Investigation of efficacy of two different chemotherapy protocols used in neoadjuvant chemotherapy in clinical stages II-IV canine malignant mammary tumours.

The first aim of this study is to demonstrate the clinical efficacy and reliability of two different neoadjuvant chemotherapy (NAC) protocols consisting of doxorubicin/cyclophosphamide (AC) and paclitaxel in dogs with clinical stages II-IV canine malignant mammary tumours (CMTs). Secondly, to determine the Luminal A, Luminal B, HER2-positive and triple-negative molecular subtypes and their value in predicting clinical response to NAC in biopsy samples, and thirdly, to reveal the changes in Ki-67, human epidermal growth factor receptor type 2 (HER2), oestrogen receptor (ER), and progesterone receptor (PgR) expression levels induced by NAC. Thirty dogs with clinical stages II-IV CMTs (T1-3N0-1M0) according to the modified TNM system were included in the study. Dogs in group-1 (n = 15) AC combination and dogs in group-2 (n = 15) were administered paclitaxel. Partial response (PR) was the most common clinical response in both treatment groups (66.66% and 86.66%, respectively). There was no difference between the groups regarding clinical response parameters (p = .001). The rate of treatment responders was higher than the rate of non-responders in both groups (p < .001). The adverse effects observed in both groups were mostly limited to grades 1 and 2 and all were easy to manage. The most frequently detected molecular subtype was Luminal A (59.25%). Complete response (CR) was achieved in 33.33% of dogs with triple-negative CMT in the AC group and 14.29% of the Luminal A subtype in the paclitaxel group. Alterations in Ki-67, HER2, ER, and PgR expressions after chemotherapy were not statistically significant (p > .05). As a result, we have shown that these neoadjuvant chemotherapy protocols are effective and safe alternative treatment options for CMTs.

Evaluation of serum anti-Müllerian hormone concentrations following treatment with vitamin D in Holstein Friesian heifers.

Anti-Müllerian hormone (AMH) levels in the blood of dairy cattle are associated with the count of antral follicles (AFC), ovarian function. Numerous studies, particularly in human medicine, have shown that vitamin D3 (Vit D3) has a positive effect on AMH levels. To our knowledge, the effects of Vit D3 on serum AMH levels in heifers have not been investigated. The goal of the current study was to evaluate the concentrations of serum AMH in dairy heifers following Vit D3 treatment. The study included 20 healthy non-pregnant Holstein Friesian heifers. These animals came to estrus at least once. All heifers received a single intramuscular dosage of 5 million IU Vit D3 (Cholecalciferol). Blood samples were collected from the coccygeal veins of all animals before and after Vit D3 injection (days 7, 14, and 28) for the measurement of AMH and 25(OH)D concentrations. In our analysis, we observed that after exogenous Vit D3 administration, circular 25(OH)D increased constantly (up to day 28 after Vit D3 injection) in all animals. On day 28, AMH concentrations saw a 10% increase in comparison with those measured the day before the Vit D3 injection. However, a comparison of AMH concentrations measured across days did not reveal statistically significant differences between Day 0, 7, 14, and 28 levels (p = .10). Furthermore, no statistical correlation was observed between the pairs (age-AMH) and (weight-AMH). Considering all times, no correlation was found between 25(OH)D and blood AMH levels. These findings demonstrated that exogenous Vit D3 did not affect serum AMH in Holstein Friesian heifers.