Abstract An estrous-detection patch was used to determine the optimum timing for STAI and the necessity of GnRH at STAI on a 7-day CO-Synch+CIDR protocol. Crossbred beef cows (n=216) were stratified into the following treatment groups: CTRL=TAI (n=67) at 72 h post CIDR removal, or TRT=STAI (n=149) at 72 or 84 h post CIDR removal. All females received GnRH (100 mcg) plus a CIDR on d0, PGF2α, CIDR removal, and an Estrotect estrous-detector patch on d7. At 72 h post-CIDR removal, a patch score was assigned (PS1<50% removed; PS2>50% removed) to all females. Cows in the CTRL group were administered a second GnRH (100 mcg) at 72 h TAI. Cows in the TRT group with PS2 were not administered GnRH. At 84 h, the remaining TRT group cows were given a second PS; cows with PS1 received a GnRH (100 mcg), and cows with PS2 were not administered. Results: The TAI pregnancy rates were similar (P=0.81) between the CTRL (45.6%) and TRT (44.8%) groups. Pregnancy rates tended to be higher (P=0.07) for cows with PS2 (50.3%) than for those with PS1 (29.4%). However, by extending TAI to 84 h in unresponsive cows, 82.0% of TRT cows did not receive a second injection of GnRH at TAI. It was concluded that the estrous detector patches reduced the percentage of cows that required GnRH at TAI without compromising pregnancy rates. The estrous detector patches significantly reduced the number of cows that received a second GnRH injection at TAI.

Resumo Um adesivo de detecção de estro foi usado como ferramenta para determinar o momento ideal para a inseminação artificial em tempo dividido (STAI) e a necessidade de injeção de hormônio liberador de gonadotrofinas (GnRH) no 7º dia do protocolo CO-Sinc + CIDR sem comprometer as taxas de prenhez. As vacas eram cruzadas, multíparas e lactantes (Angus x Charolês, n=216) e foram estratificadas por idades (5,9 2.5 anos), BW (581 67kg), BCS (5,3 0,8; 1-9), intervalo entre partos (78,5 15,5 dias). O grupo de tratamento CTRL = IAT (n=67) foi inseminado após 72 h após a remoção do CIDR; já no grupo tratamento TRT= IATP (n=149) as vacas foram inseminadas 72 ou 84 h após a remoção do CIDR. Todas as fêmeas receberam GnRH (100 mcg I.M.), mais um CIDR (1,38 g de progesterone) no D0, no D7 foi realizado a retirada do CIDR, aplicação de PGF2α (25 mcg I.M.) e colocação do adesivo detector de cio. Após 72 h da remoção do CIDR, uma pontuação foi atribuída ao adesivo (OS1<50% removido; OS2> 50% removido) de todas as fêmeas. As vacas do grupo CTRL receberam a segunda injeção de GnRH (100 mcg I.M.) às 72 h na IAT. Vacas do grupo TRT com OS2 não receberam GnRH. Às 84 h as vacas restantes do grupo TRT receberam um segundo OS, aquelas com OS1 receberam GnRH (100 mcg I.M.) e as vacas com OS2 não receberam GnRH. Amostras de sangue para concentração de progesterona foram coletadas nos D-11 e D-0 para determinar o percentual de vacas ciclando. Os dados foram analisados utilizando-se o Proc Genmod, tendo o tratamento e o técnico de IA como efeitos fixos, o touro como efeito aleatório e o BW, BCS, idade e IBP como covariáveis. Resultados: as taxas de gravidez da IAT foram semelhantes (P= 0,81) entre os grupos CTRL (45,6%) e TRT (44,8%). As taxas de prenhez tenderam a ser maiores (P=0,07) para vacas com OS2 (50,3%) do que para aquelas com OS1 (29,4%). No entanto, ao estender a IAT para 84 horas em vacas não responsivas, 82,0% das vacas TRT não receberam uma segunda aplicação de GnRH na IAT. Concluiu-se que os adesivos detectores de estro reduziram a porcentagem de vacas que necessitaram de GnRH na IAT sem comprometer as taxas de prenhez. Os adesivos de detecção de estro reduziram significativamente o número de vacas que receberam uma segunda injeção de GnRH na IAT.

Resumo O objetivo do estudo foi verificar a eficiência e a ovulação após a administração de diferentes indutores para a sincronização da ovulação em vacas de corte. Cento e oito vacas não-lactantes foram distribuídas em grupo controle (GC; não tratadas; n=28); grupo benzoato de estradiol (BE) (GBE; n=28); grupo 17 beta-estradiol (17ßE) (G17ßE; n=28) e grupo deslorelina (DES) (GDES; n=24). No dia menos 11 (D-11) do protocolo, o GC recebeu cloprostenol e exame ultrassonográfico (US); ao D0, dispositivo de progesterona (P4) foi inserido mais BE; ao D7, cloprostenol foi aplicado; ao D9, a P4 foi removida e cloprostenol mais 400 UI de gonadotrofina coriônica equina (eCG) foi injetada. O GBE foi submetido a tratamento idêntico ao do GC, exceto ao D10, quando as vacas receberam BE. o G17ßE foi submetido ao mesmo protocolo usado no CG exceto pela administração de 17ßE ao D10. E, o GDES foi submetido ao mesmo tratamento que o CG, exceto ao D10, quando o grupo recebeu o acetato de DES. Doze horas após a administração de BE, 17ßE e DES, US ovarianos foram realizados a cada 6 horas. O diâmetro do folículo pré-ovulatório (FPO) medido antes da ovulação foi de 19,5; 14,7; 18,7 e 19,8 mm respectivamente para GC, GBE, G17ßE e GDES; e o intervalo de tempo entre a aplicação do indutor e ovulação foi 20,2; 18,9; 21;0 e 22,5 horas respectivamente. Em conclusão, todos os indutores da ovulação foram eficientes em promover a ovulação; os indutores acarretaram ovulação entre 18,9 e 22,5 horas; o BE promoveu a ovulação em menor espaço de tempo (P<0,05); 17ßE e DES demonstraram maior variação em aplicação/tempo de ovulação entre os grupos.

Abstract The aim of this study was to verify the efficiency and ovulation time after the administration of different inducers for synchronization of ovulation in beef cows. One hundred and eight non-lactating cows were distributed into the control group (CG; untreated; n=28), estradiol benzoate (EB) group (EBG; n=28); 17 beta-estradiol (17ßE) group (17ßEG; n=28), and deslorelin (DES) group (DESG; n=24). On day minus 11 (D-11) of the protocol, the CG underwent application of cloprostenol and ultrasound examination (US); on D0, progesterone (P4) was inserted plus EB; on D7, cloprostenol was applied; on D9, P4 was removed and cloprostenol plus 400 IU of equine chorionic gonadotropin (eCG) was injected. The EBG was subjected to treatment identical to that of the CG, except on D10, when the cows received EB. The 17ßE was subjected to the same protocol used in the CG except for the administration of 17ßE on D10. And, the DESG was subjected to the same treatment as the CG, except on D10, when the group received DES acetate. Twelve hours after the administration of EB, 17ßE and DES, ovarian US were performed every 6 hours. The preovulatory follicle (POF) diameters measured before ovulation were 19.5; 14.7; 18.7 and 19.8 mm respectively for CG, EBG, 17ßEG and DESG; and the time intervals between inducer application and ovulation were 20.2; 18.9; 21.0 and 22.5 hours respectively. In conclusion, all ovulation inducers were efficient in promoting ovulation; the inducers caused ovulation between 18.9 and 22.5 hours; EB promoted ovulation in a shorter time (P<0.05); 17ßE and DES showed greater variation in application/ovulation time between groups.

RESUMO: Os objetivos do estudo foram avaliar a correlação do sexo fetal com as concentrações plasmáticas de testosterona entre o 5° e o 8º mês de gestação na égua e verificar a aplicabilidade deste exame para a predição do sexo fetal. Amostras de sangue foram coletadas de 21 éguas, com intervalos de 30 dias, entre 150 e 240 dias de gestação. A testosterona plasmática foi determinada por radioimunoensaio e o sexo dos potros foi confirmado ao nascimento. Os valores de testosterona materna foram superiores nas éguas gestando fetos fêmeas aos cinco e oito meses (P< 0.05). Através da análise da curva ROC (receiver operating characteristic) foram determinados valores limites de 35,5 pg/mL e 40 pg/mL para o 5º e o 8° mês, respectivamente. Éguas com testosterona plasmática igual ou acima dos valores limites foram preditas como gestando fêmeas e éguas com testosterona plasmática abaixo dos valores limites foram preditas como gestando machos. Aos cinco meses, os valores preditivos para fetos machos e fêmeas foram 70% e 88,9%, respectivamente; as taxas de detecção foram 87,5% e 72,7% e a acurácia total do exame foi de 78,9%. Aos oito meses, os valores preditivos para fetos machos e fêmeas foram 80% e 90%, respectivamente; as taxas de detecção foram 88,9% e 81,8% e a acurácia total do exame foi de 85%. Conclui-se que houve correlação entre o sexo fetal e as concentrações de testosterona plasmática em éguas prenhes. A predição do sexo fetal baseada nas concentrações plasmáticas de testosterona materna pode ser realizada aos cinco e oito meses de gestação com 78,9% e 85% de acurácia, respectivamente.

ABSTRACT: The objectives of this study were to evaluate the correlation of fetal sex and plasma testosterone concentrations between the 5th and 8th months of pregnancy in mares and to verify the applicability of this test to predict fetal sex. Blood samples were collected from 21 mares at 30-day intervals of between 150 and 240 days of pregnancy. Plasma testosterone was determined by radioimmunoassay and the sex of the foals confirmed at birth. The levels of maternal testosterone were higher in mares carrying female fetuses at months 5 and 8 (P < 0.05). Limit values were determined by analyzing the receiver operating characteristic (ROC) estimates: 35.5 pg/mL and 40 pg/mL for the 5th and 8th month, respectively. For the mares with plasma testosterone values equal to or above the threshold, gestation of female foals was predicted, and for those with plasma testosterone below the threshold values pregnancy of male foals was predicted. In the 5th month, the predictive values for male and female fetuses were 70% and 88.9%, respectively; the detection rates were 87.5% and 72.7%, and the total accuracy of the examination was 78.9%. In the 8th month, the predictive values for male and female fetuses were 80% and 90%, respectively; the detection rates were 88.9% and 81.8%, and the total accuracy of the examination was 85%. It was concluded that there was a correlation between fetal sex and plasma testosterone concentrations in pregnant mares. Prediction of fetal sex based on plasma concentrations of maternal testosterone can be performed in months 5 and 8 with 78.9% and 85% accuracy, respectively.

RESUMO: A recuperação e preservação dos espermatozoides após a morte possibilita maior aproveitamento de animais geneticamente superiores. O objetivo deste trabalho foi avaliar o período máximo após a morte do carneiro para que os espermatozoides possam ser refrigerados em meio diluidor com ou sem plasma seminal. Foram utilizadas três amostras de espermatozoides colhidos em vagina artificial (AV) de 10 carneiros ou da cauda de quatro epidídimos provenientes dos mesmos carneiros no momento da morte (G0) e seis (G6), doze (G12), vinte e quatro (G24) e quarenta e oito (G48) horas após a morte. Após a recuperação os espermatozoides (em AV ou cauda do epidídimo) foram refrigerados à 5°C em dois tratamentos: meio controle (CM) ou meio controle acrescido de 20% de plasma seminal homólogo (SP) e avaliados até 72 horas após o início da refrigeração. As amostras do G48 apresentaram motilidade total (TM) e integridade de membrana plasmática no teste hiposmótico (HOST) menor (P<0,05) que os outros grupos avaliados em todos os momentos estudados. TM diminuiu (P<0,05) após 24 horas de refrigeração no sêmen colhido em AV, no G0 e G24 e a partir de 48 horas de refrigeração no G6 e G12. A TM, integridade de membrana no HOST e morfologia espermática não diferiram entre as amostras refrigeradas em CM ou SP. Contudo, é possível refrigerar espermatozoides epididimários até 24 horas post mortem, a refrigeração prolonga a viabilidade espermática até 48 horas após o início da refrigeração. A adição de 20% de plasma seminal ao meio diluidor não tem efeito sobre a longevidade espermática.

ABSTRACT: Preservation and use of spermatozoa that have been recovered after death can extend the use of genetically superior animals. The objective of this study was to evaluate the maximum period for which ovine spermatozoa could be successfully stored in refrigerated dilution medium post-mortem, with or without added seminal plasma. Three samples of spermatozoa collected in an artificial vagina from 10 rams, or from the tails of four epididymes from the same rams at the time of death (G0) and six (G6), twelve (G12), twenty-four (G24) and forty-eight (G48) hours after death were used. After recovery, the spermatozoa were refrigerated at 5°C in either control medium (CM) or control medium plus 20%homologous seminal plasma (SP) and evaluated for 72 hours from the start of refrigeration. The G48 samples had a lower(P <0.05) total motility (TM) and plasma membrane integrity in the hyposmotic test (HOST) than the other groups evaluated at all analyzed times. The TM decreased (P <0.05) after 24 hours of cooling in semen collected in AV, at G0 and G24 and after 48 hours of refrigeration in G6 and G12. The TM and HOST integrity and sperm morphology did not differ between samples refrigerated in CM or SP. In conclusion, it is possible to collect epididymal spermatozoa up to 24 hours after death. Sperm viability can be prolonged fora further 48 hours by refrigeration. However, total motility decreases from 24 hours after refrigeration and the supplementation of 20% seminal plasma to the extender has no effect on spermatozoa longevity.

The study aimed to determine the impact of equine chorionic gonadotropin (eCG) associated with different timed artificial insemination (TAI) protocols on the pregnancy rate (PR) in Bos indicus cows previously treated with progesterone. Five hundred and fifty-seven primiparous cows were subjected to the following treatments: on day 0 (d0), GeCGTW (group equine Chorionic Gonadotropin+Temporary Weaning;n=178) received 0,558 g intravaginal progesterone (P4)+1.0 mg of estradiol benzoate (EB) (IM); on d8 (P4 removal+0,075 mg D-cloprostenol + 400 IU eCG + TW for 48 h); on d10, TAI + calves return to dam; GeCGEB (group equine Chorionic Gonadotropin+Estradiol benzoate; n=176) the same as GeCGTW without TW + application of 1.0 mg of EB on d9; GeCGEC (group equine Chorionic Gonadotropin+Estradiol Cypionate; n=203), the same as GeCGTW without TW+1.5 mg EC (IM). On d35, post TAI, pregnancy diagnosis (PD) was performed. Non-pregnant animals remained under clean-up bulls for 90 days. After this period, the animals were subjected to PD using ultrasound. The PR of TAI was 51.1%, 47.1%, and 47.8% for GeCGTW, GeCGEB24, and GeCGEC (P>0.05) respectively. The PR under clean-up bulls was 88.3%, 47.3%, and 31.1% (P<0.05). The final PR (TAI+clean-up bulls) of the groups was 94.4%, 72.1%, and 64.0%, respectively (P<0.05). It was concluded that no differences in PR among the protocols related to TAI were detected; PR in the GeCGTW protocol under clean-up bulls was higher compared to others (P<0.05); the overall PR of cows subjected to TAI+clean-up bulls was significantly higher in GeCGTW than in the other groups.

A recuperação e a criopreservação de espermatozoides do epidídimo constituem alternativas viáveis para a preservação de material genético de animais valiosos. O objetivo deste estudo foi comparar o desempenho de dois diluentes comerciais Botu-Bov(r) (BB) e Bovimix(r) (BV), sobre a viabilidade pós-descongelação de espermatozoides do epidídimo de touros Tabapuã (Bos taurus indicus) pós-castração. Os espermatozoides foram colhidos da cauda de 20 epidídimos utilizando a técnica de fluxo retrógrado, centrifugados e diluídos com BB ou BV para posterior criopreservação a -196°C. Após a descongelação, as amostras foram avaliadas utilizando a análise computadorizada (CASA) e por análises microscópicas para a determinação da integridade de membranas plasmáticas, acrossomal e morfologia espermática. A avaliação estatística dos dados foi realizada pela análise de variância (ANOVA) com o pós-teste de comparações múltiplas de Tukey-Kramer, com nível de significância (P<0,05). Os resultados do movimento espermático avaliado pelo CASA, não diferiram para o diluente BB e BV. Também não foi observada diferença significativa entre os grupos no percentual de espermatozoides morfologicamente deformados, defeitos de acrossoma e espermatozoides com membrana plasmática íntegra após o descongelamento. Conclui-se que ambos os diluentes (BB e BV) são eficientes e podem ser utilizados na tecnologia do congelamento de espermatozoides colhidos da cauda do epidídimo de touros, não apresentando diferença na viabilidade espermática para os parâmetros estudados.

Recovery and cryopreservation of epididymal sperm is a viable alternative for preservation of genetically valuable animals. The aim of this study was to verify and to compare the effect of two commercial extenders for conventional semen on post-thawing viability of bovine epididymal sperm. For this purpose, the spermatozoa was recovered from the tail of 20 epididymis of Tabapuã bulls (Bos Taurus indicus) using retrograde flow method. After sperm recovery, the cells were centrifuged and divided for dilution with the diluents Botu-Bov(r) (BB) or Bovimix(r) (BV) for cryopreservation at -196°C. After thawing, all samples were evaluated using computer assisted sperm analysis (CASA), and by microscopic analysis for determination of integrity of plasma and acrossomal membrane and morphology. Statistical evaluation was performed by analysis of variance (ANOVA) with post-test for multiple comparisons, the Tukey-Kramer test, with significance level (P<0.05). The results of the sperm movement for diluent BB and BV evaluated with CASA, showed no difference for both (P>0.05). There was also no difference between the percentage of deformed sperm, acrosome defects and the sperm with intact plasma membrane after thawing with BB or BV. We conclude that both extenders (BB and BV) are efficient and can be used for freezing sperm collected from the epididymis of bulls, showing no difference for all the parameters studied.

The effect of an intramuscular versus intravenous administration of gonadotropin releasing hormone (GnRH) at fixed-time AI (FTAI) on the pregnancy rates of crossbred Bos indicus beef cows was evaluated. Pluriparous nursing calv cows (n=120) were synchronized as follows: d 0 cows received a 2.0 mg injection of estradiol benzoate (EB) and insertion of a controlled intravaginal progesterone releasing device containing 0.558 g of progesterone, d 8 removal of the progesterone device , a 0.15 mg injection of prostaglandin F2α (PGF), a 1.0 mg injection of EB, and 400 IU injection of equine chorionic gonadotropin. Fifty-four hr after PGF, all cows were exposed to FTAI and a 0.084 mg injection of GnRH was administered either via Vena caudalis (n=60), or via Longissimus dorsi (n=60). Cows were inseminated with the same sire and by a single AI technician. Pregnancy was determined by the transrectal ultrasonography on d 40 after AI. Cows receiving the intravenous administration of GnRH had higher (P = 0.04) pregnancy rates than the cows receiving the intramuscular injection of GnRH (65 vs 46.6%, respectively). It was concluded that the intravenous administration of GnRH at the time of AI improved the pregnancy rates of crossbred Bos indicus beef cows submitted to FTAI.

The aim of this study was to evaluate the viability of bull spermatozoa collected from the cauda epididymis stored at 18-20°C, which were compared with semen collected by electro-ejaculation method and preserved at 5°C. Ten pairs of testes from Tabapuã bulls were removed by orchiectomy and stored for 6 (G6), 12 (G12), 18 (G18), 24 (G24) and 30 (G30) h at room temperature (18-20°C). Seven days before orchiectomy, semen was collected by electro-ejaculation method. The sperm parameters evaluated were: sperm motility, vigor, concentration, morphology and acrosome defects. Sperm motility declined (p<0.05) when spermatozoa were stored for 30 h in the epididymis. The spermatozoa from the epididymis showed lower sperm motility than that of spermatozoa collected via electro-ejaculation. There was a little expressive decrease in sperm vigor and increased in morphological defects with storage time, but the acrosome integrity was not affected. Cold storage (5°C) maintained sperm viable for 15 to 40.8 h. Thus, it was possible to recover viable sperm with 41.25% of motility from the cauda epididymis stored at room temperature of 18-20°C for 30 h. There were differences between the ejaculated and epididymal sperm for the bulls and the conservation at 5°C allowed short-term preservation of the gametes.

The aim of this work was to study estrus synchronization and fixed time artificial insemination (FTAI) in dairy buffaloes during season anestrus. One hundred thirty-nine dairy buffaloes in seasonal anestrus were divided in two groups as G1(n=66) and G2(n=73). The protocols for both the groups were the same until day (D)14:D0 administration of 2.0 mg estradiol benzoate and implantation of progesterone device (P4) for 14 days; D14 removal of P4 plus 150 mg of cloprostenol and 400 IU of equine chorionic gonadotropin. On D16, G1 received 10 mg of buserelin and G2 100 mg deslorelin acetate. On D17, both the groups were submitted to FTAI. Ultrasonographic examinations of ovaries were performed on D0, D14, D16 and D17. Results showed that pregnancy rates in G1 and G2 were 20 and 41% (p<0.05) and the ovulation rates were 16.6 and 37%, respectively (p<0.05). The dominant follicle (DF) diameter on D16 was 7.9 mm in G1 and 8.9 mm in G2 (p>0.05). Thirty-five percent of the animals in G1 and 54.1% in G2 showed a diameter DF greater than 8.0 mm on D16 (p>0.05). Thus, it could be concluded that the protocols synchronized the estrus, leading the concentration of the parturitions in the period of low milk production. Deslorelin was more efficient than buserelin due the higher percentage of DF ovulation and higher pregnancy rates.

This study aimed to compare the pregnancy rate using the conventional artificial insemination (AI) or deep intracornual artificial insemination (DIAI), with low number of spermatozoa (4.0 million sperm) in 270 Nelore cows. The animals were divided in two groups (G: G1 (135 cows) conventional AI was performed (=semen deposition in the uterine body) and in G2 (135 cows) to DIAI, in ipsilateral horn where the dominant follicle in the ovary had previously been detected, by ultrasound examinations. For both the methods, a single artificial insemination was carried out after visual estrus observation, checked three times a day (morning, afternoon and evening). The pregnancy diagnosis after 45 days was conducted by ultrasound. Results showed a better pregnancy rate in the DIAI group (67.4% - p<0.01), when compared to conventional AI (48.8%) with low spermatozoa concentration.

The aim of this work was to prepare the mares for embryo transfer. In group 1 (G1,treated, n=15), recipient mares in anoestrus or in a transition period were treated with 5.0, 3.0 and 2.0 mg of estradiol cipionate at the days 0, 1 and 2 respectively, beginning at the day of ovulation (DO). From the fourth day on, the mares this group received long-acting progesterone weekly, up to the 120 day of gestation. At D8, the embryo was collected from the donor and transferred to the recipient. At D12, the ultrasonographyc diagnosis of pregnancy was carried out. The control group (G2, not treated, n=20) was formed by cycling recipient mares, displaying ovulation at each 2 to 3 days after the donors mare ovulation. The pregnancy rate was higher (p<0.05) in the mares from G2 (85.0%) than from G1 (53.3%). Thus, it could be concluded that the treated mares although showed lesser pregnancy rate than the cycling mare, were satisfactory alternative to be used mainly when there is no available cycling recipient.

The aim this study was to compare two protocols of induction for ovulation by desloreline acetate and hCG in Quarter Horse mares. The choice of the animals was based on the observations by the estrus, by rectal palpation of the ovaries and by ultrassonography of the follicular dynamics. After estrus detection and follicle control, the measurement of the follicles and the classification of uterus were carried out. The animals that had dominant follicle (diameter more than 35 mm) and swollen uterus were used. In these conditions, the mares received hCG or desloreline acetate. Once ovulation occurred, the artificial insemination was carried. Two groups were performed: G1 (20 animals) received 1.5 mg desloreline acetate and G2 (20 animals) received 1700 IU of hCG. Following 6h intervals, the control follicular was performed by ultrasonography. The follicular average diameter was 42.6 cm for the groups and set up a score of 0 to 3 of uterine edema displayed by the device as well as the time of ovulation. In conclusion, the desloreline acetate showed better performance than hCG, because the ovulation was induced in less time (nine hours than hCG) (p<0.05).The pregnancy rate was 80 and 75 %, respectively in G1 and G2.

O experimento objetivou estudar as diferentes características do epitélio vaginal de 55 cabras que, através de exame, conduzissem ao diagnóstico de gestação. Os animais foram divididos em dois grupos, sendo o 1º constituído de 35 animais submetidos a indução hormonal do estro. Cada fêmea desse grupo foi tratada com esponja vaginal impregnada com 50 mg de medroxiprogesterona, a qual permaneceu no interior da vagina durante 10 dias. No 8º dia foram administradas 500 UI de gonadotrofina coriônica humana (via submucosavulvar) e 250 µg de cloprostenol (via intramuscular). O grupo controle, composto por 25 animais, permaneceu sem qualquer tratamento. Procedeu-se à observação do estro, após a retirada das esponjas, sendo as fêmeas cobertas por monta natural dirigida. As coletas do material iniciaram-se no 20º dia pós cobertura, sendo repetidas a cada 10 dias, totalizando 8 por fêmea. O material para a citologia foi colhido com espátulas, na região anterior da vagina e corado pela técnica de Papanicolaou. As amostras para a histologia vaginal foram retiradas por biópsia da mesma região e coradas com HE e PAS com e sem digestão enzimática. Os exames histológicos comprovaram diferenças significativas quanto à espessura do epitélio e composição da camada de superfície do epitélio vaginal. Os animais não-gestantes apresentaram 8 a 10 camadas e superfície composta por células do tipo intermediário alto e/ou superficial, enquanto as gestantes manifestaram epitélio composto por apenas 4 a 5 camadas e células do tipo intermediário baixo na camada superficial, tornando possível diferenciar animais em gestação e não-gestação por esse método. Nos exames citológicos evidenciaram-se células dos tipos intermediário baixo, parabasal e cuboidal em ambos os grupos, não sendo possível diagnosticar gestação, anestro ou diestro.

The present research was developed in order to try a method of pregnancy diagnosis in goats, through the differentiable characteristics of the vaginal epithelium. A total of 55 goats were used. Materials for histologic and cytologic examination were taken from the anterior region of the vagina with a 10-day interval, initiating by day 20 until day 90 after mating. Biopsies were processed using standard techniques and stained with H.E. and PAS. Vaginal smears were stained by PAPANICOLAOU’s technique. During pregnancy, the epithelium was recorded as immature, being composed of 4 to 5-cell layers, with parabasal or low intermediate cells on the surface. The non-pregnant epithelium was composed of 8 to 10 cell-layers, showing high intermediate or superficial cells on the surface. This difference allowed to diagnose pregnancy and non-pregnancy status. Vaginal smears showed low intermediate, parabasal and cuboidal cells for both pregnant and non-pregnant groups.

No experimento foram utilizadas vacas da raça Simental procedentes de fazendas das Regiões Noroeste do Estado do Paraná e Sul do Mato Grosso do Sul, administrando-se o hormônio folículo estimulante (FSH) para a superovulação e utilizando-se o método cirúrgico para a inovulação dos embriões nas receptoras. No total foram efetuadas 103 colheitas e utilizadas 749 vacas receptoras. Foram colhidos 1.014 embriões sendo 81,8% destes transplantados e os restantes congelados ou rejeitados. Colheram-se em média 9,8 embriões por doadora sendo 8,0 transplantados, proporcionando 3,8 animais prenhes por colheita. Ocorreram 4,8% de colheitas sem embrião e 1,9% de óvulos não-fertilizados. Relativamente ao tamanho do corpo lúteo (CL) palpado nas vacas receptoras, os dados demonstraram que os Corpora lutea de médio e maior tamanho tiveram significativa influência sobre a taxa de prenhez em relação aos de menor tamanho (p<0,05) e 64,0% das receptoras ovularam no ovário do lado direito. A taxa de prenhez em relação à sincronia de estro entre doadoras e receptoras foi mais elevada entre os dias mais 2 e menos 2 (p>0,05) (o mais significa que o estro nas receptoras ocorreu após o da doadora e vice-versa), sendo muito baixa além destes limites. Os embriões classificados como ótimos e bons e inovulados influíram significativamente sobre o percentual de prenhez, e o total geral da taxa de gestação foi de 47,0%.

Simmental cows from northwest of the Paraná State and south of Mato Grosso do Sul, were used. A superovulation of donors’ cows was induced with FSH, and for embryos inovulation in recipient cows, the surgical method was used. Hundred and three recovered ova were employed and 749 recipients cows were utilized. From 1014 recovered embryos, 81.8% were transferred and the remaining embryos were frozen or rejected. The number of embryos recovered per cow averaged 9.8 ± 6.6 and transferred 8.0, resulting in 3.8 pregnancies per recovery. There were 4.8% of recoveries without embryos and 1.9 % of unfertilized ova. Middle and larger Corpora lutea in the recipients cows, had a significant influence on the pregnancy rate in relation to the smaller (p<0.05) and 64.0% of recipients cows had the ovulation on the right ovary. The pregnancy rate relative to the estrus synchronization between donors and receptors cows was higher between days + 2 and -2 (p>0.05) (the + sign indicates that the oestrus in the recipient started after that in the donor and vice versa), being very poor after this time. Embryos classified as very good and good and inovulated, influenced significantly the pregnancy rate. The general pregnancy rate was 47.0%.

O trabalho foi desenvolvido utilizando-se 18 vacas leiteiras recém-paridas, da bacia leiteira de Curitiba (PR). Os animais eram semanalmente examinados por palpação retal e aspectos de involução uterina e atividade ovariana eram verificados. O início dos exames ocorreu em torno do 7º dia pós-parto (p.p.) e estendeu-se até o 49º. Concomitantemente foram colhidas dos animais amostras de leite da ordenha matinal a cada quatro dias, para posterior determinação de progesterona, iniciando-se no 9º dia p.p. e estendendo-se até a 7ª semana. As dosagens da progesterona (P4) no leite magro foram realizadas pelo radioimunoensaio (RIA) em fase sólida. Os achados da pesquisa revelaram que a menor concentração de P4 detectada no leite foi de 0,01 ng/ml e a maior de 3,64 ng/ml, o 1º estro p.p. ocorreu no 28,5º dia e a detecção do 1º corpo lúteo (CL) teve lugar no 34,5º dia, o intervalo entre o estro e a 1ª elevação de P4 luteal foi em média de 5,5 dias, o intervalo parto/involução uterina deu-se no 24,1º dia, o 1º corpo lúteo p.p. gerou período da dominância de P4 de apenas 11,5 dias e a concentração média de P4 do 1º CL p.p. foi de 1,9 ng/ml, o 1º estro p.p. foi silencioso em 61,1% dos casos e o percentual de anestro dos animais durante o período da pesquisa foi de 33,3%.

This study was carried out on 18 calved dairy cows, near the town of Curitiba -PR- Brazil. The animals were submitted weekly to a rectal palpation of the genital tract and the uterine involution and ovarian activity were considered. The rectal palpations began from the 7th day postpartum till the 49th day. At the same time milk samples from the first morning milk were taken on the 9th day till the 7th week. The progesterone (P4) level determination of the milk was established by radioimmunassay. The findings of the research showed: the first postpartum oestrus was observed at the 28.5th day and the corpus luteum (CL) was detected on the 34.5th day. The period from oestrus to the first high progesterone level post partum was 5.5 days. The uterine involution period was carried on the 24.1th day. The progesterone dominant period was shorter and had duration of 11.5 days on the first oestrus cycle post partum. The progesterone concentration from the 1st Corpus luteum post partum was low (1.9 ng/ml milk). The anoestrus rate until the 49th day postpartum was 33.3% and the silent heat rate reached 61.1%.