Two-dimensional grayscale ultrasound and spectral Doppler waveform evaluation of dogs with chronic enteropathies

Sonography is an important diagnostic tool to examine the gastrointestinal tract of dogs with chronic diarrhea. Two-dimensional grayscale ultrasound parameters to assess for various enteropathies primarily focus on wall thickness and layering. Mild, generalized thickening of the intestinal wall with maintenance of the wall layering is common in inflammatory bowel disease. Quantitative and semi-quantitative spectral Doppler arterial waveform analysis can be utilized for various enteropathies, including inflammatory bowel disease and food allergies. Dogs with inflammatory bowel disease have inadequate hemodynamic responses during digestion of food. Dogs with food allergies have prolonged vasodilation and lower resistive and pulsatility indices after eating allergen-inducing foods.     

Doppler velocimetric parameters of the testicular artery in healthy dogs

This study aimed to examine the Doppler velocimetric pattern of the testicular artery of small dogs in two different locations. Testes of 21 dogs were evaluated by two-dimensional ultrasonography to measure testicular volume and by Doppler ultrasonography to record the velocimetric patterns of the testicular artery in the spermatic cord and marginal location. The volume of left testes (4.70 ± 1.22 cm³) was significantly higher than the volume of the right testes (4.45 ± 1.17 cm³). Peak systolic velocity (PSV) of the left spermatic cord was significantly higher than the right side. End-diastolic velocity was significantly higher in the marginal artery than the spermatic cord on both sides; however, resistance and pulsatility indexes were significantly lower in the marginal artery. Results demonstrate the viability of Doppler ultrasonography for characterization of the testicular artery in small dogs and Doppler velocimetric values vary according to the location of measurement along the artery.     

Evaluation of the use of SYBR-14 and propidium iodide stain in a fluorescent computer-assisted spermatozoal quantification method in dogs

The aim of this study was to evaluate the use of SYBR-14/propidium iodide (PI) stain in a computer-assisted spermatozoal quantification (CASQ) method of determining spermatozoal concentration in canine semen. In Experiment A, the spermatozoal concentration was measured (n = 52) with a haemocytometer and by CASQ under fluorescent illumination using green long-pass (G-LP) and red long-pass filters at measurement concentrations of <25 million/ml. For the red filter, the limits of agreement between the haemocytometer and CASQ were −6.3% to 6.8% and −7.5% to 6.2% between the haemocytometer and CASQ for the G-LP filter. For the red filter, the mean precision CVs were 2.21% ± 4.33% (mean ± 95% CI) for the haemocytometer, 2.19% ± 4.29% for CASQ and using the G-LP filter 2.13% ± 4.18% for the haemocytometer and 2.66% ± 5.21% for CASQ. In Experiment B, spermatozoa were also examined with a green spectrum short-pass (G-SP) filter (n = 50) at measurement concentrations of <12.5 million/ml. The limits of agreement between the haemocytometer and CASQ were −5.4% to 7.8% using the red filter, −15.8% to 14.3% using the G-LP filter and −13.1% to 11.3% using the G-SP filter. The mean precision CVs for the haemocytometer and CASQ, respectively, were 2.68% ± 5.26% (mean ± 95% CI) and 1.93% ± 3.72% using the red filter and 2.01% ± 3.95% and 3.55% ± 6.95% using the G-LP filter, and 3.96% ± 7.76% for CASQ using the G-SP filter. Using the red filter, the agreement between the haemocytometer and CASQ and the precision of both haemocytometer methods and CASQ were better than when using green filters. The CASQ method performed using green filters produced acceptable results; however, CASQ using a red filter with PI staining alone was superior to that using green filters and SYBR-14/PI staining.     

Development of a fluorescent computer‐assisted spermatozoal quantification method and a comparison of results for manual counting with a haemocytometer and computer‐assisted semen analysis in dogs

The aim of this study was to develop and validate a novel, computer‐assisted spermatozoal quantification (CASQ) method of determining spermatozoal concentration in canine semen. In Experiment A, the spermatozoal concentration was measured (n = 28) with a haemocytometer using light microscopy, CASQ and computer‐assisted semen analysis (CASA; MMC sperm), following three independent dilutions. The limits of agreement between the haemocytometer and CASQ were ?13.1% to 13.8% and ?27.0% to 28.6% between the haemocytometer and CASA. The precision CVs (limits of agreement) were 5.7% (?7.8% to 8.9%) for the haemocytometer, 6.2% (?8.8% to 12.3%) for CASQ and 10.8% (?16.0% to 19.5%) for CASA. In Experiment B, spermatozoa were manually counted (n = 42) with the haemocytometer under fluorescent illumination using the CASQ sample. The limits of agreement between the CASQ and the haemocytometer were satisfactory (?4.6% to 4.6%) and the precision CVs (limits of agreement) were 6.2% (?9.0% to 11.4%) for the haemocytometer and 4.4% (?5.8% to 8.6%) for CASQ. The CASQ method was then clinically applied to compare the haemocytometer (light and fluorescent methods) with CASQ and CASA. Outlying data were removed. These studies demonstrated that CASQ was reliable and that the MMC sperm CASA was unreliable as methods for determining spermatozoal concentration in canine semen. Computer‐assisted spermatozoal quantification was also determined to be more precise than manual counting with the haemocytometer. Using the clinical protocol, the agreement between the haemocytometer and CASQ method was acceptable, but it was worse than in the experiments where duplicate samples and a larger volume of semen were analysed. The CASQ method may be a useful method to measure the membrane status of canine spermatozoa; however, further investigation is required. Counting spermatozoa using fluorescent microscopy and the haemocytometer may improve the efficiency of counting and the accuracy of the method.     

Colour Doppler ultrasound imaging of blood flows variations in neoplastic and non‐neoplastic testicular lesions in dogs

Testicular tumours are the most common neoplasms in male dogs accounting for approximately 90% of all tumours affecting the genitourinary tract. Gray‐scale ultrasonography in combination with colour and power Doppler imaging has been well accepted as an accurate technique for assessing scrotal lesions and vascularization of the testis. Colour Doppler sensitivity for low blood flows appears promising in the study of testicular disorders. The aim of this study was to assess if colour and power Doppler ultrasound is a good tool for the investigation of testicular lesions in dogs, to report the sonographic features of lesions and to measure colour and power Doppler parameters such as resistive index (RI), pulsatility index (PI), hypovascularization and hypervascularization (VI) determining if they can be used to distinguish testicular neoplasms from the wide spectrum of non‐neoplastic pathological findings. In this study, 50 male dogs of various breeds, aged between 7 and 14 years, presented with testicular disorders were selected. RI and PI were calculated. Mean RI values for neoplastic, inflammatory and degenerative lesions were 0.54, 0.45 and 0.58, respectively. Mean PI values were 0.62, 0.55 and 0.63, respectively. Hypovascularization and hypervascularization of the lesion were evaluated throughout the vascularity index (VI). Vascular signals in neoplasms were significantly intensified around and inside the mass if compared with those measured during inflammatory and degenerative lesions. VI markedly increased in solid tumours. Pathological testes were removed; macroscopical, histological and immunoistochemical evaluations were carried out. Colour Doppler showed increased intralesional and peripheral flows in all neoplastic lesions analysed. No flows were detected around cysts.     

The evaluation of lycopene and cysteamine supplementation effects on sperm and oxidative stress parameters during chilled storage of canine semen

The aim of this study was to evaluate the effects of different concentrations of lycopene and cysteamine on characteristics of sperm, liquid peroxidation and enzymatic activities in seminal plasma of canine semen preserved at 5°C for 72 hr. The semen samples were divided into eight aliquots: control, control sham (dimethyl sulfoxide 5%), lycopene groups (250, 500 and 750 µg/ml) and cysteamine groups (2.5, 5 and 10 mM). Motility, viability, membrane integrity, DNA integrity, total antioxidant capacity (TAC) and malondialdehyde (MDA) levels were evaluated. Progressive motility and total motility were higher with the 500 and 750 µg/ml lycopene concentrations, respectively, compared to the control group and the cysteamine groups following 72 hr of storage in the liquid storage. Motility characteristics, viability and hypo-osmotic swelling test (HOST) percentages were significantly improved in 500 µg/ml lycopene compared to other groups. The 500 and 750 µg/ml lycopene concentrations, respectively, showed significantly reduced percentages of spermatozoa with DNA integrity compared to the control group. The 500 and 750 µg/ml lycopene concentrations, respectively, led to the significant decrease of MDA levels. The 500 µg/ml lycopene enhanced TAC levels after 48 and 72 hr that was not observed in other groups. In conclusion, the findings of this study showed that lycopene supplementation in canine semen extenders improved canine semen parameters and TAC levels and decreased MDA levels in the chilling process.     

柠檬酸对小鼠精子特性和睾丸组织形态结构的影响

60只雄性小鼠随机分为4组,每天分别腹腔注射0.2mL的0.9%生理盐水或7.5、15、30g/L CA,于14、21d测定曲细精管精子的生成及附睾内精子特性的相关数据。结果显示,随柠檬酸处理剂量的增加精子的生成数减少。14d时,对照组与15、30g/L CA组间、7.5、30g/L CA组间曲细精管内精子的生成差异显著（P〈0.05）;21d时,对照组与柠檬酸处理组间及7.5、15g/L CA与30g/L CA处理组间曲细精管内精子的生成有显著差异（P〈0.05）。柠檬酸对附睾精子品质的影响表现为：对照组与柠檬酸处理组间及柠檬酸处理组间精子密度和活动率差异均显著（P〈0.05）;对照组和15、30g/L CA处理组及15g/L CA与30g/L CA处理组间精子活力差异显著（P〈0.05）;精子的畸形率随柠檬酸浓度的增加而增加,15g/L CA处理组精子畸形率显著高于对照组（P〈0.05）,30g/LCA处理组显著高于对照组和7.5g/L CA（P〈0.05）处理组。组织形态学观察结果表明柠檬酸能破坏睾丸正常组织形态结构。柠檬酸高剂量组的生精小管内生精细胞排列疏松、紊乱,生精细胞间出现空隙;生精小管中的生精细胞脱落或退化,精原细胞、精母细胞和精子数量明显减少。研究表明,外源柠檬酸雄性小鼠具有显著的生殖遗传毒性。     

Assessment of cardiac troponin I (cTnI) and tissue velocity imaging (TVI) in 14 dogs with malignant lymphoma undergoing chemotherapy treatment with doxorubicin

Doxorubicin has been shown to be cardiotoxic at high doses but is an efficacious chemotherapeutic agent in the treatment of canine lymphoma. Echocardiographic measurements and serum ultrasensitive cardiac troponin I (cTnI) levels were obtained before and after doxorubicin administration in 14 dogs diagnosed with lymphoma. The aim of this prospective study was to evaluate changes in cTnI concentrations and tissue velocity imaging (TVI) values in dogs with lymphoma undergoing chemotherapy with doxorubicin. A total of 182 cTnI and 1017 TVI measurements were performed. Standard echocardiographic parameters, tissue Doppler indices and cTnI concentrations did not differ at any time point within a 12‐week cyclic combination protocol. In conclusion, the use of doxorubicin at standard doses in the treatment of canine lymphoma may not be associated with significant myocardial damage.     

Color and power Doppler ultrasonography for characterization of splenic masses in dogs

Benign and malignant splenic masses can appear similar on B-mode imaging, making ultrasound sensitive but not specific in their diagnosis. Our goal was to characterize color and/or power Doppler characteristics of vasculature within and adjacent to a splenic mass, which would distinguish benign vs. malignant lesions. The hypothesis was that malignant splenic masses will have altered vascular patterns compared with benign masses. Color and power Doppler cineloops evaluating the vasculature within the mass and normal splenic parenchyma were obtained in sagittal and transverse planes using a standardized protocol. Categories of evaluation included presence of peritoneal effusion, a large aberrant or tortuous vessel within the mass, relative blood flow within the mass compared with normal parenchyma, and path of vessels in the adjacent parenchyma entering into the mass. All patients had histopathologic or definitive cytologic diagnosis. Thirty-one dogs were included. There were 13 malignant masses and 18 were benign. Peritoneal effusion was significantly associated with malignancy (P = 0.0007). Presence of an aberrant or tortuous vessel within the mass was nearly significant (P = 0.059). There was no significant difference in any of the color or power Doppler blood flow evaluations. Ultrasonographic findings of a splenic mass and peritoneal effusion may indicate malignancy. The presence of an aberrant vessel within a splenic mass could suggest malignancy; however more data are needed.     

Semen parameters and testicular dimensions in small breed dogs below ten‐kilogram bodyweight

Because of few available data on semen parameters in small breed dogs, the study aimed to analyse semen and measure testes of dogs ≤10.0 kg bodyweight. Semen was collected from 41 fertile stud dogs, which were divided based on bodyweight: group 1 ≤ 5.0 kg and group 2 between 5.1 and 10.0 kg. Median values for ejaculate volume (group 1: 1.2 ml; group 2: 2.2 ml), total sperm output (group 1: 110.7 × 10⁶; group 2: 215.1 × 10⁶) and testicular volume (group 1: left testicle 2.8 ml, right testicle 2.7 ml; group 2: left testicle 5.5 ml, right testicle 5.0 ml) were lower in group 1 compared to dogs of group 2 (p = .001; p = .001; both testes: p < .001). There was no difference in sperm concentration (p = .985). Based on these results, introduction of an additional weight group to the commonly used reference values is recommended, since values for ejaculate volume, total sperm output and testicular dimensions for dogs ≤5.0 kg bodyweight differed significantly from values of dogs with a bodyweight from 5.1 to 10.0 kg.     

Hematological and splenic Doppler ultrasonographic changes in dogs sedated with acepromazine or xylazine

Objective

To evaluate the onset and duration of hematological changes and the use of Doppler ultrasound (spleen) in dogs sedated with acepromazine or xylazine.

Comparative Doppler imaging of the ophthalmic vasculature in normal Beagles and Beagles with inherited primary open-angle glaucoma

The objective of this study was to compare orbital and ocular vasculature velocity, measured by Doppler imaging, in normal Beagles and Beagles with inherited primary open-angle glaucoma. Eight normal Beagles and 13 Beagles with different stages of primary open-angle glaucoma were evaluated twice with a 2–4-week period between measurements. Doppler imaging was performed with the dogs anesthetized, and the Doppler transducer applied directly on the corneal surface. The majority of the orbital vasculature (external ethmoidal artery; internal ophthalmic artery and vein; and external ophthalmic artery and vein) and ocular blood vessels (anterior ciliary artery and veins; long posterior ciliary arteries; short posterior ciliary arteries; primary retinal arteries; and the vortex veins) were identified and Doppler blood velocity parameters were determined. The glaucomatous dogs demonstrated significant differences in the Doppler velocity parameters of several orbital vessels (external ethmoidal, external ophthalmic, and internal ophthalmic arteries), and several ocular vessels (anterior ciliary, short posterior ciliary, and long posterior ciliary arteries). These differences included decreased blood velocities, and increased pulsatility and resistive indexes. The Doppler blood flow velocities of the primary retinal arteries were unchanged between the normal and glaucomatous dogs. In the glaucomatous dogs, the Doppler imaging suggests increased vascular resistance downstream in both the orbital and ocular vasculature. These blood velocity parameter changes may be primary or secondary, and may offer therapeutic opportunities to increase perfusion, prolong the retina and optic nerve head function, and maintain vision in the canine glaucomas.     

Comparison of behavioral characteristics of dogs in the United States and Japan

This study examined the difference in dog owning between Japan and the United States, and the effect of these differences on dogs’ behavioral characteristics. Behavioral evaluations of privately-owned dogs were obtained by using online questionnaire. We compared background and demographic information from the two countries and analyzed the effects of these differences on behavioral characteristics in dogs. The results indicated that there was a bias in the dog breeds kept in Japan compared to the United States and that Japanese dogs’ body weight was lower than the US dogs. The main source of dog acquisition was pet stores in Japan and breeders and/or shelters in the United States. Multiple linear regression analysis found that Japanese dogs showed more aggression to household members and higher energy, restlessness and fear of non-social stimuli than US dogs, while US dogs showed more fear of unfamiliar persons, separation-related behavior and excitability. US dogs also showed higher levels of trainability and attachment to owners. The lower dog’s body weight was, the higher the behavioral scores except for trainability were. When dogs that were obtained under 3 months of age were analyzed, the younger the dogs were when their owners obtained them, the higher the scores on some behavioral problem factors were. The higher rates of problem behaviors among Japanese dogs compared with US dogs suggest that the preference for small breed dogs and poor early development environment influenced the behavioral characteristics of dogs.     

Histological and immunohistochemical characteristics of cerebral amyloid angiopathy in elderly dogs

Background: Cerebral amyloid angiopathy (CAA) is a disorder characterized by amyloid deposition in the wall of cerebral blood vessels. The deposits of amyloid occur frequently in the blood vessels of the frontal, parietal and occipital cortex.

Objective: To examine the characteristics of CAA classified according to the Vonsattel scale in elderly dogs histologically and immunohistochemically as well as the semi-quantitative evaluation of the amyloid deposits in the different segments of the brain.

Animals and methods: The brains of 36 dogs of different breeds and sexes, which had been routinely necropsied, were used and divided into two groups: dogs from 1 to 5 and 10 to 18 years old. The tissue sections were stained by hematoxylin–eosin, Congo red and immunohistochemically.

Results: Amyloid was accumulated in the wall of cerebral blood vessels in 70% of dogs over the age of 10 years predominantly in the frontal cortex. CAA was demonstrated in elderly dogs as follows: in the frontal cortex (n = 19 or 63%), the parietal cortex (n = 12 or 40%), the hippocampus (40%) and the cerebellum (n = 5 or 17%). The deposits of amyloid in the wall of blood vessels detected by Congo red staining were also Aβ1-14 and Aβ1-42 immunohistochemically positive. Most commonly, the amyloid deposits affected a moderate number of blood vessels. The accumulation of amyloid was immunohistochemically revealed in the blood vessel walls as well as in the senile plaques and neurons.

Conclusion: The amount of amyloid in the arterial walls increased with age in dogs, whereas the amyloid accumulated in plaques was Congo red negative.     

Comparison of fertility on intrauterine insemination between cryopreserved ejaculated and cauda epididymal sperm in dogs

The fertility was compared between ejaculated and cauda epididymal sperm sensitized with prostatic fluid in dog after freeze-thawing using the fertility of ova from the contralateral ovary after injection (2 × 10(8) sperm) into dog uterus on the unilateral ovariectomized side, on the basis of the presence or absence of conception. No significant difference was observed in sperm quality after freeze-thawing between the two groups and conception rates were equivalent and low. Therefore, to achieve a high fertility by intrauterine insemination of canine frozen-thawed ejaculated and cauda epididymal sperm, intrauterine insemination on both sides is recommended, rather than insemination with a lot of sperm of the uterine horn on one side.