Impact of ethanol and heat stress-dependent effect of ultra-diluted Arnica montana 6 cH on in vitro embryo production in cattle.

This study evaluated the effect of adding ultra-diluted and dynamized Arnica montana 6 cH, and its vehicle (0.3% ethanol) to the in vitro maturation (IVM) medium, in the absence (experiment 1) or presence (experiment 2) of heat stress (HS), on bovine oocyte maturation and in vitro embryo production (IVEP). In experiment 1 (n = 902 cumulus oocyte complexes, COCs), the treatments were 1) IVM medium (Control treatment), 2) IVM medium + 0.3% ethanol, and 3) IVM medium + Arnica montana 6 cH. In experiment 2 (n = 1064 COCs), the treatments were 1) IVM medium without HS, 2) IVM medium under HS, 3) IVM medium + ethanol under HS, and 4) IVM medium + Arnica montana under HS. In the absence of HS (experiment 1), the addition of Arnica montana to the IVM medium had a deleterious effect on the IVEP (cleavage and blastocyst rates) and the total cell number/blastocysts. On the other hand, ethanol (0.3%) increased IVEP in relation to the Control and Arnica montana treatments. However, in the presence of HS during IVM (experiment 2), the addition of ethanol or Arnica montana increased IVEP when compared to the HS treatment alone, and the Arnica montana treatment resulted in greater total cell number/blastocysts compared to the other treatments. In conclusion, this study showed for the first time that the negative or positive effect of Arnica montana 6 cH on IVEP depends on the culture condition (i.e., absence or presence of HS during IVM). On the other hand, ethanol showed beneficial and consistent results on IVEP regardless of exposure to HS.

Ovarian follicular dynamic and plasma progesterone concentration in Alpine goats on the breeding season / Dinâmica folicular ovariana e concentração plasmática de progesterona em cabras Alpinas durante a estação reprodutiva

Os objetivos deste estudo foram relatar a dinâmica folicular ovariana e a concentração plasmática de progesterona durante ciclos estrais de duração irregular em cabras da raça Alpina. Vinte e nove cabras tiveram sua atividade ovariana monitorada diariamente por ultrassonografia transretal durante um, dois ou três períodos interovulatórios consecutivos. Amostras de sangue foram coletadas para análise da concentração plasmática de progesterona. Dos 47 ciclos avaliados, 28 (59,57%) foram de duração normal (17 a 25 dias), sete (14,89%) de curta duração (<17 dias) e 12 (25,53%) de longa duração (>25 dias). Os ciclos estrais de curta duração tiveram 6,14±0,69 dias e uma onda folicular que emergiu no dia 0,43±1,13. Os ciclos estrais de longa duração tiveram entre 26 e 79 dias, com duas a nove ondas foliculares. Os ciclos estrais de curta duração ocorreram durante a estação reprodutiva e foram associados à regressão prematura do corpo lúteo (CL). Os ciclos estrais de longa duração ocorreram na transição entre o anestro e a estação reprodutiva e foram associados principalmente à persistência do CL ou à fase folicular prolongada.(AU)

Influência da condição corporal ao parto no balanço energético e desempenho reprodutivo de cabras leiteiras no pós-parto / Influence of body condition at calving on energy balance and reproductive performance of dairy goats in the postpartum

O estudo teve como objetivo avaliar a influência da condição corporal (CC) ao parto no balanço energético (BE) e o desempenho reprodutivo de cabras Alpinas no pós-parto. Foram utilizadas 68 cabras distribuídas em três grupos (G), sendo: G1- cabras com baixa CC (CC entre 1,5 e 2,5); G2: cabras com moderada CC (entre 2,75 e 3,5) e G3: cabras com alta CC (entre 3,75 e 5,0). Os animais receberam dieta (silagem de milho e concentrado, com 18% de proteína bruta e 1,7Mcal/kg de matéria seca de energia líquida) ad libitum. As avaliações foram feitas nas oito primeiras semanas de lactação, para determinação do BE, do intervalo do parto à primeira ovulação e ao primeiro estro e da concentração plasmática de progesterona. Os dados foram analisados por análise de variância a 5% de probabilidade. Não houve efeito da CC ao parto sobre o BE dos animais. Todas as cabras apresentaram BE negativo ao parto, com mudança para BE positivo aos 51, 58 e 64 dias pós-parto, respectivamente. Não houve diferença na concentração plasmática de progesterona nos três grupos, sendo caracterizada função luteal (concentração ≥1ng/dL) em apenas 5,9% dos animais avaliados. O intervalo do parto à primeira ovulação foi de 46 dias. Apenas 4,4% das cabras exibiram estro. Cabras leiteiras de média produção, entre 2,5 e 3,0kg de leite/dia, entram em BE negativo ao parto, independentemente da CC apresentada, influenciando negativamente o reinício da atividade ovariana no pós-parto.(AU)

The concentration of progesterone in the blood was used to study the effect of body condition score (BCS) on the post-partum ovarian activity of dairy goats. Sixty-eight female goats were distributed between three treatments. Treatment 1: goats with BCS between 1.00 and 2.75; Treatment 2: goats with BCS between 2.75 and 3.50; and Treatment 3: goats with BCS between 3.50 and 5.00. The goats had the blood collected immediately after birth, and from that time up to the eighth week post-partum at three day intervals. The progesterone analysis on the blood was used to determine the interval between the birth and the first ovulation. The females were teasing two times per day for estrus detection and determination of the time interval from birth to first estrus. No significant difference was found on the progesterone concentration between treatments. The luteal functionality was characterized in only 5.9% of goats, with a concentration higher than 1ng/mL. The period from birth to first ovulation was 46 days. The detectable estrus was found in only 4.4% of goats. The BCS at birth did not influence the recovery of ovarian activity of dairy goats.(AU)

Influência do Hormônio do Crescimento na concentração de testosterona plasmática e nas características seminais de touros jovens e adultos da raça Nelore / Influence of Growth Hormone on plasma testosterone concentration and seminal characteristics of young and adult Nellore bulls

Estudou-se o efeito do Hormônio do Crescimento bovino (bGH) sobre os parâmetros seminais e a concentração sérica de testosterona de touros da raça Nelore. Dezesseis touros foram distribuídos em um delineamento fatorial 2 x 2 (duas idades e dois níveis de r-bST), com quatro animais em cada tratamento. As aplicações de r-bST foram realizadas a cada 14 dias, totalizando nove aplicações por animal, em um período experimental de 120 dias. As coletas de sêmen foram realizadas a cada 15 dias e, para determinar as concentrações de testosterona, foram realizadas coletas de sangue a cada quatro horas, num total de 24 horas, e a cada 30 dias a partir da primeira aplicação de r-bST. O sêmen dos touros adultos tratados com r-bST apresentaram maior motilidade e vigor (P<0,05) em relação aos animais controles (79,70±11,56% vs 64,06±23,65%) e (3,80±0,88 vs 2,92±1,25), respectivamente; entretanto, as demais características seminais não foram influenciadas (P>0,05) pelo tratamento com r-bST. Os aspectos físicos do sêmen dos touros jovens não foram afetados (P>0,05) pelo tratamento com r-bST. Entretanto o tratamento com r-bST diminuiu os defeitos morfológicos menores (delgado, gigante normal, pequeno normal, globoso, cabeça isolada normal, abaxial, cauda dobrada e enrolada levemente e gota distal) em relação aos jovens não tratados (P<0,05). As concentrações séricas de testosterona foram influenciadas (P<0,05) pelo tratamento, aos 120 dias após a primeira aplicação do r-bST, e apresentaram tendência de três picos no período de 24 horas.

The aim of this trial was to study the effect of Growth Hormone (GH) on the seminal parameters and testosterone profile from Nellore bulls. Sixteen bulls were allocated in a 2 x 2 factorial arrangement (two ages and two r-bST levels), with four animals per treatment. The r-bST was injected every 14 days, with a total of nine injections per animal, during the 120 days of the experimental period. The semen collections were done every 15 days and blood samples were collected in four hour intervals for 24 hours, and in 30 day intervals from the first r-bST injection for testosterone profile. The semen of adult bulls treated with r-bST showed greater MOT and VIG (P<0.05) in relation to the control (79.70±11.56% vs 64.06±23.65%) and (3.80±0.88 vs 2.92±1.25) respectively; however, the other evaluated seminal parameters were not affected (P>0.05) by the r-bST treatment. The physical measurements of the semen of young animals was also unaffected (P>0.05) by r-bST injection. However, the treatment with r-bST decreased the number of minor morphologic defects (narrow head, giant head, small normal head, round head, free normal head, abaxial implantation, simple bent tail and distal droplet) compared to untreated young bulls (P<0.05). The serum testosterone concentration was influenced (P<0.05) by treatment, at 120 days after the first injection of r-bST and they showed a tendency of three picks in a 24 hour period of sampling.

Effects of prostaglandin administration 10 days apart on reproductive parameters of cyclic dairy nulliparous goats / Efeitos da aplicação de prostaglandinas intervaladas de 10 dias sobre características reprodutivas de cabras leiteiras nulíparas cíclicas

This study reported the effects of prostaglandin (PGF2a) administration 10 days apart on reproductive parameters of cyclic artificial inseminated (AI) nulliparous Alpine (n=9) and Saanen (n=9) goats. Animals received two doses of 22.5mg PGF2a 10 days apart. After 1st and 2nd PGF2a administrations, estrus was monitored at 12 h intervals, with a buck teaser. Plasma progesterone concentration (ng/mL) was determined from blood sampled on day 0 (1st PGF2a) and the following 5, 10 (2nd PGF2a), 15, 20, 25 and 30 days. After the onset of the second estrus, females were transrectally (5 MHz probe) scanned at 4 hour intervals until at least 8h after ovulation. Pregnancy was checked through transrectal ultrasound on days 20, 25, 30, 35 and 90 after insemination. All parameters studied did not differ between breeds (P>0.05). Estrous response and interval to estrus, respectively, after 1st (78.9% and 50.6±17.2h) and 2nd PGF2a (88.9% and 50.0±14.8h) administration did not differ (P>0.05). Overall animals ovulating (100.0%), interval to ovulation after 2nd PGF2a (64.5±19.5h) and after estrous onset (18.0±9.1h), ovulation rate (1.3±0.5), diameter of ovulatory follicle (8.1±1.1mm) were recorded. Embryo loss occurred before day 30 of pregnancy. Estrus can be efficiently synchronized in nulliparous Alpine and Saanen goats with two doses of prostaglandin 10 days apart.

Relataram-se os efeitos da aplicação de prostaglandina sobre características reprodutivas de cabras leiteiras nulíparas cíclicas. Cabras Alpinas (n=9) e Saanen (n=9) receberam duas doses de 22,5mg PGF2a com 10 dias de intervalo. A progesterona plasmática (ng/mL) foi determinada a partir de amostras de sangue coletadas nos dias 0 (primeira dose), 5, 10 (segunda dose), 15, 20, 25 e 30. Após início do segundo estro, as fêmeas foram monitoradas por ultrassonografia transretal a cada quatro horas até oito horas após a ovulação. A gestação foi verificada por ultrassonografia transretal nos dias 20, 25, 30, 35 e 90 após a segunda dose. As características estudadas foram semelhantes entre as raças (P>0,05). Animais em estro e o intervalo parto-estro de, respectivamente, 78,9% e 50,6±17,2h e 88,9% e 50,0±14,8h após a primeira e segunda administrações de prostaglandina, não diferiram (P>0,05). Todas as cabras ovularam e registraram-se valores do intervalo parto-ovulação após a segunda aplicação de prostaglandina de 64,5±19,5h e após início do estro de 18,0±9,1h, a taxa de ovulação de 1,3±0,5 e diâmetro do folículo ovulatório de 8,1±1,1mm. Perda embrionária ocorreu antes de 30 dias de gestação. O estro pode ser eficientemente sincronizado em cabras leiteiras núliparas com duas doses de prostaglandina intervaladas de 10 dias.

Autoclaved, previously used intravaginal progesterone devices induces estrus and ovulation in anestrous Toggenburg goats.

Intravaginal progesterone devices are used worldwide for estrus induction in goats. Reused devices are able to induce estrus; however, this can be a health risk within a flock. The objective was to compare new and previously used (and autoclaved) progesterone-releasing intravaginal devices for induction of estrus and ovulation in seasonally anestrous Toggenburg goats. Anestrous goats (n=42) received new intravaginal devices containing 0.3g progesterone (CONTROL), or similar devices previously used for either 6 (USED6) or 12d (USED12) and subsequently autoclaved. All goats received 5mg dinoprost at device insertion and 200 IU eCG 5d later, and all devices were removed after 6d. After device removal, estrus was monitored and females displaying signs of estrus were mated by fertile bucks. Transrectal ovarian ultrasonography was performed after device removal until detection of ovulation. Blood samples were collected for determination of plasma progesterone concentration at different times. There was no difference (P>0.05) among groups CONTROL, USED6 or USED12 for: estrus response (87, 100 or 100%, respectively); duration of estrus (32.3±2.3, 25.2±3.4 or 27.3±4.1h); ovulation rate (100, 88 or 100%); number of ovulations (1.5±0.2, 1.9±0.3 or 1.7±0.3); and pregnancy rate (60, 58 or 67%). Plasma progesterone (P4) concentrations were greater (P<0.05) in CONTROL than in USED6-treated and USED12-treated goats (7.2±1.2, 4.7±0.7 and 4.3±0.6 ng/mL, respectively) at 6h after device insertion; these differences were maintained until 4d after device insertion (3.4±0.4, 2.3±0.2, and 2.5±0.2 ng/mL). Overall, plasma progesterone concentrations were greater (P<0.05) in nulliparous than in lactating goats (3.1±0.8 compared to 2.4±0.6 ng/mL, respectively). In conclusion, autoclaved, previously used intravaginal progesterone-releasing devices resulted in significant lesser plasma progesterone concentrations than new devices, but were similarly effective in inducing estrus and ovulation in anestrous goats.

Reproductive parameters of Mangalarga Marchador mares in a commercial embryo transfer programme.

The objective of this study is to evaluate the reproductive efficiency in donors and recipient Mangalarga Marchador mares in commercial programmes of embryo transfer (ET) and the effects of some reproductive characteristics and ET methodology on conception rates in the recipient mares. A total of 1140 flushing procedures were performed and 830 embryos (72.8%) were recovered. There were no differences between the rates of embryonic recovery in the different breeding seasons (p > 0.05) and 92.8% of the recovered embryos were 8-9 days old. There was no difference in the embryonic recovery regarding the collection order from the first to the ninth embryo collection along the breeding season, as well as among mares inseminated during the foal heat or subsequent cycles (p > 0.05). Pregnancy rates observed in the total period of all reproductive seasons at 15, 30, 45 and 60 days of pregnancy were 73.4, 69.9, 66.7 and 64.5%, respectively. Differences in pregnancy rate and early embryonic loss rates were not observed between embryos transferred immediately after collection (66.8% and 13.5%) and embryos transported at room temperature for periods of < 1 h (62.9% and 14.4%; p > 0.05). Pregnancy rates were higher when the interval between ovulations of donor and recipient mares remained between -3 and -2 days (p < 0.05), and the lowest rates were observed for intervals of -6 days (p < 0.05) with intermediary values for intervals of -1, 0 and +1 (p > 0.05). Embryonic loss rates, however, did not differ between intervals of ovulation's synchronism between donor and recipient mares (p > 0.05). This flexibilization in the ovulatory synchronism between donor and recipient mares optimizes the use of recipient mares, thus reducing costs and facilitating management of horse breeding farms.

Efeito de fontes de óleo e níveis de suplementação de vitamina E na ração sobre as características físicas e morfológicas do sêmen in natura de suínos / Effect of oil sources and vitamin E supplementation in the diet on physical and morphological characteristics of fresh boar semen

Avaliou-se o efeito da adição de diferentes fontes de óleo e níveis de suplementação de vitamina E na ração sobre as características do sêmen in natura de suínos reprodutores. Foram utilizados 24 reprodutores Dalboar 85, com idades entre 12 e 18 meses, distribuídos em delineamento inteiramente ao acaso, em arranjo fatorial 2 x 3, com duas fontes de óleo, soja e salmão, e três níveis de antioxidantes, 150, 300 e 450mg de vitamina E/kg. Volume, motilidade espermática total, teste hiposmótico, porcentagem de espermatozoides vivos e morfologia espermática não diferiram (P>0,05) entre os tratamentos. Óleo de salmão (P<0,05) melhorou o vigor espermático. A inclusão de vitamina E na ração melhorou (P<0,05) a concentração espermática, e não foi observada diferença entre as fontes de óleo (P>0,05). Os animais tratados com óleo de salmão apresentaram menor (P<0,05) concentração de antioxidantes totais no sêmen do que os tratados com óleo de soja. Observou-se efeito linear da vitamina E sobre a concentração de antioxidantes totais (P<0,05). A fonte de óleo de salmão da ração melhora o vigor espermático e a concentração de antioxidantes totais no sêmen.

The addition of oil sources and dietary vitamin E supplementation was evaluated on the characteristics of fresh boar sperm. Twenty-four mature Dalboar 85 boars of proven fertility and in routine semen production for artificial insemination were randomly distributed in a factorial arrangement 2 X 3, with two oil sources, soy and salmon, and three antioxidant levels: 150, 300, and 450mg/kg of vitamin E. Volume, total motile sperm, hyposmotic swelling test, percentage of live cell, and morphology did not differ (P<0.05) between the animals from the treatments. Salmon oil improved (P<0.05) sperm vigor. The vitamin E added to the diet improved (P<0.05) the sperm concentration, and there was no difference between the oil sources (P>0.05). Salmon oil treatment showed the lowest (P<0.05) concentration of total antioxidants in the semen. Vitamin E and concentration of total antioxidant showed a linear effect (P<0.05). The semen vigor and the concentration of total antioxidants were improved by oil sources, but the sperm concentration was dependent on the levels of vitamin E. Therefore, salmon oil can be used in the diet of male pigs.

Delivering cholesterol or cholestanol to bull sperm membranes improves cryosurvival.

This study compared the effect of adding other cholesterol conjugates, which should incorporate into and increase sperm membrane fluidity at low temperatures thereby increasing cryosurvival. Ejaculates from each of four bulls were diluted to 120 million cells/ml in a Tris diluent and used in two experiments. Each experiment contained four treatments: No additive (control); 1.5mg CLC/120 million sperm (positive control); and 1.5mg cyclodextrin pre-loaded with cholestanol or desmosterol/120 million sperm. In the first experiment, fresh sperm were treated with cyclodextrins that were pre-loaded with cholesteryl conjugates and incubated for 15 min at 22 degrees C to allow incorporation of the conjugates. The percentages of motile sperm after exposure to solutions ranging from 0 to 1200 mOsm were used to evaluate the osmotic tolerance of the cells. The ability of treated sperm to bind to the bovine zona pellucida (ZP) and chicken egg perivitelline membrane (CEPM) was evaluated to determine if altering the sperm membrane affected the ability of sperm to bind to oocytes. In the final experiment, the cryosurvival rates of control and treated sperm were determined. Control and treated sperm were cryopreserved in a Tris diluent containing 10% egg yolk (EY) and 8% glycerol (final concentrations). Samples were thawed to determine the motility and ability of sperm to bind to the ZP and to CEPM using a CASA and epifluorescence microscope, respectively. Fresh sperm treated with CLC resulted in more binding to the ZP compared to all other treatments (P<0.05). No differences were observed between ZP and CEPM binding (P>0.05). The percentages of motile sperm were greater for fresh samples treated with cholesterol, cholestanol or desmosterol loaded cyclodextrin than control cells (P<0.05) when the sperm were exposed to anisosmotic conditions, and then returned to isosmolality. After cryopreservation the percentages of motile sperm and number of sperm binding to each CEPM were similar for sperm treated with CLC and cholestanol compared to sperm treated with desmosterol (P>0.05). All treatments provided greater motility and binding efficiency than control sperm (P<0.05). Therefore, adding cholesterol or cholestanol to bull sperm membranes improved cell cryosurvival.

Pregnancy rates and corpus luteum-related factors affecting pregnancy establishment in bovine recipients synchronized for fixed-time embryo transfer.

The objective was to investigate the influence of corpora lutea physical and functional characteristics on pregnancy rates in bovine recipients synchronized for fixed-time embryo transfer (FTET). Crossbred (Bos taurus taurus x Bos taurus indicus) nonlactating cows and heifers (n=259) were treated with the following protocol: 2mg estradiol benzoate (EB) plus an intravaginal progesterone device (CIDR 1.9g progesterone; Day 0); 400 IU equine chorionic gonadotropin (eCG; Day 5); prostaglandin F(2alpha) (PGF(2alpha)) and CIDR withdrawal (Day 8); and 1mg EB (Day 9). Ovarian ultrasonography and blood sample collections were performed on Day 17. Of the 259 cattle initially treated, 197 (76.1%) were suitable recipients; they received a single, fresh, quality grade 1 or 2 in vivo-derived (n=90) or in vitro-produced (n=87) embryo on Day 17. Pregnancy rates (23 d after embryo transfer) were higher for in vivo-derived embryos than for in vitro-produced embryos (58.8% vs. 31.0%, respectively; P<0.001). Mean (+/-SD) plasma progesterone (P(4)) concentration was higher in cattle that became pregnant than that in nonpregnant cattle (5.2+/-5.0 vs. 3.8+/-2.4 ng/mL; P=0.02). Mean pixel values (71.8+/-1.3 vs. 71.2+/-1.1) and pixel heterogeneity (14.8+/-0.3 vs. 14.5+/-0.5) were similar between pregnant and nonpregnant recipients (P>0.10). No significant relationship was detected between pregnancy outcome and plasma P(4), corpus luteum area, or corpus luteum echotexture. Embryo type, however, affected the odds of pregnancy. In conclusion, corpus luteum-related traits were poor predictors of pregnancy in recipients. The type of embryo, however, was a major factor affecting pregnancy outcome.

Effect of cholesterol or cholesteryl conjugates on the cryosurvival of bull sperm.

Different cholesterol conjugates-loaded-cyclodextrin was added to bull sperm to improve sperm quality after freezing. Ejaculates from four bulls were diluted to 120 million cells/ml in Tris (T) diluent and then sub-divided into 10 treatments as follow: no additive (control); 1.5mg CLC (positive control); 0.75 mg or 1.5mg of cyclodextrin pre-loaded with cholesterol conjugated to heptanoate, palmitate, pelargonate or stearate, and incubated for 15 min at 22 degrees C. The samples were then diluted 1:1 with 20% egg yolk (EY) in T diluent and cooled to 5 degrees C over a 2h. Upon reaching 5 degrees C, the samples were diluted 1:1 with T diluent containing 10% EY+16% glycerol, and allowed to equilibrate for 15 min, and packaged into 0.5 ml straws and frozen in static liquid nitrogen vapor for 20 min before being plunged into liquid nitrogen for storage. Straws were thawed and the sperm motility, viability and number sperm binding to perivitelline membrane were determined. The ability of bull sperm to bind to the oocyte membranes was conducted using the chicken egg perivitelline membrane (CEPM) as described by Barbato et al. [G.F. Barbato, P.G. Cramer, R.H. Hammerstedt, A practical in vitro sperm-egg binding assay that detects subfertile males. Biol. Reprod. 58 (1998) 686-699] and modified by Amorim et al. [E. Amorim, J.K. Graham, B. Spizziri, M. Meyers, L. Amorim, C. Torres, The effect of adding cholesteryl-heptanoate, -palmitate, -pelargonate, or -stearate loaded cyclodextrin on bull sperm cryosurvival, in: Proceeding 40th Annual Meeting of the Society for the Study of Reproduction (SSR), July, San Antonio, TX, EUA, 2007], where these authors did not observe difference between bovine zona pellucide and CEPM. Higher percentages of motile and viable sperm were maintained after thawing from bull sperm treated with CLC and pelargonate compared to all other treatments (P<0.05). Control samples and sperm treated with heptanoate, palmitate, or stearate loaded cyclodextrin exhibited similar motility percentages and viable sperm after freezing (P>0.05). The percentage of motile sperm and number sperm binding to chicken egg perivitelline membrane was higher for CLC and pelargonate compared to control (P<0.05). Therefore, adding either cholesterol or pelargonate to bull sperm membranes improved cell cryosurvival, whereas treatments with cyclodextrins pre-loaded with other cholesterol-like molecules did not.

The hypoosmotic swelling test in fresh rabbit spermatozoa.

The hypoosmotic swelling test (HOST) has proved to be a good tool for evaluating the membrane integrity of spermatozoa of various domestic animals including cattle, horses, and swine. However, the best approach for using this technique in rabbit semen has not been tested. The present study aimed to establish the best hypoosmotic solution (HS) for testing membrane integrity in fresh rabbit semen. Sucrose solutions with the following osmolarities were used: 50, 60, 75, 100, 125 and 150mOsm/L. Semen samples (n=30) were collected from five mature White New Zealand rabbits (six collections per rabbit) at 72h intervals. After macroscopic evaluation, 10microL of semen was immediately added to 2mL of each solution and incubated for 1h at 37 degrees C. Sequentially, 20microL of semen diluted in HS were evaluated with oil immersion using a phase-contrast microscope. A total of 200 spermatozoa were counted in at least five different fields, and sperm tails were classified as non-coiled, coiled, and strongly coiled. The respective percentages of spermatozoa with coiled tails (coiled plus strongly coiled) in the six solutions listed above were 54.8, 65.2, 54.3, 53.9, 38.9 and 29.4%. Percentage of strongly coiled spermatozoa was: 40.2, 51.0, 43.2, 41.5, 32.7 and 26.9 for the six solutions, respectively. According to total and strong coiling 60mOsm/L was superior to others treatments (P<0.05). Results suggest that the 60mOsm/L solution would be most desirable for use in HOST in fresh rabbit spermatozoa.

Sincronização de estro com CIDR reutilizado em cabras lactantes da raça Toggenburg tratadas com somatotropina bovina recombinante (r-bST) / Estrous synchronization with recycled CIDR in lactating Toggenburg does treated with recombinant bovine somatotropin (r-bST)

Avaliou-se a resposta de cabras tratadas com r-bST no protocolo de sincronização de estro. Foram utilizadas 26 cabras Toggenburg, divididas em dois tratamentos: T1 (n=13), tratadas com quatro injeções de 250mg de r-bST, a intervalos de 14 dias, e T2 (n=13), tratadas com solução salina (controle). Na semana seguinte à última injeção da r-bST, colocou-se o dispositivo intravaginal com progesterona (dia 0), previamente utilizado por cinco dias, e injetou-se PGF2alfa (22,5µg) nos animais dos dois tratamentos, e o dispositivo foi retirado no dia 6. Todas as fêmeas em estro foram submetidas à monta natural. A porcentagem de animais em estro e a taxa de gestação foram 76,9 e 70,0 e 84,6 e 72,7 por cento, no T1 e T2, respectivamente. Não houve diferença (P>0,05) na duração do estro, no intervalo tratamento-início do estro, no número de ovulações, nos intervalos: início e final do estro à ovulação e retirada do dispositivo à ovulação entre os animais dos dois tratamentos. O diâmetro médio dos folículos ovulatórios das fêmeas não diferiu (P>0,05). Durante a permanência do dispositivo, as concentrações séricas de progesterona apresentaram valores semelhantes (P>0,05) entre as cabras de T1 e T2. A r-bST não afetou a sincronização de estro.

The response of goats treated with r-bST in the estrous synchronization protocol was evaluated. Twenty-six Toggenburg females were divided in two treatments: T1 (n=13) treated with four injections of 250mg r-bST, at 14 days intervals, and T2 (n=13) treated with saline solution (control). The intravaginal device previously used by five days was inserted (day 0) one week after the last injection of r-bST and PGF2alpha (22.5µg) was injected in the animals of both treatments. The device was removed on day 6. All the females in estrus were bred by fertile bucks. The percentage of animals in estrus and the pregnancy rate were: 76.9 and 70, and 84.6 and 72.7 percent for goats in T1 and T2, respectively. The estrous cycle length; the interval from treatment to the onset of estrus; the ovulation number; and the intervals from the onset of estrus to ovulation, end of estrus to ovulation, and from device removal to ovulation were not affected by r-bST injection. The r-bST did not affect the diameter of the ovulatory follicles (P>0.05). Progesterone concentration showed similar values (P>0.05) among the goats of T1 and T2 during the treatment with device. The r-bST administration did not affect estrous synchronization.

Progesterone and behavioral features when estrous is induced in Alpine goats.

The objective of the present study was to evaluate the endocrine and behavioral features of estrous-induced Alpine goats. A total of 36 nulliparous, 40 non-lactating and 42 lactating does were treated with intravaginal 60 mg medroxyprogesterone acetate sponges for 9 d plus 200 IU eCG and 22.5 microg d-cloprostenol 24 h before sponge removal. Plasma progesterone concentration was analyzed from blood sampled on days 0 (sponge insertion), 5, 8 (cloprostenol administration) and 9 (sponge removal) in 11 nulliparous, 13 non-lactating and 11 lactating does. Estrous response did not differ (P>0.05) among nulliparous (97.2%), non-lactating (90.00%) and lactating does (85.7%). Interval to estrus and duration of estrus did not differ (P>0.05) among nulliparous (22.8+/-9.9 and 25.6+/-6.8h), non-lactating (23.7+/-15.8 and 25.0+/-6.0 h) and lactating does (22.2+/-10.4 and 24.9+/-4.2h). The accumulative percentage of does in estrus during the first 36 h after sponge removal was 88.1%. The correlation between interval to estrus and duration of estrus was r=-0.32 (P<0.001). Endogenous progesterone production is decreased until day 8 or suppressed by MAP on day 9. Conception rate was greater (P<0.01) in lactating (77.8%) than non-lactating (44.4%) but similar (P>0.05) to nulliparous (60.0%) goats. Estrus can be efficiently induced by means of hormonal treatment in goats and acceptable fertility can be obtained regardless of animal category.

Dinâmica folicular em cabras da raça Toggenburg em lactação tratadas ou não com somatotropina bovina recombinante / Follicular dynamics of lactating Toggenburg does treated with recombinant bovine somatotropin

Avaliou-se o efeito da injeção de somatotropina bovina recombinante (r-bST) sobre o ciclo estral de cabras. Foram utilizadas 24 fêmeas da raça Toggenburg, distribuídas em dois tratamentos: T1 (n=12), cabras tratadas com r-bST; e T2 (n=12), cabras tratadas com solução salina (controle). A partir da primeira injeção do tratamento, acompanhou-se o ciclo dos animais em estro até o estro subseqüente. O comprimento médio do ciclo estral e o período interovulatório não diferiram (P>0,05) entre os tratamentos. Foram verificados ciclos estrais de duas, três e quatro ondas de crescimento folicular. Não houve diferença (P>0,05) entre os tratamentos quanto ao número de ondas do ciclo estral. O número de folículos detectados com diâmetro >3mm nas cabras do T1 foi maior (P<0,05) que naquelas do T2 nos ciclos com duas (15,3±1,2 x 8,1±2,0), três (12,2±0,8 x 8,3±1,9) e quatro (12,7±1,7 x 8,8±2,5) ondas. O folículo dominante da segunda onda foi menor (P<0,05) que o da primeira e terceira ondas e também menor que o da onda ovulatória tanto para T1 quanto para T2. A concentração sérica de progesterona durante o ciclo estral não foi influenciada pelos tratamentos com r-bST (P>0,05). A r-bST não alterou a dinâmica folicular de cabras lactantes da raça Toggenburg, mas promoveu o aumento do número de folículos recrutados ³3mm durante o ciclo estral

The effect of the r-bST injection was evaluated on the goats estrous cycles. Twenty-four Toggenburg does were used in two treatments: T1 (n=12) treated with r-bST; and T2 (n=12) treated with saline solution (control). After the first r-bST injection, the estrous cycles were checked between two estrus. The estrous cycle length and interovulatory period of the goats did not differ between treatments (P>0.05). Estrous cycles with two, three and four waves of follicular growth were observed. The number of waves during the estrous cycle were not affected by the r-bST treatment (P>0.05). The number of 3mm follicles was different between T1 and T2 (P<0.05) for estrous cycles with two (15.3±1.2 x 8.1±2.0), three (12.2±0.8 x 8.3±1.9) or four (12.7±1.7 x 8.8±2.5) waves. The dominant follicle of the second wave was smaller (P<0.05) than the one of the first and third waves and smaller than the one of the ovulatory wave. The progesterone concentration during the estrous cycle of the animals did not differ (P>0.05) between treatments. The r-bST did not affect the ovarian response during the estrous cycle. The r-bST not affected the follicular dynamic of Toggenburg lactating does, but increased the number of emerging follicles >3mm during the estrous cycle

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

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

Perfil metabólico de touros da raça Nelore (Bos taurus indicus) confinados e tratados com somatotrofina bovina recombinante (r-bST) / Metabolic and hormonal profile of feedlot Nellore bulls (Bos taurus indicus) and treated with recombinant bovine somatotropin (r-bST)

Avaliaram-se os efeitos da administração da somatotrofina bovina recombinante (r-bST) sobre os metabólitos sangüíneos de touros da raça Nelore de duas diferentes idades. Foram utilizados 16 touros, distribuídos em um delineamento fatorial 2 x 2 (idades: jovens e adultos; r-bST: 0 e 500mg) com quatro animais por tratamento. A idade média dos animais foi de 13,37 e 20,62 meses para jovens e adultos, respectivamente. Quatro animais por tratamento receberam, a cada 14 dias, solução salina ou 500mg de r-bST, totalizando nove aplicações por animal, em um período experimental de 120 dias. Os touros foram alimentados com silagem de milho e ração concentrada à base de farelo de milho e soja, duas vezes por dia, fornecidas em baias individuais. As coletas de sangue foram realizadas a cada três dias, para determinação da concentração dos metabólicos sangüíneos. Para análise estatística, foram compilados dados a intervalo de três aplicações, o que constituiu um período (período 1, 2 e 3). As concentrações de ácidos graxos não-esterificados (NEFA) foram analisadas semanalmente. As concentrações séricas de colesterol, proteína total e plasmáticas de glicose diferiram para os períodos e nos grupos de tratamentos (P<0,05). As concentrações de NEFA foram influenciadas pelas semanas de coleta (P<0,05), mas não pelo tratamento com ou sem r-bST (P>0,05).

This study was carried out to evaluate the effect of recombinant bovine somatotropin (r-bST) administration on profiles of blood metabolites of two different ages Nellore bulls. Sixteen bulls were randomly allotted in a factorial arrangement 2 x 2 (ages: youngs and adults; and r-bST dose: 0 and 500 mg) with four animals per treatment. The mean ages of the young and adult animals were 13.37 and 20.62 months, respectively. Four animals per treatment received saline solution or r-bST 500mg, every 14 days, totaling nine applications per animal during 120 days. The Bulls were fed corn silage and concentrated diet based on corn crumb and soybean meal, twice a day, in individual stalls. Blood was collected every three days for metabolic evaluation. The statistical analyses of the data were performed in three applications, considering three periods (1, 2 and 3). Non-esterified fatty acid (NEFA) concentrations were weekly analyzed. Serum cholesterol, total protein and glucose levels were affected either by period or the treatment (P<0.05). The NEFA was affected by weeks of collection (P<0.05) but not by r-bST treatment (P>0.05).

Indução de estro em cabras da raça Toggenburg com dois diferentes dispositivos intravaginais / Estrous induction in Toggenburg goats using intravaginal devices

Doze cabras nulíparas da raça Toggenburg foram distribuídas em dois tratamentos (T1 e T2) para indução do estro. O T1 (n=6) consistiu na inserção da esponja impregnada com 60mg de acetato de medroxiprogesterona, associado à aplicação de 50æg do análogo sintético d-cloprostenol (PGF). No quarto dia, foram aplicadas 250UI de gonadotropina coriônica eqüina (eCG) e, no quinto, a esponja foi retirada. O T2 (n=6) diferiu somente quanto ao dispositivo empregado, que foi o CIDR-G®. Seis cabras do T1 e seis do T2 entraram em estro depois da retirada dos dispositivos, sendo que 83,3 (5/6) e 33,3 por cento (2/6) ficaram gestantes em T1 e T2, respectivamente. O intervalo da retirada do dispositivo ao início do estro não diferiu entre tratamentos (P>0,05). As características ovulatórias não foram influenciadas pelos tratamentos. O intervalo da retirada do dispositivo à ovulação, para ambos os protocolos de indução do estro, não diferiu (P>0,05) entre tratamentos. Ambos os dispositivos foram eficientes em induzir o estro.

Twelve Toggenburg breed nuliparous female goats were randomly assigned to two treatments intended to induce estrus. On day zero, animals on T1 (n=6) were treated with an intravaginal sponge impregnated with 60mg of medroxyprogesterone acetate plus 50æg of PGF analogue. The T1 goats received eCG (250IU) on day 4, and on day 5 the sponge was removed. The T2 goats (n=6) received CIDR-G® as intravaginal sponge plus 50mg of PGF analogue. All goats expressed behavioral estrus, and the pregnancy rates were 83.3 (5/6) and 33.3 percent (2/6) for T1 and T2, respectively. The interval from withdrawal of the device to onset of estrus did not differ between treatments (P>0.05). Ovulatory traits also were not affected by treatments. The interval between CIDR-G® removal and ovulation for T1 and T2 goats were similar (P>0.05). Both sponge and CIDR-G were equally efficient in inducing the estrus behavior in goats.

Taxa de gestação em cabras Alpinas e Saanen tratadas com hCG no terceiro dia após o estro / Pregnancy rate and progesterone concentration of Alpine and Saanen goats treated with hCG the third day after estrus

Avaliou-se o efeito da aplicação da gonadotrofina coriônica humana (hCG) sobre a taxa e duração da gestação e sobre a concentração plasmática de progesterona (P4) em cabras lactantes das raças Alpina (83) e Saanen (60), na estação de acasalamento induzida pelo programa de fotoperíodo artificial. Os animais foram distribuídos em dois tratamentos após a cobrição; as cabras do tratamento 1 (T1 controle) receberam solução salina via intramuscular (1ml), e as do tratamento 2 (T2) receberam 250UI do hCG, no terceiro dia no pós-estro. As taxas de gestação, detectadas por exame ultra-sonográfico, realizado no 35° após a cobrição, para as cabras das raças Alpina e Saanen controle e tratadas, foram de 80,4; 70,3; 72,7; 81,5 por cento, respectivamente, não diferindo entre os tratamentos e entre as raças (P>0,05). A taxa média de gestação foi 77,2 e 75,0 por cento para os animais controle e tratados, respectivamente. A duração da gestação não foi influenciada pelos tratamentos (P>0,05). As amostras de sangue para análise da concentração plasmática de progesterona (P4) foram coletadas de cinco cabras Alpina por tratamento, no dia do estro (dia 0) e aos 3, 8, 15, 21, 42 e 60 dias após o estro. Não houve diferença na concentração plasmática média de P4 entre os tratamentos (P>0,05), sendo de 5,84ng/ml para T1 e 5,76ng/ml para T2. Observou-se diferença em relação aos dias de coleta (P<0,05). O hCG aplicado no terceiro dia pós-estro não alterou a taxa de gestação e nem a concentração de P4.

Efeito da condição corporal ao parto sobre a produção e composição do leite, a curva de lactação e a mobilização de reservas corporais em vacas da raça Holandesa / Effects of body condition at calving on milk yield and composition, lactation curve and body reserve mobilization of Holstein cows

Avaliaram-se os efeitos do escore da condição corporal ao parto sobre a produção e composição do leite, a curva de lactação e o padrão de mobilização de reservas corporais em vacas da raça Holandesa. Foram utilizadas 51 vacas, sendo 13 primíparas e 38 multíparas, distribuídas em delineamento inteiramente ao acaso, segundo a ordem de partos - primíparas e multíparas - e a classe de escore da condição corporal ao parto (ECCP) - classe 1 ECCP igual ou superior a 3,25, e classe 2 ECCP igual ou inferior a 3,0. Para avaliar o padrão de mobilização de reservas corporais, foram formados grupos de vacas em função do ECCP e do nível de produção de leite. Nas primíparas, não foram observados efeitos da ECCP sobre a produção e a composição do leite e sobre a curva da lactação, exceto para porcentagem de gordura. Nas multíparas, as vacas da classe 1 produziram mais leite e mais componentes do leite, e a curva da lactação mostrou pico de produção mais alto. As vacas de maior ECCP e maior produção de leite apresentaram padrão de mobilização de reservas corporais mais acentuado no início da lactação e maior peso corporal no pré-parto e ao parto. O peso corporal e a mudança de peso corporal ao parto e no início da lactação não foram influenciados pelo escore de condição corporal ao parto e pela produção de leite.