Fiona Farmer BVSc MRCVS goes behind the scenes of a veterinary diagnostic laboratory to find out more about the people and processes and the tests and technologies – and how to make the most of your lab services to support patient care. Here she explores the Microbiology department at NationWide Laboratories.

As a vet, you know the importance of accurate diagnostics. But how much do you know about the people and processes that underpin those results? In this second instalment of my visit to NationWide Laboratories, I stepped into the microbiology department to learn what really goes into processing the samples we send. From faecal samples to ear swabs and everything in between, come with me to meet the people whose expertise supports our diagnoses every day.

The Journey of a Sample

Samples arrive at the lab through reception, where they are checked, logged and sorted by department. In microbiology, samples include faeces, skin swabs, ear swabs, abscesses, urine and more, with each sample requiring a different approach.

Faecal samples are typically tested for parasites and may also undergo bacteriology, for pathogens such as salmonella. “We are always very busy at the start of the month – we service a lot of zoo clients, so we have to do regular screening for all kinds of animals!” explains Alan.

Swabs arriving for culture also follow a process.

Cultures are set up on agar plates and incubated for 24 to 48 hours, depending on the suspected pathogen. Identification may involve biochemical tests, mass spectrometry, or PCR. Gram stains performed first to identify bacterial types and give an early indication of infection. A Gram stain gives us a sense of what we’re dealing with – cocci or rods, Gram-positive or negative. That informs the next steps.

To support faster and more accurate bacterial identification, the microbiology team now uses a rapid protein-based identification method. “It’s incredibly efficient,” says Michelle. “We can get results quicker, which helps vets make faster, more targeted treatment decisions.” As well as improving turnaround times, this approach supports antimicrobial stewardship by guiding appropriate antibiotic use and helping detect zoonotic threats early.

Sensitivity testing is another key step. Once a pathogen is identified, the team tests its susceptibility to different antibiotics, using documented guidelines to report whether it’s sensitive, intermediate, or resistant.

Once a sample has been processed it must be reported, and the team aims to get results sent back out to referring vets as quickly as possible, although the speed at which results can be sent back very much depends on the testing involved. “We do all of the straightforward reporting between us, but for the more complex cases we refer to our pathologists or internal medic”, shares Hayley.

Urine – what you need to know

Urine always gets examined the same day it arrives – this includes urinalysis and examining the sediment.
If culture is required, the report will wait until culture is complete and everything will be sent together.
Urine should be sent in a boric acid tube and filled to the line. If it is underfilled it can cause toxicity and kill certain pathogens.
Cystocentesis will provide the best results if this method of collection is possible.

Faeces – what you need to know

Send enough poo! “We need at least three grams to perform a worm egg count.” Although some tests, such as Baermann’s, require ten grammes.
Collect faeces over three days. Because worms shed intermittently the best way to be thorough is to collect faecal samples over the course of three days.
History is important – key information such as letting us know the dog is coughing will influence the tests we run.

Top Tips from the Micro Lab

Label everything clearly. Tubes and forms should match. Include the site and type of sample.
History of travel. It’s very important that we are told if an animal has recently travelled (worldwide) or been imported from Europe.
Send cytology to weed out contamination. “We get a lot of samples that are clearly contaminated. If you can run a cytology in-house and send that in with your sample, it helps us to distinguish between contaminants.”
Give us the full story. The more relevant clinical history is provided, the better the lab can interpret the results. “We often just get a blank page when it comes to history. But the more information we get, the more it helps us.”
Store and send samples correctly. Swabs should be sent in transport medium and not sent dry. Faeces should be sent in universal containers, not Tupperware or gloves! And if you are pooling over three days, keep samples refrigerated. Make sure the lids are on tightly. For hair samples make sure there are no blades in the skin scrapes.
Sensitivity panel is not a magic bullet! The results must be evaluated along with the whole clinical situation and patient.

Q&A with the Microbiology Team

Q: What are the most common issues you see with submissions?

A: Mislabelling and contamination are the biggest problems. Also, missing patient history.

Q: What makes a good sample?

A: Clear labelling, proper collection (e.g., cystocentesis for urine), and good clinical notes.

Q: When is a culture not helpful?

A: In cases where the area is already colonised, like surface wounds. You’re more likely to grow commensals than pathogens.

Q: Why do swabs need to be sent in transport medium?

A: Without appropriate transport medium there is the risk of desiccation of bacteria, which means we can’t provide accurate results

Q: Why do you want a cytology along with a swab when sampling ears?

A: It helps us identify the causative pathogens and rule out contaminants which ultimately play a role in antimicrobial stewardship. “It’s common to get a mixed culture from the swab, but if the cytology shows positive cocci, you know what the causative agent is”.

Q: What does a positive result really mean?

A: It depends on context. That’s why history is important. We interpret results differently based on where the sample came from and what signs the patient has.

Q: Do you ever speak to vets directly?

A: Not often directly, but through pathologists. If something’s odd or needs clarification, we feed it back.

Meet the team

The microbiology department at NationWide Laboratories spreads across four areas of expertise: bacteriology, faecal parasitology, urine and hair testing, and water microbiology. I met Michelle Pittilla, head of microbiology, and her team, Alan Garnett and Hayley Mullaney from the fecal parasitology department. Combined, they have spent almost 30 years working at NationWide Laboratories.

Michelle Pittilla – Head of Microbiology

“I first joined NationWide Laboratories back in 2005 as a Laboratory Technician, fresh out of university and eager to put my Biomedical Science degree from the University of Central Lancashire into action. From the start, I was fascinated by the detail and precision of microbiology, and the incredible impact it has on animal and public health. Over the years, I’ve worked my way through a variety of roles, from Senior Laboratory Scientist to Head of Food Microbiology, gaining experience in everything from food safety and environmental testing to clinical diagnostics. In April 2024, I stepped into my current role as Head of Microbiology. I oversee the daily operations of the microbiology department at our Poulton-le-Fylde site, handling patient samples, water testing, and ensuring quality at every step. One of my favourite parts of the job is training new team members. I love helping people not only learn how to do things, but understand why they matter, because every test, every culture, and every result plays a vital role in supporting our clients and the animals they care for.”

Hayley Mullaney – Laboratory Scientist

“After more than 20 years working as a zookeeper, I decided it was time for a big career change! In 2020, I moved back up North from the Cotswolds to be closer to my family, and when a friend told me about an opportunity at NationWide Laboratories, I thought, why not give it a go? That’s how my journey in veterinary diagnostics began. Since joining the Microbiology department, I’ve trained across all areas of the lab’s setup procedures. I’m signed off to read hair samples, parasites, and faecal culture plates, and I’m currently training to read urine sediments. It’s amazing how much detail goes into each sample, every result contributes to helping vets make the right decisions for their patients, which makes the work really rewarding. Lab life brings its share of surprises. I have learned to watch out for fizzy exploding poos in pots sent in. These samples can cause quite a mess in the lab! Outside of work, I love walking, watching TV series, and going to the theatre, especially musicals. I’ve recently got into birdwatching, and I spend a lot of weekends supporting my nephews and niece at horse shows. I used to ride and compete myself as a child, so it’s lovely to see them enjoying it just as much as I did.”

Alan Garnett – Senior Laboratory Scientist

“I’ve been working in veterinary diagnostics for over 40 years, and I still find it just as fascinating today as when I started. I spent the first 30 years of my career with the VI Service, VLA and AHVLA, before moving into Foods and Waters for a couple of years. When that chapter came to an end, I joined NationWide Laboratories, and eight years later, I’m still here, part of a brilliant team in microbiology. My role focuses on faecal bacteriology and parasitology, identifying pathogens in diagnostic samples and screening healthy animals, including those from zoos and exotic collections. It’s rewarding to know that what we do in the lab directly helps vets and nurses make the best decisions for animal health. I’ve always believed we’re all part of the same chain, different links, but working toward the same goal. I share my home with a cat and three dogs – life’s never quiet with that lot around! When I’m not surrounded by animals, you’ll probably find me at a music festival or a live gig. My girlfriend and I recently bought a caravan called Bertie, and we’re looking for forward to hitting the road for plenty of camping adventures.”

Antimicrobial Stewardship

Microbiology plays a crucial role in supporting antimicrobial stewardship. By identifying the specific pathogens present and testing their susceptibility to different antibiotics, the lab enables vets to make informed, targeted treatment decisions.

“Empirical treatment has its place,” explains Michelle, “but the more we can do to avoid unnecessary or inappropriate antibiotics, the better. Culture and sensitivity testing helps vets use the right drug, at the right dose, for the right duration.”

“We follow veterinary guidelines to provide breakpoints to ensure consistency and reliability. When we report sensitivity, we want it to reflect clinical relevance, not just lab performance.”

“We have also joined an antimicrobial stewardship working group – it’s a small group of clinicians and diagnostic laboratories all working together to improve antimicrobial stewardship. It looks at things such as standardising methodologies across the labs, and how we can make our reports and antibiotic choices easier for people to understand”

This commitment to responsible antimicrobial use not only protects current patients but also helps preserve antibiotic effectiveness for the future.

Quality Assurance in Microbiology

NationWide Laboratories runs internal quality control across all its microbiology procedures. Media is quality checked, control strains are run regularly, and any unusual findings are verified through repeat culture or additional tests. External quality assessments also ensure results are benchmarked against national standards.

“We run controls weekly, and we always check for unexpected growth,” says Michelle. “If something looks off, we don’t ignore it. We re-plate, we double-check, we investigate.”

Final Thoughts

Spending time with the microbiology team was both fascinating and reassuring. Their knowledge, skill, and care underpin the reports we rely on every day. They are not just processing samples, they are analysing, interpreting, questioning and confirming every result with clinical relevance in mind.

The next time you submit a culture or swab, remember: there’s a dedicated team working behind the scenes to ensure the answer you get back is not just accurate, but meaningful.

A Vet in the Lab: The People Behind the Process – Part 2 (Microbiology)