Abstract:
:The objective of this experiment was to develop a procedure for immunizing ewes against melatonin that would alter the effects of changing photoperiod on seasonal reproduction and prolactin secretion. Ewes were immunized against human serum albumin (HSA) as controls (n = 9) or a melatonin-human serum albumin conjugate (0.25 mg; n = 10) on December 14th (Day 0) and boosted 9 times. They were maintained on natural photoperiod and then transferred indoors and exposed to long days for 35 d, followed by short days for 146 d, long days for 93 d, and short days for a further 123 d. Antibody titers to melatonin (at a serum dilution of 1:1,250) were significantly higher in immunized ewes (27.3 +/- 6.6%) than controls (0.7 +/- 0.1%; P < 0.001). At the end of the experiment, antibody titers in immunized ewes (at dilution of 1:50) were higher in blood (43.7 +/- 8.2%) than in cerebrospinal fluid (10.8 +/- 3.9%; P < 0.05), and highly correlated (r2 = 0.746). Onset of the breeding season was advanced slightly after the second transfer from long to short days in immunized ewes (April 12 +/- 3 d) compared with controls (April 25 +/- 3 d; P < 0.05). Mean serum prolactin concentrations were lower (P < 0.05) in melatonin-immunized ewes compared with controls on natural photoperiod, after transfer from long to short days, during long days, and after the second transfer from long to short days. In conclusion, despite melatonin-immunization increasing antibody titers in blood and cerebrospinal fluid, and decreasing prolactin concentrations over much of the experiment, minimal effects on the timing of reproductive transitions in the ewes were evident. This discrepancy between the response of the prolactin and reproductive axes to melatonin immunization supports the hypothesis of a dual site of action of melatonin, with melatonin acting in the pituitary gland to mediate the effects of photoperiod on prolactin secretion and in the mediobasal hypothalamus to affect reproductive responses.
journal_name
Domest Anim Endocrinoljournal_title
Domestic animal endocrinologyauthors
O'Callaghan D,Sweeney T,Taylor L,Roblot G,Wylde Rdoi
10.1016/s0739-7240(99)00017-xsubject
Has Abstractpub_date
1999-05-01 00:00:00pages
207-17issue
4eissn
0739-7240issn
1879-0054pii
S0739-7240(99)00017-Xjournal_volume
16pub_type
杂志文章abstract::Receptors for LH (LHR) and FSH (FSHR) are expressed in the canine lower urinary tract (LUT). As gonadectomy results in an increase in plasma LH and FSH, the objective of this study was to determine whether there are any differences in the expression of LHR and FSHR in the LUT between intact and gonadectomised dogs. Fo...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2007.09.005
更新日期:2008-05-01 00:00:00
abstract::This study examined the role of the adrenergic system in the regulation of growth hormone (GH) secretion in sheep. Intravenous infusion of noradrenaline (0.5 microgram/kg per min for 2 hr) totally suppressed plasma GH concentrations. Concomitant treatment of animals with the beta-adrenergic antagonist propranolol comp...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/0739-7240(94)90026-4
更新日期:1994-04-01 00:00:00
abstract::Experimentally induced fever is accompanied by a variety of hormonal changes, and there is evidence to suggest that some of these responses may be mediated by prostaglandins. However, little is known about the endocrine effects of peripherally administered prostaglandins, especially in domesticated species. In this st...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/0739-7240(94)00021-r
更新日期:1995-04-01 00:00:00
abstract::beta-Adrenergic receptor (beta-AR) agonists increase muscle mass and decrease body fat in rodents and livestock. With oral administration, however, the effects of beta1-AR and beta2-AR can be different, depending on the species tested. We tested the effects of clenbuterol, a beta2-AR agonist, and ractopamine, a beta1/...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2003.08.004
更新日期:2004-01-01 00:00:00
abstract::The influence of phthalate esters di-2-ethylhexyl phthalate (DEHP) and mono-2-ethylhexyl phthalate (MEHP) on uterine prostaglandin (PGF2alpha and PGE2) and ovarian oxytocin secretion was investigated. Endometrial, granulosa, and luteal cells from cows on days 8-12 of the estrous cycle were treated with DEHP or MEHP (0...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2010.03.002
更新日期:2010-08-01 00:00:00
abstract::The ability of the neurohormone melatonin to ameliorate cryopreservation-induced damage to spermatozoa has been demonstrated in several domestic species. However, it is unclear how these protective effects are conferred, with improvements in sperm quality ambiguously attributed to the general antioxidant activity of m...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2020.106516
更新日期:2021-01-01 00:00:00
abstract::A remote infusion and blood collection device (Dracpac) was used on free-ranging red deer stags to deliver i.v. a range of ACTH1-24 doses and collect blood for cortisol determination. In Experiment 1, conducted in September, saline and 1, 4, and 16 IU ACTH/100 kg bodyweight were infused (n = 5-7 per treatment). In Exp...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/s0739-7240(96)00095-1
更新日期:1997-01-01 00:00:00
abstract::Gestagens and oestrogens are important regulators of pregnancy and parturition. The aim of the present study was the comparative quantification of steroidogenic transcripts in placenta and corpus luteum of cattle and sheep during pregnancy and post partum. Cyp19 transcript variants, derived from different promoters, a...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2004.01.008
更新日期:2004-08-01 00:00:00
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journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2018.04.002
更新日期:2018-07-01 00:00:00
abstract::This is a test-report of ghrelin levels in plasma and proventriculus, the glandular portion of the avian stomach, by using a specific radioimmunoassay for acylated ghrelin, as well as the expression of the ghrelin gene in the proventriculus after a 12-h fasting period followed by a 6-h feeding period with 6-day-old la...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2006.03.006
更新日期:2007-05-01 00:00:00
abstract::Tyrosine aminotransferase (TAT) catalyzes the transamination of tyrosine to p-hydroxyphenylpyruvate. Accumulation of tyrosine in the body due to a genetic mutation in the TAT gene causes tyrosomia type II in humans. The TAT gene is regarded as a model for studying steroid-inducible factors regulating a variety of biol...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2016.05.001
更新日期:2016-10-01 00:00:00
abstract::Growth process of animals is regulated by a multitude of physiological pathways among which components of the somatotropic axis play a key role. A number of severe, simply inherited growth disturbances have been identified in humans, laboratory and farm animals. These disorders are controlled by defective alleles at m...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章,评审
doi:10.1016/s0739-7240(00)00071-0
更新日期:2000-08-01 00:00:00
abstract::It is well established that GnRH can stimulate the release of LH and FSH in mammals. Two GnRHs have been found in the chicken hypothalamus, cGnRH-I and -II. There is controversy as to whether either peptide can stimulate release of FSH in birds. The present studies compared the ability of cGnRH-I and -II to stimulate ...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2005.10.002
更新日期:2006-08-01 00:00:00
abstract::Considering that recumbency can lead to a change in localization, detectability of distinct margins and thus measurement of the organs and reconstruction quality, it is of value to evaluate the effect of positioning on the objective evaluation of abdominal organs in computed tomography (CT). The objective of the prese...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2019.106406
更新日期:2020-07-01 00:00:00
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journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2014.09.001
更新日期:2015-01-01 00:00:00
abstract::The effects of increased postruminal supply of casein, corn starch, and soybean oil on plasma concentrations of the gastrointestinal hormones ghrelin and oxyntomodulin (OXM) were investigated. Four mid-lactation Holstein cows were used in a 4 x 4 Latin square. Treatments were continuous abomasal infusions (23 h/d) for...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2009.12.003
更新日期:2010-05-01 00:00:00
abstract::Crossbred ovariectomized ewes were treated with steroid therapies determined previously to be adequate (progesterone-primed) or inadequate (unprimed) for embryonic development in order to determine actual serum concentrations of replaced steroid hormones achieved by such treatments and to identify secreted endometrial...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/0739-7240(93)90017-6
更新日期:1993-04-01 00:00:00
abstract::In ruminants, both milking frequency and exogenous GH treatment affect milk production. In a previous report, we showed that the modulation of milk yield due to variations in milking frequency and GH treatment was associated with variations in mammary cell numbers. The aim of this study was to clarify the different me...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2004.04.002
更新日期:2004-11-01 00:00:00
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journal_title:Domestic animal endocrinology
pub_type: 杂志文章,随机对照试验
doi:10.1016/j.domaniend.2017.08.002
更新日期:2018-01-01 00:00:00
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journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/s0739-7240(99)00053-3
更新日期:1999-11-01 00:00:00
abstract::Three experiments were performed to study effects of decreased concentrations of estradiol-17 beta (E2) on lifespan and function of ensuing ovine corpora lutea (CL). In experiment 1, 52 follicles were collected from 10 ewes and placed into individual culture with 0 or .01 microCi 3H-androstenedione (10 ng; 3H-A) and 0...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/0739-7240(92)90019-t
更新日期:1992-10-01 00:00:00
abstract::In the dairy cow, puerperal uterine intra-luminal concentrations of PGE(2) are related to the establishment and severity of uterine infections. Here we evaluated whether the blood concentrations of PGE(2) and the gene transcription profiles of enzymes involved in its synthesis (cyclooxygenase-2 and prostaglandin E syn...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2008.07.001
更新日期:2008-10-01 00:00:00
abstract::An increasing demand for calcium during pregnancy and lactation can result in both clinical and subclinical hypocalcemia during the early lactation period in several mammalian species, in particular the dairy cow. Serotonin (5-HT) was recently identified as a regulator of lactation and bone turnover. The purpose of th...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2013.01.005
更新日期:2013-05-01 00:00:00
abstract::The influence of genetic selection for improved feed conversion (FC) and fast growth (GL) in broiler chickens, on the hepatic growth hormone receptor was investigated as a function of age. Selection for improved feed conversion resulted in lean chickens, whereas selection for fast growth resulted in fat chickens. Grow...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/0739-7240(93)90024-6
更新日期:1993-07-01 00:00:00
abstract::Fifteen cows (87 +/- 8 d in lactation; 641 +/- 33 kg BW) were randomly assigned to treatment and then subjected for 182 d to daily sc injection (1000 hr), in the cervical area, of saline (control), thyrotropin-releasing factor (TRF: 1 micrograms/kg BW), growth hormone-releasing factor (1-29)NH2 (GRF; 10 micrograms/kg ...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/0739-7240(91)90044-k
更新日期:1991-01-01 00:00:00
abstract::IL-2 has analgesic effects in both central and peripheral nervous systems. There are two distinct domains in IL-2 molecule mediating immunologic and analgesic activity, respectively. The analgesic domain of IL-2 may be composed of the 44th Phe, 45th Tyr, 107th Tyr, and 117th Phe residues that are located closely in th...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章,评审
doi:10.1016/s0739-7240(98)00026-5
更新日期:1998-09-01 00:00:00
abstract::Our objective was to examine the ability of thyroid releasing hormone (TRH) to stimulate not only the release of the thyroid hormones, but also prolactin (PRL) in the female pig. An experiment was conducted to determine the effect of dose and route of administration of TRH on the concentration of PRL and thyroxine (T4...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/0739-7240(90)90035-x
更新日期:1990-07-01 00:00:00
abstract::Highly prolific sows often experience peripartum hypophagia, resulting in decreased production rate. Leptin, ghrelin, and resistin are known as feed intake-regulating hormones in many species, but it is yet unknown how feeding strategy and body condition will affect these hormones around parturition in sows. In the pr...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2013.04.003
更新日期:2013-07-01 00:00:00
abstract::The embryo of the domestic fowl (Gallus domesticus) tenders one distinctive advantage over general mammalian models for investigating the development of the hypothalamo-pituitary-adrenocortical (HPA) axis. This is the relative simplicity with which the embryonic endocrine environment can be influenced without confound...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章,评审
doi:10.1016/j.domaniend.2004.01.001
更新日期:2004-05-01 00:00:00
abstract::Assay of blood progesterone (P4) is commonly practiced to determine the time of ovulation, diagnose luteal insufficiency, and predict time of parturition in bitches. Because of practical constraints, most blood samples cannot be assayed on site immediately after collection. The aim of this work was to evaluate the eff...
journal_title:Domestic animal endocrinology
pub_type: 杂志文章
doi:10.1016/j.domaniend.2013.07.002
更新日期:2013-10-01 00:00:00