Annual Review of Animal Biosciences最新文献

Rodents have been the primary model for mammalian nutritional physiology for decades. Despite an extensive body of literature, controversies remain around the effects of specific nutrients and total energy intake on several aspects of nutritional biology, even in this well-studied model. One approach that is helping to bring clarity to the field is the geometric framework for nutrition (GFN). The GFN is a multidimensional paradigm that can be used to conceptualize nutrition and nutritional effects, design experiments, and interpret results. To date, more than 30 publications have applied the GFN to data from rodent models of nutrition. Here we review the major conclusions from these studies. We pay particular attention to the effects of macronutrients on satiety, glucose metabolism, lifespan and the biology of aging, reproductive function, immune function, and the microbiome. We finish by highlighting several knowledge gaps that became evident upon reviewing this literature.

This comprehensive review explores the complex processes of reproduction, pregnancy establishment, and pregnancy diagnostic methods in cattle, sheep, goats, swine, horses, and camelids. It provides an overview of the history of pregnancy detection and an in-depth exploration of the physiology of pregnancy in livestock. The detection of conceptus tissue and fluids, conceptus-produced hormones, and maternal responses to conceptus signals, crucial for pregnancy diagnosis, are also discussed in detail, as are emerging methods for pregnancy diagnosis in livestock species. Overall, this review emphasizes the direct impact of pregnancy diagnosis and efficient pregnancy management for profitability of livestock enterprises.

Studies examining the evolution of genomes have focused mainly on sequence conservation. However, the inner working of a cell implies tightly regulated crosstalk between complex gene networks controlled by small dispersed regulatory elements of physically contacting DNA regions. How these different levels of chromatin organization crosstalk in different species underpins the potential for genome evolutionary plasticity. We review the evolution of chromatin organization across the Animal Tree of Life. We introduce general aspects of the mode and tempo of genome evolution to later explore the multiple layers of genome organization. We argue that both genome and chromosome size modulate patterns of chromatin folding and that chromatin interactions facilitate the formation of lineage-specific chromosomal reorganizations, especially in germ cells. Overall, analyzing the mechanistic forces involved in the maintenance of chromatin structure and function of the germ line is critical for understanding genome evolution, maintenance, and inheritance.

Nutrition is a complex and contested area in biomedicine, which requires diverse evidence sources. Nonhuman primate models are considered an important biomedical research tool because of their biological similarities to humans, but they are typically used with little explicit consideration of their ecology and evolution. Using the rhesus macaque (RM), we consider the potential of nutritional ecology for enriching the use of primates as models for human nutrition. We introduce some relevant aspects of RM evolutionary and social ecology and discuss two examples where they have been used in biomedical research: obesity and aging. We next consider how insights from nutritional ecology can help inform and direct the use of RM as a biomedical model. We conclude by illustrating how conceptual tools might inform the use of RM as a model for human nutrition and extracting insights from RM that might be relevant to broader theoretical considerations around animal model systems.

Porcine cancer models offer a valuable platform for evaluating interventions such as devices, surgeries, and locoregional therapies, which are often challenging to test in mouse models. In addition to size and anatomical similarities with humans, pigs share greater similarities in genetics, immunity, drug metabolism, and metabolic rate with humans as compared to mouse models, increasing their translational relevance. This review focuses on the Oncopig Cancer Model, a genetically engineered porcine model designed to recapitulate human cancer. Harboring a transgenic cassette that expresses oncogenic mutant KRAS and TP53 under control of a Cre-Lox system, the Oncopig allows temporal and spatial control of tumor induction. Its versatility has enabled the development of diverse cancer models including liver, pancreatic, lung, and bladder cancer. Serving as a clinically relevant model for human cancer, the Oncopig addresses unmet clinical needs and holds immense promise for advancing preclinical cancer research and therapeutic development.

Viviparity (live birth) represents a significant evolutionary innovation that has emerged in hundreds of lineages of invertebrate and vertebrate animals. The evolution of this trait from the ancestral state of egg laying has involved complex morphological, behavioral, physiological, and genetic changes, which enable internal development of embryos within the female reproductive tract. Comparable changes have also occurred in oviparous, brooding species that carry developing embryos in locations other than the female reproductive tract. This review explores the taxonomic distribution of vertebrate viviparity and brooding (collectively termed pregnancy), discusses the adaptations associated with internal incubation, and examines hypotheses surrounding the evolution of pregnancy in different lineages. Understanding the mechanisms that have led to the emergence of this trait can illuminate questions about the evolution of reproductive complexity and the processes that led to the emergence of evolutionary innovations that have shaped the remarkable diversity of Earth's fauna.

With the burgeoning human population, climate change, and expansion of poultry production in hot climates, it is imperative to aid global food security by enhancing the resilience of thermally challenged poultry. As a complement to management approaches used to mitigate heat stress, we give selected examples of recent studies on heat stress in poultry using various omics technologies. An integrated analysis of positional and functional candidate genes is provided, highlighting the most prominent pathways involved in the heat stress response. We finish by discussing efficient strategies to enhance thermal tolerance of poultry by genomics approaches, advocating for preservation of biodiversity that may provide beneficial allelic variation, and identifying current and future challenges in producing climate-resilient poultry.

Metabolic stress conditions are often characterized by upregulated lipolysis and subsequently increased serum free fatty acid (FFA) concentrations, leading to the uptake of FFAs by non-adipose tissues and impairment of their function. This phenomenon is known as lipotoxicity. The increased serum FFA concentrations are reflected in the ovarian follicular fluid, which can have harmful effects on oocyte development. Several studies using in vitro and in vivo mammalian models showed that altered oocyte metabolism, increased oxidative stress, and mitochondrial dysfunction are crucial mechanisms underlying this detrimental impact. Ultimately, this can impair offspring health through the persistence of defective mitochondria in the embryo, hampering epigenetic reprogramming and early development. In vitro and in vivo treatments to enhance oocyte mitochondrial function are increasingly being developed. This can help to improve pregnancy rates and safeguard offspring health in metabolically compromised individuals.

A love of science and animals, perseverance, and happenstance propelled my career in veterinary virology and immunology. I have focused on deadly enteric and respiratory viral infections in neonatal livestock and humans with an aim to understand their prevalence, pathogenesis, interspecies transmission, and immunity and develop vaccines. Research on animal coronaviruses (CoVs), including their broad interspecies transmission, provided a foundation to understand emerging zoonotic fatal human respiratory CoVs [severe acute respiratory syndrome, Middle East respiratory syndrome, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)] and reverse zoonosis of SARS-CoV-2 to animals. A highlight of my early research was the discovery of the gut-mammary gland-sIgA axis, documenting a common mucosal immune system. The latter remains pivotal to designing maternal vaccines for passive immunity in neonates. Our discovery and innovative cell propagation of fastidious human and animal rotaviruses and caliciviruses and their infectivity in germ-free animals has provided cell-adapted and animal disease models for ongoing virologic and immunologic investigations and vaccines. Nevertheless, besides the research discoveries, my lasting legacy remains the outstanding mentees who have enriched my science and my life.