In several countries grazing is used for dairy cows, either because of regulations or as a routine management system. It is favourable for cow welfare and attracts the public. However, it might be difficult to combine grazing with automatic milking. Especially the motivation of cows to voluntarily go to the milking unit might be a problem. A prerequisite for all new technology is that a high animal welfare can be maintained within the system. |
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This means that an increased motivation for milking must be achieved solely with positive stimuli. Motivation is always built upon a combination of internal and external factors. Knowledge on the use of these factors in a farm system combining grazing with automatic milking has to be developed. The objectives of this work package are therefore:
Methodology and study materials |
For each one of the three objectives different studies have been planed. The studies are highly interrelated and will interact with each other.
1. Survey on grazing systems in dairy farms using AMS Partners 1 and 6
will carry out this part. Farms with AMS and grazing have during the last
years built up experiences with systems fitted for their specific
conditions. It is therefore an obvious first step to identify bottlenecks,
problems or success with those systems. However, information based on
surveys/questionnaires to farmers is so far very limited.
A sample of dairy farms with at least 3 years experience of grazing and
automatic milking will be selected. In addition to an interview, two
months records of frequencies and distribution of voluntary or forced
visits to the milking unit will be analysed on 10 farms. Data of these
farms have already been collected by partner 1 in a separate study and
will be used in this workpackage. Number and age of the cows, milk yield,
grazing system and supplementary feeding system and distance between the
milking robot and the paddocks will primarily be considered. Interviews
will be held on farms in other countries also.
The work on this part of the workpackage will be carried out as soon as possible, to use the results in the first experiments during the first summer in year 1 (depending on the exact starting date of the project).
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2. Increasing motivation for voluntary milking This investigation by partner 6 will particularly consider the cows' motivation to voluntarily visit the milking stall. The study will be built upon initial tests of the incentive values of each separate stimulus. Tests of motivation for access to each resource will be performed using operand conditioning (in a Skinner box), extinction learning and rate of locomotion to reach a goal resource. |
Examples of resources that can be tested by operand conditioning are foodstuffs with different characters, such as taste, structure and smell. The motivation to obtain other types of sensory stimulation will be tested by rate of locomotion to reach the goal resource, or by the willingness to pay a cost (in the form of aversive stimuli) to get access to the resource. Those resources that are found to have the highest incentive values will be used in the final experiment, which also will involve different distances between pasture and stable. The design of the final experimental will involve the use of a test group and a control group, each containing 50 cows, based on similar (parity, lactation stage, production level) cow pairs, considering natural subgroups. All stimuli involved are of the character of sensory stimulation, each of which is documented to have the potential to affect behaviour and endocrine related systems in cows. Recordings in the field study will be made on behaviour, location in relation to the milking unit and the temporal distribution of location of cows in relation to milking. The studies are planned for three years, with the first year for selection of stimuli, second year a preliminary grazing and stimulation study, and the third year for evaluation on a full scale study All the studies will be carried out at a research station with individual electronic control of all cows in the AMS with regard to food and water intake, milking parameters, activities.
Partner 1 will carry out a 2 years study on a research station with 60 - 70 cows in one AMS unit. The motivation of the cows to come for being milked will primarily be investigated through different levels of feeds in the barn and distances to the pasture. The cows will be identified at feeding gates and when passing into feeding area, lying area or outside.
3. Combination of automatic milking, grazing strategies and density of cows The studies in part 1 and 2 will be complemented by studies by partner 3. Four different grazing strategies will be investigated in combination with different numbers of cows per robot in case studies. The grazing strategies are 24 hours of grazing, night-grazing, daytime grazing and grazing controlled by the cow criteria's. The density will range from 30 to 50 cows per robot. The behaviour of the cows will be observed for 24 hours four times in the grazing period. These data will be analysed together with the data from the automatic milking systems as well as with data from the individual cows in order to relate grazing strategies to animal behaviour over two years in four different commercial farms with a well-functioning automatic milking system and grazing. The investigations will be carried out partly by using the information from the automatic milking systems and partly by direct behavioural observations cow. The registration will be milking frequency, time spent in the field, time spent in the different sections of the barn, diurnal rhythm, lying and eating behaviour, group dynamics and social hierarchy, behavioural and physiological reactions to queuing at the milking robot. Based on the results from the first year, four new strategies will be formulated and used on the 4 farms. Additional data will be collected both from animals which were studied the previous year as well as animals new to the system. The strategies will be compared by an experimental design or as a cohort study.
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© Animal Sciences Group -
Wageningen UR. Last update:
20-02-2008 10:03. |
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