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Objectives To identify bacterial microorganisms associated with canine keratomalacia, review their antimicrobial sensitivity, and evaluate clinical outcomes compared to results of microbial culture. Methods Retrospective analysis of clinical records of dogs diagnosed with a melting corneal ulcer presented to a referral hospital in Hertfordshire, UK between 2014 and 2018. Results One hundred and ten melting corneal ulcers were sampled in 106 dogs. The most common pure bacterial isolate was Pseudomonas aeruginosa (n = 26) followed by β-hemolytic Streptococcus (n = 12). Melting corneal ulcers that cultured coagulase-positive Staphylococcus, coliform bacteria, Pasteurella multocida, Enterococcus, and Streptococcus viridans presented in smaller numbers and were analyzed together (n = 16). Multiple cultures were identified in nine cases (n = 9). Forty-seven cultures yielded no bacterial growth (n = 47). The susceptibility to fluoroquinolones remained high with the exception of β-hemolytic Streptococci. There was no significant difference in the ulcer severity at presentation in regard to the cultured bacteria. Overall, 63 eyes (57%) received surgical grafting in addition to medical treatment. In 14 cases (13%), the progression of corneal melting despite medical ± surgical treatment resulted in enucleation. Fifty-seven percent (8/14) of the enucleated eyes cultured pure Pseudomonas aeruginosa isolates. In contrast, all β-hemolytic Streptococcus-associated ulcers healed. Conclusions The most common bacterial species associated with canine keratomalacia were Pseudomonas aeruginosa and β-hemolytic Streptococcus. Because of the variation in antibacterial sensitivity between these two species, bacterial culture and sensitivity testing should be performed in all dogs presenting with keratomalacia. Melting corneal ulcers associated with pure Pseudomonas infection were significantly more likely to result in globe loss than melting corneal ulcers associated with other cultures.

The domestic cat is one of the most popular pets in the world. It is estimated that 89–92% of domestic cats in the UK are non-pedigree Domestic shorthair (DSH), Domestic longhair (DLH), or Domestic semi-longhair cats (DSLH). Despite their popularity, little is known of the UK non-pedigree cats’ population structure and breeding dynamics. Using a custom designed single nucleotide variant (SNV) array, this study investigated the population genetics of 1344 UK cats. Principal components analysis (PCA) and fastSTRUCTURE analysis verified that the UK’s DSH, DLH, and DSLH cats are random-bred, rather than admixed, mix breed, or crossbred. In contrast to pedigree cats, the linkage disequilibrium of these random-bred cats was least extensive and decayed rapidly. Homozygosity by descent (HBD) analysis showed the majority of non-pedigree cats had proportionally less of their genome in HBD segments compared to pedigree cats, and that these segments were older. Together, these findings suggest that the DSH, DLH, and DSLH cats should be considered as a population of random-bred cats rather than a crossbred or pedigree-admixed cat. Unexpectedly, 19% of random-bred cat genomes displayed a higher proportion of HBD segments associated with more recent inbreeding events. Therefore, while non-pedigree cats as a whole are genetically diverse, they are not impervious to inbreeding and its health risks.

One of the primary objectives of the Oncology-Pathology Working Group (OPWG), a joint initiative of the Veterinary Cancer Society and the American College of Veterinary Pathologists, is for oncologists and pathologists to collaboratively generate consensus documents to standardize aspects of and provide guidelines for oncologic pathology. Consensus is established through critical review of peer-reviewed literature relevant to a subgroup's particular focus. Subsequent acceptance and approval of the document by the OPWG membership at large establishes consensus. The intent of this publication is to help educate practitioners and pathologists on the value of diagnostics related to the KIT receptor tyrosine kinase for canine cutaneous mast cell tumours and to provide a guide for the use of these tests in veterinary medicine. This document represents the opinions of the OPWG and the authors and does not constitute a formal endorsement by the American College of Veterinary Pathologists or the Veterinary Cancer Society.

Hypermanganesemia is commonly recognized in human patients with hepatic insufficiency and portosystemic shunting. Since manganese is neurotoxic, increases in brain manganese concentrations have been implicated in the development of hepatic encephalopathy although a direct causative role has yet to be demonstrated. Evaluate manganese concentrations in dogs with a naturally occurring congenital shunt before and after attenuation as well as longitudinally following the changes in hepatic encephalopathy grade. Our study demonstrated that attenuation of the shunt resolved encephalopathy, significantly reduced postprandial bile acids, yet a hypermanganasemic state persisted. This study demonstrates that resolution of hepatic encephalopathy can occur without the correction of hypermanganesemia, indicating that increased manganese concentrations alone do not play a causative role in encephalopathy. Our study further demonstrates the value of the canine congenital portosystemic shunt as a naturally occurring spontaneous model of human hepatic encephalopathy.

Summary In morphological terms, “form” is used to describe an object’s shape and size. In dogs, facial form is stunningly diverse. Facial retrusion, the proximodistal shortening of the snout and widening of the hard palate is common to brachycephalic dogs and is a welfare concern, as the incidence of respiratory distress and ocular trauma observed in this class of dogs is highly correlated with their skull form. Progress to identify the molecular underpinnings of facial retrusion is limited to association of a missense mutation in BMP3 among small brachycephalic dogs. Here, we used morphometrics of skull isosurfaces derived from 374 pedigree and mixed-breed dogs to dissect the genetics of skull form. Through deconvolution of facial forms, we identified quantitative trait loci that are responsible for canine facial shapes and sizes. Our novel insights include recognition that the FGF4 retrogene insertion, previously associated with appendicular chondrodysplasia, also reduces neurocranium size. Focusing on facial shape, we resolved a quantitative trait locus on canine chromosome 1 to a 188-kb critical interval that encompasses SMOC2. An intronic, transposable element within SMOC2 promotes the utilization of cryptic splice sites, causing its incorporation into transcripts, and drastically reduces SMOC2 gene expression in brachycephalic dogs. SMOC2 disruption affects the facial skeleton in a dose-dependent manner. The size effects of the associated SMOC2 haplotype are profound, accounting for 36% of facial length variation in the dogs we tested. Our data bring new focus to SMOC2 by highlighting its clinical implications in both human and veterinary medicine., Highlights • A population-based genetics study of dogs that required diagnostic imaging • Resolution of a QTL associated with face length reduction (brachycephaly) • Association of brachycephaly with a retrotransposon that disrupts SMOC2 splicing • The SMOC2 locus explains up to 36% of face length variation in dogs, Uncovering the molecular basis of dogs’ vastly diverse skull shapes requires individualized approaches to morphometrics and genotyping. Using data from veterinary referral patients, Marchant et al. shed light on a large effect locus that is responsible for face length reduction (brachycephaly).