Association of Body Condition Score and Score Change during the Late Dry Period on Temporal Patterns of Beta-Hydroxybutyrate Concentration and Milk Yield and Composition in Early Lactation of Dairy Cows

Abstract

Monitoring the body condition score (BCS) of dairy cows is a management strategy that can assist dairy producers in decision-making. The BCS and its variations reflect the level of body fat reserves and fat mobilization throughout the different stages of lactation. Cows that mobilize excessive amounts of fat reserves in response to the increased energy requirements of the transition period are more likely to have higher beta-hydroxybutyrate (BHB) concentration in blood, leading to a higher incidence of hyperketonemia postpartum. In this study, our main objective was to evaluate how both BCS (at 21 d prior to the expected calving date, −21 BCS) and change in BCS during the late dry period (−21 d to calving, ∆BCS) are associated with temporal patterns of blood BHB concentrations during the first two weeks of lactation. Our secondary objective was to characterize the relationship between the change in BCS in the late dry period, and milk yield and milk composition in the first milk test postpartum. In this retrospective cohort study, we assessed BCS at 21 (±3) days before the expected calving date and within three days after calving. Blood BHB concentration was measured at days 3 (±1), 7 (±1), and 14 (±1) postpartum. Hyperketonemia (HYK) was defined as blood BHB ≥ 1.2 mmol/L. To evaluate how −21 BCS and ∆BCS during the late dry period were associated with BHB in early lactation, linear mixed-effects regression models with an unstructured covariate matrix were performed. The association between ∆BCS and incidence of postpartum HYK were determined using a multivariable log-binomial model. A linear regression model was used to evaluate the association between ∆BCS and milk yield and milk composition in the first monthly test-day. Covariates used for model adjustment include parity, season, and baseline BCS. We observed that cows with BCS ≥ 4.0 at 21 d before their expected calving date had the highest BHB concentration postpartum, but no evidence that BCS ≥ 4.0 at 21 d was associated with fluctuations of BHB over time. Cows that experienced a large BCS loss (larger than 0.5 units) during the late dry period had a 61% (95% CI: 1.04, 2.50) higher risk of developing HYK in early lactation and had higher BHB concentrations during early lactation compared with cows with no ∆BCS prepartum. These associations were observed independently of the BCS at −21 d prepartum (baseline). In addition, cows that lost more than 0.5 BCS unit in the late dry period produced 3.3 kg less milk (95% CI: −7.06, 0.45) at the first milk test compared to cows that had no ∆BCS during the late dry period. No evidence of an association between −21 BCS and ∆BCS in the late dry period and milk composition was observed in our study. These results suggest that dynamic measures of BCS during the late dry period, such as ∆BCS, are better at evaluating blood BHB patterns in early lactation than BCS measured at a single time point. Cows with larger BCS loss during the late dry period and with greater parity are more likely to have higher concentrations of blood BHB postpartum, with the highest concentrations reported at 7 d post-calving.

Risk factors for ultrasound‐diagnosed endometritis and its impact on fertility in Scottish dairy cattle herds

“…Low BCS in the prepartum period has been directly linked to the development of RTD 38 . Excessive BCS loss from the dry period to early lactation has been associated with poor health in early lactation, including an increased incidence of metritis, RFM and hyperketonaemia 39–41 . Limitations in data collection meant that loss of BCS between dry off and lactation was not analysed in the present study.…”

“…38 Excessive BCS loss from the dry period to early lactation has been associated with poor health in early lactation, including an increased incidence of metritis, RFM and hyperketonaemia. [39][40][41] Limitations in data collection meant that loss of BCS between dry off and lactation was not analysed in the present study. Changes between body condition at calving and 43 ± 3 DIM were not associated with UDE, indicating that these measures of body condition alone are not useful when considering the risk factors for UDE.…”

Antioxidant monoammonium glycyrrhizinate alleviates damage from oxidative stress in perinatal cows

“…Perinatal cows often encounter oxidative stress, which may cause host immune and inflammatory dysfunction, thus, endangering the health and reducing milk production of dairy cows (Bendich, 1993; Sordillo & Aitken, 2009). BCS is a recognised tool for evaluating body fat mobilisation of dairy cows (Rodriguez et al, 2021). It has been reported that the BCS of dairy cows was decreased during the perinatal period (Y. Wang et al, 2019).…”

Relationship of Body Condition Score at Calving with Reproductive Performance, some Blood Metabolites and some Pathological Conditions in Holstein Cows

“…A study revealed a positive association between the body condition at calving and an increase in the concentration of BHB during early lactation [60,61]. [3] also found an increase in the concentration of BHB in the first 14 days of lactation in milk cows with body condition ≥ 4 points compared to cows with body condition ≤ 3.75 points according to 1-5 point scal at day 21 of the expected date of calving. After calving, there are two correlated factors: decreased feed intake and increased fat mobilization.…”

“…Most of the high-production milk cows suffer from a state of negative energy balance, especially during early lactation, because the energy requirements to maintain the functions of body tissues and production exceed what the cows consume of energy, and with increased production, the metabolic rate rises, which is reinforced by an increase in metabolic stress, and then followed by a decline in reproductive characteristics And health status [1,2,3,4], and mobilizing the body's energy reserves during early production enables the cow to bridge the gap between dietary energy intake and its deficiency at production (5). The changes in energy reserves have a significant impact on the health condition and reproductive performance in milk cows, so here it is clear that it is necessary to use administrative means to monitor the energy reserves in the cow's body.…”