[ Objective] To study the growth-development of Boer goats from embryo transplant. [ Method] With Boer goats from embryo transplant as the tested animals and natural breeding Boer goats born in the same period as CK, ...[ Objective] To study the growth-development of Boer goats from embryo transplant. [ Method] With Boer goats from embryo transplant as the tested animals and natural breeding Boer goats born in the same period as CK, the weight of Boer goats at birth and at the age of 1,3 and 6 months as well as the body size at the age of 3 and 6 months were investigated in this study, while their health conditions were also observed and recorded. [ Result] Under the normal feeding conditions, Boer goats from embryo transplant developed well at early stage, and their meat-using body type were also obvious. The average birth weight of bucks was （4.25±0.95） kg, and that of does was （3.74±0.10） kg. The average weight of bucks at the age of 6 months was （31.90 ±0.74） kg and that of was （25.90 ±0.67） kg. The daily gains of bucks and ewes from birth to 6 months of age were 153.64 and 123.11 g respectively, while their body length, body height and chest circumference increased obviously, and there was no significant difference in body weight or body size between them and natural breeding goats. [ Condusioa] The study lays a foundation for further studies on the breedinq and utilization of Boer noats from embryo transplant at early staae.展开更多
In this study, the ontogeny of body and the growth pattern of heart, brain, liver, lung, gizzard, glandular stomach and spleen of duck embryos were measured from embryonic day 2 to embryonic day 26. The results indica...In this study, the ontogeny of body and the growth pattern of heart, brain, liver, lung, gizzard, glandular stomach and spleen of duck embryos were measured from embryonic day 2 to embryonic day 26. The results indicated that the organs development trend of absolute growth and relative growth rate were almost synchrony, and both exhibited increase from embryonic day 20 to embryonic day 22. The whole growth intensity was from strong to weak with age increasing. The results of differentiation growth rate and the relative growth coefficient indicated that the brain and heart was premature while gizzard was serotinous; the liver, giz- zard, and spleen occupied the dominant position on embryonic days 16, 18 and 26. Therefore, duck embryos growing process was in a wave type state; different or- gans of duck embryos had different growth and development patterns; the relative growth index could supersede the differentiation growth rate preferably.展开更多
The influence of a growth factor supplemented serum-free system on the development, gene expression, and cryotolerance of in vitro pro- duced bovine embryos was investigated. To assess the embryo development and gene ...The influence of a growth factor supplemented serum-free system on the development, gene expression, and cryotolerance of in vitro pro- duced bovine embryos was investigated. To assess the embryo development and gene ex- pression in blastocysts, abattoir-derived oo- cytes (obtained from 3 - 10 or <3 mm follicles) were matured and fertilized in serum-free media and cultured in synthetic oviductal fluid sup- plemented with fetal bovine serum (FBS, 4%), epidermal growth factor (EGF, 10 ng/mL), insulin like growth factor-1 (IGF-1, 100 ng/mL), stem cell factor (SCF, 50 ng/mL) or combinations of the growth factors. Expressions of selected gene transcripts were relatively quantified in the d 8 blastocysts. To assess the cryotolerance, d 4 morulae (derived from 3 - 10 mm follicles and cultured with the supplementation of FBS or combinations of the growth factors) were vitri- fied, thawed and cultured (with respective sup- plementations). Total cell number and DNA frag- mentation in blastocysts derived from the vitri- fied morulae were assessed through TUNEL assay. The rate (%) of cleavage, blastocyst and expanded/hatched blastocyst did not differ among the culture medium supplementations within the follicle size of 3 - 10 mm (range 65.1 ± 4.3 - 75.4 ± 3.9;22.4 ± 3.9 - 36.4 ± 3.6;and 11.2 ± 2.9 - 23.3 ± 3.2, respectively) or <3 mm (range 59.3 ± 4.2 - 74.5 ± 3.7;15.0 ± 3.5 - 28.7 ± 4.5;and 9.3 ± 2.8 - 17.3 ± 2.7, respectively). Nevertheless, significantly lower (P < 0.05) cleavage and blastocyst rates with FBS and lower blastocyst rate with SCF supplementations were observed for the oocytes derived from <3 compared to 3 - 10 mm follicles. The expression patterns of BCL-2, BAX, HSP1A1, GJA1 and BIRC5 tran- scripts varied significantly (P < 0.05) in all cases, except for BIRC5 in the blastocysts derived from 3 - 10 mm follicles. Following thaw and culture, the development (%) of vitrified morulae into expanded/hatched blastocysts was lower (P < 0.01) with the supplementation of growth fac- tors compared to FBS. In contrast, total number of cells and DNA fragmentation index in blas- tocysts were not different among the treatments. In conclusion, the growth factor supplemented serum-free system was satisfactory for in vitro bovine embryo production. Nevertheless, the system was not efficient when embryos were derived from <3 mm follicles and cultured with SCF. Additionally, gene expression patterns and cryotolerance of the embryos were affected with the treatments of growth factors compared to serum.展开更多
Background： Brucella is a zoonotic Gram-negative pathogen that causes abortion and infertility in ruminants and humans. TLR4 is the receptor for LPS which can recognize Brucella and initiate antigen-presenting cell a...Background： Brucella is a zoonotic Gram-negative pathogen that causes abortion and infertility in ruminants and humans. TLR4 is the receptor for LPS which can recognize Brucella and initiate antigen-presenting cell activities that affect both innate and adaptive immunity. Consequently, transgenic sheep over-expressing TLR4 are an suitable model to investigate the effects of TLR4 on preventing Brucellosis. In this study, we generated transgenic sheep overexpressing TLR4 and aimed to evaluate the effects of different seasons（breeding and non-breeding season） on superovulation and the imported exogenous gene on growth.Results： In total of 43 donor ewes and 166 recipient ewes in breeding season, 37 donor ewes and 144 recipient ewes in non-breeding season were selected for super-ovulation and injected embryo transfer to generate transgenic sheep.Our results indicated the no. of embryos recovered of donors and the rate of pronuclear embryos did not show any significant difference between breeding and non-breeding seasons（P 〉 0.05）. The positive rate of exogenous TLR4 tested were 21.21 % and 22.58 % in breeding and non-breeding season by Southern blot. The expression level of TLR4 in the transgenic sheep was 1.5 times higher than in the non-transgenic group（P 〈 0.05）. The lambs overexpressing TLR4 had similar growth performance with non-transgenic lambs, and the blood physiological parameters of transgenic and non-transgenic were both in the normal range and did not show any difference.Conclusions： Here we establish an efficient platform for the production of transgenic sheep by the microinjection of pronuclear embryos during the whole year. The over-expression of TLR4 had no adverse effect on the growth of the sheep.展开更多
Using modified clay is one of the most promising methods for the mitigation of harmful algal blooms(HABs).However,the environmental impact of modified clay has become a subject of global concern.In this study,turbot(S...Using modified clay is one of the most promising methods for the mitigation of harmful algal blooms(HABs).However,the environmental impact of modified clay has become a subject of global concern.In this study,turbot(Scophthalmus maximus L.)embryos were used as a model to assess the effect of modified clay on this sensitive stage of fish development.Results show that the 24 and 48h LC 50(median lethal concentrations)of the modified clay were 1.70 and 1.65 g/L,and the safe concentration was 0.47 g/L,which is much higher than the concentration used to treat HAB.The modified clay did not affect significantly the hatchability of turbot embryos but when the concentration exceeded 0.50 g/L,the deformity rate of newly hatched larvae increased significantly.The total length,specific growth rate(SGR)and yolk sac absorption rate of larvae reached their peaks at 0.50 g/L and then gradually decreased as the concentration of modified clay increased.Therefore,a moderate amount of modified clay does not harm the survival and hatching of turbot embryos,or the growth and development of newly hatched larvae.展开更多
Neural stem cells promote neuronal regeneration and repair of brain tissue after injury,but have limited resources and proliferative ability in vivo.We hypothesized that nerve growth factor would promote in vitro prol...Neural stem cells promote neuronal regeneration and repair of brain tissue after injury,but have limited resources and proliferative ability in vivo.We hypothesized that nerve growth factor would promote in vitro proliferation of neural stem cells derived from the tree shrews,a primate-like mammal that has been proposed as an alternative to primates in biomedical translational research.We cultured neural stem cells from the hippocampus of tree shrews at embryonic day 38,and added nerve growth factor（100 μg/L） to the culture medium.Neural stem cells from the hippocampus of tree shrews cultured without nerve growth factor were used as controls.After 3 days,fluorescence microscopy after DAPI and nestin staining revealed that the number of neurospheres and DAPI/nestin-positive cells was markedly greater in the nerve growth factor-treated cells than in control cells.These findings demonstrate that nerve growth factor promotes the proliferation of neural stem cells derived from tree shrews.展开更多
Since the first report on the successful deep cryopreservation of mam-malian embryos in 1972,slow progressing cooling rate has been employ-ed in conventional embryos-freezing techniques;while more recent studieson fre...Since the first report on the successful deep cryopreservation of mam-malian embryos in 1972,slow progressing cooling rate has been employ-ed in conventional embryos-freezing techniques;while more recent studieson freezing preimplantation embryos have focussed on the simplificationof cooling and thawing procedures and improvement of viability of embr-yos.Dimethylsulfoxide (DMSO)has been used as an effective cryoprotec-tant for freezing human and other mammalian embryos.It has been foundthat glycerol and other alcohols are effective to protect embryos fromcryoinjury展开更多
Somatic embryogenesis was achieved in two oil yielding tropical tree species i.e. Simarouba glauca & Azadirachta indica using immature zygotic embryos as explants on Murashige and Skoog (MS) medium supplemented wi...Somatic embryogenesis was achieved in two oil yielding tropical tree species i.e. Simarouba glauca & Azadirachta indica using immature zygotic embryos as explants on Murashige and Skoog (MS) medium supplemented with 0.5 – 1.5 mg/l benzylaminopurine (BA) and 2.0 - 3.0 mg/l NAA (1-napthaleneacetic acid) or 2, 4-D (2,4-dichlorophenoxyacetic acid) and 3% sucrose. MS medium containing 1.0 mg/l BA and 2.0 mg/l NAA was noted to be the most effective in inducing friable embryogenic callus (FEC) in Simarouba glauca;the number of somatic embryos per culture varied in MS medium supplemented with 1.0 – 1.5 mg/l BA and 1.0 mg/l NAA. In Azadirachta indica, somatic embryos developed on MS medium supplemented with 0.5 mg/l BA and 1.5 – 2.0 mg/l 2,4-D which were in various shapes and sizes after the first subculture on MS medium supplemented with 0.25 mg/l abscisic acid. The somatic embryos which developed shoots were isolated and rooted in 1/2 strength MS medium supplemented with 0.25 mg/l abscisic acid and 2% sucrose. About 25% of embryos germinated within 20 days of culture in case of Simarouba glauca and 62% in Azadirachta indica. The somatic embryo-derived plantlets were transferred to the field after being hardened in the climate controlled hardening chamber.展开更多
We have shown that an injection of sustained release growth hormone (GH), given just prior to breeding, results in lambs that are 25% heavier at birth, with an altered body composition as evidenced by an increased abd...We have shown that an injection of sustained release growth hormone (GH), given just prior to breeding, results in lambs that are 25% heavier at birth, with an altered body composition as evidenced by an increased abdominal girth, but no difference in crown rump length. The mechanisms by which these differences occur from a single periconceptional injection are not yet known. Therefore, the objective of this experiment was to determine the effect of an injection of GH given prior to breeding on the composition of the uterine luminal environment and the embryo at the time of blastocyst. Ewes were synchronized with two injections of prostaglandin F2α given eight days apart. On the day of the second injection, ewes were randomly assigned to be given an injection of sustained release GH or remain as controls and penned with a ram. On day 6.5 following breeding embryos were collected. Prior to surgery a jugular blood sample was taken to determine plasma progesterone and urea concentration. The uterine content of urea, prostaglandin F2α, prostaglandin E2, transforming growth factor β-1 (TGF β), and nitric oxide metabolites were measured. Collected embryos were differentially stained to calculate a trophectoderm to inner cell mass ratio. The concentration of progesterone in maternal plasma was greater in the treated group compare to controls, but blood urea nitrogen was not different between groups. The uterine content of urea in the GH group was lower than that of the control group. There was a trend for TGF β to be increased in the GH treated group compared to control (P = 0.07). There was no difference (P > 0.05) in the total uterine content prostaglandin F2α, prostaglandin E2 or nitric oxide metabolites. The trophectoderm to inner cell mass ratio was not different between treatment groups. Thus, we suggest that the observed difference in fetal development following periconceptional growth hormone administration just prior to breeding may be the result of an alteration in the uterine luminal environment, which may alter the cellular program of the conceptus and later development beyond the embryonic stage.展开更多
A newly efficient protocol has been established for high frequency somatic embryogenesis through callus culture of Coelogyne cristata. The best frequency of callusing was obtained from leaf segments (3-5 mm) cultured ...A newly efficient protocol has been established for high frequency somatic embryogenesis through callus culture of Coelogyne cristata. The best frequency of callusing was obtained from leaf segments (3-5 mm) cultured on the MS medium supplemented with 2 mg?L–1 2,4-D and 2 mg?L–1 BA combination. A negative effect of coconut water was ob-served on the callus induction medium. When callus lines no. 4, 6 and 8 induced from leaf segments were sub-cultured separately on ? MS and MS media containing AC (1-3 g?L–1), formation of somatic embryos was found. However, percentages of embryo formation and the number of embryos per explants were strongly affected by media and callus lines used. The effect of 1/2 MS media is definitely better than MS medium for somatic embryogenesis from the selected lines of leaf derived callus. Among the callus lines, line no. 4 is the best for somatic embryogenesis followed by line no. 6 and 8. The somatic embryos converted into healthy plants with well developed shoots on the same media. The plant-lets were transferred to 1/2 MS medium containing 1 g?L–1 AC for plant regeneration until 8 weeks of culture and successfully acclimatized in the greenhouse.展开更多
Zygotic embryos tissues have found to be more responsive explants for clonal propagation of coconut. In the present study, the feasibility of using zygotic embryos explants for clonal propagation of a local coconut va...Zygotic embryos tissues have found to be more responsive explants for clonal propagation of coconut. In the present study, the feasibility of using zygotic embryos explants for clonal propagation of a local coconut variety MATAG F2 was assessed. Callus was induced by incorporating of cytokinin and auxin into the medium. The sliced embryos explants were immersed in 1 M maltose for 60 mins, then with 0.05 M maltose for 1 min and followed by 0.01 M maltose for 5 mins was the best for prevention of phenolic compounds excretion. The callus formation depended on the concentration of 2,4-D in the media and the best effect was observed with the high level (2,4-D and BAP) tested. Attempts at inducing multiple shoot from the zygotic embryos callus were unsuccessful. No multiple shoots was present;most of the callus became root structure.展开更多
基金supported by Talent Research Foundation of Henan University of Technology (09001095)Scientific and Technological Project of Henan Province " Research and Demonstration of Supporting Production Technology Systemfor High-quality Funiu White Goats" (072102130004)
文摘[ Objective] To study the growth-development of Boer goats from embryo transplant. [ Method] With Boer goats from embryo transplant as the tested animals and natural breeding Boer goats born in the same period as CK, the weight of Boer goats at birth and at the age of 1,3 and 6 months as well as the body size at the age of 3 and 6 months were investigated in this study, while their health conditions were also observed and recorded. [ Result] Under the normal feeding conditions, Boer goats from embryo transplant developed well at early stage, and their meat-using body type were also obvious. The average birth weight of bucks was （4.25±0.95） kg, and that of does was （3.74±0.10） kg. The average weight of bucks at the age of 6 months was （31.90 ±0.74） kg and that of was （25.90 ±0.67） kg. The daily gains of bucks and ewes from birth to 6 months of age were 153.64 and 123.11 g respectively, while their body length, body height and chest circumference increased obviously, and there was no significant difference in body weight or body size between them and natural breeding goats. [ Condusioa] The study lays a foundation for further studies on the breedinq and utilization of Boer noats from embryo transplant at early staae.
基金Supported by National Natural Science Foundation of China(31172194)Key Technology Support Program of Jiangsu Province(BE2014362)
文摘In this study, the ontogeny of body and the growth pattern of heart, brain, liver, lung, gizzard, glandular stomach and spleen of duck embryos were measured from embryonic day 2 to embryonic day 26. The results indicated that the organs development trend of absolute growth and relative growth rate were almost synchrony, and both exhibited increase from embryonic day 20 to embryonic day 22. The whole growth intensity was from strong to weak with age increasing. The results of differentiation growth rate and the relative growth coefficient indicated that the brain and heart was premature while gizzard was serotinous; the liver, giz- zard, and spleen occupied the dominant position on embryonic days 16, 18 and 26. Therefore, duck embryos growing process was in a wave type state; different or- gans of duck embryos had different growth and development patterns; the relative growth index could supersede the differentiation growth rate preferably.
文摘The influence of a growth factor supplemented serum-free system on the development, gene expression, and cryotolerance of in vitro pro- duced bovine embryos was investigated. To assess the embryo development and gene ex- pression in blastocysts, abattoir-derived oo- cytes (obtained from 3 - 10 or <3 mm follicles) were matured and fertilized in serum-free media and cultured in synthetic oviductal fluid sup- plemented with fetal bovine serum (FBS, 4%), epidermal growth factor (EGF, 10 ng/mL), insulin like growth factor-1 (IGF-1, 100 ng/mL), stem cell factor (SCF, 50 ng/mL) or combinations of the growth factors. Expressions of selected gene transcripts were relatively quantified in the d 8 blastocysts. To assess the cryotolerance, d 4 morulae (derived from 3 - 10 mm follicles and cultured with the supplementation of FBS or combinations of the growth factors) were vitri- fied, thawed and cultured (with respective sup- plementations). Total cell number and DNA frag- mentation in blastocysts derived from the vitri- fied morulae were assessed through TUNEL assay. The rate (%) of cleavage, blastocyst and expanded/hatched blastocyst did not differ among the culture medium supplementations within the follicle size of 3 - 10 mm (range 65.1 ± 4.3 - 75.4 ± 3.9;22.4 ± 3.9 - 36.4 ± 3.6;and 11.2 ± 2.9 - 23.3 ± 3.2, respectively) or <3 mm (range 59.3 ± 4.2 - 74.5 ± 3.7;15.0 ± 3.5 - 28.7 ± 4.5;and 9.3 ± 2.8 - 17.3 ± 2.7, respectively). Nevertheless, significantly lower (P < 0.05) cleavage and blastocyst rates with FBS and lower blastocyst rate with SCF supplementations were observed for the oocytes derived from <3 compared to 3 - 10 mm follicles. The expression patterns of BCL-2, BAX, HSP1A1, GJA1 and BIRC5 tran- scripts varied significantly (P < 0.05) in all cases, except for BIRC5 in the blastocysts derived from 3 - 10 mm follicles. Following thaw and culture, the development (%) of vitrified morulae into expanded/hatched blastocysts was lower (P < 0.01) with the supplementation of growth fac- tors compared to FBS. In contrast, total number of cells and DNA fragmentation index in blas- tocysts were not different among the treatments. In conclusion, the growth factor supplemented serum-free system was satisfactory for in vitro bovine embryo production. Nevertheless, the system was not efficient when embryos were derived from <3 mm follicles and cultured with SCF. Additionally, gene expression patterns and cryotolerance of the embryos were affected with the treatments of growth factors compared to serum.
基金supported by grants from National Transgenic Creature Breeding Grand Project (2014ZX08008-005)
文摘Background： Brucella is a zoonotic Gram-negative pathogen that causes abortion and infertility in ruminants and humans. TLR4 is the receptor for LPS which can recognize Brucella and initiate antigen-presenting cell activities that affect both innate and adaptive immunity. Consequently, transgenic sheep over-expressing TLR4 are an suitable model to investigate the effects of TLR4 on preventing Brucellosis. In this study, we generated transgenic sheep overexpressing TLR4 and aimed to evaluate the effects of different seasons（breeding and non-breeding season） on superovulation and the imported exogenous gene on growth.Results： In total of 43 donor ewes and 166 recipient ewes in breeding season, 37 donor ewes and 144 recipient ewes in non-breeding season were selected for super-ovulation and injected embryo transfer to generate transgenic sheep.Our results indicated the no. of embryos recovered of donors and the rate of pronuclear embryos did not show any significant difference between breeding and non-breeding seasons（P 〉 0.05）. The positive rate of exogenous TLR4 tested were 21.21 % and 22.58 % in breeding and non-breeding season by Southern blot. The expression level of TLR4 in the transgenic sheep was 1.5 times higher than in the non-transgenic group（P 〈 0.05）. The lambs overexpressing TLR4 had similar growth performance with non-transgenic lambs, and the blood physiological parameters of transgenic and non-transgenic were both in the normal range and did not show any difference.Conclusions： Here we establish an efficient platform for the production of transgenic sheep by the microinjection of pronuclear embryos during the whole year. The over-expression of TLR4 had no adverse effect on the growth of the sheep.
基金Supported by the National Key Research and Development Program of China(No.2017YFC1404300)the NSFC-Shandong Joint Fund for Marine Science Research Center(No.U1606404)the National Key Research and Development Program of China(No.2016YFE0101500)
文摘Using modified clay is one of the most promising methods for the mitigation of harmful algal blooms(HABs).However,the environmental impact of modified clay has become a subject of global concern.In this study,turbot(Scophthalmus maximus L.)embryos were used as a model to assess the effect of modified clay on this sensitive stage of fish development.Results show that the 24 and 48h LC 50(median lethal concentrations)of the modified clay were 1.70 and 1.65 g/L,and the safe concentration was 0.47 g/L,which is much higher than the concentration used to treat HAB.The modified clay did not affect significantly the hatchability of turbot embryos but when the concentration exceeded 0.50 g/L,the deformity rate of newly hatched larvae increased significantly.The total length,specific growth rate(SGR)and yolk sac absorption rate of larvae reached their peaks at 0.50 g/L and then gradually decreased as the concentration of modified clay increased.Therefore,a moderate amount of modified clay does not harm the survival and hatching of turbot embryos,or the growth and development of newly hatched larvae.
基金supported by a grant from the National Key Technology Research and Development Program of the Ministry of Science and Technology of China,No.2014BAI01B00
文摘Neural stem cells promote neuronal regeneration and repair of brain tissue after injury,but have limited resources and proliferative ability in vivo.We hypothesized that nerve growth factor would promote in vitro proliferation of neural stem cells derived from the tree shrews,a primate-like mammal that has been proposed as an alternative to primates in biomedical translational research.We cultured neural stem cells from the hippocampus of tree shrews at embryonic day 38,and added nerve growth factor（100 μg/L） to the culture medium.Neural stem cells from the hippocampus of tree shrews cultured without nerve growth factor were used as controls.After 3 days,fluorescence microscopy after DAPI and nestin staining revealed that the number of neurospheres and DAPI/nestin-positive cells was markedly greater in the nerve growth factor-treated cells than in control cells.These findings demonstrate that nerve growth factor promotes the proliferation of neural stem cells derived from tree shrews.
文摘Since the first report on the successful deep cryopreservation of mam-malian embryos in 1972,slow progressing cooling rate has been employ-ed in conventional embryos-freezing techniques;while more recent studieson freezing preimplantation embryos have focussed on the simplificationof cooling and thawing procedures and improvement of viability of embr-yos.Dimethylsulfoxide (DMSO)has been used as an effective cryoprotec-tant for freezing human and other mammalian embryos.It has been foundthat glycerol and other alcohols are effective to protect embryos fromcryoinjury
文摘Somatic embryogenesis was achieved in two oil yielding tropical tree species i.e. Simarouba glauca & Azadirachta indica using immature zygotic embryos as explants on Murashige and Skoog (MS) medium supplemented with 0.5 – 1.5 mg/l benzylaminopurine (BA) and 2.0 - 3.0 mg/l NAA (1-napthaleneacetic acid) or 2, 4-D (2,4-dichlorophenoxyacetic acid) and 3% sucrose. MS medium containing 1.0 mg/l BA and 2.0 mg/l NAA was noted to be the most effective in inducing friable embryogenic callus (FEC) in Simarouba glauca;the number of somatic embryos per culture varied in MS medium supplemented with 1.0 – 1.5 mg/l BA and 1.0 mg/l NAA. In Azadirachta indica, somatic embryos developed on MS medium supplemented with 0.5 mg/l BA and 1.5 – 2.0 mg/l 2,4-D which were in various shapes and sizes after the first subculture on MS medium supplemented with 0.25 mg/l abscisic acid. The somatic embryos which developed shoots were isolated and rooted in 1/2 strength MS medium supplemented with 0.25 mg/l abscisic acid and 2% sucrose. About 25% of embryos germinated within 20 days of culture in case of Simarouba glauca and 62% in Azadirachta indica. The somatic embryo-derived plantlets were transferred to the field after being hardened in the climate controlled hardening chamber.
文摘We have shown that an injection of sustained release growth hormone (GH), given just prior to breeding, results in lambs that are 25% heavier at birth, with an altered body composition as evidenced by an increased abdominal girth, but no difference in crown rump length. The mechanisms by which these differences occur from a single periconceptional injection are not yet known. Therefore, the objective of this experiment was to determine the effect of an injection of GH given prior to breeding on the composition of the uterine luminal environment and the embryo at the time of blastocyst. Ewes were synchronized with two injections of prostaglandin F2α given eight days apart. On the day of the second injection, ewes were randomly assigned to be given an injection of sustained release GH or remain as controls and penned with a ram. On day 6.5 following breeding embryos were collected. Prior to surgery a jugular blood sample was taken to determine plasma progesterone and urea concentration. The uterine content of urea, prostaglandin F2α, prostaglandin E2, transforming growth factor β-1 (TGF β), and nitric oxide metabolites were measured. Collected embryos were differentially stained to calculate a trophectoderm to inner cell mass ratio. The concentration of progesterone in maternal plasma was greater in the treated group compare to controls, but blood urea nitrogen was not different between groups. The uterine content of urea in the GH group was lower than that of the control group. There was a trend for TGF β to be increased in the GH treated group compared to control (P = 0.07). There was no difference (P > 0.05) in the total uterine content prostaglandin F2α, prostaglandin E2 or nitric oxide metabolites. The trophectoderm to inner cell mass ratio was not different between treatment groups. Thus, we suggest that the observed difference in fetal development following periconceptional growth hormone administration just prior to breeding may be the result of an alteration in the uterine luminal environment, which may alter the cellular program of the conceptus and later development beyond the embryonic stage.
文摘A newly efficient protocol has been established for high frequency somatic embryogenesis through callus culture of Coelogyne cristata. The best frequency of callusing was obtained from leaf segments (3-5 mm) cultured on the MS medium supplemented with 2 mg?L–1 2,4-D and 2 mg?L–1 BA combination. A negative effect of coconut water was ob-served on the callus induction medium. When callus lines no. 4, 6 and 8 induced from leaf segments were sub-cultured separately on ? MS and MS media containing AC (1-3 g?L–1), formation of somatic embryos was found. However, percentages of embryo formation and the number of embryos per explants were strongly affected by media and callus lines used. The effect of 1/2 MS media is definitely better than MS medium for somatic embryogenesis from the selected lines of leaf derived callus. Among the callus lines, line no. 4 is the best for somatic embryogenesis followed by line no. 6 and 8. The somatic embryos converted into healthy plants with well developed shoots on the same media. The plant-lets were transferred to 1/2 MS medium containing 1 g?L–1 AC for plant regeneration until 8 weeks of culture and successfully acclimatized in the greenhouse.
文摘Zygotic embryos tissues have found to be more responsive explants for clonal propagation of coconut. In the present study, the feasibility of using zygotic embryos explants for clonal propagation of a local coconut variety MATAG F2 was assessed. Callus was induced by incorporating of cytokinin and auxin into the medium. The sliced embryos explants were immersed in 1 M maltose for 60 mins, then with 0.05 M maltose for 1 min and followed by 0.01 M maltose for 5 mins was the best for prevention of phenolic compounds excretion. The callus formation depended on the concentration of 2,4-D in the media and the best effect was observed with the high level (2,4-D and BAP) tested. Attempts at inducing multiple shoot from the zygotic embryos callus were unsuccessful. No multiple shoots was present;most of the callus became root structure.
