We are pleased to present our newsletter of the month. As animal health professionals, you are aware of the vital importance of good oral hygiene to the overall health of your patients. Dental conditions are one of the most common health problems in dogs and cats, and can lead to chronic pain and bad breath, on which ones we'll be focusing on in this issue.   

In this latest blog, we will provide you with information on the causes of halitosis, as well as the preventive measures you can recommend to your customers to prevent this problem in their pets.  

We are convinced that this newsletter will provide you with useful information to help your customers keep a close eye on their pets' oral health. We hope you will find it both informative and beneficial to your daily practice.  

Enjoy your reading!  

Quote of the month: "Smiling three times every day makes any medication unnecessary".  Chinese proverb  

Literature review: halitosis in dogs and cats: causes and prevention  

Halitosis is a common complaint in dogs and cats that can cause real discomfort for owners and alter the relationship they have with their pets. In this article, we explore the causes and potential consequences of halitosis in our domestic carnivores, as well as ways of preventing the condition.  

Origin of halitosis  

Halitosis can have a systemic origin1: in chronic kidney disease, the lack of glomerular filtration leads to the accumulation of metabolic waste in the blood, which can make the breath smell like urine or ammonia. In the case of diabetes mellitus, ketosis can lead to fruity breath. Gastrointestinal disorders such as intestinal obstruction or vomiting can also alter the smell of breath, to name but a few examples.   

However, the most common cause of halitosis in domestic carnivores is oral2 .   

 

Etiology of oral halitosis: proteins from food debris, gingival bleeding, desquamated epithelial cells, tissue necrosis, etc. are metabolised by Gram-negative anaerobic bacteria present in the oral cavity and saliva. This metabolism generates volatile sulphur compounds (VSCs), such as methyl mercaptan, hydrogen sulphide and dimethyl sulphide, which are the main contributors to unpleasant breath odour.  

In addition, the bacteria responsible for the formation of VSC can metabolise certain sulphur-containing amino acids present in saliva and food to produce diamines such as putrescine and cadaverine, which are also responsible for the unpleasant odour3.  

The degree of halitosis is strongly correlated with the concentration of VSCs and diamines  

Consequences of halitosis 4,5 

The main risk associated with the presence of VSCs and diamines in the oral cavity is inflammation, with its attendant complications. In addition, the alkaline salivary pH of carnivores (around 8.5 in dogs, compared with a normal pH range of 6.2-7.6 in humans) is conducive to the growth of bacterial species known to be associated with certain inflammatory processes in the oral cavity.  

  • VSCs increase the permeability of the oral mucosa, allowing endotoxins and prostaglandins to penetrate the tissue barrier. This situation exposes the animal to the development of periodontal disease, which in turn deepens periodontal pockets and exacerbates bacterial colonisation and halitosis.  
  • Diamines can be used as an energy source for the anaerobic bacteria that produce them, as well as for other bacteria present in the bacterial biofilm. These diamines can also promote the strength and anchorage of the biofilm on teeth by helping to bind the bacteria together in the biofilm, making them more resistant to antimicrobial agents and immune system attacks.  
  • The change in the microbiome in the event of inflammation further intensifies the production of VSCs and increases the quantity and quality of substrate available for putrefaction by anaerobic bacteria, which only makes the situation worse.   

Did you know that halitosis can be transmitted? A study concludes that pets can transmit the bacteria responsible for bad breath to their owners6 .   

More worryingly, another study indicates that dental plaque can be a source and reservoir of antibiotic-resistant bacteria, and that antibiotic resistance genes could be exchanged between humans and pets living under the same roof7 .   

 

Ways of preventing halitosis in dogs and cats   

Preventing halitosis linked to dental hygiene is first and foremost a matter of educating the owner2. According to one study, most dog owners believe that home dental care is important, but less than 4% of them say they brush their dog's teeth every day8.

In addition to regular tooth brushing, other specific products for the oral hygiene of dogs and cats are available on the market and can be recommended, such as gels, drinking solutions, specific dental foods or chewable dental sticks to help reduce plaque build-up and prevent bad breath9 .   

 

Bibliography  

Niemiec B, Gawor J, Nemec A, Clarke D, McLeod K, Tutt C, Gioso M, Steagall PV, Chandler M, Morgenegg G, Jouppi R. World Small Animal Veterinary Association Global Dental Guidelines. J Small Anim Pract. 2020 Jul;61(7):E36-E161. doi: 10.1111/jsap.13132. Erratum in: J Small Anim Pract. 2020 Dec;61(12):786. PMID: 32715504.  

Culham N, Rawlings JM. Oral malodor and its relevance to periodontal disease in the dog. J Vet Dent. 1998 Dec;15(4):165-8. doi: 10.1177/089875649801500401. PMID: 10518872.  

Milella L. The Negative Effects of Volatile Sulphur Compounds. J Vet Dent. 2015 Summer;32(2):99-102. doi: 10.1177/089875641503200203. PMID: 26415386.  

Barko, P. Halitosis. In: BSAVA Manual of Canine and Feline Gastroenterology, 11: 60-63. Gloucester: British Small Animal Veterinary Association, ©2020. DOI: 10.22233/9781910443361-3e.11  

Croft JM, Patel KV, Inui T, Ruparell A, Staunton R, Holcombe LJ. Effectiveness of oral care interventions on malodour in dogs. BMC Vet Res. 2022 May 5;18(1):164. doi: 10.1186/s12917-022-03267-8. PMID: 35513817; PMCID: PMC9074277.  

Iwanicka-Grzegorek E, Kepa J, Lipkowska E, Michalik J, Pierzynowska E, Placha R. Is transmission of bacteria that cause halitosis from pets to humans possible? Oral Dis. 2005;11 Suppl 1:96-7. doi: 10.1111/j.1601-0825.2005.01104.x. PMID: 15752112.  

Pérez-Serrano RM, Domínguez-Pérez RA, Ayala-Herrera JL, Luna-Jaramillo AE, Zaldivar-Lelo de Larrea G, Solís-Sainz JC, García-Solís P, Loyola-Rodríguez JP. Dental plaque microbiota of pet owners and their dogs as a shared source and reservoir of antimicrobial resistance genes. J Glob Antimicrob Resist. 2020 Jun;21:285-290. doi: 10.1016/j.jgar.2020.03.025. Epub 2020 Apr 18. PMID: 32315776.  

Enlund KB, Brunius C, Hanson J, Hagman R, Höglund OV, Gustås P, Pettersson A. Dental home care in dogs - a questionnaire study among Swedish dog owners, veterinarians and veterinary nurses. BMC Vet Res. 2020 Mar 18;16(1):90. doi: 10.1186/s12917-020-02281-y. PMID: 32188446; PMCID: PMC7081671.  

Di Cerbo A, Pezzuto F, Canello S, Guidetti G, Palmieri B. Therapeutic Effectiveness of a Dietary Supplement for Management of Halitosis in Dogs. J Vis Exp. 2015 Jul 6;(101):e52717. doi: 10.3791/52717. PMID: 26167807; PMCID: PMC4545009.