Viable offspring after successful non-surgical embryo transfer in goats / Nascimento de fetos viáveis após transferência de embriões não-cirúrgica em caprinos

O objetivo do presente estudo foi avaliar a viabilidade da técnica de transferência não cirúrgica em cabras. Quatro cabras não-lactantes pluríparas da raça Toggenburg foram utilizadas como receptoras de embriões, sendo que duas receberam um embriões e duas receberam dois embriões coletados não cirurgicamente cabras doadoras. Os corpos lúteos das receptoras foram detectados um dia antes da transferência de embriões por ultrassonografia transretal. Uma seringa de 5mL contendo 2mL de meio holding foi acoplada em um cateter tomcat, no qual os embriões foram aspirados em uma coluna central a duas outras colunas. Um espéculo Colin número 2 foi inserido na vulva e na vagina, e com o uso de uma fonte de luz, a cerviz foi localizada e imobilizada com uma pinça de Allis. Um cateter uretral número seis acoplado a um mandril e lubrificado com meio PBS foi inserido na cérvix, e assim os aneis cervicais foram gradualmente transpostos. Após perder a resistência, o cateter uretral foi movido lateralmente para o corno uterino desejado. O mandril e a pinça de Allis foram retirados e o conjunto seringa e tomcat foi acoplado ao cateter uretral e o conteúdo injetado no corno uterino ipsilateral ao corpo lúteo com posterior retirada do cateter. Cabras que ovularam em apenas um ovário foram usadas para testar a eficiência da deposição do embrião. O tempo gasto entre a inserção do espéculo e a sua remoção foi inferior a três minutos. O tempo para transpor a cérvix foi inferior a um minuto. A ultrassonografia revelou a deposição de líquido no corno desejado. Receptoras que receberam dois embriões tornaram-se gestantes e pariram três crias. Estes primeiros resultados encorajam a técnica e demonstram que a transferência de embriões em caprinos pode ser feita totalmente por procedimentos não cirúrgicos.(AU)

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)

Doppler ultrasonography as a tool for ovarian management

Doppler ultrasonography allows the characterization and measurement of blood flow, and can be used to indirectly make inference regarding the functionality of different organs, including the ovaries. Several studies highlighted the importance of an adequate blood flow for follicle development and acquisition of ovulatory potential, and for progesterone secretion by the corpus luteum. Due to some particularities of the ovarian vascular anatomy, however, different strategies had to be developed to measure the blood flow detected by Doppler imaging. Some of these approaches were successful to characterize the patterns of blood flow throughout the estrous cycle, pregnancy, and early postpartum, but require post acquisition image processing and do not allow real time decisions to be taken. The subjective evaluation of blood flow has been alternatively used in field conditions aiming to early detect non pregnant animals, select embryo recipients, or predict artificial insemination and in vitro fertilization outcomes. In summary, color Doppler imaging provides important information about the function of corpus luteum and follicles, supporting clinical diagnoses and management decisions. Nonetheless, the adoption of Doppler ultrasonography as a routine exam, instead of a limited use in an individual basis, requires further development of feasible blood flow evaluation procedures and the establishment of reference values.

Doppler ultrasonography as a tool for ovarian management

Doppler ultrasonography allows the characterization and measurement of blood flow, and can be used to indirectly make inference regarding the functionality of different organs, including the ovaries. Several studies highlighted the importance of an adequate blood flow for follicle development and acquisition of ovulatory potential, and for progesterone secretion by the corpus luteum. Due to some particularities of the ovarian vascular anatomy, however, different strategies had to be developed to measure the blood flow detected by Doppler imaging. Some of these approaches were successful to characterize the patterns of blood flow throughout the estrous cycle, pregnancy, and early postpartum, but require post acquisition image processing and do not allow real time decisions to be taken. The subjective evaluation of blood flow has been alternatively used in field conditions aiming to early detect non pregnant animals, select embryo recipients, or predict artificial insemination and in vitro fertilization outcomes. In summary, color Doppler imaging provides important information about the function of corpus luteum and follicles, supporting clinical diagnoses and management decisions. Nonetheless, the adoption of Doppler ultrasonography as a routine exam, instead of a limited use in an individual basis, requires further development of feasible blood flow evaluation procedures and the establishment of reference values.(AU)

Features and perspectives of the Brazilian in vitro embryo industry

In the last decade , in vitro fertilization emerged as an alternative to superovulation and has become the technique of choice for bovine embryo production, especially in zebu breeds. The recent growth in the commercial use of in vitro technologies in the Brazilian embryo industry is reviewed here in , highlighting the features and trends during different periods , as well as future challenges and perspectives . The data presented here w ere provided by the Statistics Committee of the Brazilian Embryo Techno logy Society and include reports from breeders associations, commercial IVF companies and ET practitioners . Three different periods were characterized for the use of IVF technologies in the Brazilian embryo industry: 1) the early years (1999 - 2003), when IV F growth was driven by the growing demand from the embryo market, although the technology was still labeled as elit ist ; 2) a period of exponential growth (2003 - 2006), when IVF overc a me conventional ET as the technique of choice for embryo production; and 3 ) a later period , when total numbers tend ed to stabilize but IVF started to increase in importance in dairy breeds. The whole picture shows IVF as an interesting example of innovation, since the development of these new embryo technologies provided new pro ducts, processes and possibilities to satisfy demands and remarkably change the scenario of the Brazilian embryo industry.

Features and perspectives of the Brazilian in vitro embryo industry

In the last decade , in vitro fertilization emerged as an alternative to superovulation and has become the technique of choice for bovine embryo production, especially in zebu breeds. The recent growth in the commercial use of in vitro technologies in the Brazilian embryo industry is reviewed here in , highlighting the features and trends during different periods , as well as future challenges and perspectives . The data presented here w ere provided by the Statistics Committee of the Brazilian Embryo Techno logy Society and include reports from breeders associations, commercial IVF companies and ET practitioners . Three different periods were characterized for the use of IVF technologies in the Brazilian embryo industry: 1) the early years (1999 - 2003), when IV F growth was driven by the growing demand from the embryo market, although the technology was still labeled as elit ist ; 2) a period of exponential growth (2003 - 2006), when IVF overc a me conventional ET as the technique of choice for embryo production; and 3 ) a later period , when total numbers tend ed to stabilize but IVF started to increase in importance in dairy breeds. The whole picture shows IVF as an interesting example of innovation, since the development of these new embryo technologies provided new pro ducts, processes and possibilities to satisfy demands and remarkably change the scenario of the Brazilian embryo industry.(AU)

Efeito do nível de uréia na dieta sobre o desempenho, a qualidade e o estádio de desenvolvimento embrionário em cabras Alpinas / Effect of the dietary urea level on performance, quality and embryonic development stage on Alpine goats

Utilizaram-se 22 cabras da raça Alpina, distribuídas aleatoriamente em quatro tratamentos (T): as cabras do T1 (n=5) formaram o grupo-controle; as do T2 (n=7) receberam 0,73 por cento de uréia na matéria seca da dieta; as do T3 (n=4) receberam 1,46 por cento de uréia; e as do T4 (n=6), 2,24 por cento de uréia. As cabras foram superovuladas e os embriões, coletados entre sete e oito dias após a primeira monta, foram avaliados quanto à qualidade e ao estádio de desenvolvimento. Amostras de sangue para dosagem dos teores de uréia e glicose foram coletadas nos dias do estro e da coleta de embriões. Houve efeito linear crescente do nível de uréia nas dietas sobre o consumo de MS (kg/dia) e de proteína bruta (kg/dia). O peso das cabras não diferiu (P>0,05) entre os tratamentos nem entre as semanas experimentais. Dezoito cabras (81,8 por cento) manifestaram estro após a sincronização. A duração do estro e o intervalo da remoção da esponja ao início do estro não foram influenciados (P>0,05) pelos tratamentos. Quatorze cabras (77,8 por cento) responderam à superovulação. O número de estruturas e de embriões coletados não diferiu (P>0,05) entre os tratamentos. O número (Y= 10,90 - 11,64NS U + 4,93§U²; R² = 0,67; P<0,10) e a percentagem (Y= 94,08 - 39,59NS U + 18,16ªU²; R² = 0,94; P<0,07) de embriões viáveis, e o número (Y= 10,83- 12,18NS U + 5,02mU²; R² = 0,78; P<0,08) e a percentagem (Y= 94,83- 52,31NS U + 21,56*U²; R² = 0,90; P<0,05) de embriões excelentes e bons apresentaram comportamento quadrático em função do nível de uréia nas dietas. Os teores de uréia e glicose no plasma não foram influenciados (P>0,05) pelos tratamentos. A uréia pode ser fornecida no nível de 2,24 por cento na MS da dieta de cabras não lactantes(AU)

Twenty-two Alpine goats were allocated at random into four treatments: 0.0 percent (T1 - control, n=5); 0.73 percent (T2, n=7); 1.46 percent (T3, n=4) or 2.24 percent (T4, n=6) of urea in the dry matter (DM) of the diet. Embryos collected from 7 to 8 days after mating of superovulated goat were evaluated by quality and development stage. Blood samples for urea and glucose analyses were collected at estrus and at embryos collection day. The DM (kg/day) and crude protein (kg/day) intake increased linearly in function of dietary urea level. Goat body weights were not affected by treatments out experimental weeks (P>0.05). Eighteen goats (81.8 percent) came in estrus after the synchronization. The estrus length and the interval from sponge removal to the beginning of estrus were not affected (P>0.05) by treatments. Fourteen goats (77.8 percent) were responsive to superovulation protocol. The levels of urea (treatments) did not affect structures and embryo numbers (P>0.05). Number (Y= 10.90 - 11.64NS U + 4.93§U²; R²= 0.67; P<0.10) and percentage (Y= 94.08 - 39.59NS U + 18.16ªU²; R²= 0.94; P<0.07) of viable embryos, and number (Y= 10.83- 12.18NS U + 5.02mU²; R²= 0.78; P<0.08) and the percentage (Y= 94.83- 52.31NS U + 21.56*U²; R²= 0.90; P<0.05) of excellent and good embryos were quadraticaly effected by urea dietary level. The treatments did not affect plasma urea and glucose levels (P>0.05). Diets for no nursing goats can be supplied by urea at 2.24 percent of DM(AU)