Topic:Atresia
Atresia in horses refers to the congenital absence or closure of a normal body opening or tubular structure. This condition can affect various parts of the equine anatomy, including the gastrointestinal tract, reproductive system, and respiratory pathways. Atresia can lead to clinical symptoms such as colic, difficulty in breathing, or reproductive challenges, depending on the location and severity of the obstruction. Diagnosis typically involves clinical examination, imaging techniques, and sometimes exploratory surgery. Treatment options may include surgical intervention to correct or bypass the obstruction. This page gathers peer-reviewed research studies and scholarly articles that explore the types, diagnosis, management, and outcomes of atresia in equine medicine.
Congenital heart defects in Arabian horses and the prospects of genetic testing: A review. Congenital heart defects (CHDs) can have profound and potentially life-threatening consequences on horses' health and performance capability. While CHDs are rare in the general horse population, the Arabian breed is disproportionately overrepresented and thus is widely suspected to be genetically predisposed. This review discusses the most common CHDs in Arabian horses, including ventricular septal defect (VSD), tetralogy of Fallot (TOF), patent duct arteriosus (PDA), tricuspid valve atresia (TVA) and atrial septal defect (ASD). This review also explores how future research into the genetic fa...
Postmortem magnetic resonance imaging findings of tricuspid atresia with ventricular and atrial septal defects and subvalvular pulmonic stenosis in a Japanese native Noma horse. The necropsy of a 2-day-old Noma horse that died of weakness showed an enlarged cardiac base and a narrow cardiac apex, suggesting cardiac malformation. The excised heart underwent imaging to investigate its luminal structure. On three-dimensional magnetic resonance imaging, the right atrium and right ventricle were discontinuous. The right atrium communicated with the left atrium and the left ventricle communicated with the right ventricle. The lumen narrowed near the pulmonary artery valve. Since the same findings were observed on gross examination, the foal was diagnosed with tricuspid atre...
Expression of apoptotic genes in immature and in vitro matured equine oocytes and cumulus cells. The gene expression of Bax, Bcl-2, survivin and p53, following in vitro maturation of equine oocytes, was compared in morphologically distinct oocytes and cumulus cells. Cumulus-oocyte complexes (COC) were harvested and divided into two groups: G1 - morphologically healthy cells; and G2 - less viable cells or cells with some degree of atresia. Total RNA was isolated from both immature and in vitro matured COC and real-time reverse transcription polymerase chain reaction (qRT-PCR) was used to quantify gene expression. Our results showed there was significantly higher expression of survivin (P &...
Characterization of matrix metalloproteinase-2 and matrix metalloproteinase-9 and their inhibitors in equine granulosa cells in vivo and in vitro. Matrix metalloproteinases (MMP) and tissue inhibitors of MMP (TIMP) regulate tissue remodeling events necessary for ovulation. Thus, changes in MMP and TIMP expression and protein enzyme activity were examined in vivo and in vitro during follicular development and atresia in the horse. Equine granulosa cells and follicular fluid from medium (15 to 29 mm) healthy and atretic follicles and from large (>30 mm) healthy and preovulatory follicles were collected by transvaginal aspiration. The cells were either snap-frozen (in vivo study) or cultured for 48 h (in vitro study) to determine gene ex...
Ovarian follicular growth and development in mammals. Evidence from several species indicates that the initial stages of follicular growth proceed very slowly. In contrast, the stages after antrum formation are much more rapid. Atresia seems to be most prevalent as follicles approach the size at which they could be recruited for potential ovulation. Although most follicles become atretic around that stage, a few are recruited into a cohort or wave of follicles that continue to grow beyond the stage at which atresia normally occurs. Next, a species-specific number of follicles is selected for dominance. In some species (e.g. rats, primates, pigs),...
Atresia coli in the foal: a review of six cases. Physical examination and exploratory celiotomy were performed on five neonatal foals presented with signs of acute colic. Atresia coli was confirmed in each foal during surgery. The most consistent finding on physical examination was the absence of meconium staining following repeated enemas. The large, transverse and/or small colon were involved in all foals. One eight month aborted foetus was submitted for necropsy and diagnosed as having atresia coli and congenital hydrocephalus. Atresia coli should be considered for neonatal foals with signs of acute colic.