Effect of the settings of two automatic cluster removers (ACRs) on the milking efficiency of Manchega ewes

- We assess the effect of different combinations of milk flow threshold and delay time in two different automatic cluster removers (SG®-mm25® of DeLaval® and Lactoflow®-Dematron® of GeaFarm Technologies®) during milking of Manchega ewes.
- The employment of milk flow threshold 100 g/min increased milking duration without improving the milk fractioning and the employment of milk flow threshold 250 g/min did not reduce milking duration and showed worse results of milk fractioning.
- Further studies are needed to study how ACRs affect the milking duration of the total herd, production and composition of the milk and the sanitary status of the mammary gland.

The implementation of automatic vacuum cutting devices (AVCDs, component of the ACRs, automatic cluster removers) represents one of the most recent advances in small ruminant milking machines. However, there is a lack of scientific studies regarding optimal settings (milk flow threshold, MF, and delay time, DT) for the milking of Manchega ewes. The aim of this study was to assess the effect of different combinations of operating parameters of two AVCDs (LactoFlow®-Dematron® of GeaFarm Technologies® and SG®-mm25® of DeLaval®) on milking efficiency (milking time and milk fractioning), milking routine (cluster falls and double cluster attachment) and mean vacuum drops. Two tests were performed including several latin square design experiments. Regarding LactoFlow®-Dematron® installed in a low-line milking machine, four MF (100, 150, 200 and 250 g/min) were combined with three DT (10, 15 and 20 s) employing 45 ewes on a research farm and regarding SG®-mm25® installed in high-line milking machine, two MF (150 and 200 g/min) were combined with three DT (10, 15 and 20 s) employing 54 ewes on a commercial farm. According to the results, regarding Dematron®-Lactoflow®, it was appreciable that the employment of MF 100 g/min increased milking duration without improving the milk fractioning and the employment of MF 250 g/min did not reduce milking duration. The minimum differences between MF 150 and 200 g/min showed in this test suggest that these levels would be located within the optimal setting of this AVCD. On the other hand, regarding SG®-mm25®, two strategies could be considered, the use of MF 150 g/min combined with high DT to extract the maximum amount of milk or the use of MF 200 g/min combined with short DT to optimize the time employed. Regarding milking routine, no differences were found in any of the test. The increase of both MF and DT showed higher values of mean vacuum drops in the two tests performed.Further studies are needed to study how AVCD affects the milking time of the total herd, production and composition of the milk and the sanitary status of the mammary gland of Manchega breed ewes.