BACKGROUND Feed intake affects the GH-IGF system and may be a key factor in determining the ovarian follicular growth rate. In fat mares, the plasma IGF-1 concentration is high with low GH and a quick follicular growth rate, in contrast to values observed in thin mares. Nothing is known regarding the long-term effects of differential feed intake on the IGF system. The objective of this experime...

The object of research was the Ukrainian massif breeding mares Orlov’s Trotter, registered on January 1, 2022 (n=194). 75.1% (145 mares) all were tested hippodromes. It determined that there low-level negative correlations between mares' agility indicators and body measurements. However, positive relations established analyzing record measurements different studs. at Kyiv Hippodrome with a high...

For all mares studied, a greater percentage of oviductal sperm were recovered from the ipsilateral oviduct following uterine horn insemination (77.3%) than resulted from uterine body insemination (53.8%). The number of oviductal sperm recovered from reproductively normal mares and mares with delayed uterine clearance was not different. Authors’ Addresses: Dept. of Large Animal Medicine & Surger...

One hundred anestrous mares (early February) were injected s.c. with implants containing 0, .9, 1.8, 3.6, or 5.4 mg of a GnRH analogue (goserelin acetate) in an attempt to induce ovarian cyclicity. Follicular activity and concentrations of progesterone and LH were determined every 3 d, or daily during estrus. In treated mares that ovulated, the interval to the second ovulation of the season was...

Intensive population management by means of fertility control has been shown to change the age profile of a wild horse herd. The primary change has been an increase in the number and percent of older animals, as expected, but also the appearance of new and older age classes. An examination of direct effects of fertility control on two groups of treated animals shows a significant increase in lo...

Equine follicle-stimulating hormone (eFSH) treatment increases embryo-recovery rate in donor mares. Recipient pregnancy rates per donor cycle were similar between eFSH-treated mares and non–eFSH-treated progesteroneand estradiol-synchronized donor mares. Authors’ address: Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus ...