# Animal Research Report: [Short title of the study]

> Report template for in vivo research using animals. The sections cover
> the topics of the ARRIVE 2.0 guidelines, both the Essential 10 and the
> Recommended Set, arranged in manuscript order and written in original
> words for this collection. Use it with the official ARRIVE checklist and
> explanation document from arriveguidelines.org and with your
> institution's animal welfare requirements. This is a reporting format,
> not veterinary, ethical or statistical advice. Replace every
> `[bracketed]` value and every row marked *Example*.

<!--
Guidance: How to use this template
- The Essential 10 are the minimum a reviewer needs to judge reliability.
  Fill every one of them before anything else; headings carry the ARRIVE
  item number in brackets so you can map them to the checklist.
- Report each experiment separately when a study contains several. Copy
  the methods tables per experiment and label them EXP-01, EXP-02.
- Give exact numbers of animals at every stage and say what the
  experimental unit was (animal, litter, cage, tissue sample).
- Report negative and inconclusive results with the same detail as
  positive ones.
- Never paste raw welfare incident data that could identify staff or
  facilities against local policy.
-->

## Document control

<!-- Guidance: Treat the study report as a controlled document linked to the approved project licence or protocol. -->

| Field | Value |
|---|---|
| Document ID | [ANI-STUDY-001] |
| Project licence / protocol | [Licence or IACUC protocol number] |
| Ethics committee | [Animal welfare body / IACUC name and approval number] |
| Preregistration | [Registry and identifier or "not registered"] |
| Version | [0.1] |
| Status | [Draft / In review / Approved] |
| Owner | [@principal-investigator] |
| Approvers | [@named-veterinary-surgeon], [@statistician] |
| Last updated | YYYY-MM-DD |
| Classification | [Confidential until publication] |

### Approvals

| Role | Name | Decision | Date |
|---|---|---|---|
| Principal investigator | [@name] | [Approved] | YYYY-MM-DD |
| Named veterinary surgeon / attending veterinarian | [@name] | [Reviewed welfare sections] | YYYY-MM-DD |
| Statistician | [@name] | [Approved] | YYYY-MM-DD |

## Revision history

<!-- Guidance: Record each draft and any reanalysis. -->

| Version | Date | Author | Change summary |
|---|---|---|---|
| 0.1 | YYYY-MM-DD | [@name] | First draft after unblinding |
| 0.2 | YYYY-MM-DD | [@name] | *Example:* Added litter as random effect after statistical review |
| 1.0 | YYYY-MM-DD | [@name] | Approved for submission |

## Contents

<!-- Guidance: Keep in sync with the headings below. -->

1. [Title and abstract](#1-title-and-abstract)
2. [Introduction](#2-introduction)
3. [Methods](#3-methods)
4. [Results](#4-results)
5. [Discussion](#5-discussion)
6. [Other information](#6-other-information)
7. [Appendices](#7-appendices)

## 1. Title and abstract

<!-- Guidance: (ARRIVE 11) The abstract should let a reader judge the species, design, key methods, results and conclusion without opening the paper. -->

The title names the species and the main intervention; the abstract
summarises objectives, species, methods, results and conclusions.

**Title:** [Effect of [intervention] on [outcome] in [species and strain,
sex] model of [condition]]

| Heading | Content |
|---|---|
| Objective | [Research question] |
| Animals | *Example:* 48 male and female C57BL/6J mice, 10-12 weeks old |
| Design | [Randomised, blinded, number of groups, experimental unit] |
| Main outcome | [Primary outcome and time point] |
| Results | [Effect size with 95% CI for the primary outcome] |
| Conclusions | [Proportionate to the evidence] |

## 2. Introduction

<!-- Guidance: Explain why the study was done and why the chosen species and model are relevant to the question. -->

The introduction justifies the research and the use of animals.

### 2.1 Background (ARRIVE 12)

[Summarise the scientific background and the gap. Explain why animals
were needed, why this species and model were chosen and how the model
relates to the human or animal condition of interest.]

### 2.2 Objectives (ARRIVE 13)

| ID | Objective or hypothesis | Type |
|---|---|---|
| OBJ-01 | *Example:* Treatment with [compound] at 10 mg/kg reduces infarct volume at 24 hours compared with vehicle | Primary, confirmatory |
| OBJ-02 | [Secondary objective] | Secondary |
| OBJ-03 | [Exploratory question] | Exploratory |

## 3. Methods

<!-- Guidance: Report the Essential 10 methods items fully. If a study has several experiments, give each its own design table. -->

This section describes the ethical framework, design and procedures.

### 3.1 Ethical statement (ARRIVE 14)

[Name the ethical review body, the approval or licence number and the
legislation or guidelines followed. If no approval was required, explain
why.]

### 3.2 Study design (ARRIVE 1)

<!-- Guidance: State the groups compared, including controls, and the experimental unit. A diagram helps readers follow complex designs. -->

| Item | Detail |
|---|---|
| Experiment ID | [EXP-01] |
| Groups | *Example:* Vehicle; compound 3 mg/kg; compound 10 mg/kg; sham surgery |
| Control groups | [Vehicle, sham, positive control] |
| Experimental unit | [Single animal / cage / litter] and rationale |
| Design type | [Completely randomised / randomised block / crossover] |

The design is summarised below.

```mermaid
flowchart LR
    A["Animals received (n = [52])"] --> B["Acclimatised 7 days"]
    B --> C["Randomised (n = [48])"]
    C --> D["Vehicle (n = [12])"]
    C --> E["Low dose (n = [12])"]
    C --> F["High dose (n = [12])"]
    C --> G["Sham (n = [12])"]
```

### 3.3 Sample size (ARRIVE 2)

<!-- Guidance: Give the exact number per group and in total, and explain how it was decided. A power calculation needs the effect size, variability, alpha and power and their sources. -->

For a two-group comparison of means, the number per group is:

$$
n = \frac{2\,\sigma^{2}\,\left(z_{1-\alpha/2} + z_{1-\beta}\right)^{2}}{\Delta^{2}}
$$

*Example:* Expected difference $\Delta = 20\ \text{mm}^3$, standard
deviation $\sigma = 15\ \text{mm}^3$ from pilot data, two-sided
$\alpha = 0.05$ and 80% power give
$n = 2 \times 225 \times (1.96 + 0.84)^{2} / 400 \approx 8.8$, rounded up
to 9; 12 per group were used to allow for an expected 20% surgical
mortality.

When a power calculation is not possible, for example in exploratory
work, the resource equation gives an upper bound:

$$
E = N - T, \qquad 10 \le E \le 20
$$

where $N$ is the total number of experimental units and $T$ the number
of treatment groups.

| Group | Animals allocated | Animals analysed |
|---|---|---|
| [Vehicle] | [12] | [10] |
| [Low dose] | [12] | [11] |
| [Total] | [48] | [42] |

### 3.4 Inclusion and exclusion criteria (ARRIVE 3)

<!-- Guidance: Set criteria before the experiment. Report every animal or data point excluded, with the reason, and the numbers in each group. -->

| Criterion | Type | Set a priori? |
|---|---|---|
| *Example:* Cerebral blood flow drop below 70% of baseline during occlusion | Inclusion | Yes |
| Death before outcome assessment | Exclusion | Yes |
| [Criterion] | [Inclusion / Exclusion] | [Yes / No] |

| Animal ID | Group | Excluded at stage | Reason |
|---|---|---|---|
| [M-017] | [Vehicle] | [Surgery] | [Haemorrhage] |

### 3.5 Randomisation (ARRIVE 4)

[Say whether randomisation was used to allocate units to groups, the
method used to generate the sequence (for example a computer random
number generator, blocked by cage or batch), and how confounders such as
order of treatment and measurement or cage location were controlled.]

*Example:* Animals were allocated to the four groups in blocks of four
using a sequence generated in R (`set.seed(20250314)`, `sample()`) by a
colleague not involved in surgery. Each block was one surgery day, so
every group was represented on every day. Cage positions on the rack and
the order of outcome assessment followed the same random sequence.

| Potential confounder | Control method |
|---|---|
| Order of surgery | [Randomised within day] |
| Cage position | [Randomised rack location] |
| Operator | [Single surgeon for all animals / balanced across groups] |
| Batch of compound | [Single batch, lot number] |

### 3.6 Blinding (ARRIVE 5)

<!-- Guidance: Report who knew the allocation at each stage: allocation, conduct of the experiment, outcome assessment and data analysis. -->

| Stage | Was the person aware of group? | How blinding was achieved |
|---|---|---|
| Allocation | [Yes / No] | [Method] |
| Conduct of experiment | [Yes / No] | *Example:* Solutions coded A to D by a colleague not involved in surgery |
| Outcome assessment | [Yes / No] | [Coded image files] |
| Data analysis | [Yes / No] | [Code broken after analysis was locked] |

### 3.7 Outcome measures (ARRIVE 6)

| ID | Outcome | Definition and method | Time point | Primary? |
|---|---|---|---|---|
| OUT-01 | *Example:* Infarct volume | TTC staining, volumetric analysis corrected for oedema | 24 h | Yes |
| OUT-02 | [Neurological score] | [Scale and reference] | [24 h, 72 h] | No |
| OUT-03 | [Body weight] | [Daily weighing] | [Daily] | No |

### 3.8 Statistical methods (ARRIVE 7)

<!-- Guidance: Name the method for each analysis, the software, and how assumptions were checked. Account for the experimental unit (for example litter or cage as a random effect). -->

| Item | Method |
|---|---|
| Primary analysis | *Example:* One-way ANOVA with Dunnett's comparison against vehicle |
| Assumption checks | [Residual plots; Shapiro-Wilk; transformations used] |
| Clustering | [Litter or cage as random effect] |
| Effect measure | [Mean difference with 95% CI] |
| Software | [Name and version] |

### 3.9 Experimental animals (ARRIVE 8)

| Item | Detail |
|---|---|
| Species and strain | *Example:* Mus musculus, C57BL/6J |
| Sex | [Male and female; rationale if single sex] |
| Age and weight | [10-12 weeks; 22-28 g at start] |
| Source | [Supplier or in-house colony] |
| Genetic modification | [Allele nomenclature, background, generation] |
| Health status | [Specific pathogen free; health monitoring report] |
| Previous procedures | [None / describe] |

### 3.10 Experimental procedures (ARRIVE 9)

<!-- Guidance: Describe each procedure so it can be replicated: what, how, when, where and why, including anaesthesia, analgesia and euthanasia. -->

| Procedure | What and how | When | Where | Why |
|---|---|---|---|---|
| Anaesthesia | [Agent, dose, route, monitoring] | [Day 0] | [Surgery room] | [Surgery] |
| Intervention | *Example:* [Compound] 10 mg/kg intraperitoneally in 5 ml/kg saline | 30 min after occlusion | Home cage | Test hypothesis |
| Analgesia | [Agent, dose, frequency] | [Peri-operative] | [Location] | [Welfare] |
| Euthanasia | [Method] | [24 h] | [Location] | [End point] |

### 3.11 Housing and husbandry (ARRIVE 15)

| Condition | Detail |
|---|---|
| Housing | [Individually ventilated cages, animals per cage] |
| Bedding and enrichment | [Type] |
| Light cycle | *Example:* 12:12 h light-dark, lights on 07:00 |
| Temperature and humidity | [Range] |
| Diet and water | [Diet name, ad libitum] |

### 3.12 Animal care and monitoring (ARRIVE 16)

[Describe steps to reduce pain, suffering and distress; the expected
and unexpected adverse events and how they were managed; and the humane
end points with their criteria and the frequency of monitoring.]

| Humane end point | Criterion | Monitoring frequency | Action |
|---|---|---|---|
| Weight loss | *Example:* More than 20% of baseline | Daily | Euthanasia |
| [Clinical score] | [Threshold] | [Frequency] | [Action] |

## 4. Results (ARRIVE 10)

<!-- Guidance: For each experiment and each outcome, give summary statistics per group with a measure of variability and, where applicable, the effect size with a confidence interval. Prefer showing individual data points in figures. -->

This section reports the numbers analysed and the outcomes.

### 4.1 Animals analysed

| Group | Allocated | Excluded | Analysed |
|---|---|---|---|
| [Vehicle] | [12] | [2] | [10] |
| [Low dose] | [12] | [1] | [11] |
| [High dose] | [12] | [2] | [10] |
| [Sham] | [12] | [1] | [11] |

### 4.2 Outcomes

| Outcome | Group | n | Mean (SD) | Difference vs control (95% CI) |
|---|---|---|---|---|
| OUT-01 | Vehicle | [10] | *Example:* 62.4 (14.8) | Reference |
| OUT-01 | High dose | [10] | 41.9 (13.2) | -20.5 (-33.7 to -7.3) |
| [Outcome] | [Group] | [n] | [Value] | [Value] |

### 4.3 Adverse events

[Report all adverse events in each group, any modifications to
procedures to reduce them, and animals reaching humane end points.]

| Event | Vehicle | Low dose | High dose | Sham | Action taken |
|---|---|---|---|---|---|
| Death during surgery | [1] | [0] | [1] | [0] | *Example:* Anaesthetic depth monitoring tightened from day 3 |
| Humane end point reached | [1] | [1] | [1] | [0] | Euthanised per protocol |
| [Other event] | [n] | [n] | [n] | [n] | [Action] |

## 5. Discussion

<!-- Guidance: Interpret results against the objectives, address limitations and bias, and be careful about translation to humans. -->

The discussion interprets the findings and their relevance.

### 5.1 Interpretation and scientific implications (ARRIVE 17)

[Interpret the results in light of the objectives and the literature.
Discuss limitations, including sources of bias, limits of the model and
imprecision. Describe any implications for replacement, refinement or
reduction (the 3Rs).]

*Example:* A single dose of [compound] given 30 minutes after occlusion
reduced infarct volume by about a third compared with vehicle. The
estimate is imprecise, and the study was powered for one dose and one
time point only. Efficacy in aged animals or animals with comorbidities,
which better reflect the clinical population, was not tested.

### 5.2 Generalisability and translation (ARRIVE 18)

[Comment on whether, and how, the findings are likely to apply to other
species, strains, sexes or experimental conditions, and their relevance
to human biology.]

## 6. Other information

<!-- Guidance: Transparency items that let others check, reuse and trust the work. -->

These items support transparency and reuse.

### 6.1 Protocol registration (ARRIVE 19)

[State whether a protocol, including the research question, key design
features and analysis plan, was prepared before the study and whether
and where it was registered, for example preclinicaltrials.eu or OSF.]

### 6.2 Data access (ARRIVE 20)

[Statement describing whether and where the study data are available,
for example a public repository with a persistent identifier.]

### 6.3 Declaration of interests (ARRIVE 21)

| Item | Detail |
|---|---|
| Competing interests | [Statement for each author, or "none"] |
| Funding | [Funder, grant number] |
| Role of funder | [Role in design, analysis, publication, or none] |

## 7. Appendices

<!-- Guidance: Supplementary material reviewers need. -->

Supporting material for reviewers:

| Appendix | Content |
|---|---|
| A | Completed ARRIVE 2.0 checklist with page numbers |
| B | Individual animal data and exclusion log |
| C | Welfare scoring sheet and humane end-point criteria |
| D | Glossary: [3Rs replacement, reduction, refinement; IACUC institutional animal care and use committee; SPF specific pathogen free] |

## Standard and licence note

Based on the ARRIVE guidelines 2.0: Percie du Sert N, Hurst V, Ahluwalia
A, et al., *The ARRIVE guidelines 2.0: updated guidelines for reporting
animal research* (PLoS Biol 2020;18(7):e3000410),
https://arriveguidelines.org. The guidelines are published open access
under a Creative Commons Attribution licence; this template uses their
item topics and numbering only, paraphrased in original text, and
reproduces no checklist wording. Use the official checklist and the
explanation and elaboration document when submitting. This is a
reporting format, not veterinary, ethical or statistical advice; follow
your national legislation and institutional animal welfare policy.
Template licence: MIT.