Abstract #T270
Section: Lactation Biology
Session: Lactation Biology II
Format: Poster
Day/Time: Tuesday 7:30 AM–9:30 AM
Location: Gatlin Ballroom
Session: Lactation Biology II
Format: Poster
Day/Time: Tuesday 7:30 AM–9:30 AM
Location: Gatlin Ballroom
# T270
Lactation performance of dairy cows milked 3 times per day and supplemented with two different formulations of bovine somatotropin.
Jozivaldo P. G. Morais*1, Andressa P. da S. Cruz1, Natalia S. Minami1, Luiz P. Veronese1, Tiago A. Del Valle1, Simone D. Sartorio1, 1Universidade Federal de São Carlos, UFSCAR, Araras, SP, Brazil.
Key Words: milk composition, milk yield, recombinant bST
Lactation performance of dairy cows milked 3 times per day and supplemented with two different formulations of bovine somatotropin.
Jozivaldo P. G. Morais*1, Andressa P. da S. Cruz1, Natalia S. Minami1, Luiz P. Veronese1, Tiago A. Del Valle1, Simone D. Sartorio1, 1Universidade Federal de São Carlos, UFSCAR, Araras, SP, Brazil.
The aim of this randomized field study was to evaluate the lactation performance of dairy cows supplemented with 2 different 500-mg bovine somatotropin (bST) formulations. Sixty Holstein cows were allocated to a control, 90 Holstein cows to a somatotropin fast release formulation (FR-bST, Boostin-S, LG Life Science), and 90 Holstein cows to a somatotropin slow release formulation (SR-bST, Lactotropin, Elanco Animal Health). Treatments (TRT) were delivered every 14 d starting at 57–70 d post calving until the end of lactation, or 17 injections. Before TRT assignment, animals were paired by milk yield, lactation number, and randomly assigned to one of the 3 TRT. Evaluated parameters were milk production, milk protein, milk fat, milk SCC, and BCS. Somatotropin treatment increased milk yield (P < 0.001). SR-bST treated cows, yielded 1.6 kg/day more milk than FR-bST treated cows (P = 0.008). Somatotropin increased milk protein % (P = 0.002), decreased BCS (P < 0.001), and had no effect on milk fat % (P = 0.120) and SCC (P = 0.964). Results are shown in Table 1.
Table 1. Production variables of cows milked 3 times per day without bST and with 2 different bST formulations1
1FR-bST = Boostin-S, LG Life Science; SR-bST = Lactotropin, Elanco Animal Health. Starting on d 63 bovine somatotropin was administered at 14-d intervals to cows on the groups to receive bst.
2C1 = control vs. bST; C2 = FR-bST vs. SR-bST.
Item | Treatment | SEM | P-value42 | |||
No bst | FR-bst | SR-bst | C1 | C2 | ||
Pre-TRT period | ||||||
Milk, kg/d | 40.04 | 40.38 | 39.96 | 0.464 | 0.880 | 0.635 |
Fat, % | 3.36 | 3.17 | 3.28 | 0.063 | 0.349 | 0.469 |
Protein, % | 2.68 | 2.73 | 2.69 | 0.014 | 0.448 | 0.216 |
SCC, ×103/mL | 38.74 | 39.99 | 40.92 | 2.459 | 0.350 | 0.885 |
BCS | 2.94 | 2.94 | 2.95 | 0.016 | 0.851 | 0.975 |
TRT period | ||||||
Milk, kg/d | 34.63 | 38.03 | 39.60 | 0.131 | <0.001 | 0.008 |
Fat, % | 3.18 | 3.06 | 3.10 | 0.001 | 0.120 | 0.576 |
Protein, % | 3.01 | 3.11 | 3.07 | 0.001 | 0.002 | 0.086 |
SCC, ×103/mL | 242.6 | 181.1 | 166.8 | 11.50 | 0.964 | 0.865 |
BCS | 3.04 | 2.95 | 2.93 | 0.003 | <0.001 | 0.263 |
Key Words: milk composition, milk yield, recombinant bST