The effect of 2 different premilking stimulation regimens, with and without manual forestripping, on teat tissue condition and milking performance in Holstein dairy cows milked 3 times daily

Abstract

The objectives were to study the effect of 2 different premilking stimulation regimens, with and without manual forestripping, on teat tissue condition and milking characteristics in dairy cows. In a randomized controlled crossover study, 130 Holstein cows milked 3 times daily were assigned to treatment and control groups. Premilking udder preparation for the treatment group consisted of: (1) predipping with 1% iodine, (2) sequential forestripping of 3 streams of milk per quarter, (3) wiping of teats, and (4) attachment of the milking unit. Premilking udder preparation for the control group was identical except that the forestripping step was omitted. The mean tactile stimulation durations were 16 s and 7 s for the treatment and control group, respectively. The time spent from first tactile stimulus (either forestripping or wiping of teats) to milking unit attachment was kept consistent at 90 s for both groups. The study lasted for 14 d with 2 periods, each consisting of a 2-d adjustment time followed by 5 d of data collection. Machine milking-induced short-term changes to the teat tissue were assessed by palpation and visually. The following milking characteristics were assessed with electronic on-farm milk meters: milk yield (MY), milking unit-on time (MUOT), 2-min MY (2MIN), and time spent in low milk flow rate (LMF). Generalized linear mixed models were used to describe the effect of treatment on the outcome variables. The odds of machine milking-induced short-term changes to the teat tissue were lower for cows that received forestripping compared with cows that were not forestripped (odds ratio = 0.31; 95% confidence interval = 0.22-0.42). Least squares means (95% confidence interval) for cows that were forestripped and animals that were not for-estripped, respectively, were 12.

Vacuum Dynamics as an Alternative Method for Detection of Bimodal Milk Ejection in Dairy Cows

“…Contrary to our expectations, we found no association of BIM VA , BIM LA , and LDT on machine on time. This contrasts with previous studies investigating the effect of different premilking stimulation regimens on bimodality and machine on time showing that an increased frequency of bimodality coincided with increased machine on time [7,22,23]. Differences in study population and analyses may account for the discrepancies between results reported in these studies and the ones reported herein.…”

“…This is consistent with results of a recent study from our group [23]. We found that cows who received forestripping had lower odds of bimodality compared with their herdmates that were not forestripped but failed to detect differences in milk yield between the two groups [23]. Therefore, despite the apparent interrelationship between premilking stimulation, bimodality, and milk yield, the overarching question whether mitigation of bimodality through, for example, adaptation of premilking stimulation to the physiological requirements of individual cows that accounts for differences in lag time (time period from stimulation to milk ejection), size in cisternal cavity, and milk flow potential into account, would result in increased milk yield remains obscure.…”

“…In an earlier study [7], the investigators found that milking without premilking stimulation resulted in more bimodal milk flow curves but had no meaningful effect on milk yield. This is consistent with results of a recent study from our group [23]. We found that cows who received forestripping had lower odds of bimodality compared with their herdmates that were not forestripped but failed to detect differences in milk yield between the two groups [23].…”

“…In the New York study [22], the investigators reported that the frequencies of bimodal milk flow curves in cows who received a preparation lag time of 0, 30, and 90 s, respectively, were 21, 14, and 7%. Further, in a recent study we showed that cows who received a short stimulation time (i.e., 7 s) had higher odds of bimodality as compared to animals who received a stimulation duration of 16 s [23] indicating that stimulation time (i.e., duration of tactile teat stimulation) has an effect on the risk of bimodality. For our study herds average preparation lag times and stimulation times ranged between 57-127 s and 3-6 s, respectively.…”

“…Bimodality has been associated with decreased milking efficiency [7] and reported to cause production loss [10]. Previous researchers studying the effect of different pre-milking stimulation regimens on bimodality and machine on time reported an increased frequency of bimodality together with increased machine on time in cows who received no or less stimulation before milking [7,22,23]. However, none of these studies directly investigated the association between bimodality (as independent variable) and machine on time (as dependent variable).…”