the hormone, progesterone, with the makers claiming a heat detection rate of 95%-plus and an accuracy rate of 90% for pregnancy diagnosis.
It can highlight individual animals 24 hours before standing heat is observed, to allow for more accurate timing of insemination, they add.
Measuring progesterone levels through milk analysis can also identify barren cows, early abortions and prolonged periods of anoestrus. It picks up on cows with follicular and luteal cysts, allowing early remedial treatment and avoiding a wasted insemination.
Since installation the herd’s calving interval has been reduced from 380 days to 376 days since the installation.
“The progesterone testing was my priority and it has proved highly accurate for diagnosing heat and pregnancy,” says Mr Cox.
In fact, so accurate is the tool that Mr Cox has stopped using his activity monitors.
“The cows used to wear collar-type activity monitors at a cost of £90-£100 each and some are still in use, but they will not be replaced when they fail.”
Mr Cox says the pregnancy diagnosis tool has enabled them to reduce the number of vet visits previously required.
“The vet used to come out weekly to PD the cows and for a few months I used both methods concurrently.
- The farm is owner-occupied and spans 75ha
- The 135 Holstein Friesian herd averages 12,000kg over a 305-day lactation, at 4.1% butterfat and 3.4% protein
- The herd calves all year round
- Cows are housed in cubicles and fed a total mixed ration, with 50% grazed during the daytime over the summer
- Milk is sold to Arla
- Surplus heifers are sold as calves, with the remainder marketed bulling or in-calf
- The herd is milked between two to six and four times every 24 hours, depending on stage of lactation
“However, the computer results followed the vet’s diagnosis so accurately that I have reduced the need for regular PD sessions. Our vets at Calweton like the wealth of information it provides them.”
The breeding policy is focused on using bulls that will produce a type that is suited to robotic milking, with correct udder and teat position and good speed of milking. Selection is confined to high PLI bulls that also have a type index of more than two.
Genomic and sexed semen is used on the heifers, which have themselves been genomically tested for the past 18 months.
Since using Herd Navigator it has also helped them to better target the use of sexed semen.
“The system can even measure quality of heat; if it is strong, a cow will receive sexed semen, with a beef bull used if is relatively poor. Every cow is served, whether she exhibits physical heat or not, because of the accuracy of the heat detection.”
The technology is also helping the farm to pick up mastitis infections in advance, so protocols can be established early on.
Mastitis detection relies on measuring the level of lactate dehydrogenase (LDH) in the sample. In response to the bacterial infection and subsequent inflammation of the mammary gland, the cow’s somatic cell count goes up, triggering the release of a number of enzymes, including LDH.
These enzymes are produced by cells that have been damaged as a result of the body’s attempt to fight off the bacteria using its own white blood cells. As the disease increases in its severity, the level of LDH will rise.
The mastitis detection at Mearfield so far has produced some unexpected results.
“It picks up on udder infections so far in advance that I am beginning to see a pattern, where certain cows become mildly infected and their immune systems fight off the disease; I describe them as “self-curing”. I can then work out treatment protocols for those cows whose immune response is not quite so robust.
“The system is also an excellent tool for making decisions on selective dry cow therapy, giving me extra information on infections during the lactation and deciding whether to use antibiotics or just teat sealant alone.
“However, I have taken a cautious approach to mastitis, as the system is still in its first year. I would use teat sealant only on cows that have had a somatic cell count of below 100 for the past five months and no high LDH readings from Herd Navigator within the same time period. Once my confidence grows, these parameters will be increased, to include more cows to be given teat sealant only.”
The results are also influencing breeding decisions.
“A cow which flags up as a repeat offender, for example, or a cow showing several infections over her lactation, can be ruled out for breeding replacements.”
The Herd Navigator also measures the level of BHB (beta hydroxybutyrate) in milk. The metabolite is linked to the mobilisation of energy from the body’s fat tissue. The main benefit of the test is to pinpoint cows at risk of sub-clinical ketosis.
It is allowing Mr Cox to detect Keotosis early on, before yields are dented.
“Herd Navigator automatically tests milk for ketosis in the first 60 days of lactation,” says Mr Cox. “It can also measure milk urea content, to provide information on whether the ration is over-supplied or under-supplied with protein and non-protein nitrogen
“Early intervention usually means making minor adjustments to the diet, which should improve feed efficiency. Once I have been alerted to an at-risk cow, she will be given propylene glycol when she goes to be milked.
“In a conventional system, a cow would probably have to reach the clinical stage of ketosis, before ketosis is picked up. By that stage, she would be feeling very unwell and her yield would fall quite dramatically. It is unlikely that she would reach her full potential over that lactation. Ketosis used to crop up intermittently, but there has not been a case since the new regime started.”
Savings and payback
Mr Cox says the system is producing a saving a saving of about £100 a cow a year over due to the improvements in cow fertility, health and the considerable reduction in labour.
“I would not be without it now and it would be invaluable on farms with a number of staff, to keep everyone on the same page. I am interested in computers and want to utilise the program in great detail. For anyone who is not so keen, it can be set up to manage the monitoring process and simply produce an action report each morning.”
Herd Navigator Q&A
What is Herd Navigator?
Herd Navigator is an advanced milk analysis tool, from DeLaval.
While cows are being milked, samples are taken from specific milking points – cows can be targeted using a pre-set programme – and are sent one-by-one to an analysis unit. Results are then passed to the farm’s computer.
It can be programmed to alert the user to any potential health issues that have been detected, with the option of producing an action plan for treatment.
What is it compatible with?
It can only be used on farms with DeLaval robotic milkers or parlours.
How many milking units/point can it support?
One Herd Navigator can support 12 robotic units or up to 32 milking points in a herringbone or parallel parlour.
How much does it cost?
The price will vary, depending on cow numbers and testing protocol, but on average the cost is £120 a cow a year, including capital and running costs.
The package includes equipment servicing and sessions with a specialist adviser.