Relative Late Gestational Muscle and Adipose Thickness Reflect the Amount of Mobilization of These Tissues in Periparturient Dairy Cattle

Abstract

Due to insufficient dry matter intake and heightened nutrient requirements in early lactation, periparturient dairy cows mobilize adipose and muscle tissues to bridge energy and amino acid gaps, respectively. Our objective was to evaluate the relationship between the relative muscle thickness of late pregnant cows and their early lactation performance. At 35 d before expected calving (BEC), longissimus dorsi muscle thickness (LDT) was measured in forty-one multiparous Holstein cows via ultrasound. Tissue mobilization was evaluated via ultrasound images of LDT and backfat thickness (BFT) at 21 and 7 d BEC as well as at 0, 10, 30, and 60 DIM. Plasma concentrations of 3-methylhistidine (3-MH), creatinine (CRE), non-esterified fatty acids (NEFA), and β-hydroxybutyrate (BHB) were evaluated weekly. Milk yield and milk component data were collected through 60 DIM. Cattle were assigned post hoc to high-muscle (HM; n = 20; LDT > 4.49 cm) or low-muscle (LM; n = 21; ≤4.37 cm) groups, with mean LDT at 35 d BEC greater in HM (5.05 ± 0.49) than in LM (3.52 ± 0.65) animals. Between 35 and 21 d BEC, LM cows gained LDT, whereas HM cows gained BFT. HM cows mobilized more muscle from 21 d BEC to 30 DIM, as reflected by a greater loss of LDT, greater 3-MH concentrations (532 vs. 438 ± 30 ng/mL), and a greater 3-MH:CRE ratio (0.164 vs. 0.131 ± 0.008) in the first three weeks postpartum. The LDT and BFT at 21 d BEC were related to the amount of respective tissue mobilized through 30 DIM (R2 = 0.37 and 0.88, respectively). Although calves born to HM cattle were larger (45.2 vs. 41.8 ± 0.7 kg), HM cows produced less milk (38.8 vs. 41.6 ± 0.8 kg/d) with a tendency towards higher fat content (4.33 vs. 4.05 ± 0.12%), likely related to the mobilization of more backfat from 0 to 60 DIM (1.78 vs. 0.68 ± 0.34 mm), compared to LM cattle. These findings suggest that a cow’s metabolic status, as measured by LDT and BFT prepartum, may influence the metabolic strategy the animal uses to meet energy and amino acid requirements in late gestation and early lactation.

Impact of Exposure to Chronic Light–Dark Phase Shifting Circadian Rhythm Disruption on Muscle Proteome in Periparturient Dairy Cows

“…A graphical schematic of the experimental design is shown in Figure 1. At 21 days BEC and 21 days PP, longissimus dorsi biopsies were performed at approximately 0700 h. The longissimus dorsi muscle was chosen, as changes in its depth and composition in relation to nutritional manipulations and physiological states of animal have been well characterized [12][13][14]. Biopsies taken at 21 days BEC were collected between the 9th and 12th intercostal spaces on the left side of the animal.…”

Improving adaptation to lactation: nutrition and management strategies for periparturient dairy cattle

“…A higher BCS at calving will result in a larger BCS decrease in early lactation, simply because the potential to lose BCS is larger compared with cows with a low BCS at calving. Cows with higher backfat thickness precalving mobilized a greater amount of backfat during the first weeks of lactation (Van der Drift et al, 2012;McCabe et al, 2021). For three of the 34 cows in this study, extreme mobilization resulted in high NEFA concentrations and severe hyperketonemia; for the other 31 cows, the degree of hyperketonemia did not correlate with the amount of fat mobilization ( Van der Drift et al, 2012).…”