Graduate Student Literature Review: Implications of transition cow health for reproductive function and targeted reproductive management.

Negative associations of health disorders with reproductive performance, often measured with pregnancy per AI or the risk of pregnancy loss, have been demonstrated extensively. Most studies investigated common clinical diseases but did not include subclinical disorders comprehensively. They often evaluated cows subjected to hormonal synchronization protocols for timed AI, limiting the ability to understand how disease may affect spontaneous reproductive function, which is essential for targeted management programs with selective hormonal intervention.

Progesterone profiles in postpartum dairy cows with inflammatory disorders.

The objective of this prospective cohort study was to determine if progesterone (P4) profiles differed between dairy cows with or without inflammatory disorders early postpartum. A total of 708 cows from 2 commercial herds were enrolled 3 wk before parturition and examined for clinical health disorders (difficult calving, retained placenta, metritis, displaced abomasum, mastitis, or lameness) until 5 wk postpartum. Serum haptoglobin (Hp) was measured in blood at 2 and 6 DIM (range ±2 d); metritis was assessed at 4, 8, 11, and 15 DIM; and purulent vaginal discharge and endometritis (≥6% PMN in endometrial cytology sampled by cytobrush) were assessed at 35 ± 3 DIM.

Effects of systemic or uterine endotoxin challenge in Holstein cows at 5 or 40 days postpartum on clinical responses, uterine and systemic inflammation, and milk yield.

Our objective was to investigate the effects of intravenous (IV) or intrauterine (IU) lipopolysaccharide (LPS) challenge at 5 or 40 d postpartum (DPP) on clinical signs, systemic and uterine inflammation, dry matter intake (DMI), and milk yield (MY). Holstein cows at 5 DPP (n = 23) or at 40 DPP (n = 24) were blocked by parity and randomly assigned to 1 of 3 treatments: (1) IV-LPS (0.0625 μg/kg BW [5 DPP] or 0.

Assessment of systemic inflammation following oral calcium supplementation in healthy postpartum multiparous dairy cows-A randomized controlled trial.

Around parturition, dairy cows inevitably and perhaps necessarily experience some degree of systemic inflammation, but when excessive or dysregulated, it may contribute to health disorders. As immune activation decreases blood Ca, greater extracellular Ca availability may potentiate or sustain inflammation. We hypothesized that in clinically healthy multiparous cows, postpartum administration of supplemental Ca would increase serum concentrations of inflammatory markers.

Associations of postpartum health with progesterone after insemination and endocrine signaling during early pregnancy in dairy cows.

Our objective was to investigate associations of postpartum health with serum progesterone (P4) concentrations after first artificial insemination (AI), expression of interferon-stimulated genes (ISG) in blood leukocytes, and serum pregnancy-associated glycoprotein (PAG) during early pregnancy in dairy cows. In this observational study, Holstein cows (n = 475) from 2 commercial herds were enrolled 3 wk before expected parturition. Body condition score (BCS) and lameness were assessed at enrollment, and total Ca, haptoglobin, and nonesterified fatty acids (NEFA) were measured in serum at 2 and 6 ± 2 d in milk (DIM).