Background: Kisspeptin has been demonstrated to affect the attainment of puberty in multiple species, presumably through its actions on GnRH and LH. It has previously been found there is an increase in expression of h...Background: Kisspeptin has been demonstrated to affect the attainment of puberty in multiple species, presumably through its actions on GnRH and LH. It has previously been found there is an increase in expression of hypothalamic in the rat and the monkey coincident with puberty. Whether a similar phenomenon occurs in the pig remains to be determined. The objectives of the current experiments were to determine 1) Plasma concentrations of estradiol-17β;2) Anterior pituitary gland concentrations of LH, IGF-I, kisspeptin, and anterior pituitary gland expression of LH-β and GnRH receptor;3) Mediobasal hypothalamus expression of Kiss1 and concentrations of kisspeptin during the peripubertal period in the gilt. Methods: Two experiments were performed, each with 25 crossbred gilts (151 d, 105 kg). Gilts were relocated and exposed to a mature boar beginning on d 1 and continuing throughout the experiments to naturally induce puberty. Gilts that stood immobile within 24 hours of slaughter were considered to have attained puberty. Plasma samples were collected on d 1, 3, and 7 of the first experiment and d 2, 4, 6, and 8 of the second experiment. Gilts were slaughtered on d 7 (experiment 1) or d 8 (experiment 2), when mediobasal hypothalamus (MBH), anterior pituitary glands (AP), and blood were collected. Relative expression of MBH Kiss1 and β-actin and AP GnRH receptor, LH-β, was determined using real-time reverse transcriptase PCR. Fold changes in relative expression were determined using the Relative Expression Software Tool. Hypothalamic and AP content of kisspeptin were determined by RIA and differences were determined using the GLIMMIX procedure of SAS. Results: Relative expression of Kiss1 was increased (P = 0.005) 2.2 fold in the gilts that had attained puberty in the first experiment, however, those that had attained puberty in the second were not different (P > 0.05) from gilts that had not. Relative expression of GnRH receptor was not different (P > 0.05) between treatments in both experiments. Relative expression of LH-β tended to be decreased (P = 0.09) 0.80 fold in gilts that attained puberty in the first experiment but was not different (P > 0.05) in gilts that attained puberty in the second experiment. AP concentrations of LH were not different (P > 0.05) between treatments in the first experiment and were decreased (P = 0.01) in gilts that attained puberty in the second experiment. AP concentrations of kisspeptin were not different (P > 0.05) in the first experiment but were increased (P = 0.04) in gilts that had attained puberty in the second experiment. MBH concentrations of kisspeptin were increased (P = 0.03) in gilts that had attained puberty in the first experiment but were not different (P > 0.05) between treatments in the second experiment. Conclusions: These data further support the role that MBH expression of Kiss1 and concentrations of kisspeptin and AP concentrations of kisspeptin fluctuate during the peripubertal period and may play a role in the attainment of puberty in the gilt.展开更多
<span style="font-family:Verdana;">Kisspeptin has been demonstrated to affect reproductive cyclicity and the attainment of puberty in multiple species, presumably through its actions on gonadotropin re...<span style="font-family:Verdana;">Kisspeptin has been demonstrated to affect reproductive cyclicity and the attainment of puberty in multiple species, presumably through its actions on gonadotropin releasing hormone and luteinizing hormone. Kisspeptin administration causes increased plasma concentrations of LH in pigs, sheep, and rats. The objective of this experiment was to evaluate changes in the hypothalamic kisspeptin system throughout the estrous cycle in gilts. Estrus was synchronized in forty crossbred gilts (191 d, 121 kg) and estrus detection was performed by exposing gilts to a mature boar. The first day gilts stood immobile was denoted d 1 of the estrous cycle. Blood samples were collected via jugular venipuncture on d 1, 4, 7, 9, 14, 16, and 19 of the estrous cycle. Ten animals were slaughtered on d 1, 9, 14, and 21 of the estrous cycle when medial basal hypothalami, anterior pituitary glands, and blood were collected. Relative expression of hypothalamic kisspeptin (KISS1), kisspeptin receptor (KISS1R), estrogen receptors-a, anterior pituitary gland GnRH receptor, </span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">-actin</span><span style="font-family:Verdana;" "="">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> and GAPDH was determined using real-time reverse transcriptase PCR. Fold changes in relative expression were determined using the Relative Expression Software Tool. Relative expression of KISS1 was increased (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> = 0.006) 3.2 fold on d 1 versus d 21 and 2.3 fold (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> = 0.003) on d 9 versus d 21 of the estrous cycle, but was not different (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> > 0.05) among the remaining days of the estrous cycle. Relative expression of estrogen receptor-b was decreased (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> = 0.05) 0.8 fold on d 9 versus d 21 and (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> = 0.005) 0.7 fold on d 14 versus d 21, but was not different (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> > 0.05) among the remaining days. Relative expression of anterior pituitary gland GnRH receptor was increased (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> < 0.01) on d 1 and 21 versus d 9 and 14. These data support the notion that medial basal hypothalamic expression of KISS1 changes throughout the estrous cycle and may influence reproductive cyclicity in the gilt.</span></span>展开更多
A study was conducted to determine if Se source fed during gestation and lactation affects passive transfer of immunoglobulins. Sixty days prior to breeding （d -60）, gilts were randomly assigned to one of three trea...A study was conducted to determine if Se source fed during gestation and lactation affects passive transfer of immunoglobulins. Sixty days prior to breeding （d -60）, gilts were randomly assigned to one of three treatments prior to breeding and throughout gestation： control （Control, no supplemental Se; n = 8）, inorganic Se （Inorganic Se, 0.3 ppm; n = 4） and organic Se （Organic Se, 0.3 ppm; n = 4）. Blood was collected on d -60, 57 and 113 of gestation and on d 21 of lactation and milk was collected at d 0, 1, 7, 14, and 21 of lactation. Blood was collected from piglets at d 0, 1, 7, 14, and 21 of age. Gilts fed organic Se had greater （P 〈 0.05） circulating concentrations of Se than Inorganic and Control gilts. Regardless of treatment, circulating concentrations of Se were greatest （P 〈 0.05） at d -60 compared to all other days. Serum concentrations of IgG were greatest （P 〈 0.05） in gilts at d 57 of gestation compared to d 113. Serum concentrations of IgA were greatest （P 〈 0.05） on d 113 of gestation and d 21 of lactation compared to d -60 and 57. Serum concentrations of IgM were greater （P 〈 0.05） at d 57 compared to d -60. Inorganic gilts had greater （P 〈 0.05） colostral and milk concentrations of IgG and IgM than Organic or Control gilts. Circulating concentrations of Se in piglets were greatest （P 〈 0.05） at d 14 and 21 of age compared to all other days. Piglets from gilts supplemented with organic Se had greater （P 〈 0.05） circulating concentrations of Se on d 1 versus piglets from gilts supplemented with no additional Se. The immunoglobulin concentrations of IgG, IgA, and IgM were lowest （P 〈 0.05） on d 0 and then different sources of Se did not affect the immunoglobulin ncreased when compared to d 1. The addition of concentrations in the gilt or piglet.展开更多
Administration of genistein to barrows increased anterior pituitary (AP) concentrations of IGF-I and LH and increased expression of AP IGF receptor. Whether similar changes occur in gilts remains to be determined. The...Administration of genistein to barrows increased anterior pituitary (AP) concentrations of IGF-I and LH and increased expression of AP IGF receptor. Whether similar changes occur in gilts remains to be determined. The objective of this experiment was to determine if short term administration of genistein increased expression of components of the AP IGF system and hypothalamic hormones and receptors involved in gonadotropin synthesis and/or release in the gilt. Sixteen crossbred gilts of similar weight (97.7 kg) were ovariectomized and assigned to either control (C;n = 8) or genistein (G;n = 8) groups. Genistein pigs received 800 mg of genistein in DMSO while C pigs received an equal volume of DMSO i.m. on day 0, 1, 2, and 3. Blood samples were obtained on day 0, 1, 2, and 3. Pigs were slaughtered on d 4 when blood, AP, and medial basal hypothalami (MBH) were collected. No difference was detected (P > 0.05) in AP concentrations of IGF-I or serum concentrations of IGF-I in C and G pigs. Anterior pituitary concentrations of LH were greater (P 0.05) in C and G pigs. Relative expression of AP IGFBP-5 and GnRHR was increased (P < 0.05) in G pigs compared with C pigs. Relative expression of AP LHβ did not differ between C and G pigs. Relative expression of MBH kisspeptin was greater (P < 0.01) in G pigs than C pigs. These data provided evidence that short term administration of genistein increased expression of hypothalamic and hypophyseal hormones in gilts which could influence subsequent reproduction.展开更多
文摘Background: Kisspeptin has been demonstrated to affect the attainment of puberty in multiple species, presumably through its actions on GnRH and LH. It has previously been found there is an increase in expression of hypothalamic in the rat and the monkey coincident with puberty. Whether a similar phenomenon occurs in the pig remains to be determined. The objectives of the current experiments were to determine 1) Plasma concentrations of estradiol-17β;2) Anterior pituitary gland concentrations of LH, IGF-I, kisspeptin, and anterior pituitary gland expression of LH-β and GnRH receptor;3) Mediobasal hypothalamus expression of Kiss1 and concentrations of kisspeptin during the peripubertal period in the gilt. Methods: Two experiments were performed, each with 25 crossbred gilts (151 d, 105 kg). Gilts were relocated and exposed to a mature boar beginning on d 1 and continuing throughout the experiments to naturally induce puberty. Gilts that stood immobile within 24 hours of slaughter were considered to have attained puberty. Plasma samples were collected on d 1, 3, and 7 of the first experiment and d 2, 4, 6, and 8 of the second experiment. Gilts were slaughtered on d 7 (experiment 1) or d 8 (experiment 2), when mediobasal hypothalamus (MBH), anterior pituitary glands (AP), and blood were collected. Relative expression of MBH Kiss1 and β-actin and AP GnRH receptor, LH-β, was determined using real-time reverse transcriptase PCR. Fold changes in relative expression were determined using the Relative Expression Software Tool. Hypothalamic and AP content of kisspeptin were determined by RIA and differences were determined using the GLIMMIX procedure of SAS. Results: Relative expression of Kiss1 was increased (P = 0.005) 2.2 fold in the gilts that had attained puberty in the first experiment, however, those that had attained puberty in the second were not different (P > 0.05) from gilts that had not. Relative expression of GnRH receptor was not different (P > 0.05) between treatments in both experiments. Relative expression of LH-β tended to be decreased (P = 0.09) 0.80 fold in gilts that attained puberty in the first experiment but was not different (P > 0.05) in gilts that attained puberty in the second experiment. AP concentrations of LH were not different (P > 0.05) between treatments in the first experiment and were decreased (P = 0.01) in gilts that attained puberty in the second experiment. AP concentrations of kisspeptin were not different (P > 0.05) in the first experiment but were increased (P = 0.04) in gilts that had attained puberty in the second experiment. MBH concentrations of kisspeptin were increased (P = 0.03) in gilts that had attained puberty in the first experiment but were not different (P > 0.05) between treatments in the second experiment. Conclusions: These data further support the role that MBH expression of Kiss1 and concentrations of kisspeptin and AP concentrations of kisspeptin fluctuate during the peripubertal period and may play a role in the attainment of puberty in the gilt.
文摘<span style="font-family:Verdana;">Kisspeptin has been demonstrated to affect reproductive cyclicity and the attainment of puberty in multiple species, presumably through its actions on gonadotropin releasing hormone and luteinizing hormone. Kisspeptin administration causes increased plasma concentrations of LH in pigs, sheep, and rats. The objective of this experiment was to evaluate changes in the hypothalamic kisspeptin system throughout the estrous cycle in gilts. Estrus was synchronized in forty crossbred gilts (191 d, 121 kg) and estrus detection was performed by exposing gilts to a mature boar. The first day gilts stood immobile was denoted d 1 of the estrous cycle. Blood samples were collected via jugular venipuncture on d 1, 4, 7, 9, 14, 16, and 19 of the estrous cycle. Ten animals were slaughtered on d 1, 9, 14, and 21 of the estrous cycle when medial basal hypothalami, anterior pituitary glands, and blood were collected. Relative expression of hypothalamic kisspeptin (KISS1), kisspeptin receptor (KISS1R), estrogen receptors-a, anterior pituitary gland GnRH receptor, </span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">-actin</span><span style="font-family:Verdana;" "="">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> and GAPDH was determined using real-time reverse transcriptase PCR. Fold changes in relative expression were determined using the Relative Expression Software Tool. Relative expression of KISS1 was increased (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> = 0.006) 3.2 fold on d 1 versus d 21 and 2.3 fold (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> = 0.003) on d 9 versus d 21 of the estrous cycle, but was not different (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> > 0.05) among the remaining days of the estrous cycle. Relative expression of estrogen receptor-b was decreased (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> = 0.05) 0.8 fold on d 9 versus d 21 and (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> = 0.005) 0.7 fold on d 14 versus d 21, but was not different (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> > 0.05) among the remaining days. Relative expression of anterior pituitary gland GnRH receptor was increased (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> < 0.01) on d 1 and 21 versus d 9 and 14. These data support the notion that medial basal hypothalamic expression of KISS1 changes throughout the estrous cycle and may influence reproductive cyclicity in the gilt.</span></span>
文摘A study was conducted to determine if Se source fed during gestation and lactation affects passive transfer of immunoglobulins. Sixty days prior to breeding （d -60）, gilts were randomly assigned to one of three treatments prior to breeding and throughout gestation： control （Control, no supplemental Se; n = 8）, inorganic Se （Inorganic Se, 0.3 ppm; n = 4） and organic Se （Organic Se, 0.3 ppm; n = 4）. Blood was collected on d -60, 57 and 113 of gestation and on d 21 of lactation and milk was collected at d 0, 1, 7, 14, and 21 of lactation. Blood was collected from piglets at d 0, 1, 7, 14, and 21 of age. Gilts fed organic Se had greater （P 〈 0.05） circulating concentrations of Se than Inorganic and Control gilts. Regardless of treatment, circulating concentrations of Se were greatest （P 〈 0.05） at d -60 compared to all other days. Serum concentrations of IgG were greatest （P 〈 0.05） in gilts at d 57 of gestation compared to d 113. Serum concentrations of IgA were greatest （P 〈 0.05） on d 113 of gestation and d 21 of lactation compared to d -60 and 57. Serum concentrations of IgM were greater （P 〈 0.05） at d 57 compared to d -60. Inorganic gilts had greater （P 〈 0.05） colostral and milk concentrations of IgG and IgM than Organic or Control gilts. Circulating concentrations of Se in piglets were greatest （P 〈 0.05） at d 14 and 21 of age compared to all other days. Piglets from gilts supplemented with organic Se had greater （P 〈 0.05） circulating concentrations of Se on d 1 versus piglets from gilts supplemented with no additional Se. The immunoglobulin concentrations of IgG, IgA, and IgM were lowest （P 〈 0.05） on d 0 and then different sources of Se did not affect the immunoglobulin ncreased when compared to d 1. The addition of concentrations in the gilt or piglet.
文摘Administration of genistein to barrows increased anterior pituitary (AP) concentrations of IGF-I and LH and increased expression of AP IGF receptor. Whether similar changes occur in gilts remains to be determined. The objective of this experiment was to determine if short term administration of genistein increased expression of components of the AP IGF system and hypothalamic hormones and receptors involved in gonadotropin synthesis and/or release in the gilt. Sixteen crossbred gilts of similar weight (97.7 kg) were ovariectomized and assigned to either control (C;n = 8) or genistein (G;n = 8) groups. Genistein pigs received 800 mg of genistein in DMSO while C pigs received an equal volume of DMSO i.m. on day 0, 1, 2, and 3. Blood samples were obtained on day 0, 1, 2, and 3. Pigs were slaughtered on d 4 when blood, AP, and medial basal hypothalami (MBH) were collected. No difference was detected (P > 0.05) in AP concentrations of IGF-I or serum concentrations of IGF-I in C and G pigs. Anterior pituitary concentrations of LH were greater (P 0.05) in C and G pigs. Relative expression of AP IGFBP-5 and GnRHR was increased (P < 0.05) in G pigs compared with C pigs. Relative expression of AP LHβ did not differ between C and G pigs. Relative expression of MBH kisspeptin was greater (P < 0.01) in G pigs than C pigs. These data provided evidence that short term administration of genistein increased expression of hypothalamic and hypophyseal hormones in gilts which could influence subsequent reproduction.
