Effect of variable traction on the teatcup during machine milking of ewes with or without hand stripping

Abstract

Summary-A system which exerts variable traction on teatcups has been designed so that the traction is strongest 35-40 s after the beginning of the milking. The system also makes it possible to reduce the bending of teats during machine milking. This system (traction system) was compared to normal milking (control system) using 62 Manchega ewes. After weaning (5 weeks), all the ewes were milked with the control system for 5 d (preexperimental) and then divided into 2 groups. Each milking system (control and traction) was assigned to each group at random, over a 10-week period (experimental). Milking occurred twice a day with machine and hand strippings until the fourth week of the experimental period (period 1 and then, hand stripping was omitted between weeks 5 to 10 (period 2) of the experimental period. The production and composition (fat and protein) of total milk did not present significant differences. The traction system tended to decrease residual milk while increasing its fat content; the differences were only significant with respect to fat content (15.7 vs 14.8%; P < 0.05). The traction system improved milk fractioning, increasing machine milk, although not significantly (+9%; P= 0.09), and decreasing machine stripping (-40°/ ; P < 0.001 ) and hand stripping (-30%; P < 0.001 Moreover, this system also increased the milking time (12 s, P < 0.001 When hand stripping was omitted (period 2), the traction system tended to improve milk fractioning as compared with the control system, but total milk and fat yield barely varied (+1.7% and +5.9%, respectively; P > 0.05). The interaction &dquo;milking system by period&dquo; was not significant for any of the variables studied. The traction system increased teatcup falls (13.6 vs 7.7%; P < 0.001 It may also have had some effect on udder health as the somatic cell count increased, although not significantly (P = 0.09). The use of this system also resulted in more ewes (2 ewes vs no ewe with the control system) being culled as a consequence of acute mastitis. It can therefore be concluded that the traction system or simpler systems which exert more constant traction on the teatcups may only be interesting for milking routines without strippings (eg in rotary parlors with automatic cluster removers). New experiments need to be done to confirm whether these systems really affect the incidence of mastitis or if they inevitably produce a significant increase in teatcup falls. machine milking / ewes / stripping / milking efficiency

Influence of the Milking Units on the Pulsation Curve in Dairy Sheep Milking

“…Among the various components of a milking system, the milking units have the greatest influence on the efficiency of milking, efficiency being seen as the complete emptying of the udder and a stable vacuum at the teat-end [ 3 , 4 ]. Other characteristics of the milking units are also important and influence the pulsation curve.…”