Effects of familiarising heifers to milking shed

Animals that constantly kick off cups, move around, and display other undesirable behaviours during milking may require more attention, distract from the efficiency of the overall milking operation and have a higher potential to cause injuries to farm staff and themselves. If these behaviours could be minimised it could benefit stock people and the well-being of the animals. The aim of our study was to investigate the effect of training to the milking shed on the behaviour and milk productivity of heifers on two commercial dairy farms in the Waikato.

Half the heifers on each farm were trained to the milking shed and the other half were left undisturbed in the paddock. Heifers were trained about one month before calving. The trained heifers had a total of three days training in one week (not three weeks of training as stated in the previous article).  Training involved gradually introducing the heifers to normal shed operations. Each training day consisted of the heifers walking onto the rotary platform and exiting after one rotation, three times. The heifers were introduced to the shed noises, water and gentle touching of the udder while being fed their usual supplements. 

Heifer behaviour during milking was recorded using the flinch, step, kick score (FSK). Behaviour was only recorded while the heifers were in the colostrum herd. Trained heifers stepped more and the severity of the stepping and kicking behaviours were greater compared with the untrained heifers.  Other studies found that heifers positively handled before or at the time of calving displayed less FSK behaviours in response to milking and that heifers that had either the most or the least familiarisation with human handling prior to calving were less likely to move or kick during the first week of lactation. It has been suggested that as animals become familiarized with people and the milking process, behavioural reactivity (e.g. FSK) initially increases until they become tamer (or habituated) and then reactivity consequently decreases. 

In our study, it took longer to attach the cups to trained compared with untrained heifers during the first five days of lactation (18.3 sec vs. 12 sec). The percentage of heifers requiring their cups to be reattached was greater for trained than untrained heifers (22.5 % vs. 14.2 %) during the first week of lactation, but no difference was found during weeks two to six of lactation. The increased time taken to attach the cups and the increased number of times the cups needed reattaching is likely directly associated with the greater number of FSK behaviours displayed by trained heifers. 

Milk yields and milking durations did not differ between untrained and trained heifers irrespective of week of lactation. 

The results from this research suggest that the training protocol used in this study was not adequate to reduce the behavioural response of heifers to the milking process, however results from other studies suggest that positive human handling of heifers before calving can reduce heifer restlessness during milking.

• Suzanne Dowling is AgResearch research technician and Mhairi Sutherland is AgResearch scientist.