Bovine Respiratory Disease (BRD) in Post-Weaning Calves with Different Prevention Strategies and the Impact on Performance and Health Status.

Our study aimed to compare Bovine Respiratory Disease (BRD) morbidity, mortality, and growth in dairy and dairy beef cross-bred calves during the commingle period, 81-120 days of age, using two different BRD prevention strategies. The calves (n = 1799) were randomly assigned into groups: (1) Control (CON; received no vaccine or metaphylaxis); (2) Tulathromycin metaphylaxis (TUL; Increxxa, Elanco Animal Health Inc., Greenfield, IN, USA); and (3) vaccine (VACC; Nuplura PH, Elanco Animal Health Inc.

Effects of Receiving Two Initial Feedings of Colostrum on the Average Daily Gain and Health of Pre-Weaning Group Housed Holstein Heifer Calves.

We studied the effect on average daily gain (ADG) and health of an additional colostrum feeding to Holstein dairy heifers 12-16 h after the first colostrum feeding, provided within 2 h of birth. Calves (n = 190) with an average birth weight of 38.8 kg (29.

Blood β-hydroxybutyrate concentrations and early lactation management strategies on pasture-based dairy farms in Colombia.

The increasing global demand for food requires sustainable solutions to close the gap in agricultural yield between industrialized and non-industrialized countries. Our objectives in this cross-sectional study were to: 1) characterize farm populations, milk yield, and early lactation management strategies of dairy cows in three different regions of Colombia, and 2) determine the association of these management strategies with blood β-hydroxybutyrate (BHB) concentrations in the first 42 days in milk (DIM). Dairy herds (n = 56) in the Antioquia, Caldas, and Cundinamarca regions of Colombia were visited once from May through July 2018.

Longitudinal Phenotypes Improve Genotype Association for Hyperketonemia in Dairy Cattle.

The objective of our study was to identify genomic regions associated with varying concentrations of non-esterified fatty acid (NEFA), β-hydroxybutyrate (BHB), and the development of hyperketonemia (HYK) in longitudinally sampled Holstein dairy cows. Our study population consisted of 147 multiparous cows intensively characterized by serial NEFA and BHB concentrations. To identify individuals with contrasting combinations in longitudinal BHB and NEFA concentrations, phenotypes were established using incremental area under the curve (AUC) and categorized as follows: Group (1) high NEFA and high BHB, group (2) low NEFA and high BHB), group (3) low NEFA and low BHB, and group (4) high NEFA and low BHB.

Udder and teat conformational risk factors for elevated somatic cell count and clinical mastitis in New York Holsteins.

Our primary objective was to identify udder and teat conformational risk factors associated with the occurrence of elevated somatic cell count (SCC) and clinical mastitis using a prospective cohort study design with careful assessment of exposure and disease outcomes. Mastitis prevalence was evaluated by parity across 6 sampling periods representing key physiological transitions during lactation: 0-1 day in milk (DIM), 3-5 DIM, 10-14 DIM, 50-60 DIM, 90-110 DIM, and 210-230 DIM. Cows were scored for front and rear teat length, width, end shape, and placement, fore udder attachment, udder cleft, udder depth, rear udder height, and rear udder width.

The effect of the transition period and postpartum body weight loss on macrophage infiltrates in bovine subcutaneous adipose tissue.

The transition period in dairy cattle is characterized by a rapid increase in metabolic demands due to the onset of lactation in parallel with a voluntary drop in dry matter intake, which slowly increases compared with the rapidly increasing milk production. The resulting deficit in energy intake is largely met by lipolysis of adipose tissue stores liberating nonesterified fatty acids (NEFA) as energy substrates to support milk production and for the synthesis of milk fat. Previous work in cattle and other species has documented an increase in adipose tissue macrophages (ATM) during periods of feed restriction and lipolysis; however, alterations in ATM during the transition period have only recently received interest because of the role that adipose tissue remodeling and inflammation may play during this time.