Individual variation in the milk yield response to bovine somatotropin in dairy cows
Contribuinte(s) |
Institute of Biological, Environmental and Rural Sciences |
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Data(s) |
15/12/2008
15/12/2008
01/07/2004
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Resumo |
M. T. Rose, T. E. C. Weekes and P. Rowlinson (2004). Individual variation in the milk yield response to bovine somatotropin in dairy cows. Journal of Dairy Science, 87(7), 2024-2031. Sponsorship: industry RAE2008 The objective was to relate the short-term milk yield response (MYR) following use of exogenous bovine somatotropin (bST) to changes in plasma concentrations of metabolites and hormones. Twenty-four Holstein cows (52 ? 4.1 d postpartum) received daily subcutaneous injections of saline for 1 wk followed by subcutaneous injections of 33 mg/d of bST for 2 wk (Trial 1). The difference in milk yield between wk 1 and 3 for each cow was used to determine the 5 cows with the highest (HR) and 5 with the lowest responses (LR) to bST. These 10 cows were then used in 3 further trials of the same design (Trials 2, 3, and 4, conducted at 122, 181, and 237 ? 7.6 d postpartum, respectively). Blood samples were taken 2 h after the administration of bST on d 1, 3, 5, 15, 17, and 19 of each trial. The HR group had consistently greater MYR to bST than the LR group throughout their lactation. The LR group had a higher milk yield and lower plasma insulin like growth factor-I (IGF-I) concentrations during the saline treatment in all trials. The increase in plasma somatotropin concentrations following injections of bST was greater for the LR group, whereas the difference in plasma IGF-I level between wk 1 and 3 was greater for the HR group. The HR group had lower levels of 3-hydroxy-butyrate and nonesterified fatty acids before bST treatment. Low short-term response to bST was associated with plasma concentrations of hormones and metabolites that indicate negative energy balance, although other factors may be involved. Peer reviewed |
Formato |
8 |
Identificador |
Rose , M T , Weekes , T E C & Rowlinson , P 2004 , ' Individual variation in the milk yield response to bovine somatotropin in dairy cows ' Journal of Dairy Science , vol 87 , no. 7 , pp. 2024-2031 . DOI: 10.3168/jds.S0022-0302(04)70020-X 1525-3198 PURE: 93248 PURE UUID: eeaa9562-62fc-4666-92a4-f4305fb0add8 dspace: 2160/1613 |
Idioma(s) |
eng |
Relação |
Journal of Dairy Science |
Tipo |
/dk/atira/pure/researchoutput/researchoutputtypes/contributiontojournal/article Article (Journal) |
Direitos |