O presente estudo teve como objetivo avaliar a capacidade crioprotetora das lipoproteínas de baixa densidade (LDL) presentes no plasma de gema de ovo, adicionado ao trihidroxiaminometano (TRIS) para congelar sêmen ovino. Trinta e seis ejaculados foram coletados para formar 12 "pool". Cada alíquota de sêmen foi diluída em TRIS-gema de ovo (TRISG) ou TRIS- plasma de gema de ovo (TRISP) antes de congelar o sêmen. Para a obtenção do plasma da gema de ovo, foi utilizado o método de ultracentrifugação. Após o descongelamento, não houve diferença entre os dois extensores em relação aos parâmetros seminais (motilidade, viabilidade, membrana acrossômica e plasma). No entanto, no Teste de Termo Resistência Lenta (TTRL - 4h/38°C), o sêmen congelado com TRISP resultou no aumento do número de espermatozoides com acrossoma intacto (P<0,032). Conclui-se que o diluente TRISP é uma alternativa para criopreservação do sêmen de carneiros, pois permite uma melhora da característica seminal em relação ao diluente TRIS gema, mas sem a necessidade do processo de purificação das LDL.

The present study aimed to evaluate the cryoprotectant low-density lipoprotein (LDL) present in the plasma of egg yolk added to the extender trihidroxiaminometano (TRIS) for freezing ram semen. Thirty-six ejaculates were collected to form 12 pool. Each aliquot of semen was diluted in TRIS-egg yolk (TRISG) or TRIS-egg yolk plasma (TRISP) before freezing the semen. The plasma of egg yolk was obtained by ultracentrifugation. After thawing, no difference was detected between the two extenders in relation to seminal parameters (motility, viability, plasma membrane and acrosome). However, in the thermal resistance slow test (4h in a water bath at 38°C), the semen frozen with TRISP resulted in higher number of sperm with intact acrosome than those with TRISG (P<0.032). It was concluded that the TRISP extender is an alternative for cryopreservation of ram semen, once it improves the semen characteristics in comparison to TRISG, avoiding the purification process of LDL.

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 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.

Para caracterização Geográfica da involução uterina e reinício da atividade ovariana, o puerpério de 15 vacas da raça charolesa foi acompanhado pela ultra-sonografia a partir do 8° dia, com intervalo de 3 dias, até o 40° dia pós-parto. Utilizou-se um aparelho de ultra-som Pie Medical Inc., mod. 450 com transdutor de 5MHz, arranjo linear e uma impressora. A involução completa do útero foi detectada aos 28,12±1,55 dias nas vacas com parto eutócico e aos 32,57±1,13 dias nas vacas com parto distócico, e o conteúdo uterino não foi mais visualizado aos 18,87±1,12 dias e 25,28±1,38 dias, respectivamente, após o parto. O curso do puerpério foi testado por regressão linear e quadrática, quando observou-se uma diferença altamente significativa entre partos eutócico e distócico, na involução dos cornos uterinos (p < 0,0001) e do cérvix (p < 0,01). No 10° dia foram detectados folículos grandes nos ovários e no 13° dia pós-parto, já ocorreu ovulação, porém, sem manifestação estral. O monitoramento da involução uterina e do conteúdo uterino durante o puerpério, assim como do reinício da atividade ovariana é viável através da ultra-sonografia.

The aim of this study was to investigate uterus involution and ovarian activity by ultrasonography. The puerperium of fifteen charolais cows was observed from the 8th to 40th day, with interval of 3 days. A Pie Medicai Inc. Scanner Mod. 450 with a 5MHz linear array transducer and a printer were used for ecographic purposes. The uterus complete involution, was detected on the 28.12±1.55 days in the cows with normal parturition and on the 32.57±1.13 days in the cows with dystocia and the lochia was not visualized on the 18.87±1.12 days and 25.28±1.13 day respectively postpartum. The puerperium period was tested by linear and quadratic regression. A high significance was observed, between normal and dystocic parturition on the uterino horn involution (p < 0.0001) and the cérvix (p < 0.01). On the 10th day, great follicles was detected and on the 13th day ovulation was observed without estrous manifestation. The correct monitoration of uterus involution, as well as the lochia and resumption of ovarian function, during the puerperium, is feasible through ultrasonography.

RESUMO O objetivo do trabalho foi de estudar o desenvolvimento embrionário e revelar quando a prenhez pode ser detectada em bovinos. Constituindo dois grupos, 142 vacas foram submetidas a exames ecográficos para diagnóstico de gestação. Utilizou-se um aparelho Pie Medical Inc., Mod. 450 com transdutor de 5MHz, arranjo linear e uma impressora. No primeiro grupo, constituído de 12 vacas charolesas foram estudadas algumas características da anatomia fetal entre o 10° e o 50° dia. Estruturas foram detectadas na seguinte ordem e tempo (dias): vesícula embrionária (18,0 ± 0,7); embrião (24,1 ± 0,5); batimentos cardíacos (26,2 ± 0,6); âmnio (30,7 ± 0,7); membros (32,7 ± 0,6); vértebras (40,2 ± 0,7) e movimentos fetais (45,6 ± 0,5). No segundo grupo, composto de 130 vacas cruza charolesa, foi observado o desenvolvimento embrionário do 23° até o 50° dia de gestação. Neste período a vesícula embrionária atingiu um diâmetro de 46,4mm, com crescimento diário de 1,38mm; enquanto o comprimento (cabeça-anca) do embrião atingiu 36,4mm, com aumento diário de 1,15mm (P<0,0001). O diagnóstico precoce da gestação, e o seu monitoramento através da ultra-sonografia é possível a partir do 18° dia pós-serviço.

SUMMARY The aim of this study was to investigate the embryonic development and the age of the pregnancy, in which may firstly be detected by ultrasound. One hundred and forty two cows, performing two groups were submitted to echographic examination for pregnancy diagnosis. A Pie Medical Inc. scanner Mod. 450 with a 5MHz linear array transducer and a printer were used for echographic purposes. In the first group constituted of 12 charolais cows were studied some characteristics of the fetal anatomy from the 10th to the 50th day. The first detection of the subsequent structures was made in the following days: embryonic vesicle (18.0 ± 0.7); embryo proper (24.1 ± 0.5); heartbeat (26.2 ± 0.6); amnion (30.7 ± 0.7); limbs (32.7 ± 0.6); vertebres (40.2 ± 0.7); fetal movements(45.6 ± 0.5). In the second group constituted of 130 cross bred charolais cows the embryonic development from the 23rd to the 50th day of gestation was observed. In this period the embryonic vesicle reached a diameter of 46.4mm with a daily growth of 38mm and the embryo, a length (crown-rump) of 36.4rnm with a daily increase of 1.15mm (P<0.0001). The eariy pregnancy diagnosis as well as the monitoring of gestation, is feasible through uttrasonography.