Superovulation of donor cows, embryo transfer, and estrus synchronization of recipients are widely used technologies in the purebred cattle industry. Progress continues to be made to achieve efficient and economic use of these technologies. The first retrospective study was conducted to compare embryo production between a stimulation protocol using only Folltropin as the gonadotropin, and a stimulation protocol using Folltropin and Pluset. Beefmaster donor cows (n=12) were stimulated using both protocols over two stimulated cycles, one protocol each cycle. Both protocols used the same synchronization protocol with only the gonadatropin injections differing. The control protocol (Folltropin protocol) consisted of seven Folltropin injections over the course of 3.5 days. The treatment protocol (Folltropin + Pluset protocol) consisted of four Folltropin injections followed by three Pluset injections over the course of 3.5 days. The mean numbers of viable embryos did not differ between treatments (P>0.01) and were 9.33 and 6.58 for the control and treatment protocols, respectively. The proportion of viable embryos to total ova for each protocol was 0.49 and 0.48 for the control and treatment protocols, respectively (P > 0.10). No significant difference on embryo production was observed between the control and treatment protocols. The second retrospective study was performed to compare pregnancy rates after embryo transfer between Beefmaster recipients who received eCG during synchronization and recipients who did not receive eCG during synchronization. Due to the conditions of this study, statistical analysis could not be performed. Pregnancy rates are reported, but they are not statistically significant. Recipients in the control group (n=332) were synchronized with a protocol using a CIDR insert for seven days, a progesterone estradiol injection at the time of CIDR insertion, a prostaglandin (PG) injection at CIDR removal, and an estradiol injection the day after CIDR removal. Recipients in the treatment group (n=142) were synchronized using the same synchronization protocol as the control group, except eCG was administered five days after CIDR insertion. Pregnancy rates were 44.88 and 38.73 for the control and treatment groups, respectively. The addition of eCG to the synchronization protocol did not appear to be either beneficial or detrimental to pregnancy rate under the conditions of this study. In summary, the addition of Pluset to the stimulation protocol for donors was not detrimental to embryo production. The estrus synchronization protocol with eCG for recipients did not appear to be beneficial; however, a controlled studies are still warranted to further investigate the potential effects of recipient age, parity, body condition score, or breed effect on response to eCG.

A series of experiments were designed to study the effects of a purified equine pituitary extract product containing a high FSH to LH ratio (eFSH) on superovulation and reproductive performance in mares. A significance level of P < 0.05 was used for the data analyses.<p> The treatment protocol included twice daily administration of 12.5 mg eFSH beginning at a follicular diameter of ¡Ý20 or 25 mm. The treatment was stopped when a preovulatory-sized follicle was detected (¡Ý35mm), and subsequently human chorionic gonadotropin (hCG) was administered to induce ovulation(s). The eFSH treatment significantly stimulated the ovaries of cycling and vernal transitional mares. This resulted in the development of multiple preovulatory-sized follicles, increased the number of ovulations, and enhanced donor embryo recovery rates. In mares which ovulated, approximately 70% of embryo recovery attempts resulted in the recovery of ¡Ý1 embryo. However, incidences of ovulation failure and non-ovulatory follicles were significantly higher compared to control mares. Furthermore, there were significant variations in the superovulatory response to eFSH among cycling and vernal transitional mares in the same study, and among different studies, in terms of number of ovulations, number of embryos and embryo per ovulation rates.<p> Administration of eFSH significantly modified reproductive tract variables (tone and edema) and serum concentrations of progesterone (P4) and estradiol-17¦Â (E2) on the days that oocyte maturation, fertilization, and early embryonic development were expected to occur. The administration of eFSH was also significantly associated with lower quality scores in a proportion of embryos recovered, and lower than expected pregnancy rates in recipients which received an embryo recovered from eFSH-treated cycling donor mares as compared to embryos from non-stimulated control mares. Moreover, eFSH treatment did not significantly increase pregnancy rate per estrous cycle in mares intended to carry their own pregnancy; however, the incidence of twin pregnancy tended to increase.<p> The effects of estrus synchronization regimens employed prior to eFSH treatment initiation were examined in cycling mares. A progesterone and estradiol regimen (P&E) was significantly more efficient than PGF2¦Á administration in diestrus for ovulation synchrony among eFSH-treated mares, with ¡Ý80% of mares ovulating within a 3 day period. The superovulatory outcomes (proportion of mares that ovulated, number of ovulations and embryo recovery), however, were significantly lower than those obtained with PGF2¦Á administration.<p> In vernal transitional mares, eFSH treatment resulted in a significantly higher number of preovulatory-sized follicles and a greater number of ovulations, compared to vernal transitional mares treated with deslorelin or porcine-FSH, or as compared to control mares. Most transitional mares (73% to 100%) ovulated after a mean of 5 days of eFSH treatment. These ovulations resulted in pregnancies and/or successful embryo recoveries. Following eFSH treatment in vernal transition, the first inter-ovulatory interval of the breeding season was significantly prolonged (>21 d) in about half of the mares.<p> In summary, eFSH treatment significantly stimulated follicular growth and multiple ovulations in cycling mares and in vernal transitional mares. The treatment significantly increased reproductive efficiency of cycling mares in terms of embryo recovery rates, and in vernal transitional mares in terms of establishing pregnancies or recovering embryos early in the breeding season. However, the eFSH treatment significantly altered the hormonal environment (E2 and P4), and was associated with modifications in follicular growth, ovulation, and embryo parameters. These aspects should be considered in the development of superovulation protocols for mares in future studies.

A series of experiments were designed to study the effects of a purified equine pituitary extract product containing a high FSH to LH ratio (eFSH) on superovulation and reproductive performance in mares. A significance level of P < 0.05 was used for the data analyses.<p> The treatment protocol included twice daily administration of 12.5 mg eFSH beginning at a follicular diameter of ¡Ý20 or 25 mm. The treatment was stopped when a preovulatory-sized follicle was detected (¡Ý35mm), and subsequently human chorionic gonadotropin (hCG) was administered to induce ovulation(s). The eFSH treatment significantly stimulated the ovaries of cycling and vernal transitional mares. This resulted in the development of multiple preovulatory-sized follicles, increased the number of ovulations, and enhanced donor embryo recovery rates. In mares which ovulated, approximately 70% of embryo recovery attempts resulted in the recovery of ¡Ý1 embryo. However, incidences of ovulation failure and non-ovulatory follicles were significantly higher compared to control mares. Furthermore, there were significant variations in the superovulatory response to eFSH among cycling and vernal transitional mares in the same study, and among different studies, in terms of number of ovulations, number of embryos and embryo per ovulation rates.<p> Administration of eFSH significantly modified reproductive tract variables (tone and edema) and serum concentrations of progesterone (P4) and estradiol-17¦Â (E2) on the days that oocyte maturation, fertilization, and early embryonic development were expected to occur. The administration of eFSH was also significantly associated with lower quality scores in a proportion of embryos recovered, and lower than expected pregnancy rates in recipients which received an embryo recovered from eFSH-treated cycling donor mares as compared to embryos from non-stimulated control mares. Moreover, eFSH treatment did not significantly increase pregnancy rate per estrous cycle in mares intended to carry their own pregnancy; however, the incidence of twin pregnancy tended to increase.<p> The effects of estrus synchronization regimens employed prior to eFSH treatment initiation were examined in cycling mares. A progesterone and estradiol regimen (P&E) was significantly more efficient than PGF2¦Á administration in diestrus for ovulation synchrony among eFSH-treated mares, with ¡Ý80% of mares ovulating within a 3 day period. The superovulatory outcomes (proportion of mares that ovulated, number of ovulations and embryo recovery), however, were significantly lower than those obtained with PGF2¦Á administration.<p> In vernal transitional mares, eFSH treatment resulted in a significantly higher number of preovulatory-sized follicles and a greater number of ovulations, compared to vernal transitional mares treated with deslorelin or porcine-FSH, or as compared to control mares. Most transitional mares (73% to 100%) ovulated after a mean of 5 days of eFSH treatment. These ovulations resulted in pregnancies and/or successful embryo recoveries. Following eFSH treatment in vernal transition, the first inter-ovulatory interval of the breeding season was significantly prolonged (>21 d) in about half of the mares.<p> In summary, eFSH treatment significantly stimulated follicular growth and multiple ovulations in cycling mares and in vernal transitional mares. The treatment significantly increased reproductive efficiency of cycling mares in terms of embryo recovery rates, and in vernal transitional mares in terms of establishing pregnancies or recovering embryos early in the breeding season. However, the eFSH treatment significantly altered the hormonal environment (E2 and P4), and was associated with modifications in follicular growth, ovulation, and embryo parameters. These aspects should be considered in the development of superovulation protocols for mares in future studies.

Tierärztl. Hochsch., Diss., 2004--Hannover.

Made available in DSpace on 2014-06-11T19:29:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-06-30Bitstream added on 2014-06-13T19:38:28Z : No. of bitstreams: 1 ignacio_fs_me_botfmvz.pdf: 358674 bytes, checksum: 05dc848a48059e14942a8e5507c2b22b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O presente estudo tem como objetivo verificar a resposta ovulatória e recuperação embrionária em éguas após o tratamento com FSHp (Folltropin-V®) em diferentes momentos, com diferentes doses e na raça BH. O crescimento folicular foi acompanhado diariamente e os tratamentos (i.m. a cada 12h) foram mantidos até que o maior(es) folículo(s) atingiu 32mm, a indução da ovulação (2500 UI de hCG i.v.) foi realizada quando o maior(es) folículo(s) atingiu 35mm e a colheita de embriões no D8. No experimento 1, a dose de 25mg de FSHp foi testada em 28 éguas para determinação do melhor momento após aspiração folicular: 13mm (n=7, salina, controle), 13mm (n=7, FSHp-F13) e 20mm (n=7, FSHp-F20); ou em um dia determinado do ciclo: D6 (n=7, FSHp- D6). No experimento 2, a dose de 50mg de FSHp foi testada em 17 éguas quando o maior folículo atingiu 13mm (n=7, FSHp-13) e comparada ao grupo controle (n=10). No experimento 3, em 26 éguas BH inciou-se os seguintes tratamentos no D6: salina (n=7, controle), 25mg de FSHp (n=7, 25FSHp-D6), 12,5mg de EPE (n=7, EPE-D6) e 50 mg de FSHp (n=5, 50FSHp-D6). Usou-se a análise de variância de perfil, seguida do método de Tukey e para os dados de embriões/ovulação foi realizado o teste exato de Fisher (5% de significância). Os tratamentos com 25mg ou 50mg não promoveram aumento significativo no número de ovulações e de embriões recuperados, mas promoveu aumento no diâmetro máximo atingido por F3. O início do tratamento quando o maior folículo da onda induzida atingiu 20mm reduziu o tempo de tratamento. Conclui-se que os tratamentos com FSHp não promoveram resposta satisfatória e que o início do tratamento próximo ao desvio permitiu redução no tempo de tratamento. / The present study aims to verify the ovulatory response and embrionary recover in mares treated at different moments with pFSH (Folltropin-V®), with different doses and in BH breeding mares. The follicular growth was daily accompanied and treatments (i.m. BID) were kept until major follicles reached 32mm, ovulation induction (2500 UI of hCH i.v.) was done when major follicles reached 35mm and embryo collection at D8. In experiment 1, 25mg of pFSH was tested in 28 mares for determination of the best moment for start of treatment after follicle ablation: 13mm (n=7, saline, control), 13mm (n=7, FSHp-F13) e 20mm (n=7, FSHp-F20); or in a previously determined cycle day: D6 (n=7, FSHp-D6). In experiment 2, 50mg of pFSH was tested in 17 mares when the largest follicle achieved 13mm (n=7, FSHp-13) and compared to a control grupo (n=10). In experiment 3, in 26 BH mares was initiated the following treatments beginning at D6: saline (n=7, control), 25mg of pFSH (n=7, 25FSHp-D6), 12,5mg of EPE (n=7, EPE-D6) e 50 mg of pFSH (n=5, 50FSHp-D6). For statistical analysis, Profile analysis followed by Tuckey method and, for embryo/ovulation, Fisher test were used (significance at 5%). Treatments with 25mg or 50mg did not promote a significative increase on ovulations and embryo recover, but increased maximum diameter of F3. The start of treatment when the largest follicle of an induced follicular wave achieved 20mm reduced time of treatment. It is concluded that pFSH treatment did not promote a satisfactory response and that beginning of treatment close to deviation allowed the reduction of treatment time.

Made available in DSpace on 2014-06-11T19:29:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-12Bitstream added on 2014-06-13T19:38:34Z : No. of bitstreams: 1 machado_ms_dr_botfmvz.pdf: 753288 bytes, checksum: 187c0d8cf0a2a6512626ff3476eafd08 (MD5) / Universidade Estadual Paulista (UNESP) / Respostas superovulatórias satisfatórias têm sido reportadas em éguas com o uso do Extrato de Pituitária Eqüina (EPE) e FSH purificado eqüino (eFSH), contudo as taxas de recuperação embrionária permanecem inconsistentes. O objetivo deste estudo foi avaliar as concentrações plasmáticas de estradiol, inibina, FSH e LH em éguas superovuladas com eFSH e EPE (em doses constantes ou decrescentes): antes, durante e imediatamente após o término da administração hormonal. Foram utilizadas seis éguas as quais foram submetidas aos seguintes tratamentos: Grupo I (GI) recebeu 25mg de EPE intramuscular (I.M.), Grupo II (GII) foram tratadas com EPE (I.M.) em doses decrescentes. No Grupo IIl (GIII), o EPE foi substituído por 12,5mg de eFSH (I.M.). O Grupo IV (GIV) foi utilizado como controle. Sangue foi coletado diariamente para avaliar as concentrações hormonais por radioimunoensaio. As coletas foram iniciadas dois dias antes da primeira aplicação medicamentosa, encerrando 48horas após a última ovulação do estro. As diferenças nos níveis plasmáticos hormonais foram comparadas utilizando-se o ANOVA, sendo considerada diferença estatística quando P0,05. O número médio de ovulações foi de 3,3; 4,8; 5,0 e 1,0 nos grupos 1 a 4, respectivamente, tendo sido maior (P<0,05) em todos os grupos superovulados em relação ao controle. As concentrações de estrógeno, inibina, FSH e LH não diferiram entre os grupos durante o período 1. No período 2, os valores de estradiol foram maiores (P<0,05) em éguas sob tratamento superovulatório com eFSH (GIII) 29,52pg/ml, os grupos I e II, apresentaram valores intermediários (GI: 16,75pg/ml, GII: 16,26pg/ml) e o GIV (7,78pg/ml) menor estatisticamente aos demais. Foi verificada uma correlação altamente positiva (R=0,615; P=0,01) entre os valores de estradiol e inibina, os quais, durante os tratamentos, foram maiores (P<0,05)... / Satisfactory superovulatory responses have been reported in mares with the use of equine pituitary extract (EPE) and purified equine FSH (eFSH), however embryo recovery rates are still inconsistent. Recent studies demonstrated that the superovulatory treatment disturbs oocyte maturation and transport. The main objective of the present study was to evaluate the plasmatic concentrations of estradiol, inhibin, FSH and LH in super ovulated mares treated with eFSH and EPE (with constant or decreasing doses): Six mares were used in a crossover experiment in four different groups: Group I mares received 25mg of EPE every twelve hours, Group II received EPE in decreasing doses and Group IlI mares received 12.5mg of eFSH (IM). Group IV served as control. Embryo flushes were performed 8 days pos ovulation. Blood was collected daily to evaluate hormonal concentrations through radioimuneassay, starting two days before the first administration, until 48 hours post-ovulation. Mean and daily hormonal concentrations of estradiol, inhibin, FSH and LH were evaluated. Hormonal concentrations were submitted to statistical analysis using ANOVA. Significance levels were set as P<0.05. Mean number of ovulations was 3.3; 4.8; 5.0 and 1.0 in groups 1 to 4, respectively, being higher (P<0.05) in all super ovulated groups, when compared to control. Concentrations of estrogen, inhibin, FSH and LH did not differ between groups during the first period. In period 2, estradiol levels were higher (P<0.05) in mares with superovulatory treatment eFSH (GIII) 29.52pg/ml, the groups GI and GII (GI: 16.75pg/ml, GII: 16.26pg/ml) values intermediary, and GIV (7.78pg/ml) levels lower. A positive correlation between estradiol levels and number of follicles ≥30mm (R=0.917; P<0.05), recovered embryos (R=0.945; P<0.05) and ovulations (R=0.75; P<0.05) was identified in super ovulated mares. A positive correlation (R=0.615; P=0.01) between estradiol and inhibin concentrations.

To identify factors important to the efficiency of artificial insemination in cattle, four studies were conducted. In the first study, the addition of cream to the inseminate was used in an attempt to increase accessory sperm number. On d 6 after insemination, 60 embryos were evaluated. The addition of cream to the inseminate had no effect on accessory sperm number. In the second study, cryopreserved semen of a marked bull (spermatozoa exhibiting a semi-flattened anterior head) was matched with semen from an unmarked bull (conventional sperm head shape) to determine competitively the effect of a deep uterine insemination on accessory sperm number. Forty embryos were recovered 6 d after insemination and the ratio of accessory sperm observed was different: 62:38 for unmarked semen in the uterine body and marked semen in the uterine horn, and 72:28 for unmarked semen in the uterine horn and marked semen in the uterine body (P < .05). In the third study, superovulated cows were utilized to determine the effect of artificial insemination time on fertilization status and accessory sperm number. Cows were inseminated once at 0 h (n=10), 12 h (n=10), or 24 h (n=10) after the first standing event. On d 6 after insemination, 529 embryos(ova) were recovered. Fertilization rates were 29% (0 h); 60% (12 h); and 81% (24 h)(P < .01). Percentages of embryos with accessory sperm were: 5 (0 h); 8 (12 h); and 41(24 h) (P < .01). In the fourth study, three experiments utilizing superovulated cows were conducted to provide a basis for distinguishing unfertilized ova from very early embryonic death. In Exp. 1, recovered d 6 unfertilized ova were classified morphologically as either: 1) typical, 2) satellite, or 3) fragmented. In Exp. 2, recovered d 6 unfertilized ova from the third study were classified morphologically, and typical ova were fixed. In Exp. 3, ultrastructural features of preovulatory, tubal-stage, and typical d 6 unfertilized ova were investigated. Preovulatory ova revealed normal ultrastructure; tubal-stage ova exhibited evidence of degeneration; typical d 6 ova were degenerated and contained no discernable organelles. The first three studies support the use of accessory sperm evaluation as an alternative measure of fertility. The final study provides a basis from which future embryologists may distinguish fertilization failure from very early embryonic death. / Ph. D.

High levels of dietary protein may be detrimental to reproductive performance in cattle. The objective of Exp. 1 was to determine the effects of differences in dietary protein on the production and quality of bovine embryos collected from superovulated donors. Angus cows were randomly assigned to receive one of three experimental diets: a daily ration of 5.7 kg poultry litter, 2.0 kg hay, 3.1 kg corn, and 0.5 kg peanut hulls (LITTER; n = 15); a daily ration of 6.2 kg peanut hulls, 2.2 kg soybean meal, 2.0 kg hay, 0.5 kg corn, and 0.4 kg dicalcium phosphate (SBM; n = 15); or a daily ration of 6.2 kg peanut hulls, 2.0 kg hay, and 3.1 kg corn (CON; n = 19). Diets differed in the amount of total, soluble and degradable protein, but were comparable in energy. After 30 d on the diets, all cows were treated to induce superovulation (28.8 mg FSH/cow, Folltropin) and synchronize estrus. After the detection of estrus each cow was inseminated with semen from one of four Holstein bulls. Embryos were collected 7 d after estrus and evaluated for quality (according to the International Embryo Transfer Society (IETS) standards) and stage of development. Prior to treatment to induce superovulation, blood samples were collected 6 h after feeding. Samples were analyzed to assess dietary effects on plasma urea nitrogen (PUN). Mean levels of PUN were higher (P < 0.01) in cows fed the LITTER or SBM diet (16.3 mg/dL, LITTER; 21.8 mg/dL, SBM; 9.7 mg/dL, CON) than in cows fed the CON diet. Additionally, concentration of PUN was higher in cows fed SBM than in those fed LITTER (P < 0.01). An average of 9.2 transferable embryos (Grade 1, 2 and 3) was collected from each cow and there were no significant differences in the number of transferable embryos collected among groups (9.2, LITTER; 9.3, SBM; 9.1, CON). The number of degenerate embryos or unfertilized ova did not differ among dietary groups. High-protein diets elevated PUN, but did not affect the number or quality of embryos collected from superovulated donors. Cryopreservation of bovine embryos is an important aspect of a successful embryo transfer program. The objective of Exp. 2 was to evaluate the post-thaw viability of bovine embryos collected in Exp. 1 in an in vitro culture system after the embryos had been held at room temperature or refrigerated for 2 to 12 h prior to freezing. Upon embryo recovery, each embryo was randomly assigned to be placed in holding media for 2, 6 or 12 h prior to freezing. During this interval, one-half of the embryos were maintained in a refrigerated environment (5 °C), while the remaining half of the embryos were held at room temperature (20.5 to 22 °C) until freezing. Immediately prior to freezing, embryos were removed from the holding media, transferred to a well containing ethylene glycol (10%) in ovum culture media and loaded individually into a 0.25-mL plastic straw. Straws were then placed in a freezer unit (-6 °C) and seeded to induce ice crystal formation through all columns of the straw. The temperature of the freezer was then decreased 0.6 °C/min to -32 °C, and straws were loaded into canes and plunged into a liquid nitrogen tank (-196 °C). After storage, each straw was exposed to a 5-s air thaw and placed in a water bath at 35 °C for 20 s. Each embryo was then washed to remove excess ethylene glycol prior to in vitro culture. Embryos were individually cultured in Ham's F-10 media supplemented with 4% fetal bovine serum for 72 h. Embryos were evaluated at 24 h intervals throughout the culture period and assigned a stage of development and quality grade score (according to IETS standards). The percentage of embryos that developed to the expanded blastocyst stage and hatched from the zona pellucida was greater for embryos held 2 or 6 h prior to freezing (P < 0.05) than for embryos held for 12 h after collection before being frozen (62.9, 52.0 and 31.1%, respectively). The percentage of embryos that degenerated during in vitro culture was lower for embryos held 2 or 6 h prior to freezing (20.4 and 26.6%; P < 0.05) than for embryos held for 12 h before freezing (50.8%). Furthermore, embryo quality grade was more desirable for embryos held for 2 or 6 h (1.5 and 1.7; P < 0.05) than for those held for 12 h before freezing (2.1). The semen used to inseminate donors and the diet fed to donors for 4 wk prior to embryo collection did not influence the proportion of embryos that hatched or degenerated during the 72 h of in vitro culture. Additionally, holding embryos in a refrigerated environment from the time of collection until freezing did not enhance embryonic development during post-thaw culture. Thus, embryonic viability may be impaired when embryos are held longer than 6 h following embryo recovery before being frozen; however, the storage temperature during the interval from collection to freezing does not influence embryonic development post-thaw. / Master of Science

Orientador: Cezinande de Meira / Banca: Sony Dimas Bicudo / Banca: Cássia Maria Barroso Orlandi / Resumo: O presente estudo visou avaliar a resposta ovariana e a taxa de recuperação embrionária em éguas tratadas com EPE nas doses de 6, 8 e 12,5 mg sendo o tratamento iniciado após a aplicação de prostaglandina F2 no oitavo ou sexto dia após a ovulação com a finalidade de reduzir o tempo e custo do tratamento. Foram realizados dois experimentos, para o experimento 1, 40 ciclos estrais de éguas Mangalarga Marchador, entre cinco e 24 anos, e para o segundo experimento 30 ciclos estrais de éguas mestiças entre quatro e 12 anos de idade, foram estudados. Foi aplicada 7,5 mg i.m.de prostaglandina F2 (Dinoprost Trometamina) no oitavo (experimento 1) ou sexto (experimento 2) dia após a ovulação. Nesse momento as éguas foram distribuídas aleatoriamente em cinco grupos para o experimento 1: (n=8 ciclos estrais/grupo): Grupo F20-23mm 6mg e F20-23mm 8mg receberam 6 e 8mg, respectivamente, de EPE por via i.m. a cada 12 horas, a partir da detecção de folículo(s) entre 20-23mm de diâmetro. Nos Grupos D8 - 6mg e D8 - 8mg foi aplicado 6 ou 8 mg de EPE, respectivamente, a cada 12 horas por via i.m. a partir do D8 (concomitante a PGF2 ). No Grupo F20-23mm Salina (Controle): as éguas receberam solução salina respeitando os mesmos intervalos que os grupos tratados com EPE a partir da detecção de folículo(s) entre 20-23mm de diâmetro. No experimento 2, a metodologia foi similiar ao experimento 1, contudo, as éguas receberam 12,5 mg de EPE, e o tratamento foi iniciado no sexto dia após a ovulação para o Grupo D6-12,5 mg (n=9), ou quando detectou-se folículo(s) entre 20-23mm, Grupo F20-23mm 12,5 mg (n=10) e F20-23mm Salina (Controle, n=10). Em todos os grupos (Exp. 1 e 2) o tratamento (EPE ou salina) foi mantido até 12 horas anterior a detecção de folículo(s) com diâmetro 35 mm, nesse momento a ovulação foi induzida com única dose de 2500 U.I. de hCG, i.v. (Vetecor®)... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present study aimed to evaluate the ovarian response and embrionary recovery in mares treated with doses of 6, 8 and 12.5 mg of EPE. The treatment was started after application of prostaglandin F2 for reduce the period and cost of treatment. Two experiments were conducted, for the experiment one, 40 estrous cycles of Mangalarga Marchador mares and ranged in age from 5 to 24 yrs, and for the second experiment 30 estrous cycles of crossbreed mares ranged in age from four to 12 yrs was used. In the eighth (experiment 1) or sixth (experiment 2) after ovulation was applied 7.5 mg i.m. of prostaglandin F2 (Dinoprost Trometamina). In this moment, all mares in experiment 1 was randomly assigned to treatment and control groups as follows: Groups 1 and 2 (n=8 cycles/group) received 6 mg of EPE, i.m. twice daily, beginning when largest follicle (s) was (were) 20-23 mm (Group F20-23mm 6mg) or regardless of follicle size on Day 8 (Group D8 - 6 mg); Groups 3 and 4 (n=8 cycles/group), received 8 mg of EPE, i.m. twice daily, beginning when largest follicle was 20-23 mm (Group F20-23 mm 8 mg) or regardless of follicle size on Day 8 (Group D8 - 8mg); Group F20-23mm Saline (Control, n=8 cycles) received saline, i.m. beginning when largest follicle (s) was (were) 20-23 mm in the same range of groups treated with EPE. In the second experiment was used the same methodology of the experiment 1, however, the mares received 12.5mg of EPE, and the treatment began in the sixth day after ovulation for the Group D6- 12.5mg (n=9), or when the largest follicle (s) was (were) 20-23 mm, Group F20-23mm 12,5 mg (n=10) e F20-23mm Saline (Control, n=10). Treatments with EPE or saline continued until 12 hours before detection of follicle (s) reached 35 mm, at which time a single dose of hCG (2500 U.I., i.v., Vetecor®) was given. Groups were compared using ANOVA and mean differences among groups were... (Complete abstract click electronic access below) / Mestre

Apesar de inúmeros estudos desenvolvidos no Brasil e no mundo, a utilização das biotecnologias de superovulação (SOV) e transferência de embriões (TE) em bubalinos ainda apresenta resultados inconsistentes, associados à principalmente à baixa taxa de recuperação de embriões. Dessa forma, o objetivo do presente estudo foi avaliar o efeito da utilização de dispositivo de P4 (para promover diminuição da contratilidade do trato genital, Capitulo 1) ou da administração de PGF2&#945; (para promover aumento da atividade da fímbria e da frequência do batimento ciliar, Capítulo 2) durante o período periovulatório na captação dos oócitos pelas fímbrias e no aumento da produção de embriões em búfalas superovuladas. No Experimento 1 (Capítulo 1), doadoras bubalinas foram homogeneamente divididas em dois grupos: controle (G-C; n=8) e tratamento com progesterona (P4) durante o período periovulatório (G-P4; n=8). A emergência da onda de crescimento folicular foi sincronizada com um dispositivo intravaginal de P4 e a administração de 2 mg i.m. de benzoato de em dia aleatório do ciclo estral (Dia 0; D0). A partir do D4, todas as búfalas receberam 200 mg i.m. de FSH duas vezes ao dia, em 8 doses decrescentes. Foram administrados 530&micro;g i.m. de PGF2&#945; no D6 e no D7. A P4 foi removida do G-C no D7 e do G-P4 no D10. No D8, todas as búfalas receberam 25 mg i.m. de pLH. As inseminações foram realizadas 12 e 24 h após o tratamento com pLH. Foram realizadas colheitas de sangue a cada 12h do D7 ao D11 para posterior dosagem de progesterona. As estruturas embrionárias (oócitos/embriões) foram coletadas pelo método não cirúrgico de lavagem uterina seis dias após a segunda IA (D14). Avaliações ultrassonográficas dos ovários foram realizadas no D8 e no D14 para aferir respectivamente as respostas superestimulatória e superovulatória. As variáveis foram analisadas pelo procedimento GLIMMIX do SAS®. As búfalas do G-P4 apresentaram menor taxa de ovulação (13,5±4,9 vs. 71,5±16,1%; P=0,002) e, consequentemente, maior taxa de folículos &ge; 8 mm (87,8±10,6 vs. 34,3±9,8 %; P=0,06) e menor número de CLs no D14 (1,1±0,3 vs. 8,0±2,8; P=0,04) que as búfalas do G-C. O número de estruturas embrionárias (1,9±0,7 vs. 0,0±0,0; P=0,03), de embriões transferíveis (1,6±0,7 vs. 0,0±0,0; P=0,04) e congeláveis (1,6±0,7 vs. 0,0±0,0; P=0,04) foram inferiores para o G-P4. A concentração sérica de progesterona foi maior nos animais do G-P4 (1,87±0,13) que nos do G-C (0,48±0,10; P<0,0001). No Experimento 1 (Capítulo 2), as doadoras foram divididas aleatoriamente em 2 grupos: controle (G-C; n=22) e tratamento com prostaglandina F2&#945; durante o período periovulatório (G-PGF; n=22). Os animais do G-C foram submetidos ao protocolo de superovulação descrito no capítulo 1. No G-PGF todas as búfalas receberam protocolo de superovulação semelhante ao G-C e, adicionalmente, receberam quatro doses de PGF2&#945; (0,53 mg i.m. de cloprostenol sódico) do D8 ao D10 com intervalo de 12h. Foi verificado maior número de estruturas embrionárias recuperadas em búfalas superovuladas tratadas com PGF2&#945; durante o período periovulatório (G-PGF=3,5±0,6) comparado ao grupo controle (G-C=2,3±0,5; P=0,02). Além disso, houve aumento no número de embriões transferíveis (G-PGF=2,7±0,6 vs. G-C=1,8±0,5; P=0,05). No Experimento 2 (Capítulo 2), os animais foram divididos aleatoriamente em três grupos experimentais: Grupo Controle (GC; n=22), Grupo PGF injetável (G-PGF-INJ; n=22) e Grupo PGF Bomba Osmótica (G-PGF-BO; n=22). Os animais pertencentes aos grupos: G-C e G-PGF-INJ foram submetidos aos mesmos protocolos descritos para seus grupos correspondentes no Experimento 1 (Capítulo 2). No GPGF- BO, todas as búfalas receberam protocolo de superovulação semelhante ao G-C e, adicionalmente, receberam a partir do D8 a inserção subcutânea de uma mini-bomba osmótica, contendo PGF2&#945; (2,12 mg de Cloprostenol sódico). A bomba osmótica retirada no D10. Não foram verificadas diferenças no número de estruturas totais recuperadas nas búfalas tratadas com PGF&#945; durante o período periovulatório (G-C=2,1±0,8 vs. G-PGF-INJ=2,1±0,6 vs. GPGF- BO=1,4±0,4; P=0,58). Os tratamentos no período periovulatório com dispositivo intravaginal de P4 (Capítulo 1) e com PGF2&#945; (Capítulo 2) não foram eficientes em aumentar a recuperação de estruturas embrionárias de búfalas superovuladas. / Despite numerous studies conducted in Brazil and world-wide, the use of superovulation (SOV) and embryo transfer (ET) biotechnologies in buffaloes still shows inconsistent results, particularly in terms of low embryos recovery rate. Thus, the aim of this study was to evaluate the use of a P4 device (to decrease contractility of the genital tract, Chapter 1) or PGF2&alpha; administration (to increase activity of the fimbriae and ciliary beat frequency, Chapter 2) during the periovulatory period in the uptake of oocytes by fimbriae and in the increase of embryo production in superovulated buffaloes. In Experiment 1 (Chapter 1), buffalo donors were homogeneously assigned into 2 groups: Control (C-G; n=8) and progesterone (P4) treatment during the periovulatory period (P4-G; n=8). Follicular growth wave emergence was synchronized with an intravaginal P4 device and the injection of 2 mg i.m. of estradiol benzoate at random stage of the estrous cycle (Day 0; D0). From D4 on, all buffaloes received 200 mg i.m. of FSH twice-daily, in 8 decreasing doses. A dose of PGF2&alpha; was given on D6 PM and on D7. The P4 was removed from the C-G on D7 and from the P4-G on D10. On D8, all buffaloes received 25 mg i.m. of pLH. Inseminations were done 12 and 24 h after the pLH treatment. Blood samples were collected every 12h from D7 to D11 for further progesterone assay. The embryonic structures (ova/embryos) were collected by nonsurgical uterine flush 6 days after the second timed AI (D14). Ovarian ultrasound examinations were performed on D8 and on D14 to verify respectively the superestimulation and the superovulatory response. Variables were analyzed by GLIMMIX procedure of SAS®. Buffaloes from P4-G showed lower ovulation rate (13.5±4.9 vs. 71.5±16.1%; P=0.002) and, consequently, higher follicles &ge; 8 mm rate (87.8±10.6 vs. 34.3±9.8 %; P=0.06) and lower number of CLs on D14 (1.1±0.3 vs. 8.0±2.8; P=0.04) than buffaloes from C-G. The total number of embryonic structures (1.9±0.7 vs. 0.0±0.0; P=0.03), transferable (1.6±0.7 vs. 0.0±0.0; P=0.04) and freezable embryos (1.6±0.7 vs. 0.0±0.0; P=0.04) were lower for P4-G. The serum progesterone concentration was greater for animals in P4-G (1.87±0.13) than in the C-G (0.48±0.10; P<0.0001). In Experiment 1 (Chapter 2), donors were randomly assigned into two groups: control (C-G; n=22) and prostaglandin F2&alpha; treatment during the periovulatory period (G-PGF; n=22). Animals from C-G were subjected to the superovulation protocol described on chapter 1. In G-PGF all buffaloes received similar superovulation protocol from the C-G and, additionally, received four doses of PGF2&alpha; (0.53 mg i.m. of sodic cloprostenol) from D8 to D10, 12h apart. A greater number of embryonic structures were recovered from superovulated buffaloes treated with PGF2&alpha; during the periovulatory period (PGF-G=3.5±0.6) compared to control group (C-G=2.3±0.5; P=0.02). Furthermore, increased number of transferable embryos were found in treated animals (PGF-G=2.7±0.6 vs. C-G=1.8±0.5; P=0.05). In Experiment 2 (Chapter 2), animals were randomly assigned into three experimental groups: Control group (CG; n=22), Injectable PGF group (INJ-PGF-G; n=22) and Osmotic pump PGF group (BO-PGF-G; n=22). The animals from C-G and INJ-PGF-G group were subjected to the same protocols described for their correspondent groups in Experiment 1 (Chapter 2). In BO-PGF-G, all buffaloes received the superovulation protocol similar to C-G and, additionally, received from D8, a subcutaneous insertion of a mini osmotic pump, containing PGF2&alpha; (2.12 mg de sodic cloprostenol). The osmotic pump was removed on D10. No differences were found on the total number of recovered structures in buffaloes treated with PGF2&alpha; during the periovulatory period (C-G=2.1±0.8 vs. INJ-PGF-G=2.1±0.6 vs. BO-PGF-G=1.4±0.4; P=0.58). Treatments on the peri- ovulatory period with intravaginal P4 device (Chapter 1) and PGF2&alpha; (Chapter 2) were not efficient in increasing the recovery of embryonic structures in superovulated buffalo.