Relação gordura: proteína do leite no primeiro controle leiteiro pós-parto em vacas leiteiras

Ciencia Rural

article

Isabela Fonseca Carrari¹  Jessica Karina Poncheki¹  Milaine Poczynek¹  José Augusto Horst²  Rodrigo de Almeida¹ 

[1] Universidade Federal do Paraná;Associação Paranaense de Criadores de Bovinos da Raça Holandesa

关键词: energy balance;    hyperketonemia;    ketosis;    milk components;    transition period;   

DOI  :  10.1590/0103-8478cr20210690

学科分类：农业科学（综合）

来源: Universidade Federal de Santa Maria * Centro de Ciencias Rurais

【 摘 要 】

This study evaluated milk fat to protein ratio (FPR) in the first test-day after calving of dairy cows in Paraná State. Data from 257,847 first monthly test-days after calving of 114,162 cows were submitted to analysis after the data edition. Procedures MIXED, CORR and STEPWISE from SAS were used in the data analysis. In order to validate FPR, a herd with regular postpartum monitoring of blood β-hydroxybutyrate (BHB) was used to estimate the correlation with FPR. There was a strong positive correlation between FPR and fat content (r = 0.85; P < 0.01) and a weak negative correlation between FPR and protein content (r = - 0.23; P < 0.01). The regression equation that best fitted FPR was 1.1806 + 0.3304*%F - 0.3877*%P (R2 = 0.98), where the variable with the greatest influence was milk fat content (partial R2 = 0.72). Animals of 4th and 5th or more lactations had higher (P < 0.01) FPR, followed by animals of third, first, and second lactations. Jersey cows had higher (P < 0.01) FPR than Holsteins and Brown Swiss animals. Cows milked twice daily had higher (P < 0.01) FPR than animals milked three times daily. There were small positive correlations between milk FPR and blood BHB on days 4, 7 and 12 after calving (0.07, 0.13, and 0.14, respectively). In conclusion, milk fat content was reported to be the most important variable affecting FPR changes, but the milk FPR has limited value to evaluate hyperketonemia incidence during the transition period.

【 授权许可】

Unknown