Best combination of pre-stimulation and latency period duration before cluster attachment for efficient oxytocin release and milk ejection in cows with low to high udder-filling levels

Abstract

Experiments were designed to investigate the suitability of a combination of a short manual teat stimulation with a short latency period before teat cup attachment to induce and maintain oxytocin release and milk ejection without interruption. In Experiment 1, seven dairy cows in mid lactation were manually pre-stimulated for 15, 30 or 45 s, followed by either 30 s or 45 s of latency period. It was shown that all treatments induced a similar release of oxytocin without interruption until the end of milking. In particular, the latency period of up to 45 s did not cause a transient decrease of oxytocin concentration. In Experiment 2, milking characteristics were recorded in seven cows each in early, mid, and late lactation, respectively. Because the course of milk ejection depends mainly on the degree of udder filling, individual milkings were classified based on the actual degree of udder filling which differs between lactational stages but also between morning and evening milkings. All animals underwent twelve different udder preparation treatments, i.e. 15, 30, or 45 s of pre-stimulation followed by latency periods of 0, 30, 45, or 60 s. Milking characteristics were recorded. Total milk yield, main milking time and average milk flow rate did not differ between treatments if the degree of udder filling at the start of milking was > 40% of the maximum storage capacity. However, if the udder filling was < 40%, main milking time was decreased with the duration of a latency period up to 45 s, independent of duration of pre-stimulation. Average milk flow at an udder filling of < 40% was highest after a pre-stimulation of 45 s followed by a latency period of another 45 s. In contrast, average milk flow reached its lowest values at a pre-stimulation of 15 s without additional latency period. However, average milk flow after a 15-s pre-stimulation increased with increasing latency period. In conclusion, a very short pre-stimulation when followed by a latency period up to 45 s before teat cup attachment remains a suitable alternative for continuous stimulation to induce milk ejection.

The effect of manual and mechanical stimulation on oxytocin release and milking characteristics in Holstein cows milked 3 times daily

“…Milking unit on-time was shortest for HV90 (245 s) and this was significantly different (P < 0.05) from all other treatments. Kaskous and Bruckmaier (2011) indicated that lag time had no effect on milking unit on-time when proportion of udder filling was >40%; however, increasing the lag time from 0 to 30, 45, or 60 s independent of stimulation time reduced the unit on-time when the degree of udder filling was <40%. Sandrucci et al (2007) found the shortest milking unit on-time when lag times were between 1 and 60 s, whereas Watters et al (2012) reported that when the lag time was >60 s, milking unit on-time decreased in late-lactation cows.…”

“…Milk yield per milking did not differ when comparing 60 s of manual stimulation to 60 s of vibration stimulation (Karch et al, 1988) or when comparing manual stimulation, no stimulation, and mechanical stimulation (Sagi et al, 1980b). Milk yield did not differ within classes of udder filling when comparing lag times of 0, 30, 45, and 60 s (Kaskous and Bruckmaier, 2011).…”

“…Within-trial milk yield, milking unit on-time, milk flow rates, and milk quality by treatments Variable in a large commercial dairy farm. Previously, it was reported that an average milk flow rate was the lowest when no lag time was allowed in conjunction with low degrees of udder filling; however, with an udder filling of >40%, lag time had no effect on average milk flow rate (Kaskous and Bruckmaier, 2011). Kaskous and Bruckmaier (2011) reported that average milk flow rate did increase with each degree of udder filling category; however, significant differences were reported between lag times and milk flow rates only within the category of 20 to 40% udder filling.…”

“…When a lag time of 90 or 120 s and forestripping were involved, >60% of milk was harvested in the first 2 min of unit on-time for late-lactation cows. When the degree of udder filling was <40%, a lag time of 45 s decreased unit on-time independent of how long tactile stimulation took place (Kaskous and Bruckmaier, 2011). Recent data indicated that when lag time is >60 s in Holstein cows milked 3× daily, a reduction in milking unit on-time is seen in late-lactation cows (Watters et al, 2012).…”

“…Manual stimulation of the teat for 15, 30, or 45 s followed by either 30 or 45 s of lag time causes a similar and unchanged oxytocin release throughout milking (Kaskous and Bruckmaier, 2011). When a lag time of 90 or 120 s and forestripping were involved, >60% of milk was harvested in the first 2 min of unit on-time for late-lactation cows.…”