Short communication: An association analysis between one missense polymorphism at the SREBF1 gene and milk yield and composition traits in goats

Sterol regulatory element binding transcription factor 1 (SREBF1) regulates the expression of genes involved in the biosynthesis of fatty acids and cholesterol. Herewith, we have sequenced the near-complete coding region and part of the 3?UTR of the goat SREBF1 gene. In doing so, we have detected a missense c.353CT polymorphism causing a proline to leucine substitution at position 118 (P118L). An association analysis with milk composition traits recorded in MurcianoGranadina goats only revealed a statistical tendency linking SREBF1 genotype and milk omega-3 fatty acid content. The lack of significant associations suggests that the P118L substitution does not involve a functional change.Le facteur de transcription de´nomme´ Sterol regulatory element binding transcription factor 1 (SREBF1) re´gule l’expression des ge`nes implique´s dans la biosynthe`se des acides gras et du choleste´rol. Dans cette e´tude, nous avons se´quence´ la quasi-totalite´ de la re´gion codante et une partie du la re´gion 3?UTR du ge`ne SREBF1 de la che`vre. Ce travail, nous a permis d’identifier un polymorphisme non-synonyme c.353CT causant la substitution d’une Proline en Leucine a` la position 118. L’e´tude d’association avec la composition du lait enregistre´e en che`vres Murciano-Granadina, a re´ve´le´ seulement une tendance statistique reliant SREBF1 ge´notype et l’acide gras ome´ga-3 du lait. L’absence d’associations significatives sugge`re que la substitution P118L n’implique pas un changement fonctionnel

Diminution of Voltage Threshold Plays a Key Role in Determining Recruitment of Oculomotor Nucleus Motoneurons during Postnatal Development

The size principle dictates the orderly recruitment of motoneurons (Mns). This principle assumes that Mns of different sizes have a similar voltage threshold, cell size being the crucial property in determining neuronal recruitment. Thus, smaller neurons have higher membrane resistance and require a lower depolarizing current to reach spike threshold. However, the cell size contribution to recruitment in Mns during postnatal development remains unknown. To investigate this subject, rat oculomotor nucleus Mns were intracellularly labeled and their electrophysiological properties recorded in a brain slice preparation. Mns were divided into 2 age groups: neonatal (1–7 postnatal days, n = 14) and adult (20–30 postnatal days, n = 10). The increase in size of Mns led to a decrease in input resistance with a strong linear relationship in both age groups. A well-fitted inverse correlation was also found between input resistance and rheobase in both age groups. However, input resistance versus rheobase did not correlate when data from neonatal and adult Mns were combined in a single group. This lack of correlation is due to the fact that decrease in input resistance of developing Mns did not lead to an increase in rheobase. Indeed, a diminution in rheobase was found, and it was accompanied by an unexpected decrease in voltage threshold. Additionally, the decrease in rheobase co-varied with decrease in voltage threshold in developing Mns. These data support that the size principle governs the recruitment order in neonatal Mns and is maintained in adult Mns of the oculomotor nucleus; but during postnatal development the crucial property in determining recruitment order in these Mns was not the modifications of cell size-input resistance but of voltage threshold

Informe: Derecho del trabajo y de la seguridad social en España en 2013. Algunos puntos críticos

Este documento intenta reflejar algunos de los principales cambios y novedades del ordenamiento laboral español en 2013, levantando acta de cómo la mutabilidad de nuestro Derecho del Trabajo es imparable. Este informe, consciente de ello, ofrece una selección de elementos esenciales, a juicio de sus autores, especialistas en cada una de las materias, encuadrados en la Sección Juvenil de la Asociación Española de Derecho del Trabajo y de la Seguridad Social. En él, conforme a la organización de dicha Sección en grupos de trabajo, se abordan las novedades más relevantes en materia de derechos fundamentales inespecíficos, contratación laboral, vicisitudes del contrato de trabajo, Derecho colectivo, conciliación y corresponsabilidad, protección social y prevención de riesgos laborales. This paper tries to show some of the many changes and novelties in Spanish Labour Law during 2013, drawing up a record of the unstoppable character of our Labour legal system. This report offers a selection of essential elements, according to its authors, all of them specialists in each one of the subjects, being part of the Young Scholars’ Section of the Spanish Association for Labour and Social Security Law. According to the organization of the said Section in working groups, we can find novelties concerning unspecific fundamental rights, work contracts, the life of the work contract and collective Labour Law, reconciliation and co responsibility, social protection and occupational risk prevention

El derecho del trabajo y de la seguridad social en España en 2014

Este documento intenta reflejar algunos de los principales cambios y novedades del ordenamiento laboral español en 2014, levantando acta de cómo la mutabilidad de nuestro Derecho del Trabajo es imparable. Este informe, consciente de ello, ofrece una selección de elementos esenciales, a juicio de sus autores, especialistas en cada una de las materias, encuadrados en la Sección Juvenil de la Asociación Española de Derecho del Trabajo y de la Seguridad Social. En él, conforme a la organización de dicha Sección en grupos de trabajo, se abordan las novedades más relevantes en materia de derechos fundamentales inespecíficos, contratación laboral, vicisitudes del contrato de trabajo, Derecho colectivo, conciliación y corresponsabilidad, protección social y prevención de riesgos laborales. This paper tries to show some of the many changes and novelties in Spanish Labour Law during 2014, drawing up a record of the unstoppable character of our Labour legal system. This report offers a selection of essential elements, according to its authors, all of them specialists in each one of the subjects, being part of the Young Scholars’ Section of the Spanish Association for Labour and Social Security Law. According to the organization of the said Section in working groups, we can find novelties concerning unspecific fundamental rights, work contracts, the life of the work contract and collective Labour Law, work-life balance and co responsibility, social protection and occupational risk prevention

Oestrous behaviour and development of preovulatory follicles in goats induced to ovulate using the male effect with and without progesterone priming

The objective of the current study was to examine follicular dynamics in goats induced to ovulate by using the male effect with or without progesterone pretreatment. Ten Murciano-Granadina goats were treated with a single dose of 25 mg of progesterone in olive oil on the day of male effect induction (Day 0), whereas ten does remained untreated. Changes in the ovarian follicular population and onset of oestrous behaviour were checked daily from Day 0 to the day on which ovulation was detected by ultrasonography. All of the treated goats and only 20% of control goats (P < 0.001) showed oestrous behaviour between 72 and 96 h after the introduction of bucks. Differences in follicle growth were found between the groups. The control goats exhibiting oestrous behaviour during the first 4 days of ovarian screening and all of the goats treated with progesterone had their preovulatory follicles in growing phase. However, the largest follicles in control does not showing oestrus in these first 4 days were in regressing phase, being necessary for the emergence of new preovulatory follicles from a new follicular wave between Days 6 and 7, for exhibition of oestrous behaviour and subsequent ovulation. In conclusion, the appearance of short luteal phases and delayed ovulation in goats treated with the male effect during seasonal anoestrous depends on the stage of follicle development at the time of buck introduction. A single injection of progesterone stimulates the emergence of a new follicular wave, able to grow and give adequate ovulation after induction of the male effect. © CSIRO 2006

Ultrasonographic screening of the ovulatory process in goats

The objectives of the current trial were to characterize the changes in the ultrasound image of preovulatory follicles at ovulation in does and to determine the usefulness of ultrasonography in studies involving the evaluation of time of ovulation. The study involved 12 goats in which oestrus was synchronized with three prostaglandin F2α, cloprostenol injections. Ultrasonographies were performed every 4h from 48h after the third cloprostenol administration. The presence of at least one preovulatory follicle (mean diameter of 7.8±0.4mm) was found in all the does at the time of the first scan. In comparison to other large diameter non-ovulatory follicles, preovulatory follicles had irregular outlines and diffuse and heterogeneous hypoechogenicity in the antrum, with reverberation artefacts similar to echoic spots and echoic lines in some cases. Occurrence of follicular evacuation and ovulation may be determined by the disappearance of the follicular antrum. The corpus haemorrhagicum was found to consist of a heterogeneous structure (mean diameter of 8.6±0.3mm) with higher echogenicity compared to the preovulatory follicles. On the basis of disappearance of the preovulatory follicle and visualization of increased heterogeneous echogenicity in its site, serial ultrasonographic evaluation was found to be useful in establishing the time of ovulation in goats. However, the similarity in the echoic pattern of the corpus hemorraghicum and the surrounding ovary may complicate the identification of ovulations in isolated observations. © 2003 Elsevier B.V. All rights reserved

Origin and fate of preovulatory follicles after induced luteolysis at different stages of the luteal phase of the oestrous cycle in goats

The effect of day of induced luteolysis on follicle dynamics, oestrus behaviour and ovulatory response in goats was studied by administering cloprostenol on Day 5 (n = 10), Day 11 (n = 10), or Day 16 (n = 10) after detection of oestrus. Stage of the luteal phase affected the interval from cloprostenol injection to onset of oestrus, with behavioural oestrus being observed earlier in goats treated early in the luteal phase (43.4 ± 3.2 h on Day 5 versus 57.0 ± 2.6 h on Day 11 and 56.7 ± 2.7 h on Day 16, P < 0.01). The group treated on Day 5 also tended to have a higher proportion of does which exhibited oestrus behaviour (P = 0.07) and ovulation (P = 0.06). In all the cycles, at least one of the ovulatory follicles arose from antral follicles present in the ovary at cloprostenol injection. In 66.7% of monovular cycles, the ovulatory follicle was the largest follicle on the day of luteolysis. In 33.3% of polyovulatory cycles, one of the ovulatory follicles was the largest one present when cloprostenol was administered. In 80% of polyovulatory cycles, the second ovulatory follicle was present on the day of luteolysis; but in the three remaining cycles, the second ovulatory follicle emerged later. This shows that the largest follicle may not exert dominance over other follicles in the goat. Evaluation of follicular dynamics in different phases of luteal activity in current experiment showed an attenuation of dominance in the mid-luteal period. In does treated early or late in the luteal phase, the number of new growing follicles decreased with time (P < 0.01 and 0.05, respectively), the mean number of follicles reaching 4-5 mm in size also decreased (P < 0.001 and 0.01, respectively) and the number of regressing follicles increased (P < 0.05). These effects did not reach statistical significance in does treated in the mid-luteal phase. © 2004 Elsevier B.V. All rights reserved

New estrus synchronization and artificial insemination protocol for goats based on male exposure, progesterone and cloprostenol during the non-breeding season

This study assesses the effectiveness of a method designed to induce and synchronize ovulation in goats during the non-breeding season, allowing for systematic timed artificial insemination (AI), without the need for prior estrus detection. This method (IMA.PRO2®) induces ovulation through the "male effect" and a single 25 mg dose of progesterone given at the time of buck exposure, and early lysis of the induced corpus luteum by the administration of 75 μg of cloprostenol 9 days later. The method was tested in three separate experiments. In experiment 1, estrus was detected in 87.5% of the treated goats 37.0 ± 1.4 h after cloprostenol administration, with the preovulatory LH surge occurring 40.5 ± 1.6 h after the cloprostenol injection. In experiment 2, data from 503 does revealed no significant differences in fertility rates between two groups inseminated 48 h (65.5 ± 4.0%) or 52 h (63 ± 3.0%) after receiving cloprostenol. In experiment 3, 2184 does, comprising 37 replicate groups on 12 farms, were randomly assigned to two trial subgroups. Does in the first subgroup were treated with the IMA.PRO2® method and goats from the second group were given intravaginal progestagens for 11 days, plus 350 IU of eCG and 75 μg of cloprostenol on Day 9 of this treatment. Goats from both subgroups were cervically inseminated at the same time, 50 h after cloprostenol administration in the first group and 46 h after sponge removal in the second. The pregnancy rate achieved with the new method was 64.6%, significantly higher than the yield observed for the use of progestagens plus eCG (46.8%, P &lt; 0.01). The simple method proposed as an alternative to the use of progestagen-eCG treatment provides good pregnancy rates to AI undertaken at a fixed time point, and reduces the amount of hormone needed to synchronize estrus in the animals. © 2007 Elsevier Inc. All rights reserved

Plasma inhibin A determination at start superovulatory FSH treatments is predictive for embryo outcome in goats

To test whether inhibin A assays can be used for the prediction of yields in embryo programmes in goats, 50 does were treated with 45mg FGA sponges (Chronogest®) for 16 days plus a single dose of 100μg i.m. cloprostenol on Day 14, just before the start of administration of eight doses of 1.25ml of Ovagen™ twice daily for 4 days. At first FSH injection, the number and size of all follicles ≥2mm was assessed by transrectal ultrasound and plasma inhibin A levels were measured by specific dimeric assay. There was a positive correlation between number of follicles ≥6mm (8.8±0.5) and inhibin A levels at first FSH dose (193.2±14.5pg/ml, P<0.05). The mean number of corpora lutea on Day 7 after sponge removal was related to the total number of follicles with a diameter of 2-6mm at the onset of the FSH treatment (15.3±0.7, P<0.05). The total number of embryos recovered was related to the number of follicles with 4-6mm in size (6.2±0.5, P<0.05) and to the inhibin A levels at first FSH dose (P<0.05). These results suggest that follicles ≥4mm are the source of inhibin prior to FSH stimulation and are the main source of oocytes resulting in the number of viable embryos recovered after a superovulatory treatment. Hence, the response to superovulatory treatments in goats in terms of the number of embryos can be predicted from either the population of follicles determined by ultrasound or the plasma inhibin A levels at start of the superovulatory FSH treatment. © 2004 Elsevier Inc. All rights reserved

Effects of ovarian follicular status on superovulatory response of dairy goats to FSH treatment

This study evaluates the response of Murciano-Granadina goats to superovulatory FSH treatments, in terms of number of corpora lutea (CL) and transferable embryos, as well as the variability between replicates and the possible effects of follicular status on superovulatory yields. A total of 169 goats were allocated to nine different groups, and treated with 45 mg fluorogestone acetate (FGA) sponges for 16 days plus a single dose of 100 μg i.m.;cloprostenol on Day 14. The superovulatory treatment in all groups consisted of eight doses of 1.25 ml of Ovagen™, twice daily from 60 h before to 24 h after the removal of the progestagen treatment. In the animals from the last three groups (50 females), all follicles ≥2 mm were evaluated by transrectal ultrasonography at the time of the first FSH injection. The response to the FSH treatment, in all the goats, was 14.3 ± 0.5 corpora lutea, 11.3 ± 0.5 recovered embryos (RE) and 6.8 ± 0.4 viable embryos (VE) per goat. Superovulatory yields varied widely between replicates, with significant differences in number of corpora lutea (P < 0.01), recovered embryos (P < 0.05) and viable embryos (P < 0.01). This variability in response to the superovulatory protocol is related with follicular status of the donor at the beginning of the treatment. The number of corpora lutea was positively correlated with the total number of follicles with a diameter of 2-6mm (P < 0.05; r = 0.826). However, the number of recovered and viable embryos were related to the more limited category of follicles of 4-6 mm in size (6.2 ± 0.5), which could indicate that oocytes from smaller follicles are not fully mature. Current results indicate that ultrasonography can be used as a practical criteria for selection of donor goats, which could avoid the treatment of poor-responding females, and provide a basis for the study of suitable treatments to make ovarian follicular populations uniform. © 2003 Elsevier Science B.V. All rights reserved