With the average cost of rearing a dairy heifer estimated at £1819 (Boulton et al, 2017) and a heifer only becoming a profitable animal midway through her second lactation (Hanks and Kossaibati, 2018), it is imperative that there is a strong focus on raising a resilient heifer from the moment she is born. Of the 3.3 million cattle on-farm deaths registered with the national British Cattle Movement Service between 2011 and 2018, 25% of these occurred within the first 3 months of life with dairy calves experiencing higher on-farm mortality rates during this time frame than non-dairy (beef) calves at 6.00 and 2.86% respectively (Hyde et al, 2020).
In the UK the most common cause of calf mortality in calves under 1 month old is cryptosporidiosis (Animal & Plant Health Agency (APHA), 2022), which can often be traced back to shedding of cryptosporidia oocysts in the calving pen environment (Garber et al, 1994). The link between calving pen hygiene and diarrhoea and the need for this crucial stage to be closely monitored and managed in order to successfully rear a dairy heifer has been covered by Mee (2008). Good calving pen hygiene is an essential target for minimising perinatal transfer of other enteric diseases such as Johne's disease (Radia et al, 2013) and respiratory disease pathogens like Mycoplasma bovis (Maunsell et al, 2011). Klein-Jöbstl et al (2014) describe a significant negative relationship in the likelihood of calves getting diarrhoea and the frequency of cleaning the calving pen from a study of 100 Austrian dairy units.
For all cattle, stressful events such as transportation, comingling, entry into a feedlot, and cold stress are associated with increased rates of nasal shedding of M. bovis (Woldehiwet et al, 1990) and other respiratory pathogens (Taylor et al, 2010). Entering the calving pen represents one of the most stressful days of the annual cycle for cows, and increased shedding rates of pathogens from adults can be expected (Stubbs et al, 2011). The combination of physiological status of calving cows causing increased pathogen shedding and environmental factors such as excessive moisture and gross contamination in the calving pen can represent a significant biological disease risk to the neonate (Figure 1).
For calves the calving pen is the primary introduction to the external environment, with all its potential stressors such as high pathogen challenge and low temperatures, exacerbated by wet bedding. Early studies (Heinrichs et al, 1987) reported that approximately one quarter of spot measurements for moisture content of bedding in calving pens were above 10% relative humidity, which was considered unsuitable. However, Pithua et al (2009) reported no difference in calf health parameters when three commercial herds compared single pen calving with multiple cow calving pens, but the authors note that cleaning regimens differed between treatments, which could have confounded results.
In spite of the logic that might associate good hygiene in the calving pen with improved health outcomes for calves, the evidence from farm studies is that a wide range of practices are carried out. Only 18.2% of the 38 farms studied by Jorgensen et al (2017) used disinfectant at the time of cleaning the calving pen, and bedding was removed and replaced between two and 156 times per year, median 20.8 times/year. Straw was the main bedding type (78.0% of farms), followed by cornstalks (12.2%). In a survey of 52 producers on veal calf units, only 12% washed or disinfected the calving area between calvings, and 38% used the calving area for sick or lame cows (Renaud et al, 2018). Medrano-Galarza et al (2018) showed significant associations between increased prevalence of both diarrhoea (OR = 1.85) and respiratory disease (OR = 2.61) in calves where maternity pens were not exclusively used for calving cows. Despite the evidence that calving pen management has some significant impact on subsequent calf health, the reality appears to be that individual producers are not yet focusing on calving pens as a useful area for improvement. The current paper presents data from commercial herd calving pens and suggests that the design, labour and hygiene aspects of calving pens could be usefully improved.
Materials and Methods
A total of 66 dairy farms in Northern Ireland were visited in 2019 on three occasions over a 3 week period to measure and collate data on the environment pertaining to calf management. Full details are reported in Brown et al (2021). Each farm unit was visited on each occasion by one of six staff trained to use the project protocols. The size and type of calving pen, other uses, bedding and cleaning frequency, the hygiene status at the time of visit and the ease of cleaning, were all recorded. Hygiene in the calving pen at the time of visits was rated as:
- Good — well strawed, no damp areas, no sick cows
- Moderate — low level of dirt build-up, mostly well strawed, some damp and no sick cows
- Poor — clear build-up of dirt at animal level, some damp, engrained dirt, used for sick cows.
Calving pens were also rated for ease of cleaning as Yes/No, where No = presence of porous surfaces at calf height, significantly cracked concrete, poor/difficult access (Figure 2). The known health status and vaccination policy of the herd was also recorded, along with the attitude of personnel to changing the calving set-up.
Results
A full description of the results on calf management and housing design in Northern Ireland dairy herds is available in Brown et al (2021). The current paper focuses on issues related only to calving pen environment. Results from the 66 farms are shown in Table 1. Single calving pens were in use on 73% of farms with 66% of all pens (44/66) used only for calving. The remainder were also used for sick cows (27%; 18/66), calf rearing (4%; 3/66) and other livestock (3%; 2/66). Hygiene practices for the calving pen were highly variable. The pen was cleaned after every or every other calving on 15% of farms, weekly or fortnightly (33%), monthly (35%) or every 2 months or more (15%). Disinfectants were used when cleaning pens on 83% of farms (55/66) with 73.6% of those (40/55) measuring disinfectant concentration. Straw bedding was added daily or after every cow in the majority (61%) of cases, with bedding three times per week on 18% and less frequently on 22% of farms. A later question on hygiene suggested that 73% of farms do not routinely clean the pen between calvings.
Table 1. Hygiene management of calving pens
| Variable | Response | % | No. of farms |
|---|---|---|---|
| Calving pen type | Single | 73 | 48 |
| Communal | 27 | 18 | |
| Calving pen bedding frequency | Daily or after every birth | 62 | 41 |
| Three times per week | 18 | 12 | |
| Twice per week | 9 | 6 | |
| Once per week | 6 | 4 | |
| As required | 5 | 3 | |
| Calving pen cleaning frequency | Every/every other calving/daily | 15 | 10 |
| Weekly | 17 | 11 | |
| Fortnightly | 17 | 11 | |
| Monthly | 35 | 23 | |
| 2 monthly or more | 15 | 11 |
The subjective assessments of calving pen hygiene at the time of visits defined 32% as good, 47% as average, and 21% as poor. The minority of calving pens (24%) were considered not easy to clean because of the presence of porous materials at calf height, significantly cracked concrete surfaces and/or difficulties of access (Table 2). When the main calf rearer on each farm was asked to respond Yes or No about which aspects of calf rearing they would like to change and improve (Table 3), only 2/66 producers felt that hygiene practice needed changing.
Table 2. Hygiene and ease of cleaning in calving pens (n=66)
| Variable | Response | % | No. of farms |
|---|---|---|---|
| Clean between calvings | Yes | 27 | 18 |
| No | 73 | 48 | |
| Hygiene score | Good | 32 | 21 |
| Moderate | 47 | 31 | |
| Poor | 21 | 14 | |
| Ease of cleaning calving pen | Yes | 76 | 50 |
| No | 24 | 16 |
Table 3. Areas of the pre-weaning calf management that producers would like to improve (n=66)
| Factor | Rearing | Housing | Feed | Hygiene | Birth | Heat |
|---|---|---|---|---|---|---|
| % | 76 | 47 | 33 | 3 | 18 | 8 |
| n | 50 | 31 | 22 | 2 | 12 | 5 |
Brown et al (2021) commented on the large degree of variation observed in the nutrition, hygiene and housing management across the farms in their study, as well as health management practices. There were no significant associations between calving pen variables and farm level descriptors of health or performance.
Discussion
The data from the Northern Ireland study contribute to the overall assessment that management and hygiene practices around calving pens is highly variable. Meganck et al (2015) investigated the protocols used for calving pens in 24 dairy units in Flanders and the Netherlands. Over half of the farms using calving pens (8/13, 62%) used the facility for sick animals compared with 27% in the Northern Ireland study, and less than half (6/13, 46%) carried out cleaning and disinfection of the calving pen between calvings. This is three times more frequent than the 15% of farms cleaning and disinfecting between calvings in the Northern Ireland study. Cleaning and disinfecting of hands, calving aids, the rear end of cows and the calf box was more common, which might suggest that the principle of good hygiene is understood but is not widely applied to the pen environment. The physical condition and/or layout of the calving pen environments on almost 25% of the Northern Ireland farms were an impediment to effective cleaning practice.
The farmer participants in the Northern Ireland study did not consider hygiene as a major factor for improvement in calf rearing in spite of national data on the mortality and morbidity of youngstock. Assessment of hygiene practices during a longitudinal study of 28 large dairy herds in Germany found that separate calving pens for shedders and disinfection of the pen after use reduced herd level incidence of Mycobacterium paratuberculosis (Donat et al, 2016). Disinfection of calf pens with hydrated lime has been shown to delay the onset of cryptosporidiosis in calves (Bjorkman et al, 2015), and may provide significant benefits for hygiene in the calving pens. Conversely, a recent systematic review of modifiable risk factors for management of Cryptosporidium parvum (Brainard et al, 2020) found that evidence is limited and mixed about the impact of dams sharing calving pens. Single or shared calving facilities did not appear to influence farm level (n=62) prevalence of C. parvum in young calves (Falkenberg et al, 2022), although farms that had a routine movement of calves out of calving pens had a lower detection rate of C. parvum than farms with no routine (19.6% vs 33.3%, respectively). Evidence about optimal bedding practice was limited and inconclusive. There was, however, a significant relationship between an increase in days between cleaning of calving pens and decreased daily live weight gain of calves across 37 UK farms (Hyde et al, 2021) but no statistical relationship with mortality. The data from farm studies above broadly indicate that there are potential gains to calf health and performance from improved attention to detail and routines around calving pens, as outlined in Box 1 (BS 5502, 2005; Wisconsin, 2013). Box 2 suggests routines and support for good practices.
Box 1.Calving pen details
- Sufficient space for calving cows — at least 16 m2 for single pens, 12 m2 per cow in group pens
- Use only for calving
- Do not keep sick cows in the calving pen
- Provide good ventilation and ability to mitigate heat stress
- Daily — remove gross contamination and bed up
- Often — clean out fully, at least every 21 days
- Provide local drainage and wash hoses and prevent ingress of dirt from other pens
- Consider different surface options for calving cows — if straw cannot be kept dry look at sand or rubber
- Situate where it is convenient and therefore likely that staff can observe frequently
- Lighting standard to 50 lux and inspection lighting at hand to 300 lux
- Ensure calved cows and newborn calves are removed from the calving area in a timely manner
- Provide sufficient drinking and feeding space with suitable ration for the freshly calved cow
- Water should be tepid (10 to 20oC), 0.85 m above floor level, of good quality and with a minimum flow rate of 10 litres/minute
- Provide suitable handling facilities in the calving pen or immediately adjacent so that cows can be restrained and examined if dystocia occurs
(BS5502: Part 40, 2005; Wisconsin, 2013)
Box 2.Calving pen routines and reasons
Remove all organic material
| 1. Clean pen |
|
WHY? When a calf is born it is immunologically naïve with a lack of transplacental antibodies. It is imperative therefore that the calving pen is as clean and hygienic as possible. Organic matter cannot be effectively disinfected so needs removing, by hand where necessary, in order for cleaning/disinfection to have the desired impactIncrease frequency of cleaning out during busy calving periods. Use a disinfectant that is appropriate for the pathogens on specific farms to ensure known potential disease risks are minimised |
| 2. Dry bedding |
|
WHY? Cows produce a lot of moisture through respiration and excretion. Moisture increases the pathogen load in the calving pen by favouring the environment they need to grow in. Gross faecal contamination poses an immediate risk of infecting the newborn calf with diseases such as Escherichia coli enterotoxaemia/septicaemia, cryptosporidiosis, rotavirus and coronavirus. Cryptosporidia is the leading infectious cause of death in neonatal calves followed by E. coli septicaemia and rotavirus (calf deaths under 1 month old) (APHA lab diagnosis data) |
| 3. Feed and water |
|
WHY? Rehydration is a major target and easy access to clean water is always a benefit. Access to a suitable ration should also be available |
| 4. Use |
|
WHY? The calving pen is dedicated to the calving cow and new-born calf. Under no circumstance should sick cows that are potentially shedding pathogens that may be dangerous to calves or freshly calved cows such as E. coli be housed in this pen. Cows that are sick or down will cause gross contamination of the space, increase stress and impede cow flow within the calving pen. Timing is crucial in maintaining sanitary conditions in the calving pen. ‘Just in time calving’ involves moving the cow into the calving pen only when feet are visible at the vulva. This ensures cows are not put in the calving pen just in case, for example overnight, grossly contaminating the environment over a period of time. This method requires frequent, regular and detailed inspection of the close-up group of cows to limit calves being born in this group rather than the calving pen itself. Calves should be promptly removed to the appropriate housing so that there are not multiple calves and cows in the pen at any one time where possible |
| 5. Cow flow |
|
WHY? Efficiency and ease of movement results in reduced stress for both the animals and the farm staff. Cows being moved to calve ‘just in time’ should ideally be able to access the calving pen directly from the close-up group. In order to harvest the best possible quality colostrum it is imperative that the cow is milked quickly and cleanly after calving as IgG levels in colostrum decline over time and contamination of colostrum can cause disease in the recipient in both the short and long-term (e.g. cryptosporidiosis and Johne's disease, respectively). The best way to do this is by moving the cow to the parlour and to do so the parlour needs to be easily accessible from the calving pen again increasing welfare of the cow and efficiency of staff |
| 6. Restraint |
|
WHY? This is vital for the wellbeing of both the farm staff, the calving cow and the calf in cases of dystocia. It ensures, where intervention is required, that it can be carried out safely and as cleanly as possible, thereby preventing injury or increasing disease risk. The restraint should be easily accessible at all times and require minimal movement to keep stress to a minimum |
| 7. Equipment |
|
WHY? Equipment needs to be readily available and in a clean state at all times. The ability to clean and disinfect equipment in the immediate vicinity of the calving pen enables this to happen |
Points for the future
There are a number of points the authors suggest for future consideration:
- Improve the basic understanding of cleaning, to include the specific points that organic matter and environmental temperature significantly impact on the ability of disinfectants to be effective
- Provide guidance on the design and layout of the close-up cow and calving pen areas suitable to herds of various sizes.
Conclusions
The evidence from commercial dairy farms is that routines and detail around calving pens and calving pen management are highly varied. There is clear evidence that the calving pen is an area of risk of disease transmission but hygiene practices are again wide ranging with evidence that some facilities are not easy to clean. Guidance for the design and management of calving pens is available, and guidance on individual farm hygiene protocols from veterinary practices would provide a valuable support to calf health.
KEY POINTS
- Calf pen management and hygiene is highly varied in practice, with a significant proportion of farms with room for improved performance.
- Available research on calving pen management and subsequent impact on calf health is either conflicted by the wide range of values of independent variables or is clear that good hygiene can significantly reduce the risk of pathogen transfer.
- Many facilities are difficult to clean effectively and with the resources available, and the layout of some calving pens (by size or shape) make it unrealistic to expect good hygiene. Suggested target is two or more individual pens designed for frequent cleaning, adjacent to the close-up yard.
- Individual calving pens require >12 ft x 12 ft, approximately 4 m x 4 m, easy clean with local drainage, good drinking water access, fresh feed, good lighting and access to restraint equipment.
- Group calving pens may appear easier to manage than multiple, smaller pens but they carry increased risk of infection of neonates.