Table 3. Phage therapy in companion animal industry

Animals	Target bacteria	Symptoms	Phage application	Therapeutic activity	References
Canine	P. aeruginosa	Otitis media	Pa12, Pa18	This study explored two sewage-derived phages capable of lysing a variety of P. aeruginosa strains, even those resistant to fluoroquinolones. Notably, the phages showed effectiveness against isolates with high enrofloxacin and orbifloxacin resistance.	[78]
	P. aeruginosa		Phage cocktail	A bacteriophage treatment for chronic P. aeruginosa otitis in 10 dogs resulted in a significant improvement within 48 h, with a mean clinical score fall of 30.1% and a mean P. aeruginosa count fall of 67%.	[77]
	E. coli (UPEC)	Urinary tract infections	Single phage	Bacteriophages effectively lysed 94% of UPEC strains, with 10 of them individually lysing ⩾51% of the strains.	[79]
	S. pseudintermedius (MRSP)	Skin infections	Single phage	All phages (n = 4) successfully lysed all MRSP isolates (n = 17); however, their lytic activity was restricted to S. pseudintermedius and S. schleiferi.	[80]
	Staphylococcus spp. (MDR)	Conjunctivitis	Single phage	The phage eye drops tested in the experiment demonstrated 100% effectiveness in vitro against the Staphylococcus isolates under investigation.	[133]
	L. infantum	Visceral leishmaniasis	CVL serodiagnosis	This study found eight mimotopes for accurate CVL serodiagnosis using a cost-effective and straightforward phage-ELISA assay.	[83]
Feline	E. coli (UPEC)	Urinary tract infections	Single phage	Bacteriophages effectively lysed 94% of UPEC strains, with 10 of them individually lysing ⩾51% of the strains.	[79]

In the companion animal industry, various studies have been conducted to address the prevalent issue of pathogenic bacteria and bacterial diseases, using bacteriophages for prevention. The use of phages in the companion animal industry is relatively limited compared with livestock, but it is predicted that more research will be conducted in the future. The “Phage application” section provides information on the names or numbers of phages used in the treatment.
P. aeruginosa, Pseudomonas aeruginosa; E. coli, Escherichia coli; UPEC, UroPathogenic Escherichia coli; L. infantum, Leishmania infantum.