Project code: D-91-17


The objectives of this project are to increase the efficiency of feed, labour and livestock use within calf rearing enterprises in Northern Ireland.  These objectives will be delivered through: 

  1. A better understanding of calf rearing houses within Northern Ireland and the key factors linked to poor environmental conditions, failure to deliver expected growth and excessive labour requirements
  2. A better understanding of the impacts and interactions between level/type of calf nutrition, bedding, calf grouping and environmental conditions.  This knowledge will help inform best practice and refine calf rationing systems to better reflect performance under a range of environmental conditions.
  3. The development and quantification of benefits of independently and robustly proven fixes to existing common calf house designs and rearing systems in Northern Ireland.  Through these ‘fixes’ producers will  provide more favourable environmental conditions to allow high levels of calf health and performance with maximum labour efficiency
  4. The development of blueprints for new modern calf rearing housing that would maximise delivery on both calf and producers considerations. Calf considerations include air quality, social interactions, growth performance, space allowance etc.  Producer considerations include, labour efficiency and flexibility, scalability, cost to build and run, integration within the farmyard, degree of mechanisation etc.  The range of blueprints would be developed to suit the climatic and production system variations within Northern Ireland.

Research Provider: AFBI

Project Lead: Steven Morrison


Calf rearing is one of the most labour intensive activities within dairy and beef farms. Recent AFBI research has highlighted major loss in calves during the first weeks of life, with mortality rates up to 6%, and previous estimations by DAERA were shown to cost the industry £60 million per year (2006).  Additionally, morbidity concerns are highlighted by a recent report from the  Royal Veterinary College in the UK which indicated more than 40% of calves on commercial farms suffer pneumonia.  Research at AFBI has demonstrated that such ill health in early life can lead to reduced growth rates and incur both delayed age at breeding and calving with a depressed level of milk production once they join the dairy contributing to a major loss in production efficiency.

 Calf mortality and morbidity are predominately a function of three areas:

  • Housed environment,
  • Calf management/husbandry and
  • Calf nutrition.

AFBI continues to conduct research through DAERA and/or commercial funding in the area of calf/heifer nutrition.  A series of calf immune system development and calf health projects have recently been completed by AFBI based on both Hillsborough and on-farm research.  However, little or no research has been conducted on the calf’s housed environment either locally or internationally.  Guidelines on space allowance, air speed, humidity, stocking density, grouping etc. are all based on values from the 1970-80s when the scale, housing design, labour and livestock genetics were very much different.

Within Northern Ireland dairy herds have expanded at a rate of 1.7 additional cows per herd per year with major investment in dairy cow accommodation and milking facilities.  Almost 65% of the NI dairy cow population are now within 100 cow+ herds.  This compares to less than 50% of cows in 100 cow + herds in 2007. Disappointingly, investment in calf rearing accommodation has been limited.  This has partly been due to the under appreciation of the importance the first weeks of life are on the lifetime performance and profitability of the dairy animal but also the lack of clear, proven guidance on calf house design from both calf and producer perspectives.  Much of the investment that has taken place has been in the building on very large houses with dual purposes.  Many of these buildings are located based on convenience not best practice and through design will struggle to fulfil the needs of the young calf.  How are these newer multiuse calf building functioning? How are the older calf houses that may have been designed for other purposes or are currently overstocked functioning?

The environment in which the calf is reared not only impacts on the risk of calf mortality, ill health and potential lifetime performance but also impacts on the efficiency in which feed is converted to growth. Calves reared in less than desired temperatures, which will link with humidity, moisture and air speed, will use much more of their energy derived from feed to maintain body temperature.  Feed rationing systems such as NRC 2001, although outdated and in need of refinement, clearly demonstrate the major impact temperature has on calf growth (see table below).  Within this example growth rate is reduced by over 50% if environmental temperature is reduced to zero.

Temperature (°C) Milk feeding level (g/d)

Growth rate expected (kg/d)

0 600


5 600


10 600


15 600


Calf house temperatures within Northern Ireland fall below 10°C on regular basis, as demonstrated by temperature loggers installed within the AFBI calf house. Add in sub optimal air flow, high humidity and moisture and this will result in poor feed efficiency and a high risk of ill health.  How do these interactions impact on feed use efficiency? What impact does level/type of nutrition, bedding material frequency? What impact does pen design, calf grouping strategy?

With expanding herd sizes, greater pressure is placed on efficient use of labour.   High levels of hygiene are critical for successful calf rearing and need to be considered in the design of housing relative to the production system.

Project Outline

A steering group of experts in the area of calf housing will be formed to discuss and agree the specific technical elements of the project.  Their expertise will be utilised within a review of both unpublished and published scientific literature to prioritise areas for the controlled studies at AFBI, Hillsborough and potentially CAFRE, Greenmount.

The project will produce baseline data on the physical, environmental and performance properties from a large number of calf rearing houses in Northern Ireland (initially estimated at 100 farms). Location and orientation data relative to prevailing winds and other buildings/livestock groups will be collected,  by way of thermal imagery, photography, GPS, weather data and satellite imagery.  Evaluation of the environment will involve analysis of the prevalence and type of pathogens in the air, bedding and feeding equipment; air space, air flow and humidity at a range of heights as the calf dynamics change during the season; bedding dry matter, thermodynamics and drainage. Observations of the calves will include their level of social interaction, growth and performance, level and type of nutrition, labour efficiency of the system and overall level of calf health and welfare.  A labour assessment of the calf rearing enterprise will also be conducted.

Within these survey farms,  focus farms (estimated 30 farms) will be selected where environmental interventions will be performed to catalogue and quantify the impact on calf health, welfare and performance in addition to labour efficiency and overall financial cost.  The interventions will provide robust, independent recommendations on how to, ‘fix existing housing,’ based on case studies, which will be made available to all producers. The on-farm intervention studies will be coordinated with controlled AFBI studies where updated environmental requirements, based on modern genetics, nutritional requirements, housing designs and productions systems, will be investigated.  This will provide a blueprint design of calf housing requirements to inform the design of new build or refurbished models.  The information will add to recommendations on husbandry and also produce video case study material for use online and through social media.  Although not built directly into this study, opportunities will exist for additional research projects incorporating precision technologies to monitor calf health, welfare and performance; environmental conditions, pathogen loads and, ‘Smart,’ veterinary medicine administration and recording.



This coordinated project, utilising the skills of academia and industry experts within the area of calf housing will deliver:

  • A comprehensive review of literature and expert opinion on calf housing and environmental management
  • Clear understanding of calf housing and environmental conditions on commercial farms in Northern Ireland and impacts on animal performance, feed efficiency, health and farm labour requirements.
  • A catalogue of main factors impacting the efficiency and effectiveness of calf housing design including retrofit elements
  • Blueprints for new modern calf house design fit for the complex range of NI productions systems and climatic conditions
  • Blueprints for ‘fixes’ to existing common calf house design and rearing systems in Northern Ireland with commercial farm user experience case studies

 The project will provide clear documentation, including commercial farmer case studies, across multiple formats (social media, technical booklets, online designs, and peer reviewed papers) from which industry and advisers can make informed building/calf management decisions. The impacts of good and poor environmental management of calf housing will be quantified with financial, animal health/welfare and labour impacts clearly demonstrated.

In addition, the project through the linkages between CAFRE and AFBI, will build a long lasting local skill base in calf house design and environment management.


Additional Information Provided by the Project

  1. A better understanding of calf rearing houses within Northern Ireland and the key factors linked to poor environmental conditions, failure to deliver expected growth and excessive labour requirements. Without baseline evidence on calf housing relevant for NI production systems, scale and climatic conditions, producers/advisers will not have the information to construct new or modify existing calf housing suited to providing optimal environmental conditions for the calf. 
  2. he development and quantification of benefits of proven fixes to existing common calf house design and rearing systems in Northern Ireland.  Through these ‘fixes’ with case study farms producers will have confidence and assurance to follow their peers and provide more favourable environmental conditions to allow high levels of calf health and performance with maximum labour efficiency
  3. The development of blueprints for new modern calf rearing housing that would maximise delivery on both calf and producers considerations. The component studies at Hillsborough will provide valuable information on optimum calf environmental needs and the interactions with nutrition, bedding and grouping strategies.
  4. The outcome will be a toolkit to be used by producers, veterinarians, advisers to identify housing issues impacting on calf performance but also help select, implement and monitor appropriate changes to housing characteristics.
  5. Hygiene hotspots will be identified which can be targeted within education and training programmes.  In addition these highlighted areas could accelerate innovations and developments in new technologies and practices to reduce identify and reduce these risks.
  6. For the first time we will have an understanding of how the housed environment and hygiene levels within the calf housing change as the calving season progresses.  This will provide valuable insight, highlighting key risk periods that will be associated with workload and climatic pressures during a calving season.  With all year round calving more common the project will be the first to evaluate calf houses throughout the year and ascertaining how they perform under different weather and temperature conditions. 

Anticipated Benefits

It is difficult to quantify the benefits of this project in the short to medium term. An improved understanding of calf house design, effective modifications to common calf house designs in Northern Ireland leading to the delivery of optimal environmental conditions within calf rearing houses will improve:

  • feed use efficiency and help ensure calves grow at target growth rates, breed and calve at optimal ages to deliver maximum lifetime performance
  • labour use efficiency
  • calf health and welfare

If we assume:

317,146 dairy calving’s per year:  10% adoption rate; reduced calf mortality rate from 6% to 4% for those who adopt; incidence of calf scour and pneumonia reduced from a conservative estimate of 30% to 15% for those who adopt leading to fewer vet call out fees, reduced need for additional feed to achieve growth rates (estimated value £10 per calf), reduced veterinary drug use etc.  Labour costed at £8 per hour and with an additional 0.5 hrs per day for 3 days to check/treat sick calves.

These savings in cost for only a 10% adoption rate (based on NI 2016 cow population) would deliver a cost saving of £0.4 million per year.  Calf ill health has been shown to reduce lifetime performance. AHDB published costs of a delayed age at first calving are estimated to cost £175 per calf. Poor heifer health/delayed growth rates as a calf (AFBI research) are shown to affect 30% of calves therefore, improved environmental management of the dairy would expect to decrease this rate to 15% proceeding from a 10% adoption rate by producers.

Similarly, research at AFBI found poor growth as a calf, as a result of ill health and sub optimal growth rate relative to level of nutrition, delayed the age at slaughter and reduced carcass weights.  This was very conservatively estimated to cost £17 per calf and it was assumed to affect 30% of calves. Through better environmental management of the dairy calf this rate would drop to 15% with an overall 10% adoption rate by producers.

The addition of these two elements would result in total cost savings of £0.8 million per year for the preferred option.

With a large number of farms involved in the project and case study material produced and disseminated through multiple formats, we would expect early adoption i.e. year 3/4.  With 80% of NI dairy cows located within only 1800 herds (with 70 or greater cows) uptake by 10% of the larger herds would make significant impacts on the NI dairy calf population. If we conservatively estimate 5% uptake in year 4, increased to 7.5% and 10% by year 6, this would provide a non-discounted benefit in the order of £1.8 million.  The continuation of a 10% adoption rate for a further 4 years (until year 10) would provide a further £3.2 million in benefits. However, we would expect adoption rates to continually increase with benefits continuing indefinitely through improvements to housing design and building as long term investments. Early benefits would be based on modifications to existing housing/environmental management with new designs and functioning housing incorporated later.

Non-monetary benefits include:

  • Reduced incidence of calf ill health, therefore, reduced concern regarding antimicrobial resistance and improved public image with respect to livestock production (particular for high emotive calf production systems)
  • Improved producer lifestyle through more time available for other activities.  This is a result of improved environmental conditions with the calf house delivering better calf performance and reduced incidence of ill health.
  • Clear, proven material relevant to NI from which producers, advisers and policy makers can make informed decisions on calf housing – one source of information with clear concise messages
  • Improved farm yard planning, which may have positive impacts on the performance of other livestock groups and overall labour efficiency
  • Improved marketability of livestock produce through enhanced image.  This is as a result of delivery of optimal environmental conditions for the calf to support efficient feed conversion, high welfare standards and high levels of calf health.