The influence of energy balance, lipolysis and ketogenesis on metabolic adaptation in cows milked twice and three times daily

Krnjaić, Srđan (author), Cincović, M. R. (author), Djoković, Radojica (author), Belić, B. (author), Ježek, Jožica (author), Starič, Jože (author)

Increasing milk production requires increasing milking frequency (MF) from two times daily (2X) to three (3X) or more. High milk production leads to negative energy balance (NEB) and homeorhesis, characterized by lipolysis, ketogenesis, and endocrinological changes. The relationship among energy balance (EB), lipolysis, and ketogenesis with endocrine and metabolic parameters in blood of cows milked 2X and 3X daily was studied. Holstein Friesian cows milked 2X (n = 45) and 3X (n = 45) were analyzed, with approximately 50% of cows in each group in positive EB (PEB) and 50% in NEB. After determining EB, blood samples were collected from all cows and blood serum was analyzed for non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHB), glucose (GLU), cholesterol (CHOL), triglycerides (TGC), total bilirubin (TBIL), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), calcium (Ca), inorganic phosphate (P), total protein (TPROT), albumin (ALB), urea, insulin (INS), T3, T4, and cortisol (CORT), and the RQUICKIBHB index of insulin resistance was calculated. Cows milked 3X in NEB represent a special cluster that partially overlaps with cows milked 2X in NEB and has no contact points with cows in PEB. Cows milked 3X had higher levels of NEFA, BHB, AST, GGT, TBIL, and CORT and lower levels of GLU, Ca, INS, and T4. Cows milked 3X in NEB had higher levels of NEFA, BHB, AST, GGT, TBIL, and CORT and lower levels of GLU, CHOL, TGC, TPROT, P, INS, RQUICKIBHB, and T3 compared with cows milked 2X in NEB and cows in PEB. In cows milked 3X, lipolysis and ketogenesis were much more prominent, and EB levels were lower, implying a pronounced shift in homeorhesis. Metabolic and endocrinology parameters were determined mainly by the values of EB, NEFA, and BHB in cows milked 3X in NEB compared with other categories of cows. The results confirm the peculiarity of metabolic adaptation in cows with increased MF, characterized not only by differences in the concentration of metabolites but also in their interactions.

• Language: English
• Keywords: blood, milk, lactation, cattle
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: VF - Veterinary Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2022
• Number of pages: 17 str.
• Numbering: Vol. 12, no. 11, art. 1090
• PID: 20.500.12556/RUL-142720
• UDC: 636.09:542
• ISSN on article: 2218-1989
• DOI: 10.3390/metabo12111090
• COBISS.SI-ID: 130405635
• Publication date in RUL: 22.11.2022

Record is a part of a journal

• Title: Metabolites
• Shortened title: Metabolites
• Publisher: MDPI
• ISSN: 2218-1989
• COBISS.SI-ID: 523274009

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 22.11.2022

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P4-0092
• Name: Zdravje živali, okolje in varna hrana