ADSA-EAAP PhD Student Travel Award Presentation: Comparing milk yield between cows with different dry period lengths over multiple lactations

Research output: Contribution to conferenceAbstractAcademic

Abstract

To assess economic and environmental consequences of shortening the dry period (DP), we need to be able to compare milk yields of cows with different DP lengths, and to estimate effects on yield over multiple lactations. Milk yield is generally compared using 305-d yields. This measure, however, does not account for additional yield before calving and potentially shorter calving intervals in case the DP is shortened. First, we aimed to develop a measure to compare milk yields between cows with different DP lengths. We defined an ‘effective lactation yield’ as kg of fat-and-protein-corrected milk (FPCM) per cow per day from 60 days before calving to 60 days before next calving. We applied this measure to 817 cows with a standard (49d to 90d), short (20d to 40d), or no DP before 2nd calving, using first parity 305-d yield as a covariate. Compared with cows with a standard DP, 305-d yields were reduced by 2.3 kg FPCM d-1 for cows with a short DP (P<0.05) and by 7.0 kg FPCM d-1 for cows with no DP (P<0.05). Compared with cows with a standard DP, effective lactation yields were similar for cows with a short DP and reduced by 3.1 kg FPCM d-1 for cows with no DP (P<0.05). Second, we aimed to assess the impact of shortening the DP over multiple lactations on effective lactation yield. Lactation data (2007 to 2015) of cows of 16 Dutch dairy farms that apply no or short DP were selected if effective lactation yield, current DP, and previous DP were known. Dry period categories were: no (0 to 2 wk), short (3 to 5 wk), standard (6 to 8 wk), and long (9 to 12 wk). A long, short, or no current DP reduced effective lactation yield, compared with a standard DP. Previous DP, however, did not affect effective lactation yield over multiple lactations. In conclusion, the effective yield enables comparison of yield when DP length and calving interval vary. Moreover, cows can be managed with short or no DP over multiple lactations without increasing yield losses.

Conference

ConferenceJoint Annual Meeting of the American Dairy Science Association®, the Canadian Society of Animal Science and the Western Section of the American Society of Animal Science
CountryUnited States
CitySalt Lake City
Period19/07/1623/07/16

Fingerprint

honors and awards
dry period (lactation)
travel
milk yield
students
lactation
cows
dairy protein
calving
calving interval
lipids
shortenings

Cite this

Kok, A., van Middelaar, C. E., van Knegsel, A. T. M., Engel, B., Hogeveen, H., Kemp, B., & de Boer, I. J. M. (2016). ADSA-EAAP PhD Student Travel Award Presentation: Comparing milk yield between cows with different dry period lengths over multiple lactations. 207. Abstract from Joint Annual Meeting of the American Dairy Science Association®, the Canadian Society of Animal Science and the Western Section of the American Society of Animal Science , Salt Lake City, United States.
Kok, A. ; van Middelaar, C.E. ; van Knegsel, A.T.M. ; Engel, B. ; Hogeveen, H. ; Kemp, B. ; de Boer, I.J.M. / ADSA-EAAP PhD Student Travel Award Presentation: Comparing milk yield between cows with different dry period lengths over multiple lactations. Abstract from Joint Annual Meeting of the American Dairy Science Association®, the Canadian Society of Animal Science and the Western Section of the American Society of Animal Science , Salt Lake City, United States.
@conference{4490070787514a5a9b1b13a00753bc52,
title = "ADSA-EAAP PhD Student Travel Award Presentation: Comparing milk yield between cows with different dry period lengths over multiple lactations",
abstract = "To assess economic and environmental consequences of shortening the dry period (DP), we need to be able to compare milk yields of cows with different DP lengths, and to estimate effects on yield over multiple lactations. Milk yield is generally compared using 305-d yields. This measure, however, does not account for additional yield before calving and potentially shorter calving intervals in case the DP is shortened. First, we aimed to develop a measure to compare milk yields between cows with different DP lengths. We defined an ‘effective lactation yield’ as kg of fat-and-protein-corrected milk (FPCM) per cow per day from 60 days before calving to 60 days before next calving. We applied this measure to 817 cows with a standard (49d to 90d), short (20d to 40d), or no DP before 2nd calving, using first parity 305-d yield as a covariate. Compared with cows with a standard DP, 305-d yields were reduced by 2.3 kg FPCM d-1 for cows with a short DP (P<0.05) and by 7.0 kg FPCM d-1 for cows with no DP (P<0.05). Compared with cows with a standard DP, effective lactation yields were similar for cows with a short DP and reduced by 3.1 kg FPCM d-1 for cows with no DP (P<0.05). Second, we aimed to assess the impact of shortening the DP over multiple lactations on effective lactation yield. Lactation data (2007 to 2015) of cows of 16 Dutch dairy farms that apply no or short DP were selected if effective lactation yield, current DP, and previous DP were known. Dry period categories were: no (0 to 2 wk), short (3 to 5 wk), standard (6 to 8 wk), and long (9 to 12 wk). A long, short, or no current DP reduced effective lactation yield, compared with a standard DP. Previous DP, however, did not affect effective lactation yield over multiple lactations. In conclusion, the effective yield enables comparison of yield when DP length and calving interval vary. Moreover, cows can be managed with short or no DP over multiple lactations without increasing yield losses.",
author = "A. Kok and {van Middelaar}, C.E. and {van Knegsel}, A.T.M. and B. Engel and H. Hogeveen and B. Kemp and {de Boer}, I.J.M.",
year = "2016",
month = "7",
day = "23",
language = "English",
pages = "207",
note = "Joint Annual Meeting of the American Dairy Science Association{\circledR}, the Canadian Society of Animal Science and the Western Section of the American Society of Animal Science : Animals and Science: Big Solutions for Grand Challenges ; Conference date: 19-07-2016 Through 23-07-2016",

}

Kok, A, van Middelaar, CE, van Knegsel, ATM, Engel, B, Hogeveen, H, Kemp, B & de Boer, IJM 2016, 'ADSA-EAAP PhD Student Travel Award Presentation: Comparing milk yield between cows with different dry period lengths over multiple lactations' Joint Annual Meeting of the American Dairy Science Association®, the Canadian Society of Animal Science and the Western Section of the American Society of Animal Science , Salt Lake City, United States, 19/07/16 - 23/07/16, pp. 207.

ADSA-EAAP PhD Student Travel Award Presentation: Comparing milk yield between cows with different dry period lengths over multiple lactations. / Kok, A.; van Middelaar, C.E.; van Knegsel, A.T.M.; Engel, B.; Hogeveen, H.; Kemp, B.; de Boer, I.J.M.

2016. 207 Abstract from Joint Annual Meeting of the American Dairy Science Association®, the Canadian Society of Animal Science and the Western Section of the American Society of Animal Science , Salt Lake City, United States.

Research output: Contribution to conferenceAbstractAcademic

TY - CONF

T1 - ADSA-EAAP PhD Student Travel Award Presentation: Comparing milk yield between cows with different dry period lengths over multiple lactations

AU - Kok, A.

AU - van Middelaar, C.E.

AU - van Knegsel, A.T.M.

AU - Engel, B.

AU - Hogeveen, H.

AU - Kemp, B.

AU - de Boer, I.J.M.

PY - 2016/7/23

Y1 - 2016/7/23

N2 - To assess economic and environmental consequences of shortening the dry period (DP), we need to be able to compare milk yields of cows with different DP lengths, and to estimate effects on yield over multiple lactations. Milk yield is generally compared using 305-d yields. This measure, however, does not account for additional yield before calving and potentially shorter calving intervals in case the DP is shortened. First, we aimed to develop a measure to compare milk yields between cows with different DP lengths. We defined an ‘effective lactation yield’ as kg of fat-and-protein-corrected milk (FPCM) per cow per day from 60 days before calving to 60 days before next calving. We applied this measure to 817 cows with a standard (49d to 90d), short (20d to 40d), or no DP before 2nd calving, using first parity 305-d yield as a covariate. Compared with cows with a standard DP, 305-d yields were reduced by 2.3 kg FPCM d-1 for cows with a short DP (P<0.05) and by 7.0 kg FPCM d-1 for cows with no DP (P<0.05). Compared with cows with a standard DP, effective lactation yields were similar for cows with a short DP and reduced by 3.1 kg FPCM d-1 for cows with no DP (P<0.05). Second, we aimed to assess the impact of shortening the DP over multiple lactations on effective lactation yield. Lactation data (2007 to 2015) of cows of 16 Dutch dairy farms that apply no or short DP were selected if effective lactation yield, current DP, and previous DP were known. Dry period categories were: no (0 to 2 wk), short (3 to 5 wk), standard (6 to 8 wk), and long (9 to 12 wk). A long, short, or no current DP reduced effective lactation yield, compared with a standard DP. Previous DP, however, did not affect effective lactation yield over multiple lactations. In conclusion, the effective yield enables comparison of yield when DP length and calving interval vary. Moreover, cows can be managed with short or no DP over multiple lactations without increasing yield losses.

AB - To assess economic and environmental consequences of shortening the dry period (DP), we need to be able to compare milk yields of cows with different DP lengths, and to estimate effects on yield over multiple lactations. Milk yield is generally compared using 305-d yields. This measure, however, does not account for additional yield before calving and potentially shorter calving intervals in case the DP is shortened. First, we aimed to develop a measure to compare milk yields between cows with different DP lengths. We defined an ‘effective lactation yield’ as kg of fat-and-protein-corrected milk (FPCM) per cow per day from 60 days before calving to 60 days before next calving. We applied this measure to 817 cows with a standard (49d to 90d), short (20d to 40d), or no DP before 2nd calving, using first parity 305-d yield as a covariate. Compared with cows with a standard DP, 305-d yields were reduced by 2.3 kg FPCM d-1 for cows with a short DP (P<0.05) and by 7.0 kg FPCM d-1 for cows with no DP (P<0.05). Compared with cows with a standard DP, effective lactation yields were similar for cows with a short DP and reduced by 3.1 kg FPCM d-1 for cows with no DP (P<0.05). Second, we aimed to assess the impact of shortening the DP over multiple lactations on effective lactation yield. Lactation data (2007 to 2015) of cows of 16 Dutch dairy farms that apply no or short DP were selected if effective lactation yield, current DP, and previous DP were known. Dry period categories were: no (0 to 2 wk), short (3 to 5 wk), standard (6 to 8 wk), and long (9 to 12 wk). A long, short, or no current DP reduced effective lactation yield, compared with a standard DP. Previous DP, however, did not affect effective lactation yield over multiple lactations. In conclusion, the effective yield enables comparison of yield when DP length and calving interval vary. Moreover, cows can be managed with short or no DP over multiple lactations without increasing yield losses.

M3 - Abstract

SP - 207

ER -

Kok A, van Middelaar CE, van Knegsel ATM, Engel B, Hogeveen H, Kemp B et al. ADSA-EAAP PhD Student Travel Award Presentation: Comparing milk yield between cows with different dry period lengths over multiple lactations. 2016. Abstract from Joint Annual Meeting of the American Dairy Science Association®, the Canadian Society of Animal Science and the Western Section of the American Society of Animal Science , Salt Lake City, United States.