Research articles

This study explores the use of electrical stunning as a viable alternative to anesthetic overdose and rapid cooling for euthanizing zebrafish larvae, potentially improving the welfare of over 5 million zebrafish in biomedical research.

Differences in standard chow diets can influence mouse model phenotypes and impact experimental reproducibility. Here Knuth et al. show that the timing during which mice are exposed to standard chow can also affect phenotypic outcomes.

The marble burying task (MBT) is used to measure anxiety-like behavior, relying on a snapshot of the number of marbles buried at the end of the test. This Brief Communication introduces a more extensive behavioral analysis to improve the translational value of MBT for clinical psychological phenotypes.

This Protocol describes a minimally invasive technique for central nervous system drug delivery in rodents. The procedure allows the use of the transnasal route to deliver blood–brain barrier-impermeant drugs.

This study describes a new pig model of autism induced by embryonic exposure to valproic acid. The pig model displays behavioral alterations, abnormal gait and increased anxiety, which recapitulate key features of autism.

This systematic review identifies substantial heterogeneity in the experimental conditions in zebrafish nutrition studies, highlighting the urgent need for further research and the importance of standardized parameters for future zebrafish studies.

The authors describe a novel mouse model of cardiovascular–kidney–metabolic syndrome induced by unilateral nephrectomy and a Western diet rich in carbohydrates, fat and salt, which could be used to study human condition and identify therapies.

This Protocol describes a novel ischemic heart injury method in neonatal mice via cauterization of the root of the left coronary artery. The procedure is technically straightforward, requiring less than 10 min per mouse for completion.

Meijs et al. perform an electrophysiological investigation of cortical responses in a pig nerve injury model, showing the role of layer III–VI neurons in altered primary somatosensory cortex excitability after nerve injury.

Severe combined immunodeficiency (SCID) pigs do not live long enough to reproduce naturally. Monarch et al. show that reconstituting the immune system of SCID piglets with fetal bone allografts extends their lifespan, allowing them to reach puberty.

This study shows that using gene-editing technology in oocytes using Platinum TALEN is an effective method for producing genetically modified marmosets by exon skipping.

Free flap is widely used in head and neck reconstructive surgery, but fluid management of surgical patients remains controversial. Here, Thiem et al. used a pig model to monitor the effects of volume management on free flap perfusion and metabolism.

Pairing palatable formulations with micropipette dosing for administration of water-insoluble drugs such as tamoxifen in mice promotes voluntary consumption without loss of efficacy compared to more invasive administration methods.

This study reports the use of fluorescently labeled collagen hybridizing peptides to directly image collagen remodeling and monitor fibrosis in two mouse models of ocular neovascularization.

Preece et al. show that B6SPRTF1 hybrid males between C57BL/6J and Mus spretus are suitable for the generation of pseudopregnant female mice for embryo transfer. By providing an alternative to vasectomized males, the method shows clear 3R benefits.

The study reveals that raising mice at 22 °C boosts gut transit speed by two times compared to 30 °C, primarily due to stress signals from the hypothalamic–pituitary–adrenal axis and an increase of corticotropin-releasing hormone.

Researchers have developed a cost-effective, noninvasive method for determining torpor-bout duration in heterothermic mammals. They used the paper towel shredding behavior of ground squirrels to detect 59 arousals with 100% accuracy over 52 days. This method avoids the drawbacks of other cheap monitoring systems such as the sawdust technique.

The authors defined rat microbial biogeography by re-analyzing publicly available RNA sequencing data from 11 organs of juvenile, adolescent, adult and aged Fisher 344 rats.

The study introduces an open-source, customizable 3D printable design for rodent conditioning for magnetic resonance imaging and other imaging modalities. The design is easy to use and can be applied to both anesthetized and awake mice, and anesthetized rats.

Poor replicability in animal research can be a result of low external validity driven by rigorous standardization of study populations. This study investigates how heterogenization of study populations by using mice from different breeding sites might affect the replicability of animal studies conducted in a single facility. The findings suggest that heterogenization by breeding site has limited capacity to improve replicability in animal research.