Search

The canine placenta is an underexamined organ. Placental abnormalities can affect foetus development and may be responsible for a low weight of the infant at birth; however, knowledge on their clinical significance in the canine species is limited. We aimed to describe macroscopic and microscopic findings in the canine placenta and amnion at term in clinically uncomplicated pregnancies and to evaluate their relationship with birth weight of healthy puppies. During natural delivery or C-section, the birth weight of 82 puppies was recorded, 72 placentas and 66 amnions were recovered. The foetal and maternal surfaces of the placental girdle, marginal haematoma and amnion were evaluated. Each gross finding was recorded, morphometrically assessed and sampled for histological diagnosis. Furthermore, specimens of placenta and amnion were collected from representative areas and microscopic deviations from normal structure were evaluated in haematoxylin and eosin sections. Gross examination revealed 'abnormalities' in the 75.4% of the collected placentas. Necrosis was the gross change most commonly observed in the placental girdle (72.5%). Congestion (17.4%) and clotted blood/fibrinoid material (2.9%) were also observed. No gross changes of either the marginal haematoma or the amnion were recorded. Histologically, placental girdle showed necrosis (62.3%), mineralization (52.2%), congestion (36.2%) and neutrophilic infiltration (27.5%). Marginal haematoma exhibited mineralization (11.6%) and neutrophils (29%), while necrotic foci were rarely observed (4.3%). In the amnion, the most frequent alteration observed was hypertrophy of the epithelium (35.9%) followed by oedema (31.2%), mineralized foci (28.1%), fibrosis (23.4%), congestion (15.6%) and more rarely neutrophils (12.5%). Puppies' birth weight was not statistically affected by either gross or histological abnormalities. Our study revealed that macroscopic and microscopic 'abnormalities' of the placenta and amnion may be common in uncomplicated pregnancies at term; however, no implications on puppies' birth weight were observed. Deviations from 'normal' morphology of canine foetal adnexa warrant further investigation to assess their clinical implications if present., (© 2021 Wiley-VCH GmbH.)

There are age-related changes in testicular anatomy and physiology whereby there are modifications of sperm production and reproductive hormone functions. Effects of age on testicular microanatomy are well documented in humans, while there is limited understanding of these changes in dogs. The aim of this study was to evaluate age-related changes of seminiferous tubule morphology, interstitial fibrosis and spermatogenesis in dogs. Dogs (n = 32) were divided into four age groups: peripubertal (n = eight), relatively younger (n = seven), reproductively mature (n = seven) and relatively older (n = ten). Picrosirius Red stained sections were used for morphometrical analysis of testicular tissues, while the characteristics of seminiferous epithelium were assessed using a modified Johnsen scoring system for haematoxylin and eosin stained sections. Seminiferous epithelium and seminiferous tubule area increased from peripuberty to reproductive maturity, indicating there were changes during sexual maturation and subsequently there were decreases with further aging. There was a similar age-related trend for changes in seminiferous epithelium height with values being greatest in reproductively mature dogs; while there were no age-related differences in tubular diameter. Collagen content in the testicular interstitium gradually decreased from peripuberty to the age when dogs were reproductively mature and there were subsequent increases in relatively older dogs, thus, there was an association between the extent of testicular fibrosis and senescence. There was a decrease in spermatogenetic functions from relatively younger to older ages. Further investigations are warranted to establish mechanisms responsible for age-related changes of testicular morphology and related clinical implications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2020 Elsevier B.V. All rights reserved.)

Puppy neonatal mortality may be related to low birth weight, which has been shown in humans to be linked to placental factors. The relation between the newborn puppy and the placental characteristics has been poorly investigated in dogs. Twenty bitches, 9 toy-sized (i.e. < 5 Kg) and 11 small-sized (i.e. 5 to 10 Kg), were included in this study. During natural delivery or c-section, puppies were identified and their order of birth, sex and weight were recorded. Puppy weights were registered at birth and daily until Day 6. Placentas were weighed after removal of extraplacental adnexa, after which a photo was taken and morphometrically assessed. The Total Placental Area (TPA) and the Transfer Zone Area (TZA) were calculated and their surface expressed in mm 2 . Immunohistochemistry with monoclonal mouse anti CD31 antibody was used to identify fetal and maternal vessels in the placental labyrinth zone. A vascularization index (VI) was determined for each placenta and the Total Vascular Area (TVA) was estimated. Puppies' birth weight correlated positively with placental weight (P < 0.001, r = 0.689). A positive correlation was found between the puppies' birth weight and TPA (P < 0.001, r = 0.786), TZA (P < 0.001, r = 0.772), and TVA (P < 0.001, r = 0.482). A positive correlation was also found between placental weight and TPA (P < 0.001, r = 0.661), TZA (P < 0.001, r = 0.583), and TVA (P < 0.001, r = 0.333). In the small-sized breeds, the placentas of low-weight puppies were lighter and had a smaller TZA and TVA (P < 0.05). The VI was higher in the placentas of the toy-sized compared to small-sized bitches (P < 0.01). No effect of parity, litter size, or sex of the puppy was observed on birth weight or growth rates on Day 6. The growth pattern of low-weight puppies did not differ from that of the other puppies during the first 6 days of life. As in humans, placental weight, the extension of the transfer zone and placental total vascular area correlates closely with the puppies' birth weight in normal pregnancies. Our data could represent reference values for placental weight, TZA, TVA and VI in toy and small-sized dog breeds., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: It is commonly accepted that canine dystrophic mineralization of the hair follicle glassy membrane can be seen in hyperadrenocorticism and as a senile change in poodles. Pathology textbooks define this change as deposition of calcium salts in the form of basophilic, amorphous, granular material along collagen fibrils., Hypothesis/objectives: The aim was to evaluate whether the incidence of the lesion is specific to poodles and if it is always associated with calcium deposition., Animals: One hundred and forty-seven dogs divided into three groups: (i) 91 normal poodles; (ii) 40 dogs of other breeds; and (iii) 16 dogs with clinical/histopathological diagnosis of hyperadrenocorticism., Methods and Materials: Retrospective study; with haematoxylin and eosin, and von Kossa staining., Results: Our findings demonstrate that perifollicular changes of the hair follicle glassy membrane of poodles are not always associated with calcium deposition., Conclusions and Clinical Importance: A specific staining is needed to identify true calcium deposition when performing histological examination of the skin of poodles., (© 2018 ESVD and ACVD.)

Background: Increased cancer rates have been documented in people residing in areas around Naples characterized by illegal dumping and incineration of waste. Hypothesis: Risk of cancer in dogs and cats is associated with waste management. Animals: Four hundred and fifty-three dogs and cats with cancer and 1,554 cancer-free animals. Methods: Hospital-based case-control study in Naples (low danger) and nearby cities having a history of illegal waste dumping (high danger). Odds ratio (OR) between high- and low-danger areas was calculated for all tumors and various malignancies in dogs and cats. Results: An increased risk for cancer development was identified in dogs but not in cats residing in high-danger areas (OR: 1.55; 95% confidence interval: 1.18–2.03; P < .01). A 2.39-fold increased risk of lymphoma ( P < .01) accounted for the greater tumor frequency in dogs residing in high-danger areas. The risk of mast cell tumor and mammary cancer did not differ in dogs residing in high- or low-danger areas. Conclusions and Clinical Importance: Waste emission from illegal dumping sites increases cancer risk in dogs residing in high-danger areas. An increased prevalence of lymphoma has been previously recognized in humans living close to illegal waste dumps. Thus, epidemiological studies of spontaneous tumors in dogs might suggest a role for environmental factors in canine and human carcinogenesis and can predict health hazards for humans. [ABSTRACT FROM AUTHOR]

Canine cutaneous mast cell tumours (MCTs) have a variable biologic behaviour, and accurate staging is necessary to dictate therapy and predict outcome. Regional lymph node (RLN) involvement is a relevant prognostic factor. While obvious lymph node (LN) metastases are relatively easy to be diagnosed, micrometastatic disease recognition is challenging. The main aim of the study was to evaluate the number of mast cells (MCs) in the LNs of clinically healthy dogs ( n = 4, group 1), dogs with inflammatory diseases ( n = 31, group 2) and dogs with cutaneous MCT ( n = 27, group 3), including animals with no RLN metastases (subgroup 3.1), those with occasional MCs in RLNs (3.2) and those with obvious RLN metastasis (3.3). MCs also were morphometrically evaluated for the following nuclear parameters: mean nuclear area (MNA), mean nuclear perimeter (MNP), largest to smallest diameter length (LS ratio), mean nuclear form factor and coefficient of variation of nuclear area. The average percentages of MCs were 0.0 and 0.01 in groups 1 and 2, respectively, and 0.07, 2.4 and 47.1 in subgroup 3.1, 3.2 and 3.3. MNA and MNP were significantly higher in subgroup 3.3 than in group 2 ( P < 0.05). MNA and MNP in subgroup 3.2 suggested the presence of neoplastic MCs; this prediction of micrometastatic load correlated with outcome. Analysis of preliminary results shows that nuclear morphometry is useful to detect micrometastatic disease in RLN of dogs bearing cutaneous MCTs. [ABSTRACT FROM AUTHOR]

Canine mammary tumours are generally treated with surgery alone, despite the fact that 50% of them are malignant and many will eventually lead to recurrence or metastases. A prospective clinical trial in which dogs with aggressive mammary carcinoma of clinical stages IV and V were treated with surgical excision ( n = 9) or with surgery and adjuvant weekly gemcitabine ( n = 10) for at least four cycles was conducted. Gemcitabine was given as an intravenous infusion at the dose of 800 mg m−2. Aim of the study was to explore potential beneficial effects of gemcitabine on time to local recurrence (TTR), time to distant metastases (TTM) and overall survival (OS) in canine patients with operated mammary tumours bearing high risk for locoregional failure and distant metastases. Also, factors associated with OS, including neutering status, body weight, age, clinical stage at presentation, tumour size, histological grade and, in dogs receiving chemotherapy, the number of gemcitabine treatments, were investigated. Finally, acute toxicities related to chemotherapy and quality of life were assessed in dogs receiving gemcitabine. Dogs treated with surgery alone or surgery followed by gemcitabine had no difference in TTR, TTM or OS ( P > 0.05). In the group of dogs receiving adjuvant chemotherapy, the number of gemcitabine treatments was positively correlated with OS ( P = 0.017). Gemcitabine treatment was well tolerated, with no dogs experiencing clinically relevant haematological or gastrointestinal toxicity. Despite being safe at the present dose, gemcitabine chemotherapy as an adjunct treatment to surgical excision may not be recommended in dogs with aggressive mammary carcinoma. [ABSTRACT FROM AUTHOR]

Objectives To evaluate the efficacy of a hydrocolloid dressing for the treatment of surgical wounds in dogs. Methods Six healthy young female dogs of medium size and different breed underwent ovariohysterectomy. Histological evaluation was performed on biopsies taken from the edges of the wounds at day 7. The dressing was applied on one half of the wound according to manufacturer's instructions; the second half served as control. Biopsy specimens were fixed in a 10% formalin buffered solution pH 7.4, paraffin embedded and stained with haematoxylin and eosin. For clinical assessment, the presence and quality of exudate, erythema of the surrounding area, swelling and correct apposition of the wound margins were evaluated. Results The hydrocolloid dressing was easy to use. The clinical quality of the treated skin wounds was superior to the non-treated ones. Comparison of histological features between treated and untreated wounds showed a more regular organisation of the granulation tissue in the treated wounds, with fibroblasts being aligned parallel to the overlying epidermis. The number of inflammatory cells and the extension of granulation tissue were less prominent and less widespread in treated compared to untreated wounds. Conclusion The dressing performed very well in terms of adhesiveness and flexibility. It was useful in the management of surgical wounds to avoid contamination and ameliorate the epithelialisation rate and granulation tissue morphology of the surgical scar. [ABSTRACT FROM AUTHOR]

Mast cells (MC) are pivotal in wound healing. Adelmidrol, a synthetic autacoid, can down-regulate MC degranulation and potentially accelerate healing and improve cosmetic outcome. This study evaluated an Adelmidrol gel on MC in experimental wounds. Two rows of six 5-mm wounds were created in 10 beagles and allowed to heal; one row was treated daily with therapeutic gel and the other with vehicle only. Treated and control 8-mm samples of wounds were taken after 1, 2, 4, 8 and 14 days, fixed in formalin and paraffin embedded. Four-micrometer sections were stained with toluidine blue for MC counts and densitometry. Counts (MC/mm2) were obtained from areas lateral to and within the ulcer/granulation tissue, and in deep dermis/panniculus. A decreasing trend in MC counts occurred throughout days 1 (3.8 ± 11.3), 2 (4.3 ± 14.9) and 4 (4.3 ± 9.9) compared to day 0 (5.0 ± 10.6), followed by an increase at day 8 (6.0 ± 12.3) and a significant increase at day 14 (10.0 ± 18) compared to days 1, 2 and 4 in granulation tissue and perifollicular areas ( P < 0.05) and deep dermis/panniculus ( P < 0.01). No difference in MC counts was detected between treated and control wounds. Preliminary data from two dogs showed granulation density was higher in treated wounds from day 2 (119.1 ± 27.4 vs . 69.4 ± 14.2) until day 14 (92.4 ± 22.1 vs. 67.9 ± 12.9). In conclusion, MC populations seem to change during wound healing. The autacoid gel did not alter MC numbers, but decreased degranulation. Funding: Royal Veterinary College, Innovet. [ABSTRACT FROM AUTHOR]