303 research outputs found
Embryo production
No full textResearchers and technicians have developed several protocols for the production of embryos both in vitro and in vivo to be used both in animal breeding to increase the number of superior genotypes, and as a research tool. In vivo embryo production by Multiple Ovulation and Embryo Transfer (MOET) still accounts for the majority of embryos produced worldwide, but it has high costs and the number of produced embryos is often highly variable and unpredictable because of the donor effect. The application of MOET technologies requires the selection of valuable donors in perfect gynecological conditions and the administration of a superovulatory treatment to increase the number of growing follicles. Embryos are generally recovered 6-7 days after the induction of ovulation and either transferred to synchronized recipients or frozen. In vitro embryo production (IVP) is a newer and more flexible approach, although it requires specific laboratory expertise and equipment. Oocytes can be obtained both from ovaries collected at the slaughterhouse or from live donors by follicle aspiration. Cumulus-oocyte complexes are then selected and processed in vitro for embryo production. This technology involves three major steps, oocyte maturation, fertilization and embryo culture up to the blastocyst stage, which require different culture media and incubation conditions. The goal of increasing efficiency of in vitro embryo production has been the driving force for much of the applied research in embryo biology and culture. Yet, in vivo produced embryos are still of higher quality, as evidenced by higher implantation rates after transfer and cryosurvival
Observational study on a novel management system involving 10 lambings per year in one high-yield dairy ewe farm
No full textObjectives: In order to reduce non-productive days in dairy
ewe production, the “accelerated sheep mating systems” can
be used. One example is the STAR system, which involves up
to 5 lambings/ewe in 3 years (1.2 to 1.4 lambing/ewe/year)
through 5 successive annual breeding and lambing seasons
(5LY). Despite its feasibility, a major disadvantage to this system
is an irregular distribution of the workload throughout the
year. For instance, the farm staff capacity is easily overwhelmed
during the lambings periods, resulting in a deficient
care of the newborns. In an attempt to distribute the workload
more evenly, a high-yielding Lacaune farm transitioned from
the 5LY system to a novel one consisting on 10 lambing periods
per year (10LY). The present study examines the efficiency,
productivity and workload concentration in this farm under
both systems. Its goal was to determine the effects of a more
intensive management system on the farm’s productivity, animal
welfare and workload distribution.
Material and methods: This observational study was performed
in a high-yielding Lacaune dairy ewe farm (“Granja Cerromonte”,
Spain). The 5LY system was performed from 2010 to
2012, and the 10LY system from 2014 to 2015. Years 2009 and
2013 were considered transition years. During this period,
27,415 lactations were recorded from an average of 3,746
ewes/year.
Results: Daily production (1.70 ± 0.62 l/d vs 1.73 ± 1.66; P =
0.038), interlambing period (302 ± 44 vs 283 ± 50 d; P <
0.0001) and lambings/ewe/year (1.30 ± 0.01 vs1.42 ± 0.01; P <
0.05) slightly worsened in the 10LY system compared to the
5LY one. In contrast, milk yield/lactation (370 ± 156 vs. 349 ±
185 L), lactation length (218±75 vs 192 ± 75 d) and dry period
length (53.5 ± 38.3 vs 69.1 ± 34.8 d) (all P < 0.0001) were better
in the 10LY system. Most importantly, the workload distribution
improved by the 10LY system implementation. During
2010–2012, an average of 889.19 ± 158.47 lambings/lambing
period (range, 664 to 1 291) was recorded, resulting in an average
of 1,502.73 ± 267.82 live newborn lambs/lambing period
and 20.80±18.73 lambings/day (range, 1 to 110). There were
500.6 lambs and 296.6 lambings per worker during lambings
periods. Extra work hours were necessary at peak lambings/
day. However, during 2014–2015, an average of 443.66 ±
253.18 lambings/lambing period (range, 85 to 937) was recorded,
resulting in 709.85 ± 405.10 live newborn lambs/lambing
period and 15.16±7.83 lambings/day (range, 1 to 51). There
were 354.5 lambs and 221.5 lambings per worker during lambing
periods. Since the lambing and lamb related workload was
better distributed in the 10LY-period, the workload/worker fell
by 50%, needing only two workers/lambing season to take care
of the lambings and lamb pens in the 10LY system (354.5
lambs and 221.5 lambing per worker), compared to the three
necessary in the 5LY one (500.6 lambs and 296.6 lambing per
worker). Further, culling rate decreased (35.39 ± 0.53 vs 42.51
± 7.51 % P=0.294) and higher-order lactations increased
(24.17 vs 16,08%, P<0.0001) which could be the result of better
ewe and lamb management. Another possible benefit could
be the increase in the worker’s welfare, since the workload
does not concentrate so drastically in certain days.
Conclusions: Our study suggests that a 10LY herd management
system can be compatible with good profitability and productivity
and, more importantly, better animal welfare due to
lack of animal overcrowding and better care of lambs and ewes
during lambing. Furthermore, it could also mean better working
conditions for the farm staff, since the workload is more uniformly
distributed throughout the year.Sappor
Effect of aging on follicular function may be relieved by exogenous gonadotropin treatment in a sheep model
No full text"The current study investigated hormonal and ovarian changes during physiological reproductive aging in Sarda ewes. In a first experiment, follicular and corpus luteum dynamics were compared during an induced oestrus cycle in aged (12-14 years) and young adult ewes (4-5 years). Oestrus cycle characteristics did not differ between the two experimental groups. However, follicular function during the follicular phase showed significant alterations in aged ewes, as determined by a lack of dominance effect and by lower mean values of circulating oestradiol (E(2)) and inhibin levels, compared with young adult ewes. In a second experiment, differences in follicle growth, hormonal milieu and oocyte quality in response to exogenous FSH administration were assessed in aged and adult ewes. No differences were recorded in ovarian response to FSH treatment between young adult and aged ewes, as evaluated by ultrasonographic data and circulating concentrations of LH, E(2) and inhibin-A. Although the total number of recovered oocytes was similar in the two age groups, the number of good quality oocytes selected for IVM was significantly lower in aged ewes compared with adult ones. Thereafter, no differences were recorded in cleavage rates, total blastocyst output, embryo developmental kinetic and quality between aged and adult groups. In conclusion, this study demonstrated that reproductive aging in sheep is associated with impaired follicle functionality and an increase in the proportion of oocytes showing morphological abnormalities. However interestingly, oocyte developmental competence in vitro and embryo cryotolerance were not affected by the aging process, when only good quality oocytes were chosen.
Towards common standards on rights of suspected and accused persons in criminal proceedings in the EU? CEPS Liberty and Security in Europe, February 2010
No full textThis paper examines the Roadmap for strengthening procedural rights of suspected or accused persons in criminal proceeding in the EU that was adopted by the Council on 30 November 2009. It begins with a brief exposition of the general policy framework for understanding the Council’s Roadmap and its connection with the Stockholm Programme, subsequently adopted by the European Council of 10/11 December 2009, which spells out the policy priorities that will guide the EU’s AFSJ for the years 2010-14. Secondly, it provides an analysis of the proposed measures contained in the Roadmap and reviews their compatibility with what should have been included according to existing European standards; here special mention is made to the European Convention of Human Rights (ECHR) and the jurisprudence of the European Court on Human Rights (ECtHR). Third, the paper offers some critical reflections addressing the provisions encapsulated by the proposed Roadmap. Finally, the author puts forward a set of policy recommendations aiming at improving a future common legislative framework on procedural rights in the EU
Use of propylene-glycol as a cosolvent for GnRH in synchronization of estrus and ovulation in sheep
No full textThe foreseen shortage of eCG for estrus synchronization in sheep makes necessary the development of alternative protocols. The aim of the present work was to evaluate the reproductive response of sheep in breeding season to the administration of GnRH using propylene-glycol as a cosolvent and the subcutaneous route for slowing and extending the release of GnRH, as well as the most adequate timing for such administration. In the present study, protocols based on a short-term CIDR treatment and a single subcutaneous dose of GnRH in propylene-glycol at 36 h after CIDR removal induced a similar ovarian response to protocols based on administration of eCG at CIDR removal or intramuscular GnRH in distilled water at 56 h after. In such protocol, 80% of the animals developed estrus in a narrow timing (75% between 36 and 48 h after CIDR removal), and all of them also ovulated in a narrow window (87.5% between 72 and 76 h after CIDR removal, with 62.5% between 72 and 76 h) and showed a similar ovulation rate and plasma progesterone concentrations at the induced estrous cycle. Hence, administration of GnRH in propylene-glycol may constitute an alternative to traditional protocols based on the administration of eCG
Anti-Mullerian hormone as an age-related predictor of the antral follicle count and the response to exogenous FSH ovarian reserve test in sheep
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