INVITED REVIEW: Impact of Maternal Health and Nutrition on the Microbiome and Immune Development of Neonatal Calves

This comprehensive review highlights the intricate interplay between maternal factors and the co-development of the microbiome and immune system in neonatal calves. Based on human and mouse studies, multiple prenatal and postnatal factors influence this process by altering the host-associated microbiomes (gut, respiratory tract, skin), microbial colonization trajectories, and priming of the immune systems (mucosal and systemic). This review emphasizes the importance of early life exposure, highlighting postnatal factors that work in synergy with maternal factors in further finetuning the co-development of the neonatal microbiome and immunity. In cattle, there is a general lack of research to identify the maternal effect on the early colonization process of neonatal calves (gut, respiratory tract) and its impact on the priming of the immune system. Past studies have primarily investigated the maternal effects on the passive transfer of immunity at birth. The co-development process of the microbiome and immune system is vital for lifelong health and production in cattle. Therefore, comprehensive research beyond the traditional focus on passive immunity is an essential step in this endeavor. Calf microbiome research reports the colonization of diverse bacterial communities in newborns, which is affected by the colostrum feeding method immediately after birth. In contrast to human studies reporting a strong link between maternal and infant bacterial communities, there is a lack of evidence to clearly define cow-to-calf transmission in cattle. Maternal exposure has been shown to promote the colonization of beneficial bacteria in neonatal calves. Nonetheless, calf microbiome research lacks links to early development of the immune system. An in-depth understanding of the impact of maternal factors on microbiomes and immunity will improve the management of pregnant cows to raise immune-fit neonatal calves. It is essential to investigate the diverse effects of maternal health conditions and nutrition during pregnancy on the gut microbiome and immunity of neonatal calves through collaboration among researchers from diverse fields such as microbiology, immunology, nutrition, veterinary science, and epidemiology.

Can ultrasonication improve coagulation properties of indigenous and exotic cow milk for dairy product processing?

This study investigates the effects of ultrasonication on milk coagulation properties, focusing on milk from indigenous Thamankaduwa White (TW) and exotic Holstein Friesian (HF) cattle. Milk samples were subjected to ultrasound treatment (20 kHz with a 2 cm probe depth and 60 % amplitude) at three energy densities (504, 612, and 720 J mL-1). Acid-induced gels were formed using a lactic acid starter culture, while rennet-induced gels were produced through enzymatic coagulation. The results demonstrate that ultrasonication significantly enhances the water-holding capacity (WHC) in both gel types, particularly in HF milk treated at 720 J mL-1. Ultrasonication also altered gel hardness, cohesiveness, and microstructure, with TW milk showing more pronounced changes. These include larger and more abundant void spaces in rennet gels and a coarser protein network in acid-induced gels. Ultrasonication offers a practical and efficient method to improve dairy product quality by enhancing WHC, hardness, and cohesiveness while reducing syneresis in milk gels. This technology also promotes the utilization of milk from underutilized indigenous cattle breeds, such as TW, in the dairy industry, contributing to sustainability and addressing industry challenges.