Egypt is anticipated to be potentially influenced by the global climate warming. Therefore, the current study aimed to evaluate the influence of age on the fertility potential of Arabian stallions during summer breeding months. Arabian horses grouped according to their age into three groups, each involved six stallions: young (5-6 years), middle (11-12 years) and old (15-20 years) age gro...

REASONS FOR PERFORMING STUDY The response to the first outbreak of contagious equine metritis in South Africa included pioneering a web-based platform to coordinate key aspects of a national, real-time polymerase chain reaction (qPCR)-based stallion screening programme to determine the distribution and prevalence of Taylorella equigenitalis in stallions and exposed mares. OBJECTIVES To define...

BACKGROUND We aimed to determine whether children conceived with ovarian stimulation alone (OS(A)) would differ phenotypically and biochemically from naturally conceived children of fertile and subfertile parents. METHODS Healthy pre-pubertal children aged 3-10 years, born at term, after singleton pregnancies were recruited in Auckland (New Zealand) and were allocated into three groups: (i) c...

Visual motility analysis is the basis for routine quality evaluation of stallion semen, although its prognostic value for fertilizing ability is considered low. The present study evaluated the ability of a novel computer-assisted motility analyzer (QualiSpermTM) to determine the motility and velocity of ejaculated, extended stallion spermatozoa (collected from 10 stallions, 3 ejaculates/stallio...

The objectives of this study were to estimate direct heritability of 30 conformation and performance traits evaluated during 100-day stationary performance test and to predict the genetic effects in Polish Warmblood stallions. Inbreeding coefficients were estimated as well. Moreover, phenotypic and genetic trends were derived. The data were extracted from the database of the Polish Horse Breedi...

A consistently high level of stallion fertility plays an economically important role in modern horse breeding. We performed a genome-wide association study for estimated breeding values of the paternal component of the pregnancy rate per estrus cycle (EBV-PAT) in Hanoverian stallions. A total of 228 Hanoverian stallions were genotyped using the Equine SNP50 Beadchip. The most significant associ...

BACKGROUND One of the semen quality parameters use to determine fertility is the percentage of sperm that express normal morphology. Sperm head morphometry is also correlated with fertility. The objectives of this study were 1) to investigate the sperm morphology and normal sperm head morphometry of Thai native crossbred stallions, and 2) to compare our results with the characteristics of prove...

To test the hypothesis that prolactin mediates the increase in seminal volumes induced by sexual stimulation in stallions, semen was collected from six stallions every other day for 26 d. The last eight collection days were treatment days. For each stallion, four treatments were randomly assigned to the first four of the eight treatment collection days, and then repeated in reverse order on the...

Three experiments were conducted to determine 1) the relationship between prolactin and growth hormone (GH) secretion in mares and the response to GH-releasing hormone (GHRH), 2) whether plasma GH and prolactin concentrations differed among mares, stallions, and geldings, and 3) whether sexual differences existed after administration of GHRH and acute exercise. In Exp. 1, 10-min blood samples w...

The effect of steroidal anti-inflammatory drug dexamethasone on the changes of semen quality in stallions after endotoxin administration was studied. Three clinically healthy stallions were injected intravenously with endotoxin (LPS) from Escherichia coli 055:B5 at the dose of 0.3 μg/kg b.w.; while four stallions were treated with dexamethasone (0.069 mg/kg b.w., i.m.) 10 min before the adminis...