Energy requirements for pregnant dairy cows

Anna Luiza Lacerda Sguizzato, Marcos Inacio Marcondes, Jan Dijkstra, Sebastiao De Campos Valadares Filho, Mariana Magalhaes Campos, Fernanda Samarini MacHado, Breno Castro Silva, Polyana Pizzi Rotta*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

2 Citations (Scopus)

Abstract

This study aimed to estimate energy requirements of pregnant Holstein × Gyr cows. Different planes of nutrition were established by two feeding regimens: Ad libitum or maintenance. Sixty-two nonlactating cows with average body weight of 480 ± 10.1 kg and an age of 5 ± 0.5 years were used. Cows were divided into three groups: Pregnant (n = 44), non-pregnant (n = 12), and baseline reference (n = 6). The 56 pregnant and non-pregnant cows were randomly allocated into a feeding regimen: Ad libitum or maintenance. To evaluate the effects of days of pregnancy, pregnant and non-pregnant animals were slaughtered at 140, 200, 240, and 270 days of pregnancy. Energy requirements for maintenance differed between pregnant and non-pregnant cows, thus two equations were developed. Net energy and metabolizable energy requirements for maintenance of non-pregnant cows were 82 kcal/kg empty body weight0.75/day and 132 kcal/kg empty body weight0.75/day, respectively. The efficiency of use of metabolizable energy for maintenance of non-pregnant cows was 62.4%. Net energy and metabolizable energy for maintenance of pregnant cows were 86 kcal/kg empty body weight0.75/day and 137 kcal/kg empty body weight0.75/day, respectively. Efficiency of use of metabolizable energy for maintenance of pregnant cows was 62.5%. The efficiency of use of metabolizable energy for gain was 41.9%. The efficiency of use of metabolizable energy for pregnancy was 14.1%. Furthermore, net energy requirement for pregnancy was different from zero from day 70 of pregnancy onwards. In conclusion, net energy and metabolizable energy requirements for maintenance of non-pregnant cows are different from pregnant cows. Furthermore, we believe that the proposed non-linear equations to estimate net energy requirements for pregnancy are more adequate than current NRC equation, and should be recommended for Holstein × Gyr cows.

Original languageEnglish
Article numbere0235619
JournalPLoS ONE
Volume15
Issue number7 July
DOIs
Publication statusPublished - Jul 2020

Fingerprint Dive into the research topics of 'Energy requirements for pregnant dairy cows'. Together they form a unique fingerprint.

Cite this