Annual Review of Animal Biosciences最新文献

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.

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.

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.

Challenges in livestock production in developing countries are often linked to a high disease prevalence and may be related to poor husbandry, feeding, and nutrition practices, as well as to inadequate access to preventive veterinary care. Structural barriers including chronic poverty, gender roles, inadequate supply chains, and limitations in surveillance infrastructure further complicate progress. Despite many challenges, the livestock sector substantially contributes to agricultural GDP, and reducing livestock disease prevalence is a goal for many countries. One Health initiatives that work across disciplines and sectors to reduce livestock diseases are underway around the world and use integrated approaches that consider the connections between humans, animals, and their shared environments. The growing recognition of the role livestock play in sustainability and livelihoods, as well as their involvement in zoonotic disease transmission and global health security, has highlighted the need for disease reduction strategies as described in this review.

There are plenty of reasons to believe that parasite populations will respond to biodiversity loss, warming, pollution, and other forms of global change. But will global change enhance transmission, increasing the incidence of troublesome parasites that put people, livestock, and wildlife at risk? Or will parasite species decline in abundance-or even become extinct-suggesting trouble on the horizon for parasite biodiversity? Here, I explain why answers have thus far eluded us and suggest new lines of research that would advance the field. Data collected to date suggest that parasites can respond to global change with increases or decreases in abundance, depending on the driver and the parasite. The future will certainly bring outbreaks of some parasites, and these should be addressed to protect human and ecosystem health. But troublesome parasites should not consume all of our research effort, because this changing world contains many parasite species that are in trouble.

The decline in human reproductive and metabolic health over the past 50 years is associated with exposure to complex mixtures of anthropogenic environmental chemicals (ECs). Real-life EC exposure has varied over time and differs across geographical locations. Health-related issues include declining sperm quality, advanced puberty onset, premature ovarian insufficiency, cancer, obesity, and metabolic syndrome. Prospective animal studies with individual and limited EC mixtures support these observations and provide a means to investigate underlying physiological and molecular mechanisms. The greatest impacts of EC exposure are through programming of the developing embryo and/or fetus, with additional placental effects reported in eutherian mammals. Single-chemical effects and mechanistic studies, including transgenerational epigenetic inheritance, have been undertaken in rodents. Important translational models of human exposure are provided by companion animals, due to a shared environment, and sheep exposed to anthropogenic chemical mixtures present in pastures treated with sewage sludge (biosolids). Future animal research should prioritize EC mixtures that extend beyond a single developmental stage and/or generation. This would provide a more representative platform to investigate genetic and underlying mechanisms that explain sexually dimorphic and individual effects that could facilitate mitigation strategies.

Immune modulation in animal agriculture has been of research interest for several decades, yet only a few immunomodulators have received regulatory approval in the United States and around the world. In this review, we summarize market and regulatory environments impacting commercial development of immunomodulators for use in livestock and poultry. In the United States, very few immunomodulators have received regulatory approval for use in livestock by either the US Department of Agriculture Center for Veterinary Biologics or the Food and Drug Administration (FDA). To date, only one immunomodulator has received FDA approval, and an extensive body of peer-reviewed literature is available regarding the basis for its use and health benefits. We present a more thorough review of the history and impact of this immune restorative. Finally, we discuss the interaction of immunomodulators on health, metabolism, and other factors impacting the future of immune modulation in livestock.