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低死亡率和较高的饲料利用率 ,看来是鸡抗氧化状态得到改善的结果。增高日粮维生素E的含量并应用有机硒可减少肺高压 (腹水症 )引起的死亡。 相似文献
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J. F. Roche 《Veterinary research communications》1977,1(1):121-129
Luteolytic doses of the Tham salt of PGF2 or one of its synthetic analogues cause premature regression of, the corpus luteum between the 5th and the 16th day of the oestrous cycle, inducing, 2 to 4 days after the injection, endcrine changes similar to a normal lultolysis and oestrus. After insemination at the time of this oestrus or at predefined times 72 to 96 hours after the injection, fertility is similar to that in controls. The paractical use of prostaglandins for the synchronization of oestrus in a herd of randomly cyclic animals takes account of the fact that only animals between the 5th and the 16th day respond to an injection. Various techniques are proposed, notably a double injection with an interval of 10–12 days.
Kurzfassung Luteolytische Dosen eines Tham'schen Salzes von PGF2, oder einer dessen synthetischen Analogen bringen vorzeitige Regressionen des corporis lutei zwischen dem 5ten und dem 16ten Tage hervor. Als Folge dieser Regressionen entwickeln sich innerhalb 2 bis 4 Tage nach der Einspritzung endokrine Veränderungen, die der normalen Luteolyse und Brunst ähnlich sind. Nach einer Besamung zur Zeit dieser Brunst oder zu vorherbestimmten Zeiten und zwar 72 und 92 Stunden nach der Einspritzung wird die gleiche Frunchtbarkeit wie in unbehandelten Kontrollen beobachtet. Nur ein Teil einer zyklischen Herde reagiert auf Prostaglandin, und es werden daher verschiedene Methoden der Viehwirtschaftsführung zur Überwindung dieses Problems erörtert, wie auch den Gebrauch einer Doppeleinspritzung von Prostaglandin mit einem 10 bis 12 tägigen Abstand zwischen den Behandlungen.
Resume Les doses lutéolytiques de sel Tham de PGF2 ou d'un de ses analogues synthetiques causent une reégression prématurée du corps jaunne entre le 5ème et le 16ème jour du cycle provoquant, 2 à 4 jours après l'injections, des changements endocriniens semblales à une lutéolyse normale et à un oestrus. Après l'insémination au moment de cet oestrus ou à des temps prédéfinis de 72 à 96 heures après l'injection, la fertilité est semblable à celle des animaux témoins non traités. L'utilisation pratique des prostaß-landinesd pour la synchronisation des chaleurs dans un troupoeau de femelles cyclées tient compte du fait que seules les femelles entre le 5ème et 16ème jour du cycle répondent à une injection. Différentes techniques sont proposées, notamment la double injection à 10–12 jours d'intervalle.
Riassunto Le dosi luteolitiche del sale Them PGF2 o di uno dei suoi analoghi sintetioi causano una regressione prematura del corpo giallo tra il 5o ed il 16o giorno del ciclo provooando, dopo un periodo che va dai 2 ai 4 giorni dall'iniezione, dei cambiamenti endocrini simili ad una luteolisi normale o ad un estro. Dopo l'inseminazine, nel momento di questo estro oppure in tempi predeterminati, in un periodo compreso tra 72 e 96 ore dopo l'iniezione, la fertilità è simile a quella jdegli animali di controllo non trattati. L'utilizzazione poratioa della prostaglandine per la sincronizzazione dei oalori in una mandria di femmine cicliche dimostra che le femmine rispondono all'iniezione soltanto tra il 5o ed 16o giorno del ciclo. Si propongono diverse techniche, in poarticolasre la doppia iniezione ad un intervallo di 10–12 giorni.相似文献
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Melatonin reduces apoptotic cells,SOD2 and HSPB1 and improves the in vitro production and quality of bovine blastocysts 下载免费PDF全文
TC Marques EC da Silva Santos TO Diesel LO Leme CF Martins MAN Dode BG Alves FPH Costa EB de Oliveira ML Gambarini 《Reproduction in domestic animals》2018,53(1):226-236
Effects of adding different concentrations of melatonin (10?7, 10?9 and 10?11 M) to maturation (Experiment 1; Control, IVM + 10?7, IVM + 10?9, IVM + 10?11) and culture media (Experiment 2; Control, IVC + 10?7, IVC + 10?9, IVC + 10?11) were evaluated on in vitro bovine embryonic development. The optimal concentration of melatonin (10?9 M) from Experiments 1–2 was tested in both maturation and/or culture media of Experiment 3 (Control, IVM + 10?9, IVC + 10?9, IVM /IVC + 10?9). In Experiment 1, maturated oocytes from Control and IVM + 10?9 treatments showed increased glutathione content, mitochondrial membrane potential and percentage of Grade I blastocysts (40.6% and 43%, respectively). In Experiment 2, an increase in the percentage of Grade I blastocysts was detected in IVC + 10?7 (43.5%; 56.7%) and IVC + 10?9 (47.4%; 57.4%). Moreover, a lower number and percentage of apoptotic cells in blastocysts were observed in the IVC + 10?9 group compared to Control (3.8 ± 0.6; 3.6% versus 6.1 ± 0.6; 5.3%). In Experiment 3, the IVC + 10?9 treatment increased percentage of Grade I blastocysts with a lower number of apoptotic cells compared to IVM /IVC + 10?9 group (52.6%; 3.0 ± 0.5 versus 46.0%; 5.4 ± 1.0). The IVC + 10?9 treatment also had a higher mRNA expression of antioxidant gene (SOD 2) compared to the Control, as well as the heat shock protein (HSPB 1) compared to the IVM + 10?9. Reactive oxygen species production was greater in the IVM /IVC + 10?9 treatment group. In conclusion, the 10?9 M concentration of melatonin and the in vitro production phase in which it is used directly affected embryonic development and quality. 相似文献
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PE Bennemann GN Diehl E Milbradt RM Vidor HCC Fries I Wentz ML Bernardi FP Bortolozzo 《Reproduction in domestic animals》2005,40(6):507-510
This study evaluated the reproductive performance of gilts inseminated at three intervals before ovulation (0-12, 13-23, 24-30 h) with sperm doses (SD) stored for 0-48 and 96-120 h. A total of 218 PIC Camborough 22 gilts were inseminated once with SD of 1.5 x 10(9) sperms. Pregnant gilts (n = 166) were slaughtered 30.8 +/- 3.7 days after artificial insemination. The number of corpora lutea (CL) and total embryos (TE) was counted. Pregnancy rates (PR) were analysed by chi-square test. TE and embryonic survival (ES), obtained as the ratio between viable embryos and CL, were analysed by GLM procedure (SAS) and mean values were compared by Tukey's test. Pregnancy rate was similar among artificial insemination-ovulation (AIOV) intervals when semen was stored for 0-48 h. However, the lowest PR was observed in the 24-30 h AIOV interval with storage time (ST) of 96-120 h (p < 0.05). There was a significant effect of the interaction between ST and AIOV (p < 0.05) on TE and ES variables. Total embryos and ES did not differ (p > 0.05) among AIOV intervals in ST of 0-48 h. However, gilts inseminated at 24-30 h AIOV interval with ST of 96-120 h showed a reduction of 6.7 embryos (p < 0.05) compared with gilts in the same interval inseminated with semen stored for 0-48 h. ES for the 24-30 h AIOV interval and ST of 96-120 h was lower than that observed in the other groups (p < 0.05). 相似文献
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Thuring CM Crowe MA McAllister H Earley B Roche JF Sweeney T 《The Veterinary record》2002,150(4):97-102
Tissue samples were collected postmortem from 126 sheep at five lymphoreticular sites by different techniques. The three most successful combinations of sites and techniques were: the third eyelids, using a forceps and scissors, which provided a mean (se) of 5.32 (0.70) lymphoid follicles per 5 microm tissue section, a mandibular lymph node, using a Biopty gun, which gave 1.19 (0.26) lymphoid follicles per 5 microm tissue section, and tonsil, using a biopsy forceps, which gave 1.14 (0.27) lymphoid follicles per 5 microm tissue section. These three techniques were repeated once a month for five months on five sheep under general anaesthesia, and their clinical effects were compared with five control sheep which were restrained and anaesthetised in the same way but from which no biopsies were taken. Most lymphoid follicles (3.47 [0.58] per 5 pm tissue section) were obtained by using the third eyelid biopsy technique. There were no clinical side effects associated with the biopsy procedure. There were increases in the plasma concentration of cortisol in all the animals, suggesting that the restraint and anaesthesia were more stressful than the biopsy procedure. 相似文献
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