Relationships between follicle and corpus luteum size and vascularization with ovulation, progesterone production, and pregnancy in Nellore beef cattle

ABSTRACT The objective of this study was to evaluate the relationships between preovulatory follicle (POF) and corpus luteum (CL) diameters, and POF and CL vascular perfusion with progesterone production, ovulation, and pregnancy in Nellore cows subjected to timed artificial insemination (TAI). Nellore cows (n = 201) were subjected to ovulation synchronization and later to ultrasound evaluation of POF and CL at the time of insemination (D0) and seven days later (D7), respectively. Females were divided into three categories according to the POF diameter assessed at the time of insemination: small (SF), medium (MF), and large (LF) follicles. The LF group had a greater number and intensity of pixels in the POF ultrasound exam compared with the SF group. The CL flow intensity and progesterone concentration were also higher in the LF group. The SF group showed lower flow intensity and lower ovulation rate compared with the others. When non-pregnant females were compared to pregnant ones, no difference was observed in any of the analyzed variables. The results show for the first time in Nellore cattle the relationship between the size of ovarian structures and blood flow (quantity and intensity) as well as the ability of the CL to produce progesterone. The intensity of the POF pixels proved to be relevant, demonstrating correlations with the size and flow of the CL, which were not found when evaluating only the number of pixels, thus revealing the importance of evaluating complementary characteristics of the flow.

Clinical application of Doppler ultrasound in the diagnosis of fertility problems in equines / Aplicações da ultrassonografia Doppler no diagnóstico de problemas de fertilidade em equinos

The use of different ultrasound modalities (color, power and pulsed Doppler) in clinical research has enhanced knowledge of reproductive pathophysiology in equine, in addition to improving the clinical diagnosis of reproductive disorders in both the stallion and the mare. In the stallion, color Doppler ultrasound has improved the diagnostic potential of conventional ultrasound, improving the differential diagnosis of pathologies such as testicular torsion (decrease or absence of blood flow in the cord) and orchitis (increased blood flow in the cord). The function of the testicle is highly dependent on the blood flow it receives; therefore, any vascular alterations can affect both the quality and production of sperm. In recent years there have been a greater number of studies in which Doppler ultrasound is used as a tool in the diagnosis of testicular dysfunction and in the monitoring of medical and surgical treatments. In the mare, ultrasound technology has allowed numerous advances in basic research regarding the vascular hemodynamics of the ovary and uterus. Moreover, it has become an indispensable tool in reproductive practice. Among the clinical applications of this technique in mares are the evaluation of CL (corpus luteum) functionality, being a useful tool in the selection of recipients in embryo transfer programs or the use of power Doppler in the diagnosis of pregnancy as early as 7 days postovulation prior to flushing. Finally, the incorporation of color and pulsed Doppler ultrasound into the examination improves the diagnosis of mares with endometritis due to a pathological increase in uterine blood flow.

Effect of hCG application at different moments of the estrous cycle on corpus luteum and uterine vascularization and serum progesterone concentration in mares

Establishment of pregnancy after embryo transfer is the ultimate goal of an embryo transfer program and increasing pregnancy rates and reducing pregnancy loss are mandatory. The utilization of treatments to improve conception rates in recipient mares has been the focus of several research groups over the last years and the results are controversial. Some studies using human chorionic gonadotrophin (hCG) found promising results. Our hypothesis was that hCG administration would cause an additional stimulation on luteal function, uterine and luteal vascularization and progesterone concentration, and the mares would have increased uterine and cervix tone. Therefore, in the present study the effects of hCG administration to induce ovulation, on day 0 (day of ovulation) or day 5 postovulation were evaluated on corpus luteum characteristics, reproductive tract vascularization, and serum progesterone concentration from ovulation until day 15 postovulation. Groups were: G1: (control) - no hCG; G2: 2500 IU of hCG to induce ovulation when a follicle greater than 35mm and uterine edema were detected; G3: 2500 IU hCG on day 0; G4: 2500 IU hCG on day 5 postovulation. Twelve mares were randomly assigned to each group, during consecutive cycles, in a Latin Square experimental design, in a total of 48 cycles. Doppler ultrasound evaluations were performed daily from day 0 until day 15 postovulation, including mesometrial vascularity, endometrial vascularity and corpus luteum vascularity. Blood samples were collected for serum progesterone concentration. Data was analyzed using the Proc Glimmix SAS Procedure for nonparametric variables and Proc Mixed for parametric parameters. There was no treatment effect for all variables studied (P > 0.05). Characteristics were only affected by day (P < 0.05). It can be concluded that hCG administration at the time points suggested in the current study did not alter the characteristics evaluated.

Effect of hCG application at different moments of the estrous cycle on corpus luteum and uterine vascularization and serum progesterone concentration in mares

Establishment of pregnancy after embryo transfer is the ultimate goal of an embryo transfer program and increasing pregnancy rates and reducing pregnancy loss are mandatory. The utilization of treatments to improve conception rates in recipient mares has been the focus of several research groups over the last years and the results are controversial. Some studies using human chorionic gonadotrophin (hCG) found promising results. Our hypothesis was that hCG administration would cause an additional stimulation on luteal function, uterine and luteal vascularization and progesterone concentration, and the mares would have increased uterine and cervix tone. Therefore, in the present study the effects of hCG administration to induce ovulation, on day 0 (day of ovulation) or day 5 postovulation were evaluated on corpus luteum characteristics, reproductive tract vascularization, and serum progesterone concentration from ovulation until day 15 postovulation. Groups were: G1: (control) - no hCG; G2: 2500 IU of hCG to induce ovulation when a follicle greater than 35mm and uterine edema were detected; G3: 2500 IU hCG on day 0; G4: 2500 IU hCG on day 5 postovulation. Twelve mares were randomly assigned to each group, during consecutive cycles, in a Latin Square experimental design, in a total of 48 cycles. Doppler ultrasound evaluations were performed daily from day 0 until day 15 postovulation, including mesometrial vascularity, endometrial vascularity and corpus luteum vascularity. Blood samples were collected for serum progesterone concentration. Data was analyzed using the Proc Glimmix SAS Procedure for nonparametric variables and Proc Mixed for parametric parameters. There was no treatment effect for all variables studied (P > 0.05). Characteristics were only affected by day (P < 0.05). It can be concluded that hCG administration at the time points suggested in the current study did not alter the characteristics evaluated.(AU)

Efficacy and limitations of different approaches to anticipate the diagnosis of pregnancy in cattle / Eficácia e limitações de diferentes abordagens para antecipar o diagnóstico de gestação em bovinos

The study evaluated sonographic and serologic exams performed for early (20 to 30d) diagnosis of pregnancy. One hundred-twenty (n= 120) bovine recipients were synchronized (estrous=D0) and timed embryo transferred (TET, D7) with fresh in vitro produced embryos. In the first trial (n= 46), diagnosis of pregnancy was performed on day 20 (D20) by detecting CL blood flow (BF) and by Pregnancy-Associated Glycoproteins (PAGs) serology. In the second trial (n= 30), pregnancy diagnosis was performed on D25 by ultrasound visualization of uterine contents and by PAGs serology. In the last trial, PAG's serology was performed on D30. Ultrasonographic detection of the uterine contents and embryo viability performed on D30 (DG30) was considered the gold standard. The PROC FREQ procedure was used to test the agreement between diagnostic methods. On D20, the Doppler ultrasonography of the CL had showed high sensitivity (100%), but only moderate specificity (53.3%). On the same day, serologic diagnostic had no agreement (k= -0.08, P< 0.46) with the gold standard, with very low sensitivity (6.3%). However, the sensitivity of the serologic exam increased dramatically (from 6.3 to 100%) from D20 to D25, and it contributed to detect false negatives from the ultrasound diagnosis, improving the overall accuracy from 90% to 96.7%.(AU)

O estudo foi planejado para correlacionar exames ultrassonográficos e sorológicos realizados para o diagnóstico precoce (20 a 30d) de gestação. Cento e vinte (n= 120) receptoras bovinas foram sincronizadas (estro=D0), e embriões frescos produzidos in vitro foram transferidos em tempo fixo (TETF, D7). No experimento 1 (n= 46), o diagnóstico de gestação foi realizado no D20, pela detecção do fluxo sanguíneo do CL e pela sorologia de glicoproteínas associadas à gestação (PAGs). No experimento 2 (n= 30), a detecção da gestação foi realizada por meio da visualização do conteúdo do útero e também pela sorologia para PAGs. No experimento 3, a sorologia para PAGs foi realizada no D30. Em todos os experimentos, a visualização ultrassonográfica da vesícula e da viabilidade embrionária, realizada no D30, foi considerada padrão-ouro. O procedimento PROC FREQ testou o nível de concordância dos métodos diagnósticos. No D20, o diagnóstico baseado na vascularização do CL mostrou alta sensibilidade (100%) e apenas moderada especificidade (53,3%). Nesse mesmo dia, o diagnóstico sorológico não apresentou concordância (k=-0,08, P<0,46) com o padrão-ouro, além de baixa sensibilidade (6,3%). No entanto, a sensibilidade do exame sorológico aumentou drasticamente (6,3 para 100%) do D20 para o D25, contribuindo para detectar falsos negativos diagnosticados pela ultrassonografia, melhorando a acurácia (90 para 96,7%).(AU)

Efficacy and limitations of different approaches to anticipate the diagnosis of pregnancy in cattle / Eficácia e limitações de diferentes abordagens para antecipar o diagnóstico de gestação em bovinos

The study evaluated sonographic and serologic exams performed for early (20 to 30d) diagnosis of pregnancy. One hundred-twenty (n= 120) bovine recipients were synchronized (estrous=D0) and timed embryo transferred (TET, D7) with fresh in vitro produced embryos. In the first trial (n= 46), diagnosis of pregnancy was performed on day 20 (D20) by detecting CL blood flow (BF) and by Pregnancy-Associated Glycoproteins (PAGs) serology. In the second trial (n= 30), pregnancy diagnosis was performed on D25 by ultrasound visualization of uterine contents and by PAGs serology. In the last trial, PAG's serology was performed on D30. Ultrasonographic detection of the uterine contents and embryo viability performed on D30 (DG30) was considered the gold standard. The PROC FREQ procedure was used to test the agreement between diagnostic methods. On D20, the Doppler ultrasonography of the CL had showed high sensitivity (100%), but only moderate specificity (53.3%). On the same day, serologic diagnostic had no agreement (k= -0.08, P< 0.46) with the gold standard, with very low sensitivity (6.3%). However, the sensitivity of the serologic exam increased dramatically (from 6.3 to 100%) from D20 to D25, and it contributed to detect false negatives from the ultrasound diagnosis, improving the overall accuracy from 90% to 96.7%.(AU)

O estudo foi planejado para correlacionar exames ultrassonográficos e sorológicos realizados para o diagnóstico precoce (20 a 30d) de gestação. Cento e vinte (n= 120) receptoras bovinas foram sincronizadas (estro=D0), e embriões frescos produzidos in vitro foram transferidos em tempo fixo (TETF, D7). No experimento 1 (n= 46), o diagnóstico de gestação foi realizado no D20, pela detecção do fluxo sanguíneo do CL e pela sorologia de glicoproteínas associadas à gestação (PAGs). No experimento 2 (n= 30), a detecção da gestação foi realizada por meio da visualização do conteúdo do útero e também pela sorologia para PAGs. No experimento 3, a sorologia para PAGs foi realizada no D30. Em todos os experimentos, a visualização ultrassonográfica da vesícula e da viabilidade embrionária, realizada no D30, foi considerada padrão-ouro. O procedimento PROC FREQ testou o nível de concordância dos métodos diagnósticos. No D20, o diagnóstico baseado na vascularização do CL mostrou alta sensibilidade (100%) e apenas moderada especificidade (53,3%). Nesse mesmo dia, o diagnóstico sorológico não apresentou concordância (k=-0,08, P<0,46) com o padrão-ouro, além de baixa sensibilidade (6,3%). No entanto, a sensibilidade do exame sorológico aumentou drasticamente (6,3 para 100%) do D20 para o D25, contribuindo para detectar falsos negativos diagnosticados pela ultrassonografia, melhorando a acurácia (90 para 96,7%).(AU)

Relationships between follicle and corpus luteum diameter, blood flow, and progesterone production in beef cows and heifers: preliminary results

The aim of the present study in beef cattle was to investigate potential differences in follicle size and follicle wall-blood flow between cows and heifers and to compare follicle wall-blood flow between smaller and larger follicles. Cows and heifers were treated with a synchronization protocol and follicles and CLs were measured and evaluated for blood flow. Pregnancy diagnosis was performed on day 50 of the protocol. Cows had larger (P 0.05) in CL diameter, CL blood flow, and plasma progesterone concentrations. Moderate correlations between follicle diameter and follicle blood flow were observed for cows (r = 0.51; P 0.05) among all follicle diameter categories. In conclusion, synchronized beef cows and pregnant cows had larger follicles and greater blood flow than heifers and non-pregnant cows, and follicle wall blood flow was closely associated with increasing follicle diameter.

Novel prospects for evaluation of follicle wall blood flow using color-Dopplerultrasonography

The goal of this study was to develop anobjective method for evaluation of ovarian follicle wallblood flow in cattle. Two subjective methods were used:(I) real-time ultrasound evaluations performed by oneoperator in the barn and (II) video clip evaluationsperformed by four operators in the laboratory. Thefollowing objective methods evaluated in the laboratorywere used for comparison: (I) percentage of follicle wallcircumference under blood flow (WUF) and (II) pixelarea of color-Doppler signals. Cows (n = 21) weresubmitted to a synchronization protocol, follicles ≥7 mmwere measured, and blood flow was evaluated every 12 huntil ovulation using color-Doppler ultrasonography. Nodifference (P > 0.05) was observed among laboratoryoperators from day 2 of training onwards. Therefore,an average score of all operators was used forcomparisons among different methods. Both subjectiveand objective methods of evaluation showed anincrease (P < 0.0001) in follicle blood flow over time.Higher (P < 0.001) correlations were obtained betweenWUF and subjective laboratory evaluation thanbetween WUF and pixel area or WUF and subjectivebarn data. Higher (P < 0.0003) correlation coefficientswere observed for WUF than for the pixel area whencompared with the barn (r = 0.70 vs. r = 0.42) orlaboratory (r = 0.84 vs. r = 0.62) data. Subjectiveevaluations at the laboratory and barn producedstronger correlations with WUF (P < 0.0008) than withpixel area (P < 0.01). In conclusion, WUF is aneffective and reliable method for objective evaluationof follicle wall blood flow in cows.

Relationships between follicle and corpus luteum diameter, blood flow, and progesterone production in beef cows and heifers: preliminary results

The aim of the present study in beef cattle was to investigate potential differences in follicle size and follicle wall-blood flow between cows and heifers and to compare follicle wall-blood flow between smaller and larger follicles. Cows and heifers were treated with a synchronization protocol and follicles and CLs were measured and evaluated for blood flow. Pregnancy diagnosis was performed on day 50 of the protocol. Cows had larger (P < 0.008) follicles than heifers. Cows, heifers, and pregnant and non-pregnant cows did not differ (P > 0.05) in CL diameter, CL blood flow, and plasma progesterone concentrations. Moderate correlations between follicle diameter and follicle blood flow were observed for cows (r = 0.51; P < 0.002) and heifers (r = 0.61; P < 0.0001). Pregnant cows tended (P < 0.1) to have larger follicles between 12 to 60 h before ovulation, and had larger (P < 0.05) follicles than non-pregnant cows at hour 24 before ovulation and at hour 12 before maximum values. Pregnant cows had greater (P < 0.05) follicle blood flow than non-pregnant cows at hours −36 and −24 before maximum values. Follicle blood flow was greater (P < 0.002) in the large follicles compared with the small follicles, and tended (P < 0.06) to be greater than in medium follicles. Moderate to strong correlations were found between follicle blood flow and diameter of small (r = 0.59; P < 0.002), medium (r = 0.50; P < 0.02), and large (r = 0.71; P < 0.0001) follicles. Pregnancy rates were similar (P > 0.05) among all follicle diameter categories. In conclusion, synchronized beef cows and pregnant cows had larger follicles and greater blood flow than heifers and non-pregnant cows, and follicle wall blood flow was closely associated with increasing follicle diameter.(AU)

Novel prospects for evaluation of follicle wall blood flow using color-Dopplerultrasonography

The goal of this study was to develop anobjective method for evaluation of ovarian follicle wallblood flow in cattle. Two subjective methods were used:(I) real-time ultrasound evaluations performed by oneoperator in the barn and (II) video clip evaluationsperformed by four operators in the laboratory. Thefollowing objective methods evaluated in the laboratorywere used for comparison: (I) percentage of follicle wallcircumference under blood flow (WUF) and (II) pixelarea of color-Doppler signals. Cows (n = 21) weresubmitted to a synchronization protocol, follicles ≥7 mmwere measured, and blood flow was evaluated every 12 huntil ovulation using color-Doppler ultrasonography. Nodifference (P > 0.05) was observed among laboratoryoperators from day 2 of training onwards. Therefore,an average score of all operators was used forcomparisons among different methods. Both subjectiveand objective methods of evaluation showed anincrease (P < 0.0001) in follicle blood flow over time.Higher (P < 0.001) correlations were obtained betweenWUF and subjective laboratory evaluation thanbetween WUF and pixel area or WUF and subjectivebarn data. Higher (P < 0.0003) correlation coefficientswere observed for WUF than for the pixel area whencompared with the barn (r = 0.70 vs. r = 0.42) orlaboratory (r = 0.84 vs. r = 0.62) data. Subjectiveevaluations at the laboratory and barn producedstronger correlations with WUF (P < 0.0008) than withpixel area (P < 0.01). In conclusion, WUF is aneffective and reliable method for objective evaluationof follicle wall blood flow in cows.(AU)

Influência do Temperamento de Vacas Nelores Sobre a Perfusão Vascular do Folículo e do Corpo Lúteo e Sobre a Fertilidade, Quando Submetidas à IATF

O presente estudo foi dividido em dois capítulos sendo que no primeiro objetivou-se avaliar a influência do temperamento sobre a perfusão vascular do folículo pré-ovulatório (FPO) e do corpo lúteo (CL) assim como sobre a produção de progesterona (P4) e sobre a taxa de concepção de vacas Nelores submetidas à IATF. Já no segundo capítulo, o objetivo foi estudar as relações entre o diâmetro do FPO e do CL com a quantidade e intensidade do fluxo sanguíneo nestas estruturas, produção de P4 e a fertilidade de vacas Nelores submetidas à IATF. No primeiro experimento, 201 fêmeas foram submetidas à sincronização da ovulação e, no momento da IA, foram determinados o escore de brete e velocidade de saída deste para avaliação do temperamento. De acordo com os escores individuais, os animais foram classificados em temperamento adequado (ADQ) ou excitável (EXC). Amostras de sangue foram coletadas para dosagem de cortisol e progesterona. As avaliações ultrassonográficas por Doppler colorido foram realizadas para determinar o diâmetro, volume e a vascularização do FPO e do CL no momento da IA (D0) e sete dias (D7) após, respectivamente. As taxas de sincronização, ovulação e de concepção foram comparadas entre os grupos ADQ e EXC. As variáveis número de pixels do FPO no momento da IA (p=0,01), intensidade dos pixels na parede do folículo (p=0,01), diâmetro (p=0,02) e volume (p=0,01) do folículo pré-ovulatório no momento da IA foram todas menores para o grupo de vacas do grupo EXC, enquanto as concentrações de cortisol foram maiores no grupo de vacas excitáveis, o que foi relacionado ao estresse durante o manejo da IATF. O número e a intensidade dos pixels do CL não apresentaram diferença entre os grupos, enquanto o diâmetro e volume também foram menores (p=0,01) para o grupo EXC. Não foi observada diferença entre os grupos para as taxas de sincronização, ovulação e de concepção assim como para a concentração de progesterona no D7. Pode-se concluir que vacas Nelores de temperamento excitável apresentam menor fluxo sanguíneo folicular e redução no tamanho do folículo e do corpo lúteo sem, no entanto, comprometer a fertilidade. No segundo experimento, foram determinados o diâmetro e o volume do FPO (D0) e CL (D7) de 201 vacas submetidas a IATF, assim como a quantidade e intensidade de pixels coloridos presente nelas. Adicionalmente, amostras de sangue também foram coletadas no D7 para dosagem de P4. Pará análise dos dados, as vacas foram divididas em vazias e gestantes e também de acordo com o diâmetro do FPO: vacas de folículo pequeno, com diâmetro < 11mm (FP; n= 35); vacas de folículo médio, com diâmetro entre 11 e 14mm (FM; n=84) e vacas de folículo grande, com diâmetro > 14mm (FG; n= 70). As variáveis ultrassonográficas do FPO e do CL, bem como a concentração de P4 foram comparadas entre os grupos FP, FM e FG e entre fêmeas vazias e gestantes. Foram encontradas diferenças entre os grupos FP, FM e FG para diâmetro e volume do FPO e do CL, demonstrando que folículos maiores também originam corpos lúteos maiores. O grupo FG apresentou maior quantidade e intensidade de pixels no FPO em relação ao FP. A intensidade de fluxo no CL e a concentração de P4 também foram maiores no FG. O grupo FP apresentou menor intensidade de fluxo e taxa de ovulação em relação aos demais, embora a taxa de concepção tenha sido semelhante para todos. Foram encontradas correlações fracas entre o tamanho do FPO e do CL assim como entre o diâmetroe volume do CL com sua quantidade pixels e concentração de P4. Além de correlação moderada entre o diâmetro e sua intensidade de pixels. Não houve diferença entre fêmeas vazias e gestantes para todas as variáveis analisadas. Os resultados confirmam a presença de relações entre o tamanho das estruturas ovarianas e a quantidade e intensidade de fluxo destas, bem como a sua capacidade de produzir progesterona. A intensidade dos pixels do FPO mostrou-se relevante, demonstrando correlações com o tamanho e o fluxo do CL, que não foram encontradas avaliando somente a quantidade de pixel, revelando a importância de avaliar características complementares do fluxo.

The present study was divided into two chapters, the first aimed to evaluate the influence of temperament on the vascular perfusion of the preovulatory follicle (POF) and the corpus luteum (CL) as well as on progesterone (P4) production and conception rate of Nellore cows submitted to TAI. In the second chapter, the objective was to study the relationship between the diameter of the POF and CL with the quantity and intensity of blood flow, P4 production and the fertility of Nellore cows submitted to TAI. In the first experiment, 201 cows were subjected to synchronization of ovulation and, at the time of AI. In the first experiment, 201 females were subjected to synchronization of ovulation and, at the time of AI, the chute score and exit speed were determined to assess temperament. According to the individual scores, the animals were classified in adequate (ADQ) or excitable (EXC) temperament. Blood samples were also collected to measure cortisol and P4. Color Doppler ultrasound evaluations were performed to determine the diameter, volume, and vascularization of POF and CL at the time of AI (D0) and seven days (D7) later, respectively. The synchronization, ovulation and conception rates were compared between the ADQ and EXC groups. The variables number of POF pixels at the time of AI (p = 0.01), pixel intensity on the follicle wall (p = 0.01), diameter (p = 0.02) and volume (p = 0.01) of the POF at the time of AI were all lower for the group of cows in the EXC group, while cortisol concentrations were higher in the group of excitable cows, which was related to stress during the management of IATF. The number and intensity of the pixels of the CL showed no difference between the groups, while the diameter and volume were also lower (p = 0.01) for the EXC group. There was no difference between groups for synchronization, ovulation, and conception rates as well as for P4 concentration on D7. It can be concluded that Nellore females of excitable temperament have less follicular blood flow and reduction in the size of the follicle and corpus luteum without, however, compromising fertility. In the second experiment, the diameter and volume of the POF (D0) and CL (D7) of 201 cows subjected to TAI were determined, as well as the amount and intensity of colored pixels present in them. In addition, blood samples were also collected on D7 for P4 measurement. For data analysis, the females were divided into nonpregnant and pregnant and also according to the diameter of the POF: females of small follicle, with diameter <11mm (SF; n = 35); females of medium follicle, with diameter between 11 and 14mm (MF; n = 84) and females of large follicle, with diameter 14mm (LF; n = 70). The ultrasound variables of POF and CL, as well as the P4 concentration were compared between the groups SF, MF and LF and between nonpregnant and pregnant cows. Differences were found between the SF, MF and LF groups for the diameter and volume of the POF and CL, demonstrating that larger follicles also originate larger luteal bodies. The LF group showed a higher amount and intensity of pixels in the POF compared to the SF. The flow intensity in the CL and the P4 concentration were also higher in the LF. The SF group had lower flow intensity and ovulation rate compared to the others, although the conception rate was similar for all. Weak correlations were found between the size of the POF and the CL as well as between the diameter and volume of the CL with its pixel count and P4 concentration. In addition to a moderate correlation between the diameter and its pixel intensity. There was no difference between nonpregnant and pregnant cows for all variables analyzed. The resultsconfirm the presence of relationships between the size of the ovarian structures and the quantity and intensity of their flow, as well as their ability to produce progesterone. The intensity of the POF pixels was shown to be relevant, showing correlations with the size and flow of the CL, which were not found by evaluating only the pixel quantity, revealing the importance of evaluating complementary flow characteristics.

RESPOSTA SUPEROVULATÓRIA E PRODUÇÃO IN VIVO DE EMBRIÕES EM DIFERENTES RAÇAS OVINAS NATIVAS BRASILEIRAS

Com finalidade de aumentar o rebanho e a variabilidade genética, produtores de ovinos, estão optando pela biotécnica de múltipla ovulação e transferência de embriões. Porém, está técnica apresenta resultados imprevisíveis, devido a fatores intrínsecos e extrínsecos, dos quais destaca-se o efeito raça. Portanto, esse estudo avaliou o efeito raça sobre a resposta superovulatória e a produção in vivo de embriões em ovelhas nativas brasileiras (Morada Nova, Santa Inês e Somalis Brasileira). Trinta ovelhas multíparas (n = 10/ raça) foram submetidas a protocolo de nove dias de duração à base de progesterona e tratamento superovulatório com 133 mg de FSH. Nos Dias 11 (36 horas após a remoção do dispositivo) e 15 (12 horas antes da colheita não cirúrgica de embriões), os animais foram submetidos às análises ultrassonográficas em modo-B e Doppler para avaliação da população ovariana e características de perfusão ovariana. A colheita transcervical dos embriões foi realizada 7 dias após a remoção do dispositivo. Os dados foram submetidos aos testes ANOVA, teste de Tukey e teste de Bartlett; e as correlações foram testadas pelo teste de Spearman (p < 0,05). O número de folículos médios (4,0 a 5,99 mm) no Dia 11 foi maior (p = 0,0025) em ovelhas Santa Inês e Somalis Brasileira comparadas às ovelhas Morada Nova. O número de corpos lúteos e o status Superovulatório no Dia 15 foram maiores (p < 0,0001) para ovelhas Santa Inês (15,3 ± 1,4 e 2,4 ± 0,2), seguido pelas ovelhas Somalis Brasileira (10,4 ± 0,8 e 1,5 ± 0,2) e então pelas ovelhas Morada Nova (5,5 ± 1,6 e 0,8 ± 0,3). A área ovariana (p = 0,02), área de fluxo sanguíneo (p= 0,05) e porcentagem da área dopller (p = 0,007) tiveram maiores valores no Dia 15 em relação ao Dia 11 para as ovelhas Santa Inês e Somalis Brasileira. Para as características de fluxo sanguíneo de alta velocidade foram encontrados maiores valores no Dia 15 em relação ao Dia 11, independentemente da raça. Para cada raça foram registradas distintas correlações entre características ovarianas e resposta superovulatória e produção de embriões. Em conclusão, houve influência da raça sobre as respostas superovulatórias e características da vascularização ovariana. No entanto, a produção de embriões foi similar entre as raças de ovelhas nativas brasileiras.

In order to increase the herd and genetic variability, sheep producers are opting for multiple ovulation and embryo transfer. This technique, however, provides unpredictable results due to intrinsic and extrinsic factors. Among these factors the breed effect stands out. The present study assessed if the breed effect influences the follicular population, ovarian blood perfusion, superovulatory response, and the in vivo production of embryos in native Brazilian sheep breeds (Morada Nova, Santa Inês and Somalis Brasileira). Thirty multiparous ewes (n=10/breed) received intravaginal devices impregnated with 0.33 g of progesterone for nine days and superovulatory treatment with 133 mg of FSH started 60 h before the device removal. On Days 11 (36h after device removal) and 15 (12h before nonsurgical embryo recovery, NSER) the ewes were submitted to B-mode and Doppler ultrasonography to evaluate the ovarian population and characteristics of ovarian blood perfusion. NSER was performed seven days after device removal. The number of medium follicles (4.0 to 5.99 mm) on Day 11 was greater (p=.0025) in Santa Inês and Somalis Brasileira compared to Morada Nova ewes. The number of corpora lutea and superovulatory status on Day 15 was greater (p<0.0001) for Santa Inês (15.3±1.4 and 2.4±0.2), followed by Somalis Brasileira (10.4±0.8 and 1.5±0.2) and then Morada Nova ewes (5.5±1.6 and 0.8±0.3). The ovarian area (DA, p=.02), blood flow area (TA, p=.05), and DA/TAx100% (p=.007) had greater values on Day 15 in relation to Day 11 for the Santa Inês and Somalis Brasileira ewes. The high-velocity blood flow characteristics had greater values on Day 15 in relation to Day 11, regardless of breed. For each breed, different correlations were recorded between ovarian blood flow characteristics and superovulatory response and embryo yield. In conclusion, there was an influence of the breed effect on the number of medium follicles, superovulatory responses and for characteristics of ovarian blood perfusion; however, the in vivo embryo production was similar among native Brazilian sheep breeds.

Follicle and corpus luteum size and vascularity as predictors of fertility at the time of artificial insemination and embryo transfer in beef cattle / Tamanho e vascularização do folículo e corpo lúteo como preditores de fertilidade após inseminação artificial e transferência de embriões em gado de corte

Two ultrasound based fertility prediction methods were tested prior to embryo transfer (ET) and artificial insemination (AI) in cattle. Female bovines were submitted to estrous synchronization prior to ET and AI. Animals were scanned immediately before ET and AI procedure to target follicle and corpus luteum (CL) size and vascularity. In addition, inseminated animals were also scanned eleven days after insemination to target CL size and vascularity. All data was compared with fertility by using gestational diagnosis 35 days after ovulation. Prior to ET, CL vascularity showed a positive correlation with fertility, and no pregnancy occurred in animals with less than 40% of CL vascularity. Prior to AI and also eleven days after AI, no relationship with fertility was seen in all parameters analyzed (follicle and CL size and vascularity), and contrary, cows with CL vascularity greater than 70% exhibit lower fertility. In inseminated animals, follicle size and vascularity was positive related with CL size and vascularity, as shown by the presence of greater CL size and vascularity originated from follicle with also greater size and vascularity. This is the first time that ultrasound based fertility prediction methods were tested prior to ET and AI and showed an application in ET, but not in AI programs. Further studies are needed including hormone profile evaluation to improve conclusion.(AU)

Duas técnicas de predição de fertilidade, baseadas em ultrassonografia, foram testadas no momento da transferência de embriões (TE) e inseminação artificial (IA) em bovinos. Fêmeas bovinas foram submetidas a protocolos de sincronização de estro para TE e IA. Os animais foram escaneados por ultrassonografia imediatamente antes do procedimento de TE e IA para identificar o tamanho e vascularização do folículo e corpo lúteo (CL). Além disso, os animais inseminados foram escaneados onze dias após a inseminação para identificar o tamanho e vascularização do CL. Todos os dados foram comparados com a fertilidade utilizando-se do diagnóstico gestacional 35 dias após a ovulação. No momento da TE, a vascularização do CL apresentou-se positivamente relacionada com a fertilidade, sendo que animais com menos de 40% de vascularização do CL não ficaram gestantes. No momento da IA, assim como onze dias após a IA, nenhuma relação foi encontrada entre fertilidade e os parâmetros analizados (tamanho e vascularização do folículo e CL), enquanto que contrariamente, houve uma queda na fertilidade em vacas com vascularização do CL acima de 70%. Nos animais inseminados, o tamanho e vascularização do folículo foi positivamente relacionado ao tamanho e vascularização do CL, demonstrado pela presença de um CL maior e mais vascularizado proveniente de um folículo maior e mais vascularizado. O presente estudo é o primeiro a mostrar métodos de predição de fertilidade baseados em ultrassonografia no momento da IA e TE, demonstrando uma aplicabilidade prática no momento da TE. Novos estudos são necessários para suportar os resultados mostrados, incluindo análises hormonais.(AU)

Estudos para avaliar a eficiência do protocolo de ressincronização super precoce

Resumo: O objetivo do presente estudo foi avaliar os fatores que afetam a eficiência do protocolo de ressincronização super precoce em que o diagnóstico da gestação é realizado com ultrassonografica color doppler. No experimento 1, objetivou-se avaliar a eficiência do uso da P4 injetável (Afisterone ou Sincrogest) em novilhas (50mg IM) e vacas (100mg IM) no início do protocolo de ressincronização associado a um dispositivo intravaginal de P4 no dia 14 após a IATF. Não houve efeito de tratamento na taxa de prenhez à ressincronização de novilhas Nelore [Controle 34,7% (61/176); Afisterone 38,0% (70/184) e Sincrogest 38,4% (63/164); P = 0,53], em novilhas cruzadas Nelore x Angus [Controle 44,9% (35/78); Afisterone 48,4% (44/91) e Sincrogest 43,2% (35/81); P = 0,53] e em vacas [Controle 34,8% (116/333), Afisterone 31,2% (99/317) e Sincrogest 35,5% (118/332); P = 0,19]. Ainda, verificou-se maior taxa de prenhez das novilhas com maior ETR (escore de trato reprodutivo; escala de 1 a 5), indicando que novilhas com maior desenvolvimento uterino e ovariano apesentam maior taxa de prenhez [ETR 3 = 49,1% (54/110) vs ETR 4 = 57,3% (229/400) vs ETR 5 = 65,2% (137/210); P = 0,01]. Houve efeito da manifestação de estro na taxa de prenhez entre a retirada do dispositivo de P4 e a IATF na ressincronização em novilhas [presença de estro = 52,2% (96/184) vs. ausência de estro 27,3% (18/166); P = 0,0003] e em vacas [presença de estro = 43,3% (116/268) vs. ausência de estro 19,1% (39/204); P= 0,0001]. No experimento 2, objetivou-se comparar a eficiência do modelo de ressincronização super precoce (com início da ressincronização 14 dias após a IATF) em relação ao modelo precoce (com início da ressincronização 22 dias após a IATF) em novilhas Nelore e em relação ao modelo tradicional (com início da ressincronização 30 dias após a IATF) em novilhas cruzadas Nelore x Angus. Não houve efeito de modelo de ressincronização precoce na taxa de prenhez da primeira IATF [super precoce = 52,9% (176/333) vs precoce = 51,7% (182/352);P= 0,78], da segunda IATF [super precoce = 46% (52/113) e precoce = 42,4 (72/10); P= 0,54] e na taxa de prenhez acumulada [super precoce = 68,5% (228/333) e precoce = 72,2% (254/352); P= 0,29]. Houve efeito na taxa de prenhez a primeira IATF entre os modelos super precoce e tradicional [super precoce = 57,9% (103/178) e tradicional = 41,2% (68/165); P= 0,0016]. Entretanto, não houve efeito do modelo de ressincronização na taxa de prenhez da segunda IATF [(super precoce = 39,1% (25/64) e tradicional = 32% (31/97); P= 0,17]. Ao final, houve efeito do modelo de ressincronização na prenhez acumulada [(super precoce = 71,9% (128/178) e tradicional = 60% (99/165); P= 0,02]. Conclui-se que o tratamento com P4 injetável no início do protocolo de ressincronização super precoce não aumentou a taxa de prenhez a IATF de novilhas Nelore, de novilhas cruzadas (Nelore x Angus) e de vacas Nelore. Ainda, o modelo de ressincronização super precoce apresenta eficiência semelhante a dos modelos precoce e tradicional.

Abstract: The objective of the present study was to evaluate the factors that affect the efficiency of the super precocious resynchronization protocol, in which pregnancy diagnosis is performed using Color Doppler ultrasound. On experiment 1, the objective was to evaluate the efficiency of the use of injectable P4 (Afisterone or Sincrogest) in heifers (50mg I.M.) and cows (100mg I.M.) at the onset of the resynchronization protocol associated with an intravaginal P4 device on day 14 post-TAI. No treatment effect was observed for pregnancy rate at resynchronization of Nellore heifers [Control 34.7% (61/176); Afisterone 38.0% (70/184) and Sincrogest 38.4% (63/164); P = 0.53], in crossbred Nellore x Angus heifers [Control 44.9% (35/78); Afisterone 48.4% (44/91) and Sincrogest 43.2% (35/81); P = 0.53] and cows [Control 34.8% (116/333), Afisterone 31.2% (99/317) and Sincrogest 35.5% (118/332); P = 0.19]. In addition, a higher pregnancy rate was observed for heifers with a higher RTS (reproductive tract scoring, scale of 1 to 5), indicating that heifers with greater uterine and ovarian development have higher pregnancy rate prenhez [RTC 3 = 49.1% (54/110) vs RTS 4 = 57.3% (229/400) vs RTS 5 = 65.2% (137/210); P = 0.01]. There was an effect of estrus on pregnancy rate manifestation between P4 device removal and resynchronization TAI for heifers [presence of estrus = 52.2% (96/184) vs. absence of estrus 27.3% (18/166); P = 0.0003] and cows [presence of estrus = 43.3% (116/268) vs. absence of estrus 19.1% (39/204); P= 0.0001]. On experiment 2, the objective was to evaluate the efficiency of the super precocious resynchronization model (beginning resynchronization 14 days post-TAI) in relation to the precocious model (beginning resynchronization 22 days post-TAI) in Nellore heifers and in relation to the traditional model (beginning resynchronization 30 days post-TAI) in crossbred Nellore x Angus heifers. No effect of model of precocious resynchronization was observed on pregnancy rate of the first TAI [super precocious = 52.9% (176/333) vs precocious = 51.7% (182/352);P= 0.78], of the second TAI [super precocious = 46% (52/113) and precocious = 42.4 (72/10); P= 0.54] and accumulated pregnancy rate [super precocious = 68.5% (228/333) and precocious = 72.2% (254/352); P= 0.29]. There was an effect on pregnancy rate of the first TAI between the super precocious and traditional models [super precocious = 57.9% (103/178) and traditional = 41.2% (68/165); P= 0.0016]. However, no effect of the model of resynchronization was observed on the pregnancy rate of the second TAI [(super precocious = 39.1% (25/64) and traditional = 32% (31/97); P= 0.17]. Finally, there was an effect of the model of resynchronization on accumulated pregnancy rate [(super precocious = 71.9% (128/178) and traditional = 60% (99/165); P= 0.02]. It is concluded that treatment with injectable P4 at on onset of the super precocious resynchronization protocol did not improve pregnancy rate of TAI in Nellore heifers, Crossbred (Nellore x Angus) heifers and Nellore cows. Additionally, the super precocious resynchronization model presents similar efficiency to the precocious and traditional models.

EFEITOS DO ESTRESSE CALÓRICO SOBRE PARÂMETROS FISIOLÓGICOS, ESTRUTURAS OVARIANAS, E ATIVIDADE DE RUMINAÇÃO EM ANIMAIS COM FENÓTIPOS E VALORES GENÉTICOS DISTINTOS PARA TERMOTOLERÂNCIA

Objetivou-se com o presente estudo avaliar os efeitos do estresse calórico sobre parâmetros fisiológicos (temperatura vaginal-TVg., frequência respiratória-FR e frequência cardíaca-FC), índice de pulsatilidade (IP) e índice de resistência (IR) de artéria Ilíaca, bem como a influência do estresse calórico sobre a vascularização de folículos pré-ovulatórios e do corpo lúteo em animais previamente classificados como resistentes ou sensíveis ao estresse calórico. Também objetivou-se avaliar os efeitos do estresse calórico no tempo total e no padrão diário de ruminação e degradabilidade ruminal da matéria seca da dieta em vacas Girolando não lactantes. Vinte vacas multíparas foram estabuladas em câmara climática (índice de temperatura e umidade - ITU - médio 83,13) ou em freestall (ITU médio 66,51), distribuídas aleatoriamente em delineamento de reversão (crossover). As vacas foram alimentadas para mantença com silagem de milho ad libtum e 1,0 kg/dia de concentrado. Ultrassom Doppler foi utilizado para avaliar IP/IR e folículos pré-ovulatórios e corpo lúteo. Para registro da atividade de ruminação foi utilizado um sensor de ruminação preso a um colar. A cinética de degradabilidade ruminal in situ da matéria seca (DMS) foi avaliada pela incubação de amostras do concentrado, do volumoso e da dieta no rúmen por 6, 24, 48 e 96 horas. TVg e FR foram significativamente maiores em animais estabulados em ambiente de estresse calórico (P<0,05 e P<0,001; respectivamente), FC foi maior em um dia para animais no freestall (P=0,001), IP e IR foram maiores para animais resistentes em estresse calórico (P<0,05), área do corpo lúteo foi maior para animais resistentes no freestall (P<0,05). O ambiente não teve efeito no tamanho ou fluxo sanguíneo de folículo préovulatório (P>0,05). O efeito do ambiente foi significativo (P<0,001) para o tempo de ruminação. Foram observadas reduções de 8,6% da DMS do concentrado, 9,4% da fração potencialmente degradável do concentrado, 4,1% da DMS da dieta em animais expostos ao estresse calórico. Conclui-se que o ITU elevado pode afetar negativamente parâmetros fisiológicos, o tamanho do corpo lúteo, a ruminação e os parâmetros de cinética ruminal em vacas Girolando não lactantes.

The aim of this study was to evaluate the effects of the heat stress in physiologic parameters (vaginal temperature, respiratory frequency and cardiac frequency), pulsatility index and resistance index of Iliac artery, as well the heat stress influence under pre-ovulatory follicles and Corpus Luteum vascularization in animals previously classified as a resistant or sensible to heat stress. It was also aimed to evaluate the time and daily pattern of rumination and the in situ degradability on dry cows Holstein-Gyr. Twenty crossbreeding were housed in Climatic Chamber (THI medium 83.13) and Freestall (THI medium 66.51), randomly distributed in a crossover design. The cows were fed for maintenance with corn silage ad libtum and 1 kilogram of concentrate. Doppler ultrasound was utilized to evaluate pulsatility and resistance index, pre-ovulatory follicles and Corpus Luteum. To measure the rumination it was used a rumination sensor fixed in a collar. The in situ ruminal dry matter degradability kinetics (DMD) was evaluated by the incubation of concentrate, silage, and diet samples in the rumen for 6, 24, 48 and 96 hours. Vaginal temperature and respiratory frequency were significantly higher for the animals housed in heat stress environmental (P<0.05 e P<0.001; respectively), cardiac frequency was higher in a day for animals in the freestall (P=0.001), pulsatility and resistance index were higher for resistant animals in heat stress (P<0.05), Corpus Luteum were greater for resistant animals in (P<0,05). The environmental had no effect in the pre-ovulatory follicle size or blood flow (P>0,05). The environmental effects was significative (P<0,001) for the rumination time. Reductions of 8.6% of the DMD from the concentrate, 9.4% of the potentially degradable fraction from concentrate, 4.1% of the DMD from the diet in animals exposed to heat stress were observed. Elevated THI can negatively affect physiological parameters, the size of corpus Luteum, the rumination and the parameters of ruminal kinetics in dry Holstein-Gyr cows.

AVALIAÇÃO DOS PARÂMETROS ULTRASSONOGRÁFICOS TESTICULARES, DA MITOCÔNDRIA ESPERMÁTICA E DA FRAGMENTAÇÃO DE DNA ESPERMÁTICO EM CÃES SADIOS

A ultrassonografia tem-se tornado indispensável na andrologia. A investigação da ecotextura testicular tem sido correlacionada à produção espermática, bem como com outros parâmetros. Além disso, o Doppler permite avaliações hemodinâmicas, contudo estudos utilizando essa técnica no trato reprodutor de cães são escassos. Assim, esse trabalho teve por objetivos avaliar a qualidade de espermatozoides caninos a fresco e verificar a correlação desta com o ultrassonografia testicular em cães sadios (Experimento 1), bem como mensurar os volumes testiculares esquerdo e direito, e o fluxo sanguíneo verificando se há diferença na irrigação entre o testículo esquerdo e direito e entre as regiões de cordão espermático e marginal ao testículo (Experimento 2). Para tanto, foram feitas coletas de sêmen de 20 cães sadios e ultrassonografia bidimensional para avaliação do volume testicular. O sêmen foi avaliado quanto à motilidade total, vigor, funcionalidade de membrana, integridade da membrana plasmática, viabilidade, morfologia espermática, a fragmentação do DNA pelo teste de dispersão da cromatina (teste SCD) e a atividade mitocondrial pelo teste 3,3'-diaminobenzidina (DAB). Foram obtidos os dados de Doppler (velocidade do pico sistólico-VPS, velocidade diastólica final-VDF, índices de pulsatilidade-IP e resistividade-IR) da artéria testicular em 3 diferentes regiões (supratesticular, marginal e intratesticular). Após a ultrassonografia, foram capturadas e analisadas 164 imagens para a mensuração de perímetro e da área a partir da quantificação de pixels proveniente das imagens de Doppler colorido dos testículos. Os parâmetros ultrassonográficos foram expressos de forma descritiva. Os demais parâmetros foram expressos na forma de média e desvio padrão. Diferenças foram consideradas significativas quando P < 0,05. Foi possível verificar correlação entre: IR supratesticular e viabilidade espermática (r = 0,31) e IP supratesticular e viabilidade (r = 0,32), VDF intratesticular e concentração espermática (r = 0,31), IR supratesticular e DAB II (r = 0,33). Correlação foi verificada entre VPS marginal e motilidade (r = -0,39), VPS marginal e vigor (r = -0,41) e IR intratesticular e concentração (r = -0,32). O volume testicular esquerdo foi significativamente maior (10,7 ± 2,6 cm3) do que o direito (9,9 ± 2,3 cm3, p<0,05). A quantidade de pixels ao Doppler colorido diferiu nas localizações, porém não foi encontrada diferença entre os dois testículos. A ultrassonografia bidimensional associada ao Doppler pode servir como uma ferramenta auxiliar em estudos andrológicos de cães. Além disso, o volume testicular esquerdo foi maior que o direito e a área e o perímetro na região do cordão espermático foram maiores que marginal ao testículo.

Ultrasonography has become indispensable in andrology. The investigation of testicular echotexture has been correlated with sperm production, as well as with other parameters. In addition, Doppler allows hemodynamic evaluations, however studies using this technique in the reproductive tract of dogs are scarce. The objective of this study was to evaluate the quality of fresh canine spermatozoa and verify their correlation with testicular ultrasonography in healthy dogs (Experiment 1), as well as to measure the left and right testicular volumes and blood flow checking for differences in the irrigation between the left and right testicles and between the regions of spermatic cord and marginal to the testis (Experiment 2). For this purpose, semen collections of 20 healthy dogs and B-mode ultrasonography were used to evaluate the testicular volume. Semen was evaluated for total motility, vigor, membrane functionality, plasma membrane integrity, viability, sperm morphology, DNA fragmentation by the chromatin dispersion test (SCD test) and mitochondrial activity by the 3,3'- diaminobenzidine (DAB). Doppler data (peak systolic velocity-PSV, end-diastolic velocity-EDV, pulsatility index-PI and resistivity index-RI) were obtained from the testicular artery in 3 different regions (supratesticular, marginal and intratesticular). After ultrasonography, 164 images were captured and analyzed for the perimeter and area measurement from the quantification of pixels from color Doppler images of the testis. Ultrasonographic parameters were expressed descriptively. The other parameters were expressed as mean and standard deviation. Differences were considered significant when P <0.05. It was possible to verify a correlation between supratesticularRI and sperm viability (r = 0.31) and supratesticular IP and viability (r = 0.32), intratesticular EDV and sperm concentration (r = 0.31), supratesticularRI and DAB II (r = 0.33). Correlation was verified between marginal PSV and motility (r = -0.39), marginal PSV and vigor (r = -0.41) and intratesticularRI and concentration (r = -0.32). The left testicular volume was significantly higher (10.7 ± 2.6 cm3) than the right one (9.9 ± 2.3 cm3). The number of colored Doppler pixels differed in the locations, but no difference was found between the two testicles.B-mode and Doppler ultrasonography could serve as an auxiliary tool in andrological studies of dogs. Finally, the left testicular volume was larger than the right one, the area and perimeter in the region of the spermatic cord were larger than the marginal region to the testis.

Sincronização folicular e vascularização do folículo dominante em novilhas mestiças tratadas com estradiol / Follicle synchronization and changes in vascularization of the dominantfollicle in crossbred heifers after estradiol treatment

Avaliou-se a sincronização folicular e vascularização na parede do folículo dominante (FD) após o tratamento com Cipionato (CE) ou Benzoato de estradiol (BE). No Experimento 1, 45 novilhas receberam implante de P4 (1,0g) e foram distribuídas em 3 grupos de acordo com éster de estradiol administrado pela via intramuscular: 1mL salina; 0,5mg CE ou 2,0mg BE. O diâmetro do FD e a emergência folicular (EF) foram monitorados por 5 dias. No experimento 2, D0 (dia 0): 30 novilhas receberam implante de P4 e 2,0mg BE; D8, retirada do implante e 0,5mg de prostaglandina (cloprostenol); D9: tratamentos: 1mL salina; 0,5mg CE ou 1,0mg BE. O diâmetro e a vascularização do FD foram monitorados do D8 ao D10. Os dados foram analisados por ANOVA ou Kruskal-Wallis, e as médias comparadas por Tukey (5%). No experimento 1, a EF ocorreu mais tarde (P 0,0013) no grupo BE (4,3±0,8 vs. 3,5±0,8d). No experimento 2, o fluxo sanguíneo do FD aumentou (P 0,001) 24h após o tratamento com BE. A taxa de ovulação foi semelhante (P>0,05) entre os grupos (80,0, 70,0 e 55,5%, BE, CE e salina). Conclui-se que nas concentrações utilizadas, o BE, no início do protocolo, retardou a EF e, no final do protocolo, promoveu uma melhor sincronia do FD demonstrada pela elevação do fluxo sanguíneo.(AU)

The study aimed to evaluate synchronization and blood flow of the dominant follicle (DF) after estradiol cypionate (EC) or benzoate(EB) treatment. In experiment 1, progesterone (P4) implants (1.0g) were inserted in 45 heifers, which were given 1mL saline,0.5mg EC or 2.0mg EB. The diameter of the DF and follicle emergence (FE) were recorded for 5 days. For experiment 2, 30 heiferswere given: D0 (day 0): P4 implant and 2.0mg EB; D8: implant removal and 0.5mg of prostaglandin (cloprostenol). On D9, theywere assigned in 1mL saline, 0.5mg EC or 1.0mg EB. From D8 to D10, the diameter and blood flow of the DF was monitored.Data were analyzed by ANOVA or Kruskal-Wallis test, and compared by Tukey (5%). In experiment 1, the FE occurred later(P<0.0013) in EB group (4.3±0.8 vs. 3.5±0.8d). In experiment 2, blood flow of the DF increased (P<0.001) 24h after EB treatment.The ovulation rate was similar (P>0.05) between groups (80.0, 70.0 and 55.5%, EB, EC and saline). The interpretation was that,in these concentrations, the EB, at the beginning, delayed FE and, at the end of the protocol, promoted a better synchrony of theDF, confirmed by the increase of the blood flow.(AU)

Sincronização folicular e vascularização do folículo dominante em novilhas mestiças tratadas com estradiol / Follicle synchronization and changes in vascularization of the dominantfollicle in crossbred heifers after estradiol treatment

Avaliou-se a sincronização folicular e vascularização na parede do folículo dominante (FD) após o tratamento com Cipionato (CE) ou Benzoato de estradiol (BE). No Experimento 1, 45 novilhas receberam implante de P4 (1,0g) e foram distribuídas em 3 grupos de acordo com éster de estradiol administrado pela via intramuscular: 1mL salina; 0,5mg CE ou 2,0mg BE. O diâmetro do FD e a emergência folicular (EF) foram monitorados por 5 dias. No experimento 2, D0 (dia 0): 30 novilhas receberam implante de P4 e 2,0mg BE; D8, retirada do implante e 0,5mg de prostaglandina (cloprostenol); D9: tratamentos: 1mL salina; 0,5mg CE ou 1,0mg BE. O diâmetro e a vascularização do FD foram monitorados do D8 ao D10. Os dados foram analisados por ANOVA ou Kruskal-Wallis, e as médias comparadas por Tukey (5%). No experimento 1, a EF ocorreu mais tarde (P 0,0013) no grupo BE (4,3±0,8 vs. 3,5±0,8d). No experimento 2, o fluxo sanguíneo do FD aumentou (P 0,001) 24h após o tratamento com BE. A taxa de ovulação foi semelhante (P>0,05) entre os grupos (80,0, 70,0 e 55,5%, BE, CE e salina). Conclui-se que nas concentrações utilizadas, o BE, no início do protocolo, retardou a EF e, no final do protocolo, promoveu uma melhor sincronia do FD demonstrada pela elevação do fluxo sanguíneo.

The study aimed to evaluate synchronization and blood flow of the dominant follicle (DF) after estradiol cypionate (EC) or benzoate(EB) treatment. In experiment 1, progesterone (P4) implants (1.0g) were inserted in 45 heifers, which were given 1mL saline,0.5mg EC or 2.0mg EB. The diameter of the DF and follicle emergence (FE) were recorded for 5 days. For experiment 2, 30 heiferswere given: D0 (day 0): P4 implant and 2.0mg EB; D8: implant removal and 0.5mg of prostaglandin (cloprostenol). On D9, theywere assigned in 1mL saline, 0.5mg EC or 1.0mg EB. From D8 to D10, the diameter and blood flow of the DF was monitored.Data were analyzed by ANOVA or Kruskal-Wallis test, and compared by Tukey (5%). In experiment 1, the FE occurred later(P0.05) between groups (80.0, 70.0 and 55.5%, EB, EC and saline). The interpretation was that,in these concentrations, the EB, at the beginning, delayed FE and, at the end of the protocol, promoted a better synchrony of theDF, confirmed by the increase of the blood flow.

Three-dimensional modeling of color Doppler images: a new approach to study follicular vascularization in cattle

Ovarian blood supply is directly related to follicle developmental potential and to oocyte quality, and color Doppler ultrasonography might be a valuable tool to predict in vitro fertilization outcomes. In most studies in large domestic animals, however, the evaluation of follicle blood flow is qualitative (presence or absence of color signal) or dependent on the analysis of a single image. The objective of the present study was to first describe the use of a three-dimensional (3D) modeling of color Doppler images for a quantitative assessment of vascularization in bovine ovarian follicles. Follicular wave emergence was synchronized in Holstein and Gir heifers (n = 20), and follicular dynamics were assessed every 12 h using a color Doppler ultrasound device. The recorded cine-loop of the dominant follicle was decomposed into frames and medical image processing software was used to isolate the Doppler signal, generate the 3D model and calculate the volume of vascularization. In experiment 1, the model was validated by comparing the expected and calculated volumes and was used to predict possible variations in the results of the 2D approach. In experiment 2, vascularization was analyzed during follicular development. In both breeds, the volume of vascularization increased after follicle deviation and was positively correlated (P < 0.05) to follicular diameter (r = 0.65 and 0.54 for Holstein and Gir heifers, respectively). Spatial analysis of the three-dimensional model showed an uneven distribution of vascularization in the follicular wall, with a more intense blood flow being detected in the basal (nearest the ovarian hilus) and lateral regions of the dominant follicles. These results demonstrate the potential of this technique as a new tool for in vivo studies of ovarian physiology in large animals.

Three-dimensional modeling of color Doppler images: a new approach to study follicular vascularization in cattle

Ovarian blood supply is directly related to follicle developmental potential and to oocyte quality, and color Doppler ultrasonography might be a valuable tool to predict in vitro fertilization outcomes. In most studies in large domestic animals, however, the evaluation of follicle blood flow is qualitative (presence or absence of color signal) or dependent on the analysis of a single image. The objective of the present study was to first describe the use of a three-dimensional (3D) modeling of color Doppler images for a quantitative assessment of vascularization in bovine ovarian follicles. Follicular wave emergence was synchronized in Holstein and Gir heifers (n = 20), and follicular dynamics were assessed every 12 h using a color Doppler ultrasound device. The recorded cine-loop of the dominant follicle was decomposed into frames and medical image processing software was used to isolate the Doppler signal, generate the 3D model and calculate the volume of vascularization. In experiment 1, the model was validated by comparing the expected and calculated volumes and was used to predict possible variations in the results of the 2D approach. In experiment 2, vascularization was analyzed during follicular development. In both breeds, the volume of vascularization increased after follicle deviation and was positively correlated (P < 0.05) to follicular diameter (r = 0.65 and 0.54 for Holstein and Gir heifers, respectively). Spatial analysis of the three-dimensional model showed an uneven distribution of vascularization in the follicular wall, with a more intense blood flow being detected in the basal (nearest the ovarian hilus) and lateral regions of the dominant follicles. These results demonstrate the potential of this technique as a new tool for in vivo studies of ovarian physiology in large animals.(AU)