Top tips: Managing calves in groups and using a computerised feeder
A growing number of calves are group housed and fed using computerised feeders during the milk feeding period.
Computerised feeders have many benefits including less labour requirement and the ability to feed the calf high volumes of milk little and often.
Social housing also has its own advantages. High milk fed calves (which are often reluctant to eat starter) – housed in pairs from one week of age – consume more starter before weaning compared to individually housed calves due to peer stimulation¹.
The more starter that is consumed before weaning, the better the rumen development at weaning and subsequent growth after weaning.
Calf diarrhoea and bovine respiratory disease are the most common causes of poor health and death in young calves. Approximately 50% suffer from diarrhoea and around 40-45% are diagnosed with respiratory disease during the milk feeding period (Table 1).
Most of these will be the result of common infections; but there will be many contributory factors such as colostrum intake, management and housing. The latter includes: building design (ventilation, temperature, humidity); cleanliness of pens and feeders; pen size and proximity to other calves and older cows².
Table 1: Incidence of calf disease in pre-weaned calves on UK farms
Recent work carried out at Liverpool University has compared feeding calves restricted volumes of milk replacer twice daily (up to 6L/day until day 56, with weaning at 63 days) with ad-lib feeding (up to 16 L/day until day 63, with weaning at 84 days).
Calves fed restricted volumes were individually housed and fed 5L/day, via individual buckets, until approximately 21 days of age; subsequently, calves were group housed and fed 6L/day via a group trough.
Ad-lib fed calves were group housed and fed via a computerised feeder from birth. As expected, calves fed ad-lib grew faster over the first 12 weeks of life, with the biggest difference within the first three weeks; calves fed ad-lib grew at 0.72kg/day up to three weeks compared to restricted fed calves gaining only 0.17kg/day.
However, more of the calves fed ad-lib via a computerised feeder suffered from diarrhoea and pneumonia (Table 2). There are several possible reasons for the higher level of disease recorded. These include:
- Teat: The use of a single teat for multiple calves can increase the spread of bugs from calf to calf via saliva and nasal secretions;
- Bedding: Calves fed ad-libitum produce more urine and liquid faeces – resulting in wet bedding, which is a source of bugs;
- Exposure to disease: Calves fed ad-lib shared a teat for longer, as they were weaned three weeks later (12 weeks) than the restricted fed calves (nine weeks). The higher level of disease over the milk feeding period will reflect, in part, this longer recording period;
- Housing: Automatic feeding systems should only be used in housing facilities that provide a low background risk for calf pneumonia.
Calf diarrhoea did not have any impact on growth during the pre-weaning and post-weaning periods; there were no calf deaths.
This reflects the early detection and prompt treatment with an oral fluid mixture (throughout which, milk feeding was continued); and highlights the importance of prompt treatment to minimise any long-term negative effects.
Table 2: Incidence of calf disease during the milk feeding period on one dairy farm in north-west England
Other work has shown that the number of calves suffering from diarrhoea and pneumonia is similar when comparing individual manual feeding to group housing with a computerised feeder (Table 3).
Table 3: Incidence of calf disease during the milk feeding period on dairy farms across the US and Canada
Management of calves in groups
A number of management practices have been identified that can help reduce the risk of calf diarrhoea and respiratory disease on farms using automated milk feeders³.
The primary source of nutrition for a calf during the first three-to-four weeks of life is milk, since starter intake is minimal.
As a guide, following the colostrum feeding period of approximately one-to-three days, feed 5L of milk per day until one week of age; then, from one week onwards, offer a minimum of 6L/day. Ensure calves reach their peak milk allowance by two weeks of age at the latest.
Feeding more milk from an early age has several benefits:
- Energy: Feeding more milk provides the calf with more energy – enabling it to mount a better immune response and improve its health;
- Cross-sucking: Providing the calf with enough milk will eliminate cross-sucking (cross-sucking is only an issue for group housing when calves are hungry);
- Competition: Feeding enough milk will satisfy the calf and reduce competition at the feeder. Hungry calves being fed low milk volumes will occupy the feeder for longer, increasing competition;
- Cold weather: Feeding more milk during the periods of cold weather (<10° for a calf aged less than three weeks) helps ensure the calf has enough energy to keep warm as well as grow. If calves are not fed enough, growth rates plummet and they become more susceptible to disease.
Increasing the mixing rate of milk replacer increases the amount of energy and protein provided to the calf, improving its health.
Feeding calves milk with a total solids of at least 13% (130g/L of mixed milk) reduces the number of calves with respiratory disease compared to feeding milk mixed at <10% (100g/L of mixed milk)³.
Always mix milk replacer at a minimum of 12.5% solids (125g/L of mixed milk). If using a milk replacer with a crude protein content of 26%, mix at 15% (150g/L of mixed milk) to ensure the correct balance of energy to protein is supplied.
Always mix milk replacer according to the manufacturer’s recommendations and mix at the chosen concentration consistently.
Many of the bacteria and viruses that are known to be the cause of calf diarrhoea are present in the farm environment.
A good level of cleaning and hygiene with the feeding equipment is essential for all systems. If feeding equipment is not cleaned properly, the milk being fed can become contaminated; calves drinking milk with a high total bacterial count (≥100 000 cfu/ml) are more likely to suffer from diarrhoea³.
Computerised feeders have both automated and manual cleaning functions. Running the automated cleaning function three times a day reduces the incidence of calf diarrhoea, compared to running it only once or twice a day³.
Set your feeder to run the automated cleaning function three times a day, with each cleaning running before the major feed times (e.g. 10:00am, 3:00pm and 10:00pm). Running the automated cleaning function several times a day, together with manual cleaning, will reduce bacterial contamination in the milk being fed.
The use of a single teat for multiple calves poses a risk for poor calf health; bugs can be passed in saliva and nasal secretions from calf to calf via the teat.
Attention must be given to the teats and tubes/pipes on a computerised feeder. At the start of a new calving season, place brand new teats and tubes on the feeder.
The teat should then be swapped for a clean one daily. The teat should be removed; washed with a brush in warm water using washing up liquid; rinsed under running tap water; and placed in a clean bucket with a sterilising solution (e.g. Milton sterilising fluid).
The teat can be left in the bucket for up to 24 hour. If using other products, it is important to ensure the teat is not tainted and rinsed properly.
Bedding quality is critical in terms of reducing the incidence of both calf diarrhoea and respiratory disease; bedding saturated in manure is one of the primary sources of the bugs involved.
Adding fresh bedding every two-to-three days (compared with more than every seven days) reduces the number of calves with diarrhoea³. But, as the depth of the wet bedding increases, calves are more likely to suffer from respiratory disease³. At least 7.6cm of dry bedding should separate the calf from the accumulated manure5.
Always remove dirty bedding frequently to prevent the accumulation of manure (and potential bugs) before adding fresh bedding every two-to-three days.
- Colostrum management: Remember the four Qs (Quickly, Quantity, Quality and sQueaky clean);
- Milk volume: Offer at least 6L/day of milk from one week of age and ensure the peak milk allowance is reached by two weeks;
- Mixing rate: Mix at a minimum of 12.5% solids (125g/L of mixed milk). If using a 26% crude protein milk replacer, always mix at 15%;
- Feeder hygiene: Set the feeder to run the automated cleaning cycle three times per day (at 10:00am, 3:00pm and 10:00pm – before the major feed times);
- Teat: Change and clean the teat daily;
- Bedding: Add fresh bedding every two-to-three days to ensure it remains clean and dry;
- Group size: The ideal group size is 12-15 calves per group, with a maximum of 20 calves per group. Always keep the age range to a minimum (ideal seven days, maximum 21 days);
- Air space: House young calves in a separate unit to avoid them sharing air space with older animals;
- Ventilation: Ensure a ready supply of fresh air;
- Water: Provide clean, fresh, ad-lib water from day one.
Volac’s Feed For Growth Programme provides practical advice, resources and support to help farmers grow better cows. Click here for more information
- Jensen MB, Duve LR & Weary DM (2015) Pair housing & enhanced milk allowance increase play behavior & improve performance in dairy calves. J. Dairy Sci 98:2568-75;
- Johnson KF, Chancellor N, Burn CC &Wathes DC (2017) Prospective cohort study to assess rates of contagious disease in pre-weaned UK dairy heifers: management practices, passive transfer of immunity & associated calf health. Vet Rec Open 4;
- Medrano-Galarza C, LeBlanc SJ, Jones-Bitton A, DeVries TJ, Rushen J, de Passille A, Endres MI & Haley DB (2018) Associations between management practices & within-pen prevalence of calf diarrhea & respiratory disease on dairy farms using automated milk feeders. J. Dairy Sci. 101 In Press;
- Windeyer MC, Leslie KE, Godden SM, Hodgins DC, Lissemore KD, & LeBlanc SJ (2014) Factors associated with morbidiy, mortality, & growth of dairy heifer calves up to 3 months of age. Prev. Vet. Med. 113:231-40;
- McGurik SM (2008) Disease management of dairy calves & heifers. Vet. Clin. North Am. Food Anim. Pract. 24:139–153.