49 research outputs found
Endometrial expression of genes involved in growth factor, cytokine, hormone, and WNT signaling during the early estrous cycle of the cow.
No full textNotulae su alcune tribù in Sardegna
No full textA. Ibba ha curato i §§ 2-3 (pp. 83-85), il primo dedicato a Cornus, centro per il quale rimane sconosciuta la tribù alla quale in prevalenza erano iscritti i suoi abitanti (il tribulo della Quirina qui attestato era più verosimilmente originario di Karales); il secondo a L. Valerius Potitus, tribulo della Oufentina entrato tuttavia a far parte della nobilitas sulcitana forse in virtù del particolare statuto di Sulci, municipio latin
THE EFFECT OF OVULATION-INDUCING FACTOR (OIF) IN BOVINE SEMINAL PLASMA ON OVARIAN FUNCTION IN CATTLE
No full textThree experiments were designed to gain an understanding of the role of ovulation-inducing factor (OIF) present in bovine seminal plasma. Within species, seminal plasma was pooled from 1 to 4 ejaculates per male (n=160 bulls, n=4 llamas in Experiments 1 and 2, and n=95 bulls in Experiment 3). The volume of seminal plasma used for treatment was adjusted to a total dose of 250 µg of OIF. Experiment 1 was done to verify the bioactivity of OIF in bovine seminal plasma. Mature female llamas were assigned randomly to be treated intramuscularly (i.m.) with either 10 ml of phosphate buffered saline (PBS, negative control, n=5), 50 µg GnRH (positive control, n=5), 6 ml of llama seminal plasma (n=6) or 12 ml of bull seminal plasma (n=6). Experiment 2 was done to determine the effect of OIF in bovine seminal plasma on LH-induced ovulation and luteal development. Beef heifers with a CL and a growing follicle ≥10 mm were given a luteolytic dose of prostaglandin followed by 25 mg pLH 12 h later. Heifers were assigned randomly to three groups and given 10 ml bovine seminal plasma i.m. 12 h after pLH treatment (n=10), bovine seminal plasma i.m. within 4 h after ovulation (n=9), or no further treatment (control, n=10).Experiment 3 was done to determine the effect of OIF in bovine seminal plasma on LH release, ovulation and luteal development. Ovulation in beef heifers was synchronized using a protocol with progesterone and estradiol. Six days after ovulation, , when a mature CL and a dominant follicle of 11-13 mm diameter were expected to be present, heifers were assigned randomly to four groups (n=8 per group) using a 2-by-2 design and treated with either pLH or phosphate-buffered saline i.m., followed 12 h later by treatment with either 10 ml bovine seminal plasma or phosphate-buffered saline i.m.; i.e., LH+PBS, LH+SP, PBS+SP, and PBS+PBS groups. In all experiments, ovulation and CL development were monitored by transrectal ultrasonography. In Experiment 1, llamas were scanned daily from treatment to Day 6 after treatment, while in the other two experiments ovulations were monitored every 4 h and CL development was monitored daily until the next ovulation. Ovulation rates were compared among groups by Fisher’s exact test, and continuous data were compared among groups by ANOVA for repeated measures. Single point data were compared by ANOVA. In Experiment 1, ovulation was detected in 0/5, 4/5, 4/6, 4/6 in PBS, GnRH, llama seminal plasma, and bovine seminal plasma groups, respectively (P<0.05). No difference was detected among groups in luteal development. In Experiment 2, all ovulations in the pre-ovulation treatment group occurred within a 4 h period, while the range for other groups was 22 h (P<0.0001). No difference was detected among groups in luteal development; however, plasma progesterone concentrations tended to be greater in the heifers treated with seminal plasma post-ovulation compared to the other two groups (treatment-by-day interaction, P=0.1). In Experiment 3, ovulations were detected in 5/8, 4/8, 0/7, 0/8 in pLH, pLH+SP, SP and control groups, respectively (P<0.05). Corpora lutea present at the time of treatment took longer to decrease significantly in size from the time they reached maximum size in heifers treated with seminal plasma (p=0.04), but, plasma progesterone concentrations did not differ among groups during this same period. Nevertheless, there was a more rapid increase in plasma progesterone concentration by 24 h after seminal plasma treatment than those not treated with seminal plasma (P=0.03). Results confirm the presence of bioactive OIF in bull seminal plasma and showed that bovine and llama seminal plasma have similar ovulatory and luteotrophic effects using a llama bioassay. Moreover, treatment of sexually mature heifers with OIF from bovine seminal plasma influenced the timing of ovulation and the duration of luteal function.
Dose-dependent effects of rumen-protected choline on hepatic metabolism during induction of fatty liver in dry pregnant dairy cows
No full textObjectives were to determine the effects of supplementing increasing amounts of choline ion on hepatic composition and mRNA abundance in pregnant dry cows subjected to a fatty liver induction protocol. Holstein cows (35 primiparous and 41 multiparous) at mean (± standard deviation) of 211 ± 9.9 days of gestation were blocked by body condition (3.59 ± 0.33) andassigned to receive 0, 6.45, 12.90, 19.35, and 25.80 g/day of choline ion as rumen-protected choline (RPC) as a top-dress for 14 days. Cows were fed for ad libitum intake on days 1 to 5andrestricted to 30% of the required net energy for lactation from days 6 to 14 of the experiment. Hepatic tissue was sampled on days 5 and 14 and analyzed for concentrations of triacylglycerol and glycogen, and mRNA abundance was investigated. Orthogonal contrasts evaluated the effects of supplementing RPC (0 g/day vs. rest), and the linear, quadratic, and cubic effects of increasing intake of choline ion from 6.45 to 25.80 g/day. Results are depicted in sequence of treatments from 0 to 25.8. During feed restriction, RPC reduced the concentration of hepatic triacylglycerol by 28.5% and increased that of glycogen by 26.1%, and the effect of increasing RPC intake on triacylglycerol was linear (6.67 vs. 5.45 vs. 4.68 vs. 5.13 vs. 3.81 ± 0.92% wet-basis). Feeding RPC during feed restriction increased abundance of transcripts involved in choline metabolism (CHKA, PLD1), synthesis of apolipoprotein-B100 (APOB100), and antioxidant activity (GPX3), and decreased the abundance of transcripts involved in hepatic lipogenesis (DGAT2, SREBF1) and acute phase response (SAA3). Most effects were linear with amount of choline fed. Changes in hepatic mRNA abundance followed a pattern of reduced lipogenesis and enhanced lipids export, which help explain the reduced hepatic triacylglycerol content in cows fed RPC. Choline exerts lipotropic effects in dairy cows by altering transcript pathways linked to hepatic lipids metabolism.Fil: Arshad, Usman. University of Florida; Estados UnidosFil: Zenobi, Marcos G.. Universidad Nacional de Córdoba; ArgentinaFil: Tribulo, Paula. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Staples, Charles R.. University of Florida; Estados UnidosFil: Santos, José E. P.. University of Florida; Estados Unido
Consequences of in vitro production of embryos with or without colony-stimulating factor 2 in culture medium on morphometric features of the bovine conceptus at day 86 of gestation.
No full textInfluencia de la suplementación del medio de cultivo con ácido linoleico en la supervivencia a la congelación de embriones bovinos
No full textStudies report that the addition of linoleic acid to bovine embryo production media in vitro improves its resistance to conventional freezing. In this study the effect on survival of in vitro bovine embryos under freezing was evaluated by the addition of linoleic acid (LA) in the culture medium on days 3 or 5. A total of 1452 oocytes were recovered and assigned to 4 experimental groups and a control group. Six replicates were made to obtain approximately 100 freeze-thawed embryos per group. Group 1: 100 M on Day 3, group 2: 50 M on Day 3, group 3: 100 M on Day 5, group 4: 50 M on Day 5. The embryos were frozen and one week after they were thawed to evaluate the percentages of re-expansion (24 h) and hatching (72 h). The results were analyzed by ANOVA and when the differences were significant, the means between the groups were compared by Fischer's LSD Test (p <0.05). It was observed that the percentage of re-expansion was significantly improved with the addition of 50 μM LA on Day 5 (54.94 ± 28.8 vs. 19.19 ± 28.4, p = 0.001) and the percentage of hatching with the addition of 50 μM of LA at day 3 (37.9 ± 18.3 vs. 9.02 ± 12.0, p = 0.014), when them were compared with the control group. In conclusion, the addition of linoleic acid improves the survival to freezing of bovine embryos produced by in vitro techniquesEstudios reportan que la adición de ácido linoleico en los medios de producción de embriones bovinos in vitro, mejora su resistencia a la congelación convencional. En este estudio se evaluó el efecto en la supervivencia de embriones bovinos in vitro a la congelación, mediante la adición de ácido linoleico (LA) en el medio de cultivo los días 3 o 5. Un total de 1452 oocitos fueron recuperados y asignados a 4 grupos experimentales y un grupo control. Se realizaron seis réplicas, para obtener aproximadamente 100 embriones congelables por grupo. Grupo 1: 100 M en Día 3, grupo 2: 50 M en Día 3, grupo 3: 100 M en Día 5, grupo 4: 50 M en Día 5. Los embriones se congelaron y a la semana fueron descongelados para evaluar los porcentajes de re-expansión (24 h) y de eclosión (72 h). Los resultados fueron analizados mediante ANOVA y cuando las diferencias fueron significativas, se compararon las medias entre los grupos por el Test LSD de Fischer (p < 0.05). Se observó que el porcentaje de re-expansión mejoró significativamente con la adición de 50 M de LA en el Día 5 (54.94 ± 28.8 vs. 19.19 ± 28.4, p = 0.001) y el porcentaje de eclosión con la adición de 50 M de LA en el Día 3 (37.9 ± 18.3 vs. 9.02 ± 12.0, p = 0.014), cuando se comparó con el grupo control. En conclusión, la adición de ácido linoleico mejora la supervivencia a la congelación de los embriones bovinos producidos mediante técnicas in vitrFil: Bernal Ballesteros, Beatriz H.. Instituto de Reproducción Animal Córdoba; Argentina. Vitrogen Colombia S.A.S; ColombiaFil: Tribulo, Humberto Elias. Instituto de Reproducción Animal Córdoba; ArgentinaFil: Mutto, Adrián Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Bo, Gabriel Amilcar. Instituto de Reproducción Animal Córdoba; Argentina. Universidad Nacional de Villa María; Argentin
Improved bovine in vitro embryo production with sexed and unsexed sperm selected by chemotaxis
No full textAssisted reproductive techniques (ART) have been widely used in farm animals in the last decades. Sexed cryopreserved spermatozoa, ovum pick up, in vitro embryo production and transfer constitute the ART that have revolutionized the dairy industry. However, the efficiency of some of these techniques is still low due in part to sperm quality, which influences fertilization, embryo development and implantation. The Sperm Selection Assay (SSA), based on sperm chemotaxis towards progesterone, provides a sperm subpopulation enriched with spermatozoa that are capacitated, with intact DNA and low level of oxidative stress. Since the SSA selects a sperm subpopulation at optimum physiological state, the application of the SSA may improve the efficiency of the current ART. The aim of this study was to adapt the SSA for unsexed and sexed bovine frozen-thawed semen samples, and then to test whether sperm selection by the SSA improves the cleavage rate of bovine embryos in vitro. The optimal SSA conditions to obtain the higher sperm accumulation percentage given by chemotaxis were the same for both unsexed and sexed semen samples. Thus, sperm accumulation in W2 was significantly higher when: 2 million sperm per mL were placed in W1 (unsexed samples: 12 ± 1%, p = 0.002; sexed samples: 14 ± 3%, p = 0.02); 1 pM progesterone was placed in W2 (unsexed sample: 9 ± 1%, p = 0.009; sexed samples: 11 ± 2%, p = 0.02); and to incubate the SSA device for 10 min (unsexed samples: 17 ± 2%, p = 0.007; sexed samples: 10 ± 1%, p = 0.004). We found that the quality of spermatozoa recovered from W2 in unsexed and sexed semen was enhanced. Thus, the capacitation index was significantly increased (unsexed samples: 1.75 ± 0.1, p = 0.0001; sexed samples: 1.76 ± 0.2, p = 0.004), while DNA fragmentation index was significantly decreased (unsexed samples: 0.33 ± 0.07, p = 0.0003; sexed samples: 0.32 ± 0.04, p = 0.002). Moreover, the cleavage index of oocytes fertilized with either unsexed or sexed SSA-selected sperm was significantly improved (unsexed samples: 3.2 ± 0.4, p = 0.0001; sexed samples: 2.3 ± 0.33, p = 0.03). Thus, we show that the SSA can be used to recruit a bovine sperm subpopulation at optimal functional state regardless of whether the sample is previously sexed, and that this optimal state improves bovine embryo cleavage rate.Fil: Dominguez, Esteban Mauricio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Biología Celular y Molecular; ArgentinaFil: Moreno, Ayelen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Biología Celular y Molecular; ArgentinaFil: Guidobaldi, Héctor Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Biología Celular y Molecular; ArgentinaFil: Tribulo, Humberto Elias. Instituto de Reproduccion Animal Córdoba; ArgentinaFil: Giojalas, Laura Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Biología Celular y Molecular; Argentin
128 BOVINE SEMINAL PLASMA INDUCES OVULATION IN LLAMAS
No full text
Ovulation-inducing factor (OIF) is a protein present in the seminal plasma of several species, including llamas, alpacas, pigs, cattle, sheep, horses and rabbits. In an initial study (Ratto et al. 2006 Theriogenology 66, 1102–1106), bovine seminal plasma induced ovulations in 26% (5/19) of llamas compared with 0% (0/19) in the placebo group, but induced proportionately less than in llamas treated with alpaca or llama seminal plasma (100%). It is important to highlight that treatments were based on volume of seminal plasma; the actual dose of OIF was unknown. In a later study (Tanco et al. 2011 Biol. Reprod. doi:10.1095/biolreprod.111.091876), OIF from llama seminal plasma had a dose-dependent effect on ovulation rate, corpus luteum (CL) diameter and progesterone production in llamas. The present study was designed to test the hypothesis that bovine seminal plasma induces ovulation and CL development in llamas comparable with that of llama seminal plasma, based on total dose of OIF. Within species, seminal plasma was pooled from 1 to 4 ejaculates per male (n = 145 bulls, n = 4 llamas). The concentration of OIF in the pooled seminal plasma was measured by radioimmunoassay and the volume of seminal plasma used for treatment was adjusted to reach a total dose of 250 μg of OIF. Mature female llamas were assigned randomly to 4 groups and given a single intramuscular dose of 10 mL of PBS (negative control, n = 5), 50 μg of gonadotropin-releasing hormone (GnRH; positive control, n = 5), 6 mL of llama seminal plasma (n = 6), or 12 mL of bull seminal plasma (n = 6). Ovulation and CL development were monitored by transrectal ultrasonography. The incidence of ovulation was compared among groups by Fisher's exact test. Nonserial data (i.e. follicle size at treatment, maximum CL diameter, day of maximum CL diameter and first day of CL detection) were compared among groups by ANOVA. The diameter of the preovulatory follicle at treatment did not differ among groups (P = 0.10). The incidence of ovulation was 0/5, 4/5, 3/6 and 4/6 in the groups treated with PBS, GnRH, llama seminal plasma and bovine seminal plasma, respectively (P < 0.05). The incidence of ovulation did not differ among llamas treated with GnRH, llama seminal plasma, or bovine seminal plasma. Among the treatments that elicited ovulation, neither the maximum CL diameter nor the day of maximum CL diameter differed (P = 0.30 and P = 0.24, respectively). In addition, no difference was detected in the day of first detection of the CL (P = 0.25). Results document the bioactivity of OIF in the bovine seminal plasma of Bos taurus. These findings further support the notion that OIF is highly conserved among mammals and that seminal plasma exerts its effect in an OIF dose-related manner.
This research was supported by the Natural Sciences and Engineering Research Council of Canada.
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Heat maps including differently (<i>P</i> ≤ 0.10) expressed transcripts affected by the linear effect of amount of choline ion supplemented as rumen-protected choline (RPC).
No full textCows were supplemented with RPC to supply 0, 6.45, 12.90, 19.35 or 25.80 g/day of choline ion and the linear orthogonal contrast evaluated the effect of increasing the amount from 6.45 to 25.80 g/day. Panel A represents hepatic tissue sampled on day 5, whereas panel B represents the hepatic tissue sampled on day 14 of the experiment. Transcripts were separated using the average linkage clustering method and following the Euclidean distance measurement approach. The mRNA abundance increases from red to green, and data presented on a Z-score based scaling system.</p
Heat maps including differently (<i>P</i> ≤ 0.10) expressed transcripts affected by supplementing choline (0 vs. mean of rest) as rumen-protected choline (RPC).
No full textCows were supplemented with RPC to supply 0, 6.45, 12.90, 19.35 or 25.80 g/day of choline ion. Panel A represents hepatic tissue sampled on day 5, whereas panel B represents the hepatic tissue sampled on day 14 of the experiment. Transcripts were separated using the average linkage clustering method and following the Euclidean distance measurement approach. The mRNA abundance increases from red to green, and data presented on a Z-score based scaling system.</p
