J Dairy Sci
Animal Production Systems group, Wageningen University, PO Box 338, 6700 AH Wageningen, the Netherlands.
Published: January 2017
Shortening or omitting the dry period (DP) can improve the energy balance of dairy cows in early lactation through a decrease in milk yield after calving. Little is known about the effect of a short or no DP on milk yield over multiple lactations. Our objectives were (1) to assess the effect of DP length over multiple lactations on milk yield, and (2) to assess if the prediction of milk yield in response to DP length could be improved by including individual cow characteristics before calving. Lactation data (2007 to 2015) of 16 Dutch dairy farms that apply no or short DP were used to compute cumulative milk yield in the 60 d before calving (additional yield) and in the 305 d after calving (305-d yield), and the mean daily yield over the interval from 60 d before calving to 60 d before next calving (effective lactation yield). The DP categories were no (0 to 2 wk), short (3 to 5wk), standard (6 to 8 wk), and long (9 to 12 wk). The effect of current DP and previous DP on yields was analyzed with mixed models (n=1,420 lactations). The highest effective lactation yield of fat- and protein-corrected milk (FPCM) was observed for cows with a standard current DP (27.6kg per day); a daily decrease was observed of 0.6kg for a long DP, 1.0kg for a short DP, and 2.0kg for no DP. Previous DP did not significantly affect the effective lactation yield. Thus, cows can be managed with short or no DP over consecutive lactations without a change in quantity of milk losses. Cows that received no DP for consecutive lactations had a lower additional yield before calving (-172kg of FPCM), but a higher 305-d yield (+560kg of FPCM), compared with cows that received no DP for the first time. This could lessen the improvement of the energy balance in early lactation when no DP is applied a second time compared with the first time. For the second objective, a basic model was explored to predict effective lactation yield based on parity, DP length, and first-parity 305-d yield (n=2,866 lactations). The basic model was subsequently extended with data about recent yield, days open, and somatic cell count. Extending the model reduced the error of individual predictions by only 6%. Therefore, the basic model seems sufficient to predict the effect of DP length on effective lactation yield. Other individual cow characteristics can still be relevant, however, to make a practical and tailored decision about DP length.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.3168/jds.2016-10963 | DOI Listing |
J Dairy Sci
January 2025
Department of Animal Biosciences, University of Guelph, Guelph, Ontario, N1G 2W1, Canada. Electronic address:
Provision of supplemental concentrate in an automated milking system (AMS) is commonly used to encourage voluntary attendance, however, the motivation to voluntarily milk is highly variable between cows. The objectives of this study were to determine if dairy cow personality is associated with: 1) their short-term response to changes in factors believed to motivate voluntary AMS visits such as udder pressure and provision of supplemental feed (modulated by longer milking intervals or removal of AMS concentrate, respectively); and 2) their milking activity, production, and feeding behavior after returning to pre-treatment AMS milking interval and concentrate feed settings (i.e.
View Article and Find Full Text PDFJ Dairy Sci
January 2025
Department of Animal Science, Iowa State University, Ames, Iowa 50011. Electronic address:
Experimental objectives were to create a chronic inflammatory model to evaluate the effects of persistent immune activation on metabolism, inflammation, and productivity in lactating dairy cows. Twelve lactating Holstein cows (631 ± 16 kg BW; 124 ± 15 DIM) were enrolled in a study with 2 experimental periods (P); during P1 (5 d), cows were fed ad libitum and baseline data were obtained. At the initiation of P2 (7 d), cows were assigned to 1 of 2 treatments: 1) saline-infused and pair-fed (PF; 5 mL intravenously (IV) sterile saline on d 1, 3, and 5; n = 6) or 2) lipopolysaccharide infused and ad libitum-fed (LPS; 0.
View Article and Find Full Text PDFJ Dairy Sci
January 2025
Department of Agriculture, Nutrition, and Food Systems, University of New Hampshire, Durham, NH 03824. Electronic address:
We aimed to evaluate the effects of prepartum supplementation of different I sources (Ascophyllum nodosum [ASCO] meal and ethylenediamine dihydroiodide [EDDI]) on colostrum yield of cows, and blood concentrations of glucose, BHB, and thyroid hormones and growth of dairy calves. Forty multiparous Holstein cows were blocked by lactation number and expected calving date and assigned to 1 of 4 treatments 28 d before parturition: (1) EDDI supplemented (11 mg/d) to a basal diet to meet the NRC (2001) I concentration of 0.5 mg of I/kg of DMI (control = CON [0 g/d of ASCO meal]; actual I concentration = 0.
View Article and Find Full Text PDFJ Dairy Sci
January 2025
Department of Animal Science, College of Agriculture and Natural Resources. Electronic address:
Forty-eight multiparous Holstein cows were used in a randomized complete block design and assigned to one of 4 treatments in a 2x2 factorial arrangement of treatments to determine the effects of supplemental palmitic acid (C16:0) and chromium (Cr) on production responses of early-lactation cows. During the fresh period (FR; 1-24 d in milk), cows were fed one of 4 treatments: (1) a diet containing no supplemental C16:0 or Cr (CON); (2) diet supplemented with an 85% C16:0-enriched supplement (PA); (3) diet supplemented with Cr-propionate (CR); and (4) diet supplemented with a C16:0-enriched supplement and Cr-propionate (PACR). The C16:0-enriched supplement was added at 1.
View Article and Find Full Text PDFJ Dairy Sci
January 2025
Animal and Grassland Research and Innovation Centre, Teagasc Moorepark, Fermoy, Co. Cork, Ireland.
The objective of this study was to investigate the effect of dynamic pulsation settings that increased the open phase and reduced the closed phase of pulsation during the peak milk flow period together with increasing the milk flow rate switch-point for cluster detachment on milking duration and teat condition after milking. The present study filled current gaps in knowledge by informing on the effects of both milk flow rate switch-points and dynamic pulsation together in one experiment, while presenting data on milking performance, strip milk, teat condition and vacuum levels in the cluster during milking. To this end, 4 treatments consisting of different milk flow rate switch-points and pulsator settings combinations were deployed across 4 groups of 24 cows for 8 weeks.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!
© LitMetric 2025. All rights reserved.