Effects of increased milking frequency during early lactation on milk yield and udder health of primiparous Holstein heifers1

Abstract

In dairy cows, increased milking frequency (IMF) during early lactation stimulates an increase in milk yield that partially persists through the remainder of lactation. However, the effects of IMF on lactation performance and udder health of primiparous heifers have not been clearly established. The objective of this study was to determine the effects of IMF during early lactation on milk yield and composition, udder edema, and teat-end condition of primiparous Holstein heifers. Thirteen heifers were assigned at parturition to unilateral frequent milking (twice-daily milking of the left udder half (2X), and 4-times-daily milking of the right udder half (4X)) from d 1 to 21 of lactation. Heifers were milked twice daily at 0130 and 1330 h, with additional milking of the right udder half at 0430 and 1630 h. Half-udder milk yield and composition were recorded on d 1 and 4, weekly through 35 d in milk (DIM), monthly through 210 DIM, and on d 270±1 of lactation. Udder edema and teat-end scores were evaluated on d 1 and 4, weekly through d 35, and on d 60±1 of lactation. A 1-sided paired t test was used to compare milk yield of 4X- to 2X-udder halves. A 2-sided paired t test was used to test for differences in milk composition, udder edema, and teat-end scores. Overall, 4X stimulated an immediate increase in milk yield. Differential milk yield peaked on d 21 of lactation, with 4X udder halves producing 2.8 kg/d more milk than 2X udder halves (P<0.001). After cessation of 4X, the milk yield differential decreased, but 4X udder halves continued to produce 0.8 kg/d more milk than 2X udder halves through d 270 of lactation (P<0.05). Over the entire lactation, milk component yields and 3.5% fat-corrected milk or energy-corrected milk were greater (P<0.05), whereas somatic cell counts in milk were lower, in 4X udder halves (P<0.05). Udder edema and teat-end condition did not differ between 4X and 2X (P>0.19). In conclusion, IMF during early lactation stimulated a persistent increase in milk yield without negatively affecting several indicators of udder health of primiparous dairy heifers.

Effet de la fréquence de traite sur la production laitière de la vache Zébu Peulh

“…Cependant, le rendement matières grasses du lait et en matières protéiques du lait augmente en raison de l'augmentation de la production de lait. Les mêmes résultats ont été observés par Soberon et al (2011), Wright et al (2013) et Hardin (2015 qui ont trouvé une augmentation significative du rendement en matières grasses du lait et en matières protéiques du lait.…”

Testing the application of an automatic milking system on buffalo (Bubalus bubalis)

“…At this point, as has been evaluated for cows (Erdman and Varner, 1994;De Koning et al, 2002;Wagner-Storch and Palmer, 2003;Wade et al, 2004;Albeni et al, 2005;Speroni et al, 2006;Gygax et al, 2007;Stelwagen et al, 2013;Wright et al, 2013) we want to test the possible correlation between milking frequency of AMS (independent variable) and daily milk yield of AMS (dependent variable) to state if there is an increase in milk yield due to increase of milking frequency. Since the two variables are quantitative and they follow a normal distribution, for this reason, the Pearson product-moment correlation coefficient (r) can be used as measure of correlation, as shown by Hauke and Kossowski (2011).…”

“…It was previously reported that milk yield and flow rate, are dependent on the milking interval (Hogeveen et al, 2001). For cows, an increase in milk yields from 6 to 25% in complete lactations, has been observed when milking frequency is increased from two to three times per day (Amos et al, 1985;Stelwagen et al, 2013;Wright et al, 2013). Various authors observed that in cows milked more than twice per day in AMS, there was a production increase of 12% compared to cows milked twice per day in the conventional system (De Koning et al, 2002;Wagner-Storch and Palmer, 2003;Wade et al, 2004); other researches did not noticed a relationship between the increase of daily milking frequency in AMS and the daily milk yield (Erdman and Varner, 1994;Albeni et al, 2005;Speroni et al, 2006;Gygax et al, 2007).…”

Estimating efficiency in automatic milking systems

“…AMS reduces heavy-workload and allows milking frequency monitoring of each individual cow, based on its production level or lactation stage, without any additional labour costs [12]. Everything else remains unchanged, the cows milked more frequently during lactation, normally produce more milk than the cows milked twice a day [13]. Even if many factors can affect the behavior of dairy cows on a farm, the cows milked by AMS can carry out their daily activities with more freedom and have more interaction opportunities with their environment [14].…”