Nutritional management in rangeland beef cattle systems prioritises optimal body condition scores at calving for improved fertility and reproductive success. However, this focus often overlooks short-term dietary deficiencies before calving, which can lead to adverse outcomes for neonatal calves. This review explores the effects of beef cow malnutrition during the periparturient period on colostrum production, lactation onset, and passive immunity transfer to calves. Additionally, it discusses the long-term impact of such malnutrition on the offspring. By understanding how nutritional interventions affect the transition from gestation to lactation, it becomes possible to enhance calf health and survival in arid tropical environments. Commonly occurring short-term dietary restrictions, particularly protein deficiencies, can disrupt the hormonal equilibrium, resulting in reduced colostrum volume and quality, hindering calf growth and increasing mortality risks. Furthermore, dietary restrictions during this period affect critical physiological processes such as mammary gland blood flow and fetal small-intestine development. The review explores how these constraints influence colostrum production and immunoglobulin absorption by neonatal calves. Additionally, it highlights the significance of addressing other common nutrient deficiencies such as phosphorus and water and investigates the potential benefits of supplementing microbial products to enhance rumen function and protect cows from inflammation. Ultimately, addressing malnutrition during pregnancy is essential to prevent negative impacts on offspring performance, including alterations in carcass composition and muscle marbling. Consequently, cattle producers who aim for superior muscle marbling in the carcass by using costly genetics should give priority to enhancing nutritional programs for late-pregnant cows. In conclusion, a comprehensive understanding of the effects of malnutrition during the periparturient period on colostrum production, passive immunity transfer, and overall calf health is crucial for developing effective nutritional interventions that improve colostrum production, passive immunity transfer, and overall calf health in rangeland beef cattle systems.

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weeks gestation provided a blood sample and completed a food frequency and sociodemographic/health behavior questionnaire. Both serum (n = 1825) and red blood cell (n = 887) folate were analyzed using immunoassay techniques. Dietary folate was poorly correlated with serum (r = -0.08) and red blood cell (-0.05) folate, even after accounting for supplement use. Serum folate was moderately associated with red blood cell folate r = 0.43. The lowest tertile of serum folate was consistently associated with preterm birth even after adjustment for supplement use, smoking, and pregravid BMI (AOR = 2.0, 95% CI = 1.4, 2.8), with a stronger association among non-supplement users (AOR = 2.9, 95% CI = 1.2, 7.3). There was no association with dietary intake. The unadjusted odds ratio for the lowest tertile of red cell folate was near the null for the entire sample as well as for supplement users, but was 1.56 (95% CI = 0.8, 2.8) among non-supplement users. The adjusted odds ratio was 1.24 (95% CI = 0.84, 1.8) for the entire sample, which did not change much after stratification by supplement use (AOR = 1.24 supplement vs. 1.39 non-supplement users). Serum folate was associated with a preterm birth when measured in the second trimester of pregnancy, but the discordant results between the short (serum) and long (red blood cell) term markers of folate status and preterm birth warrant further investigation.Young maternal age and poor pregnancy outcomes: revisiting the association