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Eventi e cambiamenti nelle scuole veterinarie italiane durante il periodo napoleonico (1796-1814) = Events and changes in the Italian Veterinary Schools during the Napoleonic period 1796-1814
Full text linkPochi giorni prima della fondazione, a Torino, della prima Scuola veterinaria in Italia (1° settembre 1769), nasceva ad Ajaccio Napoleone Buonaparte (15 agosto 1769). Successivamente, furono costituite anche le Scuole veterinarie di Padova, Ferrara, Milano, Modena, Napoli. Negli anni in cui l’influsso del nascente astro napoleonico si estese progressivamente sulla penisola, dalla prima Campagna militare contro gli Austriaci (1796), alla costituzione del Regno d’Italia (1805), fino poi alla sua destituzione (1814), non fu fondata nessuna nuova scuola veterinaria nei territori controllati dai Francesi; tuttavia, nonostante alcune soppressioni (Padova, Ferrara, Modena) e ridimensionamenti funzionali (Torino), avvennero importanti cambiamenti che interessarono in particolare la Scuola di Milano. Questa venne completamente riorganizzata (ampliamento del corpo docenti, riorganizzazione degli insegnamenti, cambiamento di sede, istituzione del convitto) e divenne l’unica scuola teorico-pratica completa del neonato Regno, paragonabile alle celebri scuole francesi di Lione e di Alfort. In questo processo, durato vari anni (1804-1808), ebbero ruolo fondamentale: Eugenio Beauharnais, viceré d’Italia, Pietro Moscati, presidente del Magistrato centrale di Sanità e direttore generale dell’Istruzione pubblica, il professor Giovanni Pozzi, direttore della Scuola, il professor Louis Leroy, anatomista veterinario di origini francesi. A quest’ultimo si deve anche il primo nucleo di formazione del Museo Anatomico milanese (1808). La rifondazione della Scuola Veterinaria fu inserita in un ampio programma di opere pubbliche pensate per Milano capitale, andando nel contempo a supportare la Cavalleria militare, costantemente impegnata sui territori italiani ed europei. Va ricordato che, durante il periodo napoleonico, si formarono e si diplomarono presso la Scuola Milanese giovani veterinari che sarebbero stati futuri docenti presso altre Scuole, come Tommaso Bonaccioli (Ferrara), Vincenzo Mazza (Pisa; Napoli) e Robert Fauvet (Roma). Caso a parte fu la Scuola di Napoli, dove la rifondazione, ideata da Gioacchino Murat già nel 1812, poté completarsi soltanto dopo la caduta del suo Regno, alla fine del 1815.A few days before the foundation, in Turin, of the first Veterinary School in Italy (1 September 1769), Napoleon Buonaparte was born in Ajaccio (15 August 1769). Later, the Veterinary Schools of Padua, Ferrara, Milan, Modena, Naples were also established. In the following years, when the influence of the rising Napoleonic star progressively extended over the peninsula, from the first military campaign against the Austrians (1796), to the establishment of the Kingdom of Italy (1805), and so to its deposition (1814), no new veterinary school was founded in the territories controlled by the French; however, despite some suppressions (Padua, Ferrara, Modena) and functional downsizing (Turin), important changes were taking place, affecting in particular the School of Milan. This was completely reorganized (expansion of the teaching staff, reorganization of courses, change of seat, institution of the boarding school) and became the only complete theoretical-practical school of the newborn Kingdom, comparable to the famous French schools of Lyon and Alfort. In this process, which lasted several years (1804-1808), the following figures played a fundamental role: Eugene de Beauharnais, Viceroy of Italy, Pietro Moscati, President of the Central Health Magistrate and general Director of Public Education, Professor Giovanni Pozzi, Director of the School, Professor Louis Leroy, French-born veterinary anatomist. The latter was also responsible for the first nucleus of the Milan Anatomical Museum (1808). The re-founding of the Veterinary School was part of a wide-raging program of public works, designed for Milan as the capital city; in the same time it supported the Military Cavalry, constantly engaged in the Italian and European territories. It should be noticed that, during the Napoleonic period, some young veteri narians were trained and graduated from the Milan School who were to become future teachers at other schools, such as Tommaso Bonaccioli (Ferrara), Vincenzo Mazza (Pisa; Naples) and Robert Fauvet (Rome). The School of Naples was a separate case, because its re-foundation, conceived by Joachim Murat as early as 1812, could only be completed after the fall of his Kingdom, at the end of 1815
Influence of different stages of the oestrous cycle on cumulus-oocyte communications in canine oocytes : effects on the efficiency of in vitro maturation
No full textThe aim of this study was to investigate the effects of different stages of the oestrous cycle on the communications between dog oocytes and cumulus cells, as well as their possible relationships with the meiotic competence of oocytes matured in vitro. Ovaries were harvested from bitches undergoing anoestrus or late pro-oestrus. Maturation of cumulus-oocyte complexes (COCs) was performed in TCM-199 with 0.3% (w/v) BSA, 0.5 iu FSH ml-1 and 0.5 iu LH ml-1 for 72 h. At the time of collection (0 h), and after 24, 48 or 72 h of culture, some oocytes were stained with Lacmoid to evaluate the nuclear stage of maturation. At 0, 24 or 48 h of in vitro maturation (IVM), oocytes were microinjected (n = 84) with a 3% (w/v) Lucifer yellow solution to evaluate the presence of cumulus-oocyte communications through gap junctions. At t = 0, communications were open in 89% of COCs collected during late pro-oestrus, whereas such communications were not evident in any of the oocytes collected during anoestrus. Communications remained permeable for the first 24 h of maturation in many late pro-oestrous oocytes (67%), whereas no fluorescence diffusion was observed at 48 h of maturation. The presence of cumulus-oocyte communications in late pro-oestrous oocytes was accompanied by their ability to resume meiosis and reach telophase I or metaphase II at higher rates than in oocytes collected during anoestrus (11.1% versus 0%, respectively; P < 0.01). These results indicate that, during anoestrus, there are no permeable gap junctions between oocytes and surrounding cumulus cells at the time of isolation from the ovary. This finding indicates that such oocytes are unsuitable for IVM, as confirmed by their inability to reach telophase I or metaphase II in culture. In contrast, a positive correlation was observed between the presence of permeable gap junctions and meiotic competence in COCs isolated at late pro-oestrus. However, the small proportion of oocytes reaching telophase I and metaphase II indicates that further efforts to define better culture conditions are still required
ROLE OF THE OVIDUCT DURING EARLY EMBRYOGENESIS
No full textA large number of studies suggests that the oviduct exerts an important role in early embryonic development but its nature is far from being elucidated. At present embryotrophic action seems to be based upon the interaction between the embryo and various groups of molecules. These include (a) specific proteins secreted by the epithelium of restricted oviduct regions; (b) growth factors normally present also in other districts of the organism, whose ligand and receptors genes are often expressed both in the oviduct and in the embryo, (c) various metabolites, such as glucose, oxygen and free radicals scavengers, which determine the environment where the developmental potential of fertilized eggs can be fully expressed. These groups of substances will be examined in some details giving particular emphasis to most recent acquisitions
Defective developmental capacity of bovine oocytes is accompanied by a shorte poly-(A) tail of maternal trascripts
No full textCumulus-oocyte communications during in vitro maturation in the horse : effects of season and estrous mare serum
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Different mitogenic capabilities of small and large granulosa cells isolated from bovine follicles
No full textFemale rainbow trout (Oncorhynchus mykiss) produce a single batch of eggs each year; synchronous growth of oocytes, all of which are ovulated at the same time, occurs in the two ovaries. To examine the regulatory mechanisms controlling egg size and number, virgin female rainbow trout were subjected to unilateral ovariectomy (ULO) during early vitellogenesis, and oocyte recruitment and growth in the remaining ovary were monitored. The study also set out to determine whether the presence of a second population of smaller oocytes in the maturing pool (induced by ULO) affected the timing of ovulation and/or the size of the eggs ovulated. Two months after ULO, there was no difference in the gonadosomatic index between ULO fish and controls. Compensatory ovarian hypertrophy resulted from the recruitment of a second population of primary oocytes into the vitellogenic pool. This population of smaller maturing oocytes in the ULO fish displayed growth rates up to twice those of the population of larger oocytes in the same ovary and of oocytes in controls. The growth rate of the population of larger oocytes in the ULO fish was not altered by the recruitment of a second maturing population. One month after ULO, fish had a lower concentration of plasma estradiol-17beta; than did controls; subsequently the concentrations of plasma estradiol-17β in the ULO and control groups were similar. After ULO, plasma levels of vitellogenin in the ULO fish did not differ from those in the control group throughout the study. At or close to ovulation, the fecundity of ULO fish was 75-80% that of controls. In the control group, oocytes appeared to reach a certain critical size before they were ovulated, and fish with higher fecundity ovulated later than their less fecund counterparts. ULO did not affect the timing of ovulation, and ULO fish ovulated eggs with a considerably greater size-range than did controls
Embryonic development of denuded bovine oocytes matured in the presence of intact cumulus-oocyte complexes
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Identification and characterization of a PDGF-like peptide amongst bovine oviduct secretions
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