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Muscle condition in dogs score is assessed by visualization and palpation of the spine, scapulae, skull, and wings of the ilia.

Muscle loss is typically first noted in the epaxial muscles on each side of the spine; muscle loss at other sites can be more variable.

Muscle condition score is graded as normal, mild loss, moderate loss, or severe loss.

Note that animals can have significant muscle loss even if they are overweight (body condition score > 5/9). Conversely, animals can have a low body condition score (< 4/9) but have minimal muscle loss. Therefore, assessing both body condition score and muscle condition score on every animal at every visit is important.

Palpation is especially important with mild muscle loss and in animals that are overweight.

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Muscle condition score in cats is assessed by visualization and palpation of the spine, scapulae, skull, and wings of the ilia.

Muscle loss is typically first noted in the epaxial muscles on each side of the spine; muscle loss at other sites can be more variable.

Muscle condition score is graded as normal, mild loss, moderate loss, or severe loss.

Note that animals can have significant muscle loss even if they are overweight (body condition score > 5/9). Conversely, animals can have a low body condition score (< 4/9) but have minimal muscle loss. Therefore, assessing both body condition score and muscle condition score on every animal at every visit is important.

Palpation is especially important with mild muscle loss and in animals that are overweight.

PDF version is linked in the comments

Hyperkalaemia is the most life-threatening metabolic abnormality in cats with urethral obstruction due to its effects on cardiac conduction. Treatment is indicated if ECG abnormalities or bradycardia are present, or if serum potassium exceeds 7.0 mmol/L.

Intravenous fluids should be started immediately, with calcium gluconate administered to stabilise the myocardium. If urinary outflow cannot be rapidly restored, insulin with glucose can be used to temporarily lower serum potassium by shifting it intracellularly.

β₂-adrenergic agonists may be considered for persistent hyperkalaemia, although evidence in obstructed cats is limited. Prompt relief of the obstruction remains the definitive treatment.

Want to learn more about the pathophysiology of hyperkalemia? Comment "Hyperkalemia" and we’ll send you a paper that explains it in detail.

𝗗𝗶𝗽𝗵𝗲𝗻𝗵𝘆𝗱𝗿𝗮𝗺𝗶𝗻𝗲 𝗳𝗮𝗶𝗹𝗲𝗱 𝘁𝗼 𝗶𝗻𝗵𝗶𝗯𝗶𝘁 𝗲𝘅𝗽𝗲𝗿𝗶𝗺𝗲𝗻𝘁𝗮𝗹𝗹𝘆 𝗶𝗻𝗱𝘂𝗰𝗲𝗱 𝗰𝘂𝘁𝗮𝗻𝗲𝗼𝘂𝘀 𝗮𝗹𝗹𝗲𝗿𝗴𝗶𝗰 𝗿𝗲𝗮𝗰𝘁𝗶𝗼𝗻𝘀 𝗶𝗻 𝗵𝗲𝗮𝗹𝘁𝗵𝘆 𝗱𝗼𝗴𝘀, 𝘄𝗵𝗲𝗿𝗲𝗮𝘀 𝗰𝗲𝘁𝗶𝗿𝗶𝘇𝗶𝗻𝗲 𝘀𝗶𝗴𝗻𝗶𝗳𝗶𝗰𝗮𝗻𝘁𝗹𝘆 𝗿𝗲𝗱𝘂𝗰𝗲𝗱 𝗯𝗼𝘁𝗵 𝗶𝗺𝗺𝗲𝗱𝗶𝗮𝘁𝗲 𝗮𝗻𝗱 𝗹𝗮𝘁𝗲-𝗽𝗵𝗮𝘀𝗲 𝗿𝗲𝘀𝗽𝗼𝗻𝘀𝗲𝘀.

A randomized, double-blinded crossover study evaluated the pharmacodynamic effects of oral diphenhydramine and cetirizine on experimentally induced immediate- and late-phase cutaneous hypersensitivity reactions in healthy dogs.

Twelve healthy Beagle dogs were enrolled in a randomized, double-blinded crossover trial in which each dog served as its own control.

Dogs received:
• Diphenhydramine 2.2 mg/kg PO every 12 hours for six days
• Cetirizine 2 mg/kg PO every 12 hours for six days
with a two-week washout period between treatments.

Following treatment, intradermal injections of histamine and Compound 48/80 (a mast cell secretagogue) were administered. Immediate wheal-and-flare responses were assessed at 20 minutes, while late-phase inflammatory reactions were evaluated six hours after injection. Plasma antihistamine concentrations were also measured to confirm systemic drug exposure.

Results

Compared with baseline, cetirizine administration resulted in statistically significant reductions in:
• Histamine-induced wheal-and-flare reactions
• Compound 48/80-induced wheal responses
• Late-phase inflammatory reactions following both stimuli

In contrast, diphenhydramine did not significantly reduce either immediate or late-phase cutaneous responses despite achieving plasma concentrations considered therapeutically effective in human medicine.

Importantly, neither treatment produced clinically significant adverse effects or observable sedation during the study period.

These findings suggest that cetirizine provides substantially greater inhibition of experimentally induced histamine-mediated cutaneous reactions than oral diphenhydramine in healthy dogs.

Given that diphenhydramine is frequently administered to reduce histamine release associated with mast cell tumor manipulation, these results raise questions regarding its pharmacodynamic efficacy for this specific indication.

The authors conclude that, under the conditions evaluated, cetirizine should be preferred over oral diphenhydramine when suppression of histamine-mediated cutaneous reactions is the therapeutic objective.

Limitations
The study was performed in healthy laboratory dogs using an experimental intradermal challenge model. Consequently, these findings should not be directly extrapolated to dogs with naturally occurring allergic disease, urticaria, mast cell tumors, or anaphylaxis. Clinical efficacy in those patient populations remains to be established through appropriately designed clinical trials.

Study cited in the comments:

Should you vaccinate a cat with chronic kidney disease? What about one receiving prednisolone, cyclosporine, or chemotherapy?

The answer isn't always "yes" or "no."

This table provides a practical overview of how vaccination recommendations change depending on the underlying condition. In many cases, measuring feline panleukopenia virus (FPV) antibody titres before revaccination can help avoid unnecessary vaccines while ensuring adequate protection.

Some cats should be vaccinated as usual, others should have vaccination postponed, and for certain patients, the decision should be based on an individual risk-benefit assessment.

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Notes:

* To avoid unnecessary vaccination against feline panleukopenia virus (FPV) in case antibody levels are adequate
** Vaccination should be avoided even if no antibodies are present; therefore measuring FPV antibodies is not useful in this situation.
*** Depending on the situation, antibody measurement might be useful in adult cats that have to be vaccinated in this situation to avoid unnecessary vaccinations

Forgotten Facts About Medications #1: Clindamycin

As new evidence emerges and prescribing habits evolve, it's easy to overlook important pharmacologic details that can influence everyday clinical decision-making.

💡 Did you know?

Clindamycin accumulates within polymorphonuclear leukocytes (PMNs) and alveolar macrophages, where intracellular concentrations may exceed plasma concentrations by up to 50-fold.

It also penetrates the glycocalyx, including that associated with dental plaque and tartar, making it particularly useful in the management of many odontogenic infections.

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Not all pleural effusions are created equal. So we made a cheat sheet.

Distinguishing between a transudate, modified transudate, exudate, chylous effusion, and hemothorax can quickly narrow your differential diagnoses.

We turned the key diagnostic features into a one-page reference you can keep on your phone or print for your clinic.

Comment "Effusion" and we'll send you the PDF.

Some vaccines are not recommended for pet dogs because current evidence does not support their routine use.

These include:
• Canine enteric coronavirus (CCoV)
• Giardia duodenalis
• Microsporum canis (dermatophytosis)
• Killed (parenteral) canine parvovirus-2 vaccines where modified-live (MLV) vaccines are available

For example, CCoV is generally associated with mild disease in puppies, evidence that it causes significant intestinal disease in adult dogs is weak, and currently available vaccines have not been shown to protect against emerging pantropic strains. In addition, parenteral vaccination does not induce the intestinal IgA response needed for optimal protection.

Similarly, Giardia infection is typically treatable, rarely transmitted from dogs to humans, and current vaccines have not been shown to prevent infection or shedding. Vaccinated dogs may still develop clinical disease.

Although several of these vaccines are no longer widely available, they remain available in some countries. Veterinarians should be aware that current evidence does not support their routine use in pet dogs.

These recommendations are based on the 2024 World Small Animal Veterinary Association (WSAVA) Vaccination Guidelines developed by the Vaccination Guidelines Group (VGG) (Squires et al., 2024).

Not every mineral-opacity in the retroperitoneal space is a ureteral stone.

Abdominal radiographs can contain several normal anatomic structures and superimpositions that closely mimic disease. Recognizing these imaging pitfalls is an important part of radiographic interpretation and can help avoid unnecessary diagnostics or incorrect diagnoses.

This carousel explores one of the most common mimics encountered on abdominal radiographs. Swipe through the images and see if you would have recognized it before reaching the final slide.

📌 Keywords: veterinary radiology, abdominal radiographs, ureterolith, ureteral calculi, ureteral stones, deep circumflex iliac vessels, retroperitoneal fat, retroperitoneal anatomy, radiographic interpretation, diagnostic imaging, canine radiology, feline radiology.

Adapted from Vignoli M, Graham J. Atlas of Diagnostic Imaging of Dogs and Cats. Edra Publishing US LLC; 2022. Also from: Thrall & Robertson (2016) and Mühlbauer & Kneller (2013).

Hopefully you'll never need this cheat sheet. But if chemotherapy extravasation happens, you'll be glad you saved it.

Chemotherapy extravasation is an oncologic emergency. Prompt recognition and appropriate management can significantly reduce tissue injury and improve patient outcomes.

Not all chemotherapeutic agents are managed the same way after extravasation. Depending on the drug involved, the goal is to localize and neutralize, disperse and dilute, or simply monitor for mild inflammation.

Why cold for some drugs and warm for others? The answer lies in the drug's mechanism of tissue injury. Drugs like doxorubicin are best localized to prevent further spread, making cold compresses the preferred choice. In contrast, vinca alkaloids are better dispersed, so warm compresses and hyaluronidase help spread the drug and reduce its local concentration, minimizing tissue damage.

This infographic is based on the AAHA Chemotherapy Extravasation Management toolkit and is intended as a quick clinical reference. Always follow your institution's protocols and exercise clinical judgment when managing chemotherapy extravasation.

📄 VetEd Subscribers: A more comprehensive PDF guide, complete with additional explanations and dosages, will be posted in our subscriber group.