United Feeds’ nutritionist Bobby Irwin attended this week’s Alltech annual symposium in Kentucky, during which he gained insights into a number of the latest ideas relating to dairy cow management and heifer rearing.
“Cow Signals is not a new concept,” he said.
“In fact, all the members of the United Feeds’ advisory team have been trained to use these techniques. However, the presentation given by Dr Bert van Niejenhuis to symposium reinforced just how important these methods of visual assessment can be when it comes to implementing improved dairy management systems on-farm.
“The fact is that cows are communicating with us every minute of every day. Each step they take, each gesture they make is telling us how happy or unhappy they actually are.”
Bobby went on to point out that cows need the six freedoms of the pasture at all times, which encompass the provision of adequate feed, water, light, air, rest and space.
“In practical terms this means ensuring that all cows can feed at the same time. Within a housed environment they need 16 hours of 200 lux light and eight hours of darkness. There should be a soft cubicle for every cow. If a cow does not lie down within one minute of entering a cubicle, then it is not fit for purpose. Cows need to rest for a minimum of 12-14 hours per day.
“An important consideration is lunge space. A cow should lunge forward in the stall when she stands up. Lunging activity can be easily seen when cows are at grass.”
He continued: “By putting the comfort of the cows first at all times, they will respond by producing more milk over a longer number of lactations. This has benefits from both a production and cost saving perspective.
“Older cows produce more milk per lactation than their younger counterparts. Lower culling rates will also reduce the need to produce replacements. Heifer rearing is the second largest cost on all dairy farms.”
Professor Jud Heinrichs, from Penn State University, also spoke at the symposium.
He related the results of his most recent research on calf rearing. Among the key advisory points picked up by Bobby Irwin were those of targeting a 23 to 24 month age at first calving and breeding heifers at between 13 and 14 months of age, when they are at 55% of their mature bodyweight.
“Heifers should calve down at between 85% and 90% of their mature bodyweight,” added United’s Nutritionist.
“It was interesting that Heinrichs never referred to absolute bodyweight figures. Rather, he focussed on the percentage of their final bodyweights. In practical terms this will entail farmers actually measuring the bodyweights of their mature cows and then using this as the benchmark target for their own specific heifer rearing programmes.
“It was also interesting that Heinrichs’ research is pointing to daily growth rates of between 800 and 900 grams per day as being optimal for heifers. There is evidence to show that pushing heifers beyond growth rates of 1 kilo per day will impact negatively on subsequent milk yields.”