The 3-3-3 Rule of Adopting a Rescue Dog

A Veterinarian’s Guide to Creating Calm, Connection, and Confidence

Bringing a rescue dog into your home is an incredibly rewarding experience, but it’s also a big adjustment for both of you. Whether your new best friend has come from a shelter, foster care, or a difficult past, it’s essential to understand that healing takes time. That’s where the 3-3-3 Rule comes in.

This rule is a helpful framework to guide expectations during the first 3 days, 3 weeks, and 3 months of your dog’s transition into their new life. As an integrative veterinarian, I’ve seen firsthand how crucial it is to support not just the physical but also the emotional and gut-brain health of our pets during this time. After all, a calm gut is often the foundation of a calm mind.

Let’s explore what the 3-3-3 Rule really means and how you can support your new dog’s emotional and physiological wellbeing right from day one.

The First 3 Days: Decompression

The first few days in a new home can be overwhelming for any dog, especially one who has experienced stress, change, or trauma. Don’t be surprised if your dog seems nervous, withdrawn, or even disinterested in food or affection. This is completely normal.

During these early days, your job is to provide structure, safety, and softness.

• Keep things calm. Avoid overstimulation. No big welcomes, dog parks, or overwhelming introductions. Instead, offer a quiet space where your dog can decompress.
• Observe, don’t expect. Your dog may not reveal their true personality just yet. Let them come to you in their own time.
• Stick to a routine. Consistent feeding, gentle walks, and restful downtime provide a sense of security.

From an integrative veterinary perspective, this is not the time to make dramatic dietary changes. Even if your long-term goal is a fresh, wholefood diet like Big Dog’s, it’s best to wait until your dog is more emotionally and physiologically settled (usually after the first couple of weeks).

However, that doesn’t mean you can’t start supporting their internal health. A gentle, high-quality pre and probiotic can be introduced during this early phase to:

• Help rebalance the gut microbiome after stress
• Improve digestion and nutrient absorption
• Support immune function
• Prepare the gut for a smoother transition to a more nourishing diet later on

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You can do this with Big Dog Pet Food’s species specific probiotic range.

These foundational steps help reduce the risk of gut upsets like diarrhoea or bloating, common issues in stressed dogs, while laying the groundwork for long-term gut-brain harmony.

It’s also worth considering introducing a targeted stress support supplement to help gently wind down your dog’s stress pathways. Formulas that support the gut-brain axis, particularly those containing adaptogens, calming herbs like chamomile or valerian, and medicinal mushroom extracts, can help regulate the nervous system and promote emotional stability.

Additionally, diffusing calming essential oils (like lavender or frankincense but ensuring they’re safe) or using dog-specific pheromone sprays and plug-ins can create a more soothing environment. Preliminary research has shown that lavender essential oil may help reduce stress-related behaviours in shelter dogs, making it a potentially beneficial support during the early days of adjustment (Stanghellini and Lupo, 2019). These tools can be especially helpful for rescue dogs who may be hypersensitive to unfamiliar smells and sounds.

These subtle, supportive steps send a powerful signal: you’re safe now. You’re home.

The First 3 Weeks:
Settling In

At this point, your dog may begin to feel more comfortable. Their personality will start to emerge, and they might begin testing boundaries. This is often when new behaviours pop up, chewing, barking, or signs of separation anxiety. Research shows that owner satisfaction in dog adoptions is closely linked to understanding and managing expectations during this transitional period (Dinwoodie et al., 2022).

This is the phase of relationship building.

• Gently introduce training. Keep sessions short, positive, and consistent.
• Continue to support their nervous system. Use enrichment, calming routines, and time outdoors to help regulate their emotional state.
• Be patient. Behaviour isn’t always linear. Some days will be better than others.

During this stage, your dog is learning your routine and beginning to predict your patterns. Consistency is key, it builds confidence and helps your dog feel secure in their new environment. Predictability reduces anxiety and allows them to begin relaxing into their new life.

From a veterinary perspective, this is where I often see the impact of emotional contagion between humans and pets. Your dog is watching you constantly, your tone of voice, body language, and emotional state all feed into their perception of safety.

If you’re stressed, your dog absorbs that energy. This mirroring phenomenon is well-documented in both veterinary behaviour studies and human-animal bonding research.

Supporting yourself during this time is just as important as supporting your dog. Your calmness becomes their calmness.

And of course, diet continues to play a key role. A fresh food diet that includes probiotics, prebiotics, and bioavailable nutrients can help to stabilise digestion, which has a direct calming effect via the vagus nerve (Sacoor et al., 2024). Balanced fresh food diets like Big Dog’s are rich in enzymes and naturally occurring gut-supportive ingredients, making it easier for a stressed gut to digest, absorb, and heal. It’s important to ensure a slow and smooth transition of a fresh food diet over a couple of weeks.

The First 3 Months: Building Trust and Confidence

By now, your dog likely knows the household routine and may be bonded to their new family. But this doesn’t mean the journey is over. This is a pivotal phase in laying down long-term trust, behavioural stability, and emotional resilience.

• Consistency remains key. Dogs thrive on routine and predictability.
• Support socialisation. Slowly introduce new people, dogs, and environments, always watching for signs of overwhelm.
• Advance your enrichment. Puzzle toys, scent work, and “calm energy” playtime can deepen your bond and stimulate healthy brain development.

From an integrative health standpoint, this is when I often recommend fine-tuning diet and supplements to continue nourishing the gut-brain connection. This axis is the superhighway between your dog’s gastrointestinal system and their emotional regulation centre, and it remains active long after initial stress has passed.

A well-functioning gut helps produce key neurotransmitters like serotonin and GABA, both of which are critical for reducing anxiety and promoting a sense of safety. That’s why I always recommend a minimally processed, wholefood-based diet like Big Dog Pet Food’s for dogs who are rebuilding from the inside out.

Final Thoughts: Trust the Timeline, Trust Your Dog

Rescuing a dog isn’t just about providing a home, it’s about offering a second chance at life, safety, and connection. The 3-3-3 Rule is a powerful reminder to slow down, honour your dog’s process, and support them holistically, mind, body, and gut.

Whether it's day 3 or day 300, the foundations you lay early on, emotional regulation, healthy nutrition, and calm connection, will ripple through your dog’s entire life.

And if you’re wondering where to start? Begin in the gut. A fresh, recognisable, and biologically appropriate diet like Big Dog Pet Foods is one of the most powerful tools we have to help dogs settle not just into our homes, but into their own bodies and hearts.

Need More Support?

If you feel like you or your new dog need extra help during the transition, here are some trusted resources and services in Australia:

• Fear Free Certified Trainers – Look for trainers who are certified in Fear Free methods to ensure your dog’s emotional safety. You can search by location at www.fearfreepets.com.
• Veterinary Behaviourists – Each state in Australia has qualified veterinary behaviourists who can support more complex behavioural and emotional issues. Two excellent directories to explore include:
  • petbehaviourvet.com.au
  • wildthingvet.com
  • RSPCA Knowledgebase – Offers practical tips on settling in, behaviour, and responsible pet care. kb.rspca.org.au
  • Find an Integrative Vet – Use the CIVT Directory to locate a local integrative veterinarian who can support your dog’s emotional and physiological wellbeing.

References

Dinwoodie, Ian R., Vivian Zottola, Karla Kubitz, and Nicholas H. Dodman. "Selection Factors Influencing Eventual Owner Satisfaction about Pet Dog Adoption." Animals 12, no. 17 (2022): 2264. https://doi.org/10.3390/ani12172264.

Sacoor, Carina, John D. Marugg, Nuno R. Lima, Nuno Empadinhas, and Liliana Montezinho. "Gut-Brain Axis Impact on Canine Anxiety Disorders: New Challenges for Behavioral Veterinary Medicine." Veterinary Medicine International, January 23, 2024. https://doi.org/10.1155/2024/2856759.

Stanghellini, Andrea Lupo. "Effect of Lavender (Lavandula angustifolia) Essential Oils on Sheltered Dog Behavior: Preliminary Results." Dog Behavior 5, no. 3 (2019): 19–22. https://doi.org/10.4454/db.v5i3.111.

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