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1.
PLoS One ; 17(11): e0277189, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36331962

RESUMO

As a teaching subject, animal welfare is challenging for educators and learners, as was recently shown in a recent survey on the evolution of animal welfare teaching in Europe. Among several suggestions to overcome the current resistance to implementing animal welfare education, we highlight two. The first is that animal welfare education should be based on learner-centred approaches; the second is that it should encompass both animal welfare science and ethics and law. To the best of our knowledge, there are no learner-centred pedagogical approaches that can simultaneously explore scientific and ethical concepts. Furthermore, when exploring ethical concepts within the educational context, there is the additional challenge of being able to depart from discussion and debate to a systematic organization of knowledge. Our work simultaneously addresses these two challenges, presenting the design and implementation of a novel web-based learner-centred pedagogical platform for farm animal welfare teaching. The platform, named ANIPHI, uses the Delphi method's iterative nature as a learning process to generate both reflection and (online) debate among learners. ANIPHI can be used by educators in an online environment, in a classroom environment, or in a combination of the two environments. ANIPHI was developed within the ERASMUS+ ANICARE project and is an open web-based platform for all educators interested in teaching farm animal welfare. Given ANIPHI's flexible and user-friendly nature, the platform simultaneously exposes learners to ethical and scientific concepts in different educational realities, according to the educator's objectives. Furthermore, videos depicting different husbandry practices across different types of animal production and countries are embedded in the platform. These videos are commented on by the farmer himself and by animal scientists, which enriches the learner's experience. Educators across the ANICARE consortium have already successfully tested the ANIPHI platform for different farm animal welfare topics. We conclude this article by presenting one example of using ANIPHI in a real-life educational context, where we discuss some aspects of the design and use of our pedagogical platform.


Assuntos
Bem-Estar do Animal , Aprendizagem , Animais , Técnica Delphi , Europa (Continente) , Ensino
2.
Animals (Basel) ; 10(8)2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32751763

RESUMO

Shortage and refeeding situations lead to switches in metabolic pathways induced by undernutrition and body energy reserve (BR) replenishment cycles. In a 122-d experiment, 36 adult Merinos d'Arles ewes were chosen and first accustomed to diet ingredients (i.e., wheat straw, pelleted alfalfa and sugar beet pulp) and the facility environment for 22 d. Then, ewes were randomly assigned to one of three "diet challenge" treatments during 50 d, (control, underfed and overfed; 12 ewes each) corresponding to 100%, 70% or 160% of energy requirements allowances, respectively. Then, a "refeeding challenge" was applied the last 50 d (i.e., diets adjusted with the same ingredients). An individual monitoring of body weight (BW), body condition score (BCS) and energy metabolism was carried out. The last day, a "ß-adrenergic challenge" was applied. Anabolic or catabolic responses were accompanied by synchronized metabolic regulations, leading to contrasting metabolic and BR profiles. Average BW and BCS were higher and lower in overfed and underfed ewes, respectively, which was proportional to lower and higher BR mobilization dynamics. Higher plasma free fatty acids (FFA) were accompanied by lower blood insulin, leptin and glucose levels. After refeeding, a rebound in BW and BCS were observed, and FFA were drastically reduced in underfed ewes. No differences were detected in plasma FFA at the end of the study, but the lipolytic activity was different and contrasted with the adipose tissue mass.

3.
Reprod Biol Endocrinol ; 13: 6, 2015 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-25604903

RESUMO

BACKGROUND: A short-term increase in food intake and specifically dietary energy can stimulate folliculogenesis and increase ovulation rate in ewes. The mechanism appears to involve the insulin-glucose metabolic system and its interaction with FSH signalling pathways in the granulosa cells of ovarian follicles. This experiment was designed to investigate the interaction between these two systems in the granulosa cells of ovarian follicles. METHODS: Thirty six Ile-de-France ewes were used in this controlled experiment to study the effects of intravenous glucose on folliculogenesis. Eighteen ewes were infused with glucose (10 mM/h for 72 h) from day 8 of the oestrous cycle, while the others (controls) received saline. Ovaries were collected when the infusions ended (luteal phase) or 30 h later and after a luteolytic dose of a PGF2α analogue (follicular phase). Follicles were dissected and granulosa cells and follicular fluid harvested. The blood concentrations of glucose, insulin, oestradiol and FSH were monitored over the experiment. The levels of Aromatase P450 and of the phosphorylated and non-phosphorylated forms of Akt, AMPK and ERK in granulosa cells and the concentration of oestradiol in follicular fluid, were determined. RESULTS: Glucose increased the circulating concentration of glucose (P < 0.05) and insulin (P < 0.05). It also increased the total number of follicles >1.0 mm in diameter (P < 0.05) and small (P < 0.05) follicles (>1.0 to 2.0 mm in diameter) but not medium (>2.0 to 3.5 mm in diameter) or large (>3.5 mm in diameter) follicles. Glucose decreased circulating oestradiol (P < 0.05) but not that of FSH or progesterone. Glucose reduced aromatase P450 (P < 0.05) and decreased the phosphorylation of Akt (P < 0.05), ERK (P < 0.05) and AMPK (P < 0.05) in granulosa cells from oestrogenic follicles. The level of Aromatase P450 was greatest in large oestrogenic follicles and the phosphorylation of Akt (P < 0.05), ERK (P < 0.05) and AMPK (P < 0.05) was lower in small follicles compared to medium and large follicles. CONCLUSIONS: These data suggest that the effect of glucose in small follicles is a direct action of glucose that increases the number of small follicles while the effect of glucose in oestrogenic follicles is an indirect insulin-mediated action.


Assuntos
Glucose/farmacologia , Insulina/metabolismo , Folículo Ovariano/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Administração Intravenosa , Animais , Aromatase/metabolismo , Glicemia/metabolismo , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Líquido Folicular/efeitos dos fármacos , Líquido Folicular/metabolismo , Fase Folicular/efeitos dos fármacos , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Folículo Ovariano/metabolismo , Ovulação/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ovinos
4.
Biol Reprod ; 86(2): 52, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22053094

RESUMO

In sheep, the seasonal patterns of reproductive activity are driven primarily by the annual photoperiodic cycle, but can also respond to other environmental factors, such as nutrition, yet little is known about the mechanisms underlying this interaction. This study was designed to define the interaction between photoperiodic and nutritional cues on seasonal patterns of ovarian activity, and to determine if there is a central interaction between these cues. Groups of Ile-de-France ewes were maintained in two nutritional states (restricted and well fed) under a simulated annual photoperiod of 8-16 h of light per day over two breeding seasons. At the end of the first breeding season, half of the animals of each group were ovariectomized (OVX) and fitted subcutaneously with estradiol implants. Low nutritional status shortened the season of ovarian activity, determined from the pattern of progesterone concentrations, by modifying the timing of seasonal transitions between periods of ovarian activity and anestrus. The same results were observed for the seasonal rhythm of neuroendocrine activity, assessed in the OVX ewes, from the pattern of luteinizing hormone concentrations. These results were then confirmed for neuroendocrine activity induced by a photoperiodic treatment. We conclude that nutrition centrally modulates the interpretation of photoperiod to affect seasonal reproductive transitions. The mechanisms of this interaction are discussed in the paper.


Assuntos
Estado Nutricional/fisiologia , Fotoperíodo , Reprodução/fisiologia , Estações do Ano , Ovinos/fisiologia , Animais , Glicemia/metabolismo , Feminino , Insulina/sangue , Hormônio Luteinizante/sangue , Ovário/fisiologia , Progesterona/sangue
5.
BMC Neurosci ; 12: 76, 2011 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-21801416

RESUMO

BACKGROUND: It is now widely accepted that AMP-activated protein kinase (AMPK) is a critical regulator of energy homeostasis. Recently, it has been shown to regulate circadian clocks. In seasonal breeding species such as sheep, the circadian clock controls the secretion of an endogenous rhythm of melatonin and, as a consequence, is probably involved in the generation of seasonal rhythms of reproduction. Considering this, we identified the presence of the subunits of AMPK in different hypothalamic nuclei involved in the pre- and post-pineal pathways that control seasonality of reproduction in the ewe and we investigated if the intracerebroventricular (i.c.v.) injection of two activators of AMPK, metformin and AICAR, affected the circadian rhythm of melatonin in ewes that were housed in constant darkness. In parallel the secretion of insulin was monitored as a peripheral metabolic marker. We also investigated the effects of i.c.v. AICAR on the phosphorylation of AMPK and acetyl-CoA carboxylase (ACC), a downstream target of AMPK, in brain structures along the photoneuroendocrine pathway to the pineal gland. RESULTS: All the subunits of AMPK that we studied were identified in all brain areas that were dissected but with some differences in their level of expression among structures. Metformin and AICAR both reduced (p < 0.001 and p < 0.01 respectively) the amplitude of the circadian rhythm of melatonin secretion independently of insulin secretion. The i.c.v. injection of AICAR only tended (p = 0.1) to increase the levels of phosphorylated AMPK in the paraventricular nucleus but significantly increased the levels of phosphorylated ACC in the paraventricular nucleus (p < 0.001) and in the pineal gland (p < 0.05). CONCLUSIONS: Taken together, these results suggest a potential role for AMPK on the secretion of melatonin probably acting trough the paraventricular nucleus and/or directly in the pineal gland. We conclude that AMPK may act as a metabolic cue to modulate the rhythm of melatonin secretion.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Aminoimidazol Carboxamida/análogos & derivados , Encéfalo/fisiologia , Ritmo Circadiano/fisiologia , Melatonina/sangue , Metformina/administração & dosagem , Ribonucleotídeos/administração & dosagem , Ovinos/sangue , Aminoimidazol Carboxamida/administração & dosagem , Animais , Encéfalo/efeitos dos fármacos , Ritmo Circadiano/efeitos dos fármacos , Feminino , Infusões Intraventriculares
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