Search

Understanding the normal physiology of the canine mammary gland (CMG) is crucial, as it provides a foundational reference for understanding canine mammary neoplasms. The relation between the Proliferation Index (PI) indicated by Ki-67 expression, along with the Apoptotic Index (AI) determined through Caspase-3 expression during the oestrous cycle, is inadequately documented in existing literature. This study seeks to offer insights into the interplay between PI and AI in the CMG across oestrous cycle phases. An extensive investigation was conducted on a diverse case series of bitches (n = 18). Oestrous cycle stages were determined through vaginal cytology, histological examination of the reproductive tract and serum progesterone and oestradiol concentrations. The entire mammary chain was histologically examined, and proliferation and apoptosis were assessed via double immunohistochemistry employing anti-Ki-67 and Caspase-3 antibodies. PI and AI were evaluated through a systematic random sampling approach, counting a minimum of 200 cells for each cell type. There was a significantly higher PI during early dioestrus in all mammary gland components, with a greater proportion of positive cells observed in epithelial cells compared to stromal cells. The highest PI was detected in epithelial cells within the end buds. Significant differences were found in Ki-67 labelling across the cranial mammary glands. A positive and strong correlation was noted between progesterone concentration and PI in epithelial cells. The AI remained consistently low throughout the oestrous cycle, with few differences observed across histological components. Caspase-3 labelling displayed the highest positivity in caudal mammary pairs. A negative and moderate correlation was identified between progesterone concentration and AI in interlobular mesenchymal cells. This study highlights the influence of endocrine regulation on cell proliferation indices in mammary tissue, emphasizing the need to consider these hormonal variations in toxicopathological studies involving canine mammary gland., (© 2024 Wiley‐VCH GmbH. Published by John Wiley & Sons Ltd.)

Prostatomegaly is a common finding in older non-neutered dogs. This study compared the serum testosterone, sperm quality and characteristics of the prostatic fraction between healthy dogs and dogs with prostatomegaly. Blood samples of ten dogs (five dogs from each group) were taken for serum testosterone measurement. Sperm motility, vigour, concentration, viability, membrane functionality and morphology were analysed in sperm-rich fraction. Osmolality, pH, cell types, and albumin, haemoglobin, acid phosphatase, alkaline phosphatase, glucose, triglycerides, cholesterol, calcium, phosphorus, magnesium and chloride were analysed in prostatic fraction. Dogs with prostatomegaly have the lowest sperm motility, vigour, concentration and functional membrane. Dogs with prostatomegaly have the highest glucose, triglycerides and cholesterol. Glucose was the only constituent positively correlated with serum testosterone and prostate volume. It can be concluded that dogs with prostatomegaly have poorer sperm quality, and glucose, triglycerides and cholesterol in prostatic fraction can be used as prostatomegaly biomarkers., (© 2017 Blackwell Verlag GmbH.)

The cryopreservation of testicular tissue is presented as the only alternative for the preservation of genetic material from prepubertal animals. However, this biotechnology is still being tested. The objective of this study was to evaluate the effect of different associations of cryoprotectants and the potential of cell proliferation after vitrification of testicular tissue of prepubertal cats. Five testicular pairs from five prepubertal cats were used, and each pair was divided into four fragments. Of these, one fragment composed of the control group (CG) and the rest were distributed in experimental groups according to the associations of cryoprotectants to be tested (dimethyl sulphoxide (DMSO)/glycerol (GLY); ethylene glycol (EG)/GLY) or DMSO/EG) in a final cryoprotectant concentration of 5.6 m. The fragments were submitted to vitrification, and after one week, fragments were heated and processed for histomorphological evaluation and quantification of nucleolar organizer regions (NORs). DMSO/GLY did not differ from CG and was superior to the other vitrified groups, as to cell separation and degree of shrinkage of the basal membrane. Concerning cell differentiation, visibility of the nucleus and nuclear condensation, all the vitrified groups were inferior to CG; however, DMSO/EG was inferior to DMSO/GLY and EG/GLY, which did not differ among themselves. CG was superior to all groups in quantification of NORs. DMSO/EG was inferior to all others, and there was no difference between DMSO/GLY and EG/GLY. The association DMSO/GLY presented the best preservation of tissue integrity and potential of cell proliferation after vitrification of the testicular tissue of prepubertal cats., (© 2016 Blackwell Verlag GmbH.)

The reproductive potential of male animals is commonly evaluated using a breeding soundness examination incorporating B-mode ultrasound examination of the testes and recently Doppler ultrasound examination of the testicular arteries. These techniques may detect testicular normality or pathology, and while some measured parameters are associated with semen quality at the time of ultrasound examination, few studies have investigated the relationship with future semen quality. We hypothesized that B-mode and Doppler ultrasound measurements would correlate with future semen quality. Within two studies, we investigated the relationship between ultrasound measured testicular volume, testicular echogenicity, testicular homogeneity, subjective assessment of the testicular parenchyma, testicular artery resistance index, and pulsatility index with subsequent semen quality. Fifty-five normal fertile dogs of which 29 had stable semen quality and 26 had a subsequent decline in semen quality were examined during a 6-month period commencing 62 days after the ultrasound examination. Statistical analysis showed that no ultrasound parameters were predictive of future total sperm output or percentage live normal sperm. However, mean testicular echogenicity was positively related to future sperm motility (t = 2.202, p = .039). We conclude that quantitative ultrasound assessment of the appearance of the testicular parenchyma has potential for the evaluation of future semen quality in dogs., (© 2016 Blackwell Verlag GmbH.)