Hasil untuk "Animal culture"

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S2 Open Access 2020
Human organoids: model systems for human biology and medicine

Jihoon Kim, B. Koo, J. Knoblich

The historical reliance of biological research on the use of animal models has sometimes made it challenging to address questions that are specific to the understanding of human biology and disease. But with the advent of human organoids — which are stem cell-derived 3D culture systems — it is now possible to re-create the architecture and physiology of human organs in remarkable detail. Human organoids provide unique opportunities for the study of human disease and complement animal models. Human organoids have been used to study infectious diseases, genetic disorders and cancers through the genetic engineering of human stem cells, as well as directly when organoids are generated from patient biopsy samples. This Review discusses the applications, advantages and disadvantages of human organoids as models of development and disease and outlines the challenges that have to be overcome for organoids to be able to substantially reduce the need for animal experiments. Human organoids are valuable models for the study of development and disease and for drug discovery, thus complementing traditional animal models. The generation of organoids from patient biopsy samples has enabled researchers to study, for example, infectious diseases, genetic disorders and cancers. This Review discusses the advantages, disadvantages and future challenges of the use of organoids as models for human biology.

1655 sitasi en Medicine, Biology
S2 Open Access 2012
The effect of nanoparticle size, shape, and surface chemistry on biological systems.

Alexandre Albanese, P. S. Tang, W. Chan

An understanding of the interactions between nanoparticles and biological systems is of significant interest. Studies aimed at correlating the properties of nanomaterials such as size, shape, chemical functionality, surface charge, and composition with biomolecular signaling, biological kinetics, transportation, and toxicity in both cell culture and animal experiments are under way. These fundamental studies will provide a foundation for engineering the next generation of nanoscale devices. Here, we provide rationales for these studies, review the current progress in studies of the interactions of nanomaterials with biological systems, and provide a perspective on the long-term implications of these findings.

3435 sitasi en Medicine, Chemistry
S2 Open Access 2010
Directed differentiation of human pluripotent stem cells into intestinal tissue in vitro

J. Spence, C. Mayhew, S. Rankin et al.

Studies in embryonic development have guided successful efforts to direct the differentiation of human embryonic and induced pluripotent stem cells (PSCs) into specific organ cell types in vitro. For example, human PSCs have been differentiated into monolayer cultures of liver hepatocytes and pancreatic endocrine cells that have therapeutic efficacy in animal models of liver disease and diabetes, respectively. However, the generation of complex three-dimensional organ tissues in vitro remains a major challenge for translational studies. Here we establish a robust and efficient process to direct the differentiation of human PSCs into intestinal tissue in vitro using a temporal series of growth factor manipulations to mimic embryonic intestinal development. This involved activin-induced definitive endoderm formation, FGF/Wnt-induced posterior endoderm pattering, hindgut specification and morphogenesis, and a pro-intestinal culture system to promote intestinal growth, morphogenesis and cytodifferentiation. The resulting three-dimensional intestinal ‘organoids’ consisted of a polarized, columnar epithelium that was patterned into villus-like structures and crypt-like proliferative zones that expressed intestinal stem cell markers. The epithelium contained functional enterocytes, as well as goblet, Paneth and enteroendocrine cells. Using this culture system as a model to study human intestinal development, we identified that the combined activity of WNT3A and FGF4 is required for hindgut specification whereas FGF4 alone is sufficient to promote hindgut morphogenesis. Our data indicate that human intestinal stem cells form de novo during development. We also determined that NEUROG3, a pro-endocrine transcription factor that is mutated in enteric anendocrinosis, is both necessary and sufficient for human enteroendocrine cell development in vitro. PSC-derived human intestinal tissue should allow for unprecedented studies of human intestinal development and disease.

1782 sitasi en Biology, Medicine
S2 Open Access 2010
Cell culture processes for monoclonal antibody production

Feng Li, N. Vijayasankaran, Amy Shen et al.

Animal cell culture technology has advanced significantly over the last few decades and is now generally considered a reliable, robust and relatively mature technology. A range of biotherapeutics are currently synthesized using cell culture methods in large scale manufacturing facilities that produce products for both commercial use and clinical studies. The robust implementation of this technology requires optimization of a number of variables, including 1) cell lines capable of synthesizing the required molecules at high productivities that ensure low operating cost; 2) culture media and bioreactor culture conditions that achieve both the requisite productivity and meet product quality specifications; 3) appropriate on-line and off-line sensors capable of providing information that enhances process knowledge; and 4) good understanding of culture performance at different scales to ensure smooth scale-up. Successful implementation also requires appropriate strategies for process development, scale-up and process characterization and validation that enable robust operation that is compliant with current regulations. This review provides an overview of the state-of-the art technology in key aspects of cell culture, e.g., engineering of highly productive cell lines and optimization of cell culture process conditions. We also summarize the current thinking on appropriate process development strategies and process advances that might affect process development.

711 sitasi en Engineering, Medicine
DOAJ Open Access 2025
Natural Savannah Systems Within the “One Welfare” Approach: Part 1—Good Farmers’ Perspectives, Environmental Challenges and Opportunities

Marlyn H. Romero, Sergio A. Gallego-Polania, Jorge A. Sanchez

The Colombian Orinoquia is considered one of the eight most important ecosystems in the world. Savannah ecosystems play an essential role in providing ecosystem services. The objectives were (a) to explore and identify the perceptions of traditional farmers and institutional representatives regarding human well-being, animal welfare and the environment, and (b) to identify environmental challenges and opportunities for improvement based on the “One Welfare” concept. Three focal groups were developed: male and female farmers and institutional representatives <i>(n =</i> 24) from Vichada. A thematic analysis, coding with an inductive approach and the definition of themes and sub-themes were carried out. The concept of being “a good farmer” explains the behavior of the producers, where the perception of human well-being is associated with the value of the family and the sense of pride in their tradition as “llanero”. Animal welfare was considered a symbol of profitability and prestige for cattle farmers, a concept that, for them, mixed traditional management, water supply, shade and feed, good health and the natural behavior of cattle. Regarding the environment, this concept is based on their awareness of the importance of conserving the natural savannah. Among the environmental challenges described are climate change, solid waste management and the use of controlled burns. Regarding opportunities for improvement, they proposed strengthening institutional dynamics, partnerships, environmental governance and education. Our results can provide information on the “One Welfare” approach and the motivation of farmers to care for animals and the environment, a fundamental aspect for developing effective intervention strategies.

Veterinary medicine, Zoology
DOAJ Open Access 2025
Effects of the physical form of starter feed on the intake, performance, and health of female Holstein calves

Í.R.R. Castro, G.B.C. Leite, I.F. Carrari et al.

Available literature on the effect of various physical forms of starter feed (PFSF) on calf performance is conflicting. Thus, this study aimed to investigate the effect of the PFSF on feed intake, growth performance, blood metabolites, and the health of dairy calves. Twenty-four female Holstein calves (5-d-old; 40.4 ± 3.86 kg BW; mean ± SD) were used in a completely randomized block design. Calves were individually housed and randomly assigned to the treatments (n = 12 calves/treatment): (1) textured starter feed (TSF, a mix of pelleted ingredients and whole-kernel corn) and (2) pelleted starter feed (PSF). Both starter feeds had the same ingredients, nutrient compositions and pellet die size. Calves were fed the same milk replacer and weaned in a step-down scheme at 67 d. Health was evaluated daily until weaning. Treatments did not affect starter feed intake, water intake, BW, ADG, withers height, or clinical signs of disease (loss of appetite, ear position, and cough incidence). Nonetheless, scores for abnormal attitude (P = 0.01), ocular discharge (P < 0.01), total respiratory disease (P = 0.02), and fecal consistency (P = 0.04) of PSF-fed calves were higher than those TSF-fed. Based on that, TSF-fed calves exhibited a higher non-disease probability compared to PSF over time. Calves TSF-fed sorted against small particles (0.425-mm sieve; P = 0.01). Coincidently, PSF-fed animals sorted for small particles in the same sieve sizes. No major changes in blood profile were found (P > 0.05). In conclusion, starter feeds containing whole-kernel corn as a texturizer did not improve the intake and performance of dairy calves compared with pelleted starter feed; however, improvements were observed in health scores and non-disease probability of calves fed textured starter feed.

arXiv Open Access 2025
Web-Scale Collection of Video Data for 4D Animal Reconstruction

Brian Nlong Zhao, Jiajun Wu, Shangzhe Wu

Computer vision for animals holds great promise for wildlife research but often depends on large-scale data, while existing collection methods rely on controlled capture setups. Recent data-driven approaches show the potential of single-view, non-invasive analysis, yet current animal video datasets are limited--offering as few as 2.4K 15-frame clips and lacking key processing for animal-centric 3D/4D tasks. We introduce an automated pipeline that mines YouTube videos and processes them into object-centric clips, along with auxiliary annotations valuable for downstream tasks like pose estimation, tracking, and 3D/4D reconstruction. Using this pipeline, we amass 30K videos (2M frames)--an order of magnitude more than prior works. To demonstrate its utility, we focus on the 4D quadruped animal reconstruction task. To support this task, we present Animal-in-Motion (AiM), a benchmark of 230 manually filtered sequences with 11K frames showcasing clean, diverse animal motions. We evaluate state-of-the-art model-based and model-free methods on Animal-in-Motion, finding that 2D metrics favor the former despite unrealistic 3D shapes, while the latter yields more natural reconstructions but scores lower--revealing a gap in current evaluation. To address this, we enhance a recent model-free approach with sequence-level optimization, establishing the first 4D animal reconstruction baseline. Together, our pipeline, benchmark, and baseline aim to advance large-scale, markerless 4D animal reconstruction and related tasks from in-the-wild videos. Code and datasets are available at https://github.com/briannlongzhao/Animal-in-Motion.

en cs.CV
arXiv Open Access 2025
CURE: Cultural Understanding and Reasoning Evaluation - A Framework for "Thick" Culture Alignment Evaluation in LLMs

Truong Vo, Sanmi Koyejo

Large language models (LLMs) are increasingly deployed in culturally diverse environments, yet existing evaluations of cultural competence remain limited. Existing methods focus on de-contextualized correctness or forced-choice judgments, overlooking the need for cultural understanding and reasoning required for appropriate responses. To address this gap, we introduce a set of benchmarks that, instead of directly probing abstract norms or isolated statements, present models with realistic situational contexts that require culturally grounded reasoning. In addition to the standard Exact Match metric, we introduce four complementary metrics (Coverage, Specificity, Connotation, and Coherence) to capture different dimensions of model's response quality. Empirical analysis across frontier models reveals that thin evaluation systematically overestimates cultural competence and produces unstable assessments with high variance. In contrast, thick evaluation exposes differences in reasoning depth, reduces variance, and provides more stable, interpretable signals of cultural understanding.

en cs.CL, cs.HC
arXiv Open Access 2025
World in a Frame: Understanding Culture Mixing as a New Challenge for Vision-Language Models

Eunsu Kim, Junyeong Park, Na Min An et al.

In a globalized world, cultural elements from diverse origins frequently appear together within a single visual scene. We refer to these as culture mixing scenarios, yet how Large Vision-Language Models (LVLMs) perceive them remains underexplored. We investigate culture mixing as a critical challenge for LVLMs and examine how current models behave when cultural items from multiple regions appear together. To systematically analyze these behaviors, we construct CultureMix, a food Visual Question Answering (VQA) benchmark with 23k diffusion-generated, human-verified culture mixing images across four subtasks: (1) food-only, (2) food+food, (3) food+background, and (4) food+food+background. Evaluating 10 LVLMs, we find consistent failures to preserve individual cultural identities in mixed settings. Models show strong background reliance, with accuracy dropping 14% when cultural backgrounds are added to food-only baselines, and they produce inconsistent predictions for identical foods across different contexts. To address these limitations, we explore three robustness strategies. We find supervised fine-tuning using a diverse culture mixing dataset substantially improve model consistency and reduce background sensitivity. We call for increased attention to culture mixing scenarios as a critical step toward developing LVLMs capable of operating reliably in culturally diverse real-world environments.

en cs.CV
arXiv Open Access 2025
4D-Animal: Freely Reconstructing Animatable 3D Animals from Videos

Shanshan Zhong, Jiawei Peng, Zehan Zheng et al.

Existing methods for reconstructing animatable 3D animals from videos typically rely on sparse semantic keypoints to fit parametric models. However, obtaining such keypoints is labor-intensive, and keypoint detectors trained on limited animal data are often unreliable. To address this, we propose 4D-Animal, a novel framework that reconstructs animatable 3D animals from videos without requiring sparse keypoint annotations. Our approach introduces a dense feature network that maps 2D representations to SMAL parameters, enhancing both the efficiency and stability of the fitting process. Furthermore, we develop a hierarchical alignment strategy that integrates silhouette, part-level, pixel-level, and temporal cues from pre-trained 2D visual models to produce accurate and temporally coherent reconstructions across frames. Extensive experiments demonstrate that 4D-Animal outperforms both model-based and model-free baselines. Moreover, the high-quality 3D assets generated by our method can benefit other 3D tasks, underscoring its potential for large-scale applications. The code is released at https://github.com/zhongshsh/4D-Animal.

en cs.CV
DOAJ Open Access 2024
Dietary nutrition, intestinal microbiota dysbiosis and post-weaning diarrhea in piglets

Xuebing Han, Xiangdong Hu, Wei Jin et al.

Weaning is a critical transitional point in the life cycle of piglets. Early weaning can lead to post-weaning syndrome, destroy the intestinal barrier function and microbiota homeostasis, cause diarrhea and threaten the health of piglets. The nutritional components of milk and solid foods consumed by newborn animals can affect the diversity and structure of their intestinal microbiota, and regulate post-weaning diarrhea in piglets. Therefore, this paper reviews the effects and mechanisms of different nutrients, including protein, dietary fiber, dietary fatty acids and dietary electrolyte balance, on diarrhea and health of piglets by regulating intestinal function. Protein is an essential nutrient for the growth of piglets; however, excessive intake will cause many harmful effects, such as allergic reactions, intestinal barrier dysfunction and pathogenic growth, eventually aggravating piglet diarrhea. Dietary fiber is a nutrient that alleviates post-weaning diarrhea in piglets, which is related to its promotion of intestinal epithelial integrity, microbial homeostasis and the production of short-chain fatty acids. In addition, dietary fatty acids and dietary electrolyte balance can also facilitate the growth, function and health of piglets by regulating intestinal epithelial function, immune system and microbiota. Thus, a targeted control of dietary components to promote the establishment of a healthy bacterial community is a significant method for preventing nutritional diarrhea in weaned piglets.

DOAJ Open Access 2024
Identifying Dietary Timing of Organic Trace Minerals to Reduce the Incidence of Osteomyelitis Lameness in Broiler Chickens Using the Aerosol Transmission Model

Khawla Alharbi, Andi Asnayanti, Anh Dang Trieu Do et al.

Our prior research demonstrated a 20% to 25% reduction in bacterial chondronecrosis with osteomyelitis (BCO) lameness in broilers with organic Zn, Mn, and Cu (Availa<sup>®</sup> ZMC) supplementation. Expanding on this, we investigated the optimal timing for Availa<sup>®</sup> ZMC feeding to mitigate BCO lameness and reduce feed additive costs in the poultry industry. In this study, we compared the application of 0.15% Availa<sup>®</sup> ZMC for 56 days, the first 28 days, and the last 28 days. The experimental design was a randomized block design involving 1560 one-day-old chicks distributed across two wire-floor pens as BCO source infection and four treatment groups with six replicates. The source of BCO infection exhibited a cumulative lameness incidence of 83%, whereas the negative control group showed a 77% cumulative incidence of lameness (<i>p</i> = 0.125). Administering 0.15% of Availa<sup>®</sup> ZMC during the initial 28 d resulted in a 41.3% reduction in BCO incidence, significantly different from the supplementation during the last 28 d (<i>p</i> < 0.05). However, this reduction did not differ substantially (<i>p</i> > 0.05) from the 56d application period. Hence, administering 0.15% Availa<sup>®</sup> ZMC during the first four weeks emerges as the optimal timing protocol, providing a defense against lameness comparable to the continuous supplementation throughout the complete production duration. Implementing this feeding approach reduces the cost of feed additive, promotes the health of skeletal bones, and effectively protects against BCO lameness in broilers, offering a valuable consideration for producers seeking optimal outcomes in the poultry industry.

Veterinary medicine, Zoology
arXiv Open Access 2024
Models of Animal Behavior as Active Particle Systems with Nonreciprocal Interactions

Amir Haluts, Dan Gorbonos, Nir S. Gov

Active particle systems of interacting self-propelled particles offer a versatile framework for modeling complex systems. When employed to describe aspects of animal behavior, the complexity of animal movement and decision-making often requires the use of unique types of effective interactions between the particles -- notably nonreciprocal effective forces that do not obey the usual conservation laws of Newtonian mechanics. Here we review two recent empirically-motivated models, of two very different types of animal behavior, where the behavior is described in terms of active particles which interact through nonreciprocal effective forces. The first model describes the dynamics of animal contests, wherein typically two rivals fight over a localized resource. The uniquely shaped effective potentials between the model's 'contestant particles' manifest the adversarial nature of contest interactions and capture the dynamical essence of contest behavior in space and time. The second model describes the stabilization of cohesive swarms through long-range and adaptive gravity-like attraction. This 'adaptive gravity' model explains the observed mass and velocity profiles of laboratory midge swarms. These examples demonstrate that theoretical models that use the framework of active particles to describe animal behavior can expand the scope of active-particle research, as well as explain complex phenomena in animal behavior.

en physics.bio-ph, cond-mat.stat-mech

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