Developmental aspects of early pregnancy in mares

In mares, the embryo mi grates to the uterus between days 5 and 6 postovulation beginning its mobility through all uterine segments, which is essential for the maternal recognition of pregnancy. During the mobility phase, the embryonic vesicle shows a linear growth rate until its fixation between days 15 and 17, when the orientation phenomenon occurs. From fixation to day 28 of pregnancy, the embryonic growth is less evident (plateau) by cross-section ultrasound examination. After this period the linear growth rate is reestablished until day 46. This plateau is attributed to the increased uterine tone that compresses the vesicle and to volume expansion, making it difficult to detect the conceptus growth only by the cross-section diameter. Around day 20, the embryo proper is visualized as an echogenic spot in the ventral aspect of the vesicle. Additionally, development of allantoic sac, embryonic heartbeat, yolk sac regression and posterior umbilical cord formation also can be visualized from days 20 to 40. An intimate interaction between uterus and conceptus is essential for the normal pregnancy development. Color- and spectral-Doppler ultrasonography can be useful for the evaluation of this interface. A gradual increase on uterine vascularity during the early pregnancy and transient changes in endometrial vascularity accompanying the vesicle location during the mobility phase have been described. Around day 38 of gestation, the formation of the endometrial cups begins and, consequently, the synthesis of the equine chorionic gonadotropin (eCG) induces the formation and development of supplementary corpora lutea, which are important to secrete progesterone and to maintain pregnancy until around day 120.

Developmental aspects of early pregnancy in mares

In mares, the embryo mi grates to the uterus between days 5 and 6 postovulation beginning its mobility through all uterine segments, which is essential for the maternal recognition of pregnancy. During the mobility phase, the embryonic vesicle shows a linear growth rate until its fixation between days 15 and 17, when the orientation phenomenon occurs. From fixation to day 28 of pregnancy, the embryonic growth is less evident (plateau) by cross-section ultrasound examination. After this period the linear growth rate is reestablished until day 46. This plateau is attributed to the increased uterine tone that compresses the vesicle and to volume expansion, making it difficult to detect the conceptus growth only by the cross-section diameter. Around day 20, the embryo proper is visualized as an echogenic spot in the ventral aspect of the vesicle. Additionally, development of allantoic sac, embryonic heartbeat, yolk sac regression and posterior umbilical cord formation also can be visualized from days 20 to 40. An intimate interaction between uterus and conceptus is essential for the normal pregnancy development. Color- and spectral-Doppler ultrasonography can be useful for the evaluation of this interface. A gradual increase on uterine vascularity during the early pregnancy and transient changes in endometrial vascularity accompanying the vesicle location during the mobility phase have been described. Around day 38 of gestation, the formation of the endometrial cups begins and, consequently, the synthesis of the equine chorionic gonadotropin (eCG) induces the formation and development of supplementary corpora lutea, which are important to secrete progesterone and to maintain pregnancy until around day 120.(AU)

Carcinoma mamário em égua: achados clínicos e histopatológicos / Mammary carcinoma in a mare: clinical and histopathological findings

Uma égua da raça Quarto-de-Milha, doadora de embriões, de vinte e três anos de idade foi atendida no Departamento de Reprodução Animal e Radiologia Veterinária da FMVZ - UNESP - Botucatu, apresentando uma massa ulcerada, de consistência firme, drenando secreção serosanguinolenta, medindo 15cm x 16cm x 14,8cm na mama direita. O exame citológico foi inconclusivo devido à baixa celularidade e predomínio de células inflamatórias. Foi realizada mastectomia unilateral e exame histopatológico que revelaram um carcinoma mamário túbulo-papilífero, com extensivo acometimento intralobular e intraductal, estroma abundante e infiltrado inflamatório polimorfonuclear acentuado e difuso. Este trabalho tem como objetivo relatar os achados clínico e histopatológicos de um caso de carcinoma mamário túbulo-papilífero em uma égua, confirmando a importância do exame citológico e histopatológico no diagnóstico diferencial de processos inflamatórios e neoplásicos.

A twenty three years old quarter horse mare, embryo donor, was attended at the Veterinary Radiology and Animal Reproduction Department - FMVZ - UNESP - Botucatu, showing an ulcerated, firm consistency mass, draining a serosanguineous secretion, measuring 15cm X 16cm X 14,8cm in the right udder. The cytological exam was inconclusive due to a low celularity and prevalence of inflammatory cells. An unilateral mastectomy and histopathological exam were performed, which revealed a tubulo-papillary mammary carcinoma, with extensive intralobular and intraductal involvement, with profuse stroma and marked and diffuse polymorphonuclear inflammatory infiltrate. The aim of this work is to describe the clinical and histopathological findings of a tubulo-papillary mammary carcinoma in a mare and affirm the importance of the histopathological and cytological exams on the differential diagnosis of neoplasms and inflammatory processes.