Twenty-two mature pluriparous beef cows were randomly assigned to one of six treatments in a 2 X 3 factorial experiment in order to study the role of suckling and ovarian factors on control of the tonic and episodic release of luteinizing hormone (LH). Twelve cows remained intact (INT) and 10 were ovariectomized (OVX) within 4 days following the day of parturition (Day 0). The suckling intensit...

Seven yearling Holstein bulls were given 0, 20, 40, 60, 80, 100 and 200 micrograms NIH-LH-B9 during a 7-day complete Latin square design experiment. Treatments were administered via jugular cannulas at 0900 hr, and blood was collected at 60, 30 and 0 min before treatment, at 15-min intervals for 3 hr after treatment and at 30-min intervals from 3 to 7 hr after treatment. Luteinizing hormone (LH...

Reproductive parameters were evaluated in 19 and 14 estrous beagles that received 100 µg of gonadotropin-releasing hormone (GnRH) and saline treatment, respectively, on the day of luteinizing hormone (LH) surge (Day 0; estimated by serial progesterone assay) and balloon catheter-aided single transvaginal artificial insemination of frozen semen on Day 5. Although the conception rate and litter s...

To determine if glucose availability modulates the timing of the positive feedback action of oestrogen on gonadotropin secretion, we monitored the estradiol-induced luteinizing hormone (LH) surge in sheep (n = 5/group) made transiently hypoglycemic by insulin. Experiment 1 determined an effective insulin treatment, one which would depress tonic LH secretion. Two injections of insulin (5 IU/kg i...

The hypothesis that luteinizing hormone (LH) secretion in prepubertal females is responsive to estradiol negative feedback and that decreased feedback occurs as puberty approaches was tested in heifers. In the first experiment, seven heifers were maintained prepubertal by dietary energy restriction until 508 days of age (Day 0). All heifers were placed on a high-energy diet on Day 0 at which ti...

The aim of the present study was to clarify the effect of kisspeptin-10 on LH secretion in prepubertal ewes. In experiment 1, prepubertal ewes fitted with indwelling jugular catheters were randomly assigned to receive 0, 0.5, 1 or 2 mg of kisspeptin-10 dissolved in saline, and serial blood samples were collected at 15-min intervals for 180 min to analyze the response curves of LH after injectio...

Abstract Study question Does low pretrigger LH in GnRH antagonist cycles affect the blastulation rates and cumulative live birth rates? Summary answer Low does not frozen embryo transfer cycles. What is known already • There conflicting evidence that stimulated with recombinant FSH, serum may effect negatively pregnancy outcomes fresh transfer.(Benmachiche et al 2019). Whether observed of on or...

In this paper we provide a new arithmetic characterization of the levels of the log-time hierarchy (LH). We define arithmetic classes Σ k and Π log k that correspond to Σk-LOGTIME and Πk-LOGTIME respectively. We break Σ k and Π log k into natural hierarchies of subclasses Σm·log k and Π m·log k . We then define bounded arithmetic deduction systems (TΣ k ) ′ whose U{|id|}B(Σ log k )-definable fu...

A series of homometallic dinuclear lanthanide complexes containing nonequivalent metal centers [Ln(2)(LH(2))(LH)(CH(3)OH)(N(3))]·xMeOH·yH(2)O [1, Ln = Dy(III), x 0, y 2; 2, Tb(III), 1, 1] have been synthesized [LH(4) 6-((bis(2-hydroxyethyl)amino)-N’-(2-hydroxybenzylidene)picolinohydrazide] and characterized. The assembly contains two different types nine-coordinated centers, because the binding...