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Abstract Background Greyhounds have been reported to have hyperhomocysteinemia (HHC), but the underlying mechanisms and clinical implications are unclear. Hypothesis Our primary aim was to assess serum concentrations of homocysteine (HCy) and related analytes in Greyhounds and to identify a likely metabolic pathway for HHC. A secondary aim was to determine whether HHC is associated with evidence of oxidative stress. Animals Healthy pet Greyhounds (n = 31) and non‐sighthound control dogs (n = 15). Methods Analysis of serum HCy, cobalamin, folate, and methionine, and plasma cysteine, glutathione, and total 8‐isoprostane concentrations. Results Homocysteine concentrations were higher in Greyhounds (median, 25.0 μmol/L) compared to controls (13.9 μmol/L; P

Sighthounds, a distinctive group of hounds comprising numerous breeds, have their origins rooted in ancient artificial selection of dogs. In this study, we performed genome sequencing for 123 sighthounds, including one breed from Africa, six breeds from Europe, two breeds from Russia, and four breeds and 12 village dogs from the Middle East. We gathered public genome data of five sighthounds and 98 other dogs as well as 31 gray wolves to pinpoint the origin and genes influencing the morphology of the sighthound genome. Population genomic analysis suggested that sighthounds originated from native dogs independently and were comprehensively admixed among breeds, supporting the multiple origins hypothesis of sighthounds. An additional 67 published ancient wolf genomes were added for gene flow detection. Results showed dramatic admixture of ancient wolves in African sighthounds, even more than with modern wolves. Whole-genome scan analysis identified 17 positively selected genes (PSGs) in the African population, 27 PSGs in the European population, and 54 PSGs in the Middle Eastern population. None of the PSGs overlapped in the three populations. Pooled PSGs of the three populations were significantly enriched in "regulation of release of sequestered calcium ion into cytosol" (gene ontology: 0051279), which is related to blood circulation and heart contraction. In addition, ESR1 , JAK2 , ADRB1 , PRKCE , and CAMK2D were under positive selection in all three selected groups. This suggests that different PSGs in the same pathway contributed to the similar phenotype of sighthounds. We identified an ESR1 mutation (chr1: g.42,177,149 T > C) in the transcription factor (TF) binding site of Stat5a and a JAK2 mutation (chr1: g.93,277,007 T > A) in the TF binding site of Sox5. Functional experiments confirmed that the ESR1 and JAK2 mutation reduced their expression. Our results provide new insights into the domestication history and genomic basis of sighthounds. [ABSTRACT FROM AUTHOR]

Whippets are traditionally trained to compete in lure coursing. While in humans and horses, training is routinely monitored by special tests, this is not carried out in the training of whippets. The aim of this study was to check if laboratory tests designed for racehorses could be useful in monitoring whippets training for lure coursing.

Background: Greyhounds have been reported to have hyperhomocysteinemia (HHC), but the underlying mechanisms and clinical implications are unclear. Hypothesis: Our primary aim was to assess serum concentrations of homocysteine (HCy) and related analytes in Greyhounds and to identify a likely metabolic pathway for HHC. A secondary aim was to determine whether HHC is associated with evidence of oxidative stress. Animals: Healthy pet Greyhounds (n = 31) and non‐sighthound control dogs (n = 15). Methods: Analysis of serum HCy, cobalamin, folate, and methionine, and plasma cysteine, glutathione, and total 8‐isoprostane concentrations. Results: Homocysteine concentrations were higher in Greyhounds (median, 25.0 μmol/L) compared to controls (13.9 μmol/L; P <.0001). Cobalamin concentrations were lower in Greyhounds (median, 416 ng/L) compared to controls (644 ng/L; P =.004) and were inversely correlated with HCy (r = −0.40, P =.004). Serum concentrations of folate, which is regenerated when HCy is converted to methionine, also were inversely correlated with HCy (r = −0.47, P =.002). Serum methionine concentrations were more than 4‐fold lower in Greyhounds (median, 3.2 μmol/L) compared to controls (median, 15.0 μmol/L), but this difference was not significant (P =.3). Plasma cysteine, glutathione, and 8‐isoprostane concentrations did not differ significantly between groups. Conclusions and Clinical Importance: Our findings suggest a primary defect in conversion of HCy to methionine in Greyhounds, with related impaired folate generation. Ineffective cycling by methionine synthase could lead to secondary cobalamin depletion. Notably, low serum folate and cobalamin concentrations can be observed in Greyhounds without signs of intestinal disease. [ABSTRACT FROM AUTHOR]

Tazi is a Turkish sighthound breed that has not yet been officially recognized by the world canine organization - Fédération Cynologique Internationale (FCI). Research and analysis of morphometric parameters are required in order to write an official breed standard and recognize this breed. Previous research on this sighthound breed has shown only average values of individual morphological parameters and differences in them depending on gender, age or place of origin. However, the premise of this research is that there are several different varieties of Tazi, depending on the proportions of the body. Measurement results of 19 morphometric parameters showed that there are statistically significant differences between three sub-populations of Tazi, one with a format index greater than 100, the other with a format index less than 100 and third with a format index equal to 100. Such results are significant for setting the official breed standard in which the proportions of the body characteristic of this breed should be emphasized. [ABSTRACT FROM AUTHOR]

Bald thigh syndrome is a common hair loss disorder in sighthounds. Numerous possible causes, including environmental conditions, trauma, stress, endocrinopathies and genetic components have been proposed, but only endocrinopathies have been ruled out scientifically. The overall goal of our study was to identify the cause of bald thigh syndrome and the pathological changes associated with it. We approached this aim by comparing skin biopsies and hair shafts of affected and control dogs microscopically as well as by applying high-throughput technologies such as genomics, transcriptomics and proteomics. While the histology is rather unspecific in most cases, trichogram analysis and scanning electron microscopy revealed severe structural abnormalities in hair shafts of affected dogs. This finding is supported by the results of the transcriptomic and proteomic profiling where genes and proteins important for differentiation of the inner root sheath and the assembly of a proper hair shaft were downregulated. Transcriptome profiling revealed a downregulation of genes encoding 23 hair shaft keratins and 51 keratin associated proteins, as well as desmosomal cadherins and several actors of the BMP signaling pathway which is important for hair shaft differentiation. The lower expression of keratin 71 and desmocollin 2 on the mRNA level in skin biopsies corresponded with a decreased protein expression in the hair shafts of affected dogs. The genetic analysis revealed a missense variant in the IGFBP5 gene homozygous in all available Greyhounds and other sighthounds. Further research is required to clarify whether the IGFBP5 variant represents a predisposing genetic risk factor. We conclude from our results that structural defects in the hair shafts are the cause for this well-known disease and these defects are associated with a downregulation of genes and proteins essential for hair shaft formation. Our data add important knowledge to further understand the molecular mechanisms of HF morphogenesis and alopecia in dogs. [ABSTRACT FROM AUTHOR]

Dog sports competitions have greatly expanded. The availability of reference values for each type of activity could help assess fitness accurately. Heart rate (HR), blood lactate (BL) and rectal temperature (RT) are relevant physiological parameters to determine the dogs response to effort. Previous studies in greyhounds have reported the effect of high-intensity exercise on many physiological parameters immediately after completing different racing distances and recovery times. However, there are no studies concerning physiological changes over shorter racing distances. We therefore assessed the effect of sprint exercise on HR, BL and RT in nine greyhounds performing sprint exercise over a 100-m distance chasing a lure. After the exercise, dogs underwent a passive 10-min recovery phase. Before the exercise, immediately after it and at 5 and 10 min during recovery, HR and RT were assessed and blood samples were collected for BL determination. HR, BL and RT values increased significantly after the exercise (P<0.01). Whereas HR returned to pre-exercise values at 10 min during the recovery phase (P>0.1), BL concentration and RT remained increased (P<0.01). The abrupt increase in HR, BL and RT values observed immediately after the exercise indicates the high intensity of the effort performed. Similarly, BL concentration after the exercise exceeded the 4 mmol/L lactate threshold, suggesting a predominant anaerobic metabolism during effort. Although HR returned to pre-exercise values 10 min after the exercise, a more extensive recovery phase would be necessary for a total return to resting values, particularly for BL and RT. In greyhounds subjected to high-intensity exercise, HR, BL and RT were reliable physiological parameters to accurately assess the physiological response to effort. The use of sprint exercises over short racing distances could be useful for appropriately monitoring fitness in sporting dogs. [ABSTRACT FROM AUTHOR]

The Chippiparai dog, a unique medium-sized, sight-hound breed seen in south India, is studied to assess the distribution and breed characteristics. The breeding tract of this dog is Tirunelveli district of southern Tamil Nadu. The trademark features are fawn coat, black nostrils, black eyes, broad chest and tucked up abdomen. The overall means of body length, head length, muzzle length, tail length, height at withers, height at rump, chest girth, belly girth, ear length and ear width in adults were 60.90 ± 1.34, 21 ± 0.39, 9.56 ± 0.17, 40.28 ± 0.77, 59.56 ± 1.30, 59.84 ± 1.38, 60.36 ± 1.36, 39.30 ± 0.75, 10.92 ± 0.23 and 8.10 ± 0.18 cm respectively. Sex had significant effect (P< 0.05) on body length, and highly significant effect (P< 0.01) on height at withers and chest girth. This study shows that Chippiparai dog breed is a medium-sized indigenous sight hound dog of Tamil Nadu. [ABSTRACT FROM AUTHOR]

Objective-To assess use of serum thyroid hormone concentrations by veterinarians to diagnose hypothyroidism in sighthounds and to evaluate serum thyroid hormone concentrations in healthy Salukis. Design-Retrospective case series and cross-sectional study. Animals-398 sighthounds of various breeds with a diagnosis of hypothyroidism and 283 healthy Salukis. Procedures-Pretreatment thyroid hormone assay results from sighthounds subsequently classified as hypothyroid by practitioners were retrieved from a laboratory database. In healthy Salukis, serum concentrations of total thyroxine (T4), free T4, total triiodothyronine (T3), freeT3, and thyroid-stimulating hormone (TSH) and antibodies against thyroglobulin and thyroid hormones were assayed. Results-Records indicated hypothyroidism had been diagnosed in 303 (76.1%) sighthounds on the basis of low serum thyroid hormone concentrations alone and in 30 (7.5%) others despite all thyroid hormone indices being within reference limits. Only 65 116.3%) dogs had a high TSH concentration or positive thyroglobulin autoantibody result to support the diagnosis. In healthy Salukis, median (reference limits) serum concentrations of total T4, free T4, total T3, free T3, and TSH were 13.0 nmol/L (2.8 to 40.0 nmol/L), 12.0 pmol/L (2.0 to 30.3 pmol/L), 1.0 nmol/L (0.4 to 2.1 nmol/L), 4.0 pmol/L (1.6 to 77 pmol/L), and 0.18 ng/mL (0 to 0.86 ng/mL), respectively. Conclusions and Clinical Relevance-Diagnosis of hypothyroidism by practitioners was most often made without adequate supportive laboratory evidence. Thyroid hormone values in healthy Salukis differed markedly from standard reference limits for some, but not all, thyroid hormone indices. Breed-specific reference limits should be used when interpreting thyroid hormone profiles of sighthounds. [ABSTRACT FROM AUTHOR]

The article presents abstracts on veterinary medicine topics which include the criteria used to diagnose serum thyroid hormone in Salukis and hypothyroidism in sighthounds, the impact of general anesthesia on plasma colloid oncotic pressure in dogs, and the therapeutic use of leflunomide for immune-mediated polyarthritis in dogs.