The Robots Are Coming

Background

Since commercialisation in 1992, the AMS has become an established management system, particularly in North Western Europe, and recent figures indicate approximately 10,000 commercial farms using one or more AMS to milk their cows. The technology was originally developed with a focus on small family farms with 50 to 150 dairy cows using indoor-based production systems and year-round milking and targeted countries with milk production systems involving high-yielding cows, high milk prices, and high labour costs.

AMS description

The AMS unit consists of a stall with separate entry and exit gates, a feed delivery hopper at the head end, and a robotic arm carrying the teat cleaning device and the milking cups. The AMS can perform the tasks of cow identification, supplementary feeding, teat washing, establishing teat location, milking cup attachment, milking and cup removal all without human intervention. Most cows present themselves for milking by walking to the milking unit and entering the stall, again without direct human involvement. Ideally, cows will come in a steady stream throughout the day and night resulting in almost continual use of the AMS. Instead of being a “batch” process involving a high level of farmer input twice daily, milking can become a continuous “background” activity, where management of the system becomes the primary task and manual tasks are minimized.

Is AMS technology relevant to Irish dairy farms?

The concept of automatic milking could be very relevant to dairy farming in Ireland. There is an anticipated increase in national milk production by 50 per cent in the coming years. However, at the same time, land as a resource is limiting and the quantity and quality of skilled labour are in increasingly short supply. There are a number of fundamental questions being asked on dairy farms at present, e.g. how to expand a dairy herd on a fragmented land base, farm organisation in order to maintain a simple production system and choice of personnel versus automation.

Integration of cow grazing with automatic milking

If automatic milking is to be considered as a serious alternative to conventional milking in Ireland, then it has to operate with a similar cow nutritional strategy and focus on cow utilization of grass. This is the key challenge. However, research on AMS in New Zealand in recent years has indicated that automatic milking is applicable in a pastoral, seasonal system of milk production, particularly with smaller herds and a small number of commercial farms in both Australia and New Zealand have already employed AMS units.

AMS project start-up at Moorepark

The farmlet associated with the AMS consists of a 24 ha milking platform. During the lactation of 2011 (start-up year) there were 63 cows in the system (target 80 cows) with a mean calving date of 15th February (range 1st February-15th March). This herd comprised 25 Friesian, 16 Jersey Friesian cross and 20 Norwegian Red cows as well as two of mixed breed.

The land area was divided into three grazing sections of eight ha each (A, B, C) which are further divided into one ha paddocks. Four main roadways radiate from the centrally located dairy. Water is located at the dairy. Maximum distance to furthest paddock is 750m. The dairy features one Merlin AMS unit installed adjacent to the existing shed.

The infrastructure incorporates a pre-milking waiting and post- milking area. There are three drafting units, two positioned at the entrance to the dairy that draft cows to the pre- or post- milking area depending on readiness for milking, a third positioned at the dairy exit which drafts cows to the holding yard (for treatment or inspection) or to grazing (Section A, B, C). Automatic milk diversion (colostrum, antibiotic) is included and extensive milking and cow information recorded at each milking (e.g. milk yield, milking time, milk flowrate, SCC, concentrate dispensed).

Grassland management

The grass allocation is critical to optimal cow visits to the AMS unit (it can influence too frequent or infrequent cow visits). Cows graze defined areas or portions of each of the 3 grazing sections during each 24 h period. Cows are allocated five kg DM in each of the three grazing sections (A, B and C) over each 24 h period. Cows move between the grazing Sections A, B and C at 1:00 am, 11:00 am and 6:30 pm, respectively. During the May/ June period cows go into grazing areas with grass covers of 1400-1500 kg DM/ha. Pasture mass was estimated twice weekly. Covers greater than 1500 kg DM/ha would discourage cow movement to the AMS unit and may reduce milking frequency. Cows grazed to a post-grazing height of 3.5-4.0 cm. Cows were stocked at an average target of 3.5 cows/ha. All cows received one kg concentrate feed per 24 h period during most of the lactation.

• Milk protein per cent ranged from 3.26 per cent in May to 3.95 per cent in September
• Milk fat per cent ranged from 3.93 per cent in June to 4.66 per cent in September
• Milk lactose per cent was 4.54 per cent in September
• Milk SCC was consistently < 200x103 cells/ml between May and August, and increased to 210x103 cells/ml during September
• There are on average 113 milkings per day, with six milkings per hour between 06:00 and 22:00.

Critical start-up issues and cost of outlay

1. cow selection on udder and teat conformation,
2. cow training takes approximately four days,
3. 0.5 h and 0.25 h to be set aside for routine maintenance checks at morning and evening time every day,
4. liners have to be replaced at three-weekly intervals early/mid stage of lactation,
5. a daily data check to ensure milking of all cows, udder health and overall cow health and
6. good backup service

Cost of AMS unit = 120,000 euro
Cost of yard and roadway infrastructure = 70,000 euro
Maintenance and running costs = 2,500 euro per year

Future research objectives

A main challenge with automatic milking currently is the high capital cost but the concept of combining automatic milking and cow grazing has potential advantages which could have a positive impact on the dairy industry in the long term. These include reduced labour input, management as opposed to manual labour, abilit y to expand cow numbers on fragmented land bases, increased knowledge of cow data to use as a management tool and finally, but importantly, happy cows. However, considerable research needs to be conducted to establish if the concept presents a realistic alternative to conventional milking systems on Irish dairy farms.