An experiment was conducted to determine the effects of high vs low body condition scores (BCS) produced by restricted feeding on reproductive characteristics, hormonal secretion, and leptin concentrations in mares during the autumnal transition and winter anovulatory period. Mares with BCS of 6.5 to 8.0 were maintained on pasture and/or grass hay, and starting in September, were full fed or re...

In 1938 Marker, Rohrmann, and Little (2) isolated from the urine of pregnant mares a new isomer of pregnanediol that they called uranediol. Ten years later, Klyne (3) obtained from the same source a sulfuric acid ester that yielded uranediol on acid hydrolysis. The structure of the free compound was determined by Klyne (4), who showed that it was a 17a-methyl-nhomo-5cr-androstane-3fl,17a&diol (...

The chronic degenerative endometritis (CDE) is recognised as directly related to age and infertility in the mare. In this study, 14 days post ovulation (PO) pregnancy rate was assessed 60 barren mares affected by CDE, submitted platelet-rich-plasma intrauterine infusion (PRPI) 24 hours PO. Data showed a significant positive effect of PRPI on chance become pregnant Kenney I-II CDE. overall PO 75...

Ovariectomized mares and mares with inactive ovaries may show signs of estrus. The reason behind this phenomenon is not clear; however, steroid hormones of adrenal origin have been suggested. Moreover, aberrant adrenal hormone production has been implied as a reason why some intact mares may change behavior. In the present study, the effect of ACTH on plasma levels of cortisol, progesterone, an...

Transrectal color and power Doppler ultrasonography was used to study uterine blood flow and perfusion in mares with and without uterine cysts. Vascular perfusion of the uterus and blood flow velocities, vascular perfusion, diameter, circumference, and area of a cross section of the mesometrial attachment were evaluated. To study the effect of internal cysts, two matched groups (cystic and cont...

The mare is the only non-primate species known to display estrous signs after ovariectomy and adrenal hormones have been implicated as a possible cause. Moreover, in several species, estradiol seems to have a stimulatory effect on the hypothalamic-pituitary-adrenal axis. The aim of the present study was to compare the effect of ACTH (tetracosactide) on pertinent hormones [cortisol, progesterone...

Abstract Nine pregnant mares (18.2 ± 0.7 y; 493.82 13 kg BW) were used to test the hypothesis that dietary supplementation of arginine would enhance placental vascularity and nutrient transport throughout gestation in aged mares. Mares balanced by age, BW, stallion pairing, randomly assigned one two treatments consisting supplemental L-arginine (50 mg/kg BW; n=5) or L-alanine (100 n=4; isonitro...

In stud management, broodmares are commonly fed concentrates in late pregnancy. This practice, however, was shown to correlate with an increased incidence of osteochondrosis in foals, which may be related to insulin sensitivity. We hypothesized that supplementation of the mare with barley in the last trimester of pregnancy alters the pre-weaning foal growth, glucose metabolism and osteoarticula...

This study aimed at determining the effect of the increase of foraging opportunities on the behaviour and welfare of breeding mares housed in individual boxes but allowed outside 6 h a day in a bare paddock. One hundred Arab breeding mares were divided into two groups of 50 according to the treatment and allowed outside in two bare paddocks at the same density (115 mare/ha) where water and shel...

Anti-Müllerian hormone (AMH) has been observed to decrease with the development of hemorrhagic anovulatory follicles (HAFs) in mares. Two studies were conducted to evaluate AMH concentration in mares with HAFs compared to seasonally anoestrous and cyclic mares, and to elucidate changes of AMH with the development of luteinised unruptured follicles (LUFs). In study 1, AMH and progesterone were e...