Housing challenges often compromise calf-rearing performance, but attention to detail in areas such as nutrition and hygiene can help offset these weaknesses.
Read more: Cow nutrition is critical to calving success
Recently, a project team based at AFBI Hillsborough recorded a variety of different housing systems on commercial farms in Northern Ireland. The study was representative of practices on UK dairy units as a whole and certainly highlighted both strengths and weaknesses in terms of replacement heifer calf management practices.
The ability of a floor under calves to sufficiently drain urine, spilled milk and water is determined by the slope – from the measurements taken, the slope ranged from 0° to 5.2° across farms. The majority of calf houses (92.4%) were classed as naturally ventilated as they did not have mechanical ventilation present; however, a large proportion had inadequate inlet and outlet areas (53%) to achieve natural ventilation. Additionally, 53% of the main calf houses were adjoined to other livestock buildings meaning that natural ventilation would be further compromised. Space allowance in group pens averaged an ample 3.4m2/calf, but on a small number of farms increasing space allowance would benefit the calves.
Despite a variety of housing challenges, it was reassuring that the researchers noted that a majority of farms (77.2%) were feeding three litres or more of colostrum to their newborn calves as a first feed. With only 3% of the farms left the calves to suckle the dam after birth, it shows progressive colostrum management from farmers to give calves the best start.
Regular measurement of the quality of the colostrum was only carried out by a small number of units (13.65%). This is important to ensure the calf is receiving enough immunoglobulins, as well as giving you an insight into general colostrum quality from your herd. This can be easily done by investing in a simple refractometer.
More than 80% of units in the study were feeding calf milk replacer, primarily through teat feeders. Automatic milk feeders were being used on just over 20% of farms; whilst most farms were mixing their milk powder within 90%- 110% of the targeted concentration (average of 152g per litre), peak volume feeding rates varied significantly.
Consequently, it always pays to buy a calf milk replacer from a trusted supplier; a variety of milk replacer products (n =25) were being used on the farms studied, with protein levels varying from 20% to 26% and fat level from 16% to 20%.
Fundamentally though, provided your colostrum management and feeding protocol is sound – and your calves have access to fresh water, roughage, and a palatable starter concentrate – we know that feeding a good heifer calf a minimum of 900g of calf milk replacer daily will allow you to meet optimum rearing targets. Peak milk volume fed ranged from four litres to eight litres per day (median allowance: six litres per day) across the 66 farms and the difference in energy intake may have significantly impacted on the performance of the calves on some of the units.
The AFBI project, which I advised on, also highlighted that relatively simple and inexpensive improvements in hygiene could be delivered on many farms. One aspect that was noted was that a large proportion of units did not use or measure disinfectant when cleaning calf pens.
Read more: 5 things you need to know about calf housing requirements
Whilst many dairy farms across the UK are hamstrung by antiquated or inadequately designed buildings – where the calf-rearing environment is perhaps less than ideal – improving attention to detail in some of these nutrition and hygiene areas will help offset some of these disadvantages.
There is a lot you can do to improve the situation and certainly, increased monitoring of calf growth performance and ill health will help identify patterns of issues and pinpoint weaknesses in your system.
