Factors affecting recipients' pregnancy, pregnancy loss, and foaling rates in a commercial equine embryo transfer program

During 11 breeding seasons, 351 7- to 10-day-old horse embryos were nonsurgically transferred into recipients that ovulated between 3 and 10 days earlier. Pregnancy rates at 14 and 40 days and foaling rates were 77.8% (273/351), 69.2% (243/351), and 64.4% (226/351), respectively. Pregnancy loss between 14 and 40 days was 11% and between 40 days and delivery was 7%. The transfer of quality grade 3 to 4 embryos resulted in a significantly lower pregnancy rate at 14 days compared with the transfer of grade 1 to 2 embryos (46.2% vs. 79%; P < .05). Eight-day-old embryos resulted in significantly lower pregnancy losses than day 9 or 10 embryos, as occurred for embryos between 400 and 1200 μm compared with embryos <400 μm. Embryos recovered from mares >20 years resulted in a significantly higher pregnancy loss rate than those recovered from younger mares. The same happened for embryos coming from mares affected by reproductive pathologies compared with healthy mares performing sport activity. None of the evaluated parameters influenced recipients' foaling rate significantly

Co-localization of PTEN and E-cadherin in canine mammary hyperplasias and benign and malignant mammary tumours

Fifty-four canine mammary lesions (15 hyperplasias, 7 adenomas and 32 carcinomas) were submitted to immunohistochemical analysis for the evaluation of PTEN and E-cadherin co-expression. Subjects bearing mammary carcinomas were also submitted to a 2-year follow-up study to compare immunohistochemical results with overall survival All the hyperplastic samples stained positive for both markers, 100% of adenomas were positive for PTEN and 86% for E-cadherin, and 69% and 34% of carcinomas were positive for PTEN and E-cadherin, respectively. Statistical analysis showed a positive correlation between these two proteins both considering all (p <0.01) or malignant tumours (p <0.05). The female dogs bearing tumours positively-stained for both markers had a longer overall survival (p <0.05) and absence of lymphatics invasion (p <0.05). Simultaneous double immunofluorescence confirmed the co-localization of the two proteins in neoplastic cells. Results reported in this study confirm the tumor suppressor effect of these two molecules

Retrospective study of factors affecting multiple ovulations, embryo recovery, quality, and diameter in a commercial equine embryo transfer program

In this study, 198 donor mares of different breeds, ages, and reproductive category were inseminated with fresh, cooled and frozen or frozen and cooled semen at the embryo transfer station or in private artificial insemination centers during 10 breeding seasons. The results of this activity were retrospectively analyzed by Pearson Chi-square test and logistic regression to evaluate factors affecting multiple ovulations, embryo recovery, embryo quality, and embryo diameter. Out of the 661 cycles, 937 ovulations were recorded (mean ovulations/cycle: 1.42 ± 0.58). Ovulation rate and incidence of multiple ovulations were significantly affected by age, breed, and reproductive category. Uterine flushings for embryo recovery were performed between 7 and 10 days after ovulation and resulted in the recovery of 338 embryos (51.1% embryos/cycle and 36.1% embryos/ovulation, respectively). At least one embryo was recovered in 298 flushings (45.1%). The factors affecting embryo recovery were age, breed, reproductive category, type of semen, number of ovulations, and location of artificial insemination. Flushing protocol and day of flushing had no effect on embryo recovery. Age, type of semen, number of ovulations, and day of flushing had a significant influence on embryo diameter (N = 215). None of the factors included in the model had an effect on embryo quality distribution

Development of a short-term canine full-thickness skin organ culture method under serum-free conditions

Full-thickness canine skin organ culture models could provide an entirely new opportunity for studying wound healing, keratinization disorders and allergic skin diseases, all of which have high prevalence and severe impact on canine quality of life. Here we present a canine organ culture method for the short-term maintenance of full-thickness, adult, canine skin in serum-free medium and investigate the possibility to induce mast cell degranulation ex vivo. General morphological features were maintained up to day 7. Epidermal thickness started to decrease from day 4 of culture. No changes were observed in epidermal pigmentation. Keratinocyte proliferation started to significantly decrease at day 7. Immunostaining for cytokeratin 10, cytokeratin 14 and loricrin was evident from day 1 to day 7. Compound 48/80 induced mast cell degranulation. This was the first attempt to establish a dog skin organ culture and document good preservation of most cutaneous structures till day 7. This method may help in dissecting canine skin biology in physiological and pathological conditions and to study drug mechanism of action in a biologically relevant environment

Corpus luteum vascularization and progesterone production in Autumn and Winter cycles of the mare: relationship between ultrasonographic characteristics of corpora lutea and plasma progesterone concentration in the last cycles before anestrus

In 20 estrus cycles of 15 mares, Color Doppler ultrasound of corpora lutea and plasma progesterone concentration ([P4]) were analyzed on days 6, 10, 14, 16 and 18 after ovulation. [P4] was positively correlated with corpora lutea cross sectional area (CSA), vascularized area (VA) and index of vascularization (IV=VA/CSA) (P 1 ng/ml. Mares with CSA <3473 pixels, VA<25.5 pixels and a IV <7.6% were prone to express [P4] <1 ng/ml 25.4, 7.9 and 7.6 times more than mares with higher values, respectively. CLs analyzed parameters differed significantly between last cycles of the breeding season and previous cycles until day 14 after ovulation (P<0.05). No significant differences were found in [P4] between last cycles and previous ones

An Immunohistochemical Study of the PTEN/AKT Pathway Involvement in Canine and Feline Mammary Tumors

Phosphatase and tensin homolog deleted on chromosome10 (PTEN), phospho-v-Akt murine thymoma viral oncogene homolog (AKT), and the Rapamycin-Insensitive Companion of mTOR (Rictor) expression was investigated by immunohistochemistry in 10 canine mammary adenomas (CMAs), 40 canine mammary carcinomas (CMCs), and 30 feline mammary carcinomas (FMCs). All the CMAs, 25 of 40 CMCs (63%) and 7 of 30 FMCs (23%), were PTEN-positive. In dogs, no CMAs and 15 of 25 CMCs (37%) expressed phospho-AKT (p-AKT), while 24 of 30 FMCs (82%) were p-AKT-positive. One of 10 CMAs (10%), 24 of 40 CMCs (60%) and 20 of 30 FMCs (67%) were Rictor-positive. In the dog, PTEN expression correlated with less aggressive tumors, absence of lymphatic invasion, and longer survival. P-AKT expression correlated with more aggressive subtype, lymphatic invasion, and poorer survival and Rictor expression with lymphatic invasion. In cats, PTEN correlated with less aggressive carcinomas, absence of lymphatic invasion, and better survival. P-AKT and Rictor expression correlated with poorer survival. PTEN expression was inversely correlated with p-AKT and Rictor in both species, while p-AKT positively correlated with Rictor expression. A strong PTEN/AKT pathway involvement in behavior worsening of CMT and FMTs is demonstrated, providing a rationale for further studies of this pathway in veterinary oncology

Monitoraggio ecografico dell’ovulazione nella cagna: risultati preliminari

RIASSUNTO Gli autori descrivono la loro esperienza inerente il monitoraggio ecografico dell’ovulazione in sei cagne. I reperti ecografici sono stati interpretati correlandoli con la colpocitologia e il dosaggio del progesterone ematico durante le fasi di proestro ed estro. Durante la fase preovulatoria l’ovaia appare ovoidale e contiene strutture rotondeggianti anecogene (follicoli), nel periodo postovulatorio diventa bozzellata per la presenza di strutture ipoecogene (corpi lutei) che sporgono dalla sua superficie. In nessun caso è stato possibile osservare il collasso dei follicoli durante l’ovulazione. Poiché è stata osservata una correlazione significativa tra l’aumento preovulatorio del progesterone plasmatico e l’ispessimento della parete follicolare (luteinizzazione preovulatoria), gli autori ritengono che l’ecografia possa costituire un valido ausilio nella determinazione del momento dell’ovulazione nella cagna. SUMMARY The authors describe their experience about ultrasonographic monitoring of ovulation in six bitches. Ultrasonographic findings were correlated with colpocitology and progesterone plasma concentration during proestrus and estrus. During the preovulatory period ovary is ovoidal-shaped and contains anechoic structures (follicles); after ovulation, the presence of hypoechogenic structures (corpora lutea) protruding above the surface of the ovary makes the ovarian profile irregular. Follicular collapse was not detected during ovulation. Because a significant correlation between preovulatory elevation of plasma progesterone levels and follicular wall thickening (preovulatory luteinization) was observed, the authors assume that ultrasonography might be a useful tool in timing ovulation in bitches

Su di un caso di schwannoma di grandi dimensioni nel cane

RIASSUNTO Gli schwannomi sono neoplasie benigne o maligne delle guaine nervose: la loro sintomatologia è correlata alle dimensioni e quindi all’effetto compressivo esercitato dal tumore sul nervo stesso. In genere originano da un plesso nervoso o da un ganglio, diffondendosi lungo il decorso del nervo. Colpiscono prevalentemente le radici dei nervi spinali nel tratto cervicale inferiore e toracico superiore, oltre ai nervi che originano dal plesso brachiale. Più raramente può essere interessata la porzione distale dei nervi periferici. La neoplasia si osserva con maggiore frequenza in soggetti in età avanzata. Lo scopo del presente lavoro è descrivere un caso di schwannoma di elevate dimensioni localizzato sulla regione dell’anca destra di un cane che presentava come unico disturbo un’alterata deambulazione. Una volta eseguiti gli esami diagnostici necessari si è proceduto all’exeresi della neoformazione e, sulla base del referto istopatologico, si è potuta formulare la diagnosi di “Schwannoma maligno mixoide”. I controlli post-operatori, condotti fino a 9 mesi dopo l’intervento, non hanno rilevato recidive della lesione. SUMMARY Schwannomas are classified as benign or malignant tumors of peripheral nerve’s sheath, with symtomatology depending by the compressive effect of tumor size. They usually arise from nervous plexus or from a ganglio, developing along the course of a nerve. These tumors often affect the spinal nerve’s roots in the lower cervical and superior thoracic length and the nerves originating from the brachial plexus, while rarely affect the distal portion of peripheral and/or cranial nerves. Dogs bearing nerve sheath tumors are middle aged or older. The purpose of the present study was to describe an anomalous case of large schwannoma located on the right haunch’s region of a three years old maremman shepherd dog, examinated in Clinical Veterinary Department on May 2004. The only clynical syntom detectable was a distorted deambulation, ascribable to the mass’s weight. After a careful clinical check-up and routine diagnostics procedures, an echographyc examination of the mass showed the presence of cystic formation with a corpuscular content, mixed to solid areas. The tumor was surgically removed and submitted to a histologic exam. It was diagnosed as a “malignant myxoid schwannoma”. A 9-month clinical follow-up demonstrated the absence of tumour recurrence