We all know thin and lame cows are an issue but what are the resulting consequences? Rob Davies tells Laura Bowyer how he has been working with one farm to address the problems.
Vets and dairy farmers are being told they should be using scoring systems to monitor cows and aid management decisions, according to Rob Davies, from Allen and Partners Veterinary Services, Whitland.
Mr Davies has been working with Peter and Michael Smith and their father John, who run an autumn calving herd of 350 Holstein cows at Pelcomb Farm, Haverfordwest. They have been scoring cows for body condition and locomotion for the last two years. Cows are scored weekly and checked by the vet.
Mr Davies says: “At Pelcomb Farm, body condition is measured using the Penn State method, where a score below 2.5 is considered too thin and lameness is measured with a five-point locomotion scoring system, where scores 1 and 2 are sound, while 3 and above are lame.
“The results from the farm have been interesting and revealing. The first thing they highlighted was the disappointingly high number of lame cows in the herd, with about 41 per cent of cows having a locomotion score of 3 or more.”
From here, a plan was drawn up and implemented to tackle the lameness issue. Mr Davies says continual measuring, monitoring and management of lameness rapidly reduced its incidence in the herd.
He says: “The number of lame cows dropped below 15 per cent within six months of instigating the programme. It has continued to improve and currently only 5 per cent of cows are lame.
“We also found a significant effect on the likelihood of these cows becoming pregnant.”
At Pelcomb Farm every cow served is artificially inseminated with the intent of keeping her for at least another lactation. Cows which are considered not fit to breed are not served.
Mr Davies says: “Of the cows confirmed in-calf, only 5 per cent were considered to be too thin with a body condition score less than 2.5. But among the cows which were served but empty, 33 per cent were too thin. So we can see, cows are much less likely to become pregnant if they are too thin.”
This effect was reflected in the calving to conception interval of these cows he says, with the average interval for cows with body condition scores of 2.5 or greater being 110 days. This is compared to 125 days for thin cows with a condition score less than 2.5.
Mr Davies says: “Thin cows take on average 15 days longer to get back in-calf on this farm.
“The case is the same with lameness. Of the cows confirmed in-calf, only 8 per cent were lame with a locomotion score of 3 or more, whereas of the cows confirmed empty, 35 per cent were lame. Again we can see on this farm, cows are much less likely to conceive if they are lame.
“This effect was also reflected in the calving to conception interval of these cows. The average interval for cows with a locomotion score of 2 or less was 108 days, compared to 130 days for lame cows with a locomotion score 3 or more. On this farm, lame cows take on average 22 days longer to get back in-calf than sound cows.”
Furthermore, lame cows with body condition score below 2.5 at the time of pregnancy diagnosis had a calving to conception interval of 145 days. It took thin lame cows 37 days longer than sound, fit cows to become pregnant after calving.
As a result of these findings, Mr Davies says the body condition and locomotion issues of this herd were addressed and are continually being measured, monitored and managed.
|May 2015-April 2016||May 2014-April 2015|
|Average calving first service||70 days||78 days|
|Number served 80 days after calving||64%||54%|
|Number pregnant 100 days after calving||43%||36%|
|Number empty 200 days after calving||10%||21%|
The table above shows more cows were served and conceived earlier than the previous year. It also shows fewer cows were empty 200 days after calving, reflecting significantly less barren cows at the end of the breeding period.
Mr Davies says: “This exercise has shown cows tell us what is happening in the herd. If we take note of this and measure some simple parameters, such as body condition and locomotion, then assess what this tells us and act upon it, vast improvements can be made with time and effort, at little cost. But what does this really mean for the farmer?
“Firstly, through body condition scoring, feed efficiency can be increased by feeding the right cows the right diet, avoiding overfeeding cows in late lactation.
“There will be less empty cows needing to be replaced at the end of the breeding season, reducing costs. Empty cows are enforced culls and reducing these can allow more inefficient cows to be selectively culled instead, improving efficiencies over time.
“Milk yields should also increase as a consequence and yields have increased by more than 1,000kg per cow this year Pelcomb Farm.”