NUTRITIONAL CHARACTERISTICS OF THE DAIRY COW DURING EARLY GESTATION AND SUBSEQUENT GROWTH AND CARDIAC MEASUREMENTS OF HER OFFSPRING

The objective was to determine whether maternal nutritional status and milk production during early gestation influenced or were correlated with parameters of the calf at birth and at 1 month of age. From parturition until 90 days pregnant, blood samples were collected every 14 days in dairy cows and plasma was assayed for concentrations of glucose and β-Hydroxybutyrate (BHBA). Calves (n = 39) born from these cows were measured for blood pressure and size characteristics as well as carotid artery hemodynamics measured via Doppler ultrasonography Pulsatility Index (PI) and Resistance Index (RI). Several values were then calculated to assess the cardiovascular health of the calf. The GLM and CORR procedures of SAS were used to analyze data and significance was determined when p≤0.05 and tendencies were discussed when p>0.05 and ≤0.10. In calves at birth, mean milk production of dams during early gestation was positively correlated with heart girth. Length of gestation was positively correlated with heart girth of calves at birth and at 1 month of age. Mean concentration of glucose in dams was positively correlated with wither height in calves at 1 month of age. Length of gestation was negatively correlated with RI in calves at 1 month of age. Milk production in the dam was positively correlated with hip and wither height and PI but negatively correlated with mean arterial pressure in 1 month old calves. At birth, twins weighed less than singletons and females had an increased heart rate compared to males. At 1 month of age, size parameters and mean blood flow differed between singletons and twins. Males had lesser blood velocity but greater area of the carotid artery compared to females. These data lead to speculation that early gestational environment may impact growth and hemodynamic parameters in calves.