Automatic Prestimulation on Dairy Goats: Milking Efficiency and Teat-End Status.

Experiments carried out in dairy cows show that mechanical stimulation prior to milking offers a good release of oxytocin without involving changes in milk yield or a reduction of the milking time. The objective of the present study was to evaluate the effect of automatic prestimulation on milk fractioning, milking duration and milk flows, teat-end status, and vacuum levels at the short milk tubes and in the pulsation tubes of dairy goats. With this aim, three experiments in Latin square design were developed employing goats in different moments of the lactation: one of them at the onset of lactation, one at mid-lactation, and the last at the end of lactation. Two treatments were tested: milking with a mechanical prestimulation of 300 ppm for a 20-s period and milking without prestimulation. Results showed that prestimulation at the end of lactation showed slightly lower average milk flow (kg/min) values (0.53 ± 0.02 vs. 0.60 ± 0.02; p = 0.03) and lower maximum vacuum level values (Kpa) in the pulsation tubes (27.08 ± 0.15 vs. 39.48 ± 0.25; p < 0.01). No other differences were found in the variables related to milking efficiency or teat-end status in the three experiments carried out.