Monday, 28 November 2016
Since attending a series of AHDB Dairy Calf to Calving (C2C) events, Dorset farmers Andrew Wallis and Tony White have implemented changes that have helped boost heifer growth rates and reduce age at first calving.
A greater understanding of the baby calf’s energy requirements to maintain itself and grow has led to improved heifer growth rates and better thrive at Home Farm near Sherborne.
For Tony White and nephew Andrew Wallis, attending an C2C meeting last summer proved the “light bulb moment” that instigated big changes in how they manage their replacements.
Tony explains: “The meeting was on what milk powder was worth in mega joules per day and the calf’s energy requirements to stand still and the requirements to put weight on. That was something we’d never considered.”
The amount of whole milk or milk replacer to feed a calf will depend on its bodyweight, desired growth rate, temperature and the nutritional composition of milk replacer. If the calf does not receive enough energy, she will partition energy into maintaining herself, rather than growing.
Calves less than three weeks old receive nearly all of their energy from milk. It’s not until after this age that they start to receive energy from other feed sources. This means it’s essential that the young calf receives sufficient energy from their milk feed in order to grow. Cold winter temperatures add further challenges as the calf needs more energy to keep warm. Consequently, milk feeding rates need to be raised to ensure calves can both maintain themselves and grow. This is crucial to ensure calves achieve growth rates of between 800g-900g/day to calve in at 90% of their mature weight at the most economic age of 24 months old. If growth rates are not sufficient, heifers could calve later at a cost of £2.87 a head for every day over 24 months.
Challenges at Home Farm
After running through the milk feeding calculations for their calves, Andrew says it was clear that calves were not receiving enough energy, and growth was being compromised (see box).
“Since the Calf to Calving meeting, we’ve looked back and realised that we were underfeeding them,” he explains.
This meant the farm was experiencing higher than desirable levels of calf mortality and poor growth rates in the early milk feeding period, which was impacting on age at first calving.
In the two years prior to the C2C meetings, Andrew and Tony had already put in steps to lower age at first calving after recognising the high cost of calving some of their animals at over three years old. This had involved focusing on feeding the young calves milk replacer instead of whole milk. They also invested in a new calf shed. However, they were conscious that things could be improved. In fact, after attending another AHDB Dairy meeting, they realised their new shed was adding to the problems.
Andrew says: “We put in a new calf shed with concrete panels. But it was suggested that if the calves were lying against the cold concrete panels, this was lowering their body temperature at the height of winter. So what we were feeding wasn’t even meeting maintenance if they were lying against the panels.”
As a result of the meetings, the farm instigated a number of changes to improve performance:
1. Addressing colostrum feeding
In the past, the newborn calf was left with the dam for 24-48 hours and allowed to take its first colostrum feed naturally. Now – depending on what time the cow calves – colostrum is taken from the dam and tested using a refractometer before being fed to the calf. If the dam’s colostrum is poor quality, previously frozen good quality colostrum or colostrum replacer is used. The aim is to feed six litres within the first 24 hours. This ensures calves definitely receive a good volume of quality colostrum when they are most able to absorb immunoglobulins.
2. Increasing milk feeding rates
Calves are fed a higher quality CMR at a higher feeding rate (see box).
3. Using straw bales and calf jackets
To prevent calves from lying against the cold concrete panels, the farm now purposely makes small straw bales and puts them against the panels. They are also put under the doors to prevent drafts. Calf jackets are also used on newborn calves when temperatures drop below 15°C.
4. Cleaning and rest pens
Calves are temporarily moved out of the calf shed once a year to allow it to be steam cleaned and rested. This is essential, particularly in the control of cryptosporidiosis.
5. Weighing regularly
An old beef weigh crate has been dusted off and now used to weigh calves at birth, four weeks old and eight weeks old. A weigh band is then used up to six months of age.
Since making the various changes to heifer management, Andrew and Tony have witnessed marked improvements in performance, which they hope will reduce costs.
Andrew adds: “They look so much better; less “starey” coated and a lot happier. You get a lot less hollering at feeding and they just look better in general.”
Improvements in growth rates have also been marked. Andrew’s records prove that heifers are surpassing targets. For example, one pen averaged 0.9kg/day over 30 days, while a second pen had animals achieving 1.1kg/day, with the worst performing animal hitting 950g/day over 60 days.
Andrew says the C2C workshops have helped improve efficiencies and focus. “It’s reduced heifer rearing costs, and will continue to do so as it’s put it (heifer rearing) at the forefront of our minds. It’s given me a target and renewed interest….Now we have animals calving at 22-26 months. We have a lot more animals in the herd that are younger. They seem to get in calf a lot quicker. We are breeding a very young herd now,” he says.
“By calving younger, we’re reducing costs and hopefully improving fertility as they’ll be in better condition when they come back round to be served. Hopefully, the longevity of the heifers will be better too.”
Changes to calf milk feeding rates at Home Farm, Dorset
Calculations based on CMR feeding at Home Farm found that calves were being underfed which was compromising growth rates.
Before attending the AHDB Dairy Calf to Calving meeting:
Calves were fed 125g/litre of CMR across three litres, fed twice a day (Total: 750g/day). This was delivering 13.96 MJ/day of energy, which was not enough energy to support 700g of growth per day at 15C, let alone achieve adequate levels of growth during cold winter days.
After attending the AHDB Dairy C2C meeting:
Andrew increased the milk feeding rate to 180g/litre over three litres, fed twice a day (Total: 1.1kg/day) with plenty of access to fresh water. This is delivering 20.47 MJ/day and supporting growth of 800-900 grams per day.
As rule of thumb, for every 5°C drop in temperature below 15°C, calves less than three weeks should be fed an extra 50g of CMR to ensure optimum growth rates are achieved.