|Galvao Jr, Jose - Instituto Federal De Educação Ciência E Tecnologia|
|Rangel, Adriano - Federal University Of Rio Grande|
|Brito, Andre - University Of New Hampshire|
|Silva, Jean - Federal Rural University Of The Semi-Arid|
|Fay Benson, A - Cornell University - New York|
|Hafla, Aimee - Agri-King, Inc|
|Darby, Heather - University Of Vermont|
|Kersbergen, Rick - University Of Maine|
|Brossillon, Vincent - Ecole Normale Superieure (ENS) De Lyon|
Submitted to: American Dairy Science Association Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 5/20/2018
Publication Date: 6/24/2018
Citation: Galvao Jr, J., Rangel, A., Brito, A., Silva, J., Fay Benson, A., Hafla, A., Darby, H., Soder, K.J., Kersbergen, R., Brossillon, V. 2018. Using milksomatic cell score to predict of milk yield losses of organic dairy farms in the Northeast United States. American Dairy Science Association Abstracts. P. 1.
Interpretive Summary: No Interpretive Summary is required for this Abstract. JLB.
Technical Abstract: The objective of this study was to predict milk yield (MY) losses associated with milk SCS in organically certified dairy herds in the northeast region of the United States. Dairy Herd Improvement records of Holstein (HO), Jersey (JE), and Holstein-Jersey crossbred (HO×JE) cows were obtained monthly (May 2012 to June 2015) from 14 herds in New Hampshire (n = 3), Vermont (n = 3), Maine (n = 3), New York (n = 2), and Pennsylvania (n = 3). A total of 14,246 observations including MY (2 to 60 kg/d), DIM (5 to 320 d) and SCS (0 to 9) were obtained. Milk yield and SCS were analyzed using the PROC MEANS procedure of SAS. Milk yield averaged 21.3 kg/d across breeds, and 23.8, 17.7, and 22.3 kg/d for HO, JE, and HO×JE, respectively. As expected, primiparous cows had lower MY (18.9 kg/d) than multiparous cows (22.4 kg/d). The SCS for all herds averaged 2.54; it was greatest for HO (2.59), intermediate for JE (2.50), and lowest for HO×JE (2.46), and 2.20 and 2.68 for primiparous and multiparous, respectively. The following linear regression model was obtained using the PROC REG procedure of SAS: MY (kg/d) = 22.7 - 0.52 × SCS, with a confidential interval of 1.92 to 2.84 SCS. Based on this linear model, each unit increment in SCS over 1.92 would decrease MY by 0.52 kg. The maximum predicted MY losses corresponded to 0.48 kg/d, which is equivalent to 146 kg of milk in 305 d of lactation across all breeds. HO cows showed the greatest predicted MY losses on an absolute basis (0.32 kg/d), followed by HO×JE (0.28 kg/d) and JE (0.27 kg/d). However, when expressed as a proportion of 305-d MY, predicted MY losses corresponded to 2.83, 2.00, and 1.10% for JE, HO, and HO×JE, respectively. Predicted MY losses were lower in primiparous (0.17 kg/d) than multiparous (0.40 kg/d), corresponding to 1.27% and 2.59% of total lactation production, respectively. Overall, crossbred cows (HO×JE) resulted in less predicted MY losses during 305-d lactation, and multiparous cows require improved management to reduce SCS and MY losses.