Genetic parameter estimation for milk β-hydroxybutyrate and acetone in early lactation and its association with fat to protein ratio and energy balance in Korean Holstein cattle

Abstract

ObjectiveThe objective of this study was to estimate the genetic parameters for milk β-hydroxybutyrate (BHBA), acetone (Ac), fat protein ratio (FPR), and energy balance (EB) using milk test day records and investigate the effect of early lactation FPR and EB on milk ketone body concentrations.MethodsTotal 262,940 test-day records collected from Korea Animal Improvement Association during the period of 2012 to 2016 were used in this study. BHBA and Ac concentrations in milk were measured by Fourier transform infrared spectroscopy (FTIR). FPR values were obtained using test day records of fat and protein percentage. EB was calculated using previously developed equation based on parity, lactation week, and milk composition data. Genetic parameters were estimated by restricted maximum likelihood procedure based on repeatability model using Wombat program.ResultsElevated milk BHBA and Ac concentrations were observed during the early lactation under the negative energy balance. Milk FPR tends to decrease with the decreasing ketone body concentrations. Heritability estimates for milk BHBA, Ac, EB, and FPR ranged from 0.09 to 0.14, 0.23 to 0.31, 0.19 to 0.52, and 0.16 to 0.42 respectively at parity 1, 2, 3, and 4. The overall heritability for BHBA, Ac, EB and FPR were 0.29, 0.32, 0.58, and 0.38 respectively. A common pattern was observed in heritability of EB and FPR along with parities.ConclusionFPR and EB can be suggested as potential predictors for risk of hyperketonemia. The heritability estimates of milk BHBA, Ac, EB, and FPR indicate that the selective breeding may contribute to maintaining the milk ketone bodies at optimum level during early lactation.

Predictive ability of host genetics and rumen microbiome for subclinical ketosis

“…An exception to these reports was a higher heritability estimate reported by Buitenhuis et al (2013) for milk BHB (h 2 = 0.87) using cows that were all sampled in mid-lactation. The heritability value estimated in our study for milk acetone (h 2 = 0.10) was generally lower than estimates from previous studies, which were in the range of 0.22 to 0.31 (Lee et al., 2016; Ranaraja et al, 2018). Generally, heritability estimates for milk concentration of ketone bodies might vary between studies depending on stages of lactation of sampled cows.…”

Investigation of β‐hydroxybutyrate in early lactation of Simmental cows: Genetic parameters and genomic predictions

“…Koeck et al (2014) reported h 2 values ranging from 0.14 to 0.29 for Canadian Holsteins. Similar h 2 was reported for Korean Holsteins (Ranaraja et al 2018) ranging from 0.14 to 0.09 in the first and fourth parity, respectively. Weigel et al (2017) estimated heritability for three BHB phenotypes (maximum concentration, square root scale, binary scale) in Holsteins using both BLUP and ssGBLUP (0.06-0.09).…”

Symposium review: Big data, big predictions: Utilizing milk Fourier-transform infrared and genomics to improve hyperketonemia management

“…Milk ketone body concentration, predicted from FTIR and collected during routine DHI testing, has been proposed as an indicator trait for HYK susceptibility. These traits are heritable, with milk acetone heritability ranging from 0.10 to 0.28 (van der Drift et al, 2012a;Ranaraja et al, 2018) and milk BHB heritability ranging from 0.067 to 0.19 (van der Drift et al, 2012a;Koeck et al, 2014;Jamrozik et al, 2016;Ranaraja et al, 2018). Genetic correlations between clinical HYK records and FTIR-predicted ketone bod-ies are moderate, ranging from 0.25 to 0.48 (Koeck et al, 2014;Jamrozik et al, 2016).…”