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1.
Dalton Trans ; 52(19): 6457-6472, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37092684

RESUMO

Receptor L, composed of a tripropylenetetramine chain linking the 2 and 7 positions of an acridine unit via methylene bridges, behaves as a pentaprotic base in aqueous solution. The first four protonation steps occur on the tetra-amine chain, while the acridine nitrogen protonates only below pH 4. The penta-protonated receptor assumes a folded conformation, resulting in a cleft delimited by the aliphatic tetramine and acridine moieties, in which anions of appropriate size can be hosted. Potentiometric titrations reveal that F- forms the most stable complexes, although the stability constants of the Cl- and Br- adducts are unusually only slightly lower than those observed for F- complexes. A remarkable drop in stability is observed in the case of I- adducts. Oxo-anions, including H2PO4-, NO3- and SO42-, are not bound or weakly bound by the protonated receptor, despite the known ability of charged oxygens to form stable O-⋯HN+ salt bridges. This unexpected stability pattern is explained in the light of the X-ray crystal structures of H5LCl5·4H2O, H5LBr5·4H2O, H5L(NO3)5·3H2O and H5L(H2PO4)5·(H3PO4)2·4H2O complexes, coupled with MD simulations performed in the presence of explicit water molecules, which reveal that Cl- and, overall, Br- possess the optimal size to fit the receptor cleft, simultaneously forming strong salt bridging interactions with the ammonium groups and anion⋯π contacts with protonated acridine. I- and oxo-anions are too large to conveniently fit the cavity and are only partially enclosed in the receptor pocket, remaining exposed to solvent, with a lower entropic stabilization of their complexes. Although F- could be enclosed in the cavity, its smaller size favours the F-⋯HN+ salt bridging interaction from outside the receptor pocket. The fluorescence emission of the acridinium unit is quenched by anion binding. The quenching ability parallels the stability of the complexes and is related to the relevance of the anion⋯π contacts in the overall host-guest interaction.

2.
Animal ; 17(5): 100794, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37121159

RESUMO

The transition to a more sustainable livestock sector represents one of the major challenges of our time. Life Cycle Assessment (LCA) is recognised as the gold standard methodology for assessing the environmental impact of farming systems. Simultaneously, animal welfare is a key component of livestock production and is intrinsically related to human and environmental well-being. To perform an overall on-farm sustainability assessment, it would be desirable to consider both the environmental impact and the welfare of the animals. The present work aimed to summarise and describe the methodologies adopted in peer-reviewed papers published to date, that combine animal welfare evaluation with LCA. Citations, retrieved from four bibliographical databases, were systematically evaluated in a multi-stage approach following the JBI and PRISMA scoping review guidelines. The searches identified 1 460 studies, of which only 24 were compliant with the inclusion criteria. The results highlighted how the environmental LCA was undertaken with a much more homogenous and standardised method than animal welfare assessment. When studies were grouped based on the type of animal welfare assessment performed: 16.7% used single welfare indicators, 45.8% multiple indicators, 8.3% applied existing validated protocols (i.e., TGI-200 and TGI-35L), 16.7% used non-validated protocols and 12.5% employed other methods. The papers were further classified with respect to the "5 Animal Welfare Domains Model": the most assessed domain was "environment" (90.5% of the papers%), followed by "health" (52.4%), "nutrition" (33.3%), "behavioural interactions" (28.6%) and "mental state" (9.5%). None of the studies assessed all the domains simultaneously. In addition, 66.7% of papers (n = 16) aggregated the animal welfare indicators into a final score. Within these, only four papers proposed to associate the animal welfare scores with the LCA functional unit. An overall sustainability score, calculated with several different approaches to summarise the information, was provided by 46% of the papers. In summary, despite the topic's relevance, to date, there is neither a consensus on the animal welfare assessment approach to be carried out (indicators selection and their aggregation) nor on the standardisation of an integrated animal welfare-LCA evaluation. The present review provides a basis for the development of common future guidelines to carry out a comprehensive, true-to-life and robust farm sustainability assessment.


Assuntos
Agricultura , Meio Ambiente , Humanos , Animais , Fazendas , Bem-Estar do Animal , Gado , Estágios do Ciclo de Vida
3.
Animal ; 15(3): 100143, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33518488

RESUMO

Precision livestock farming (PLF) technologies are becoming increasingly common in modern agriculture. They are frequently integrated with other new technologies in order to improve human-livestock interactions, productivity and economical sustainability of modern farms. New systems are constantly being developed for concentrated farming operations as well as for extensive and pasture-based farming systems. The development of technologies for grazing animals is of particular interest for the Mediterranean extensive sheep farming sector. Dairy sheep farming is a typical production system of the area linked to its historical and cultural traditions. The area provides roughly 40% of the world sheep milk, having 27% of the milk-producing ewes. Developed countries of the area (France, Italy, Greece and Spain - FIGS) have highly specialized production systems improved through animal selection, feeding techniques and intensification of production. However, extensive systems are still practiced alongside intensive ones due to their lower input costs and better resilience to market fluctuations. In the current article, we evaluate possible PLF systems and their suitability to be incorporated in extensive dairy sheep farming as practiced in the FIGS countries. Available products include: electronic identification systems (now mandatory in the EU) such as ear tags, ruminal boluses and sub-cutaneous radio-frequency identification; on-animal sensors such as accelerometers, global positioning systems and social activity loggers; and stationary management systems such as walk-over-weights, automatic drafter (AD), virtual fencing and milking parlour-related technologies. The systems were considered according to their suitability for the management and business model common in dairy sheep farming. However, adoption of new technologies does not take place immediately in small and medium scale extensive farming. As sheep farmers usually belong to more conservative technology consumers, characterized by an average age of 60 and a very transparent community, the dynamics do not favour financial risk taking involved with new technologies. Financial barriers linked to production volumes and resource management of extensive farming are also a barrier for innovation. However, future prospectives could increase the importance of technology and promote its wider adoption. Trends such as global sheep milk economics, global warming, awareness to animal welfare, antibiotics resistance and European agricultural policies could influence the farming practices and stimulate wider adoption of PLF systems in the near future.


Assuntos
Agricultura , Gado , Animais , Indústria de Laticínios , Fazendas , Feminino , França , Grécia , Itália , Ovinos , Espanha
4.
J Dairy Sci ; 104(1): 750-761, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33131814

RESUMO

Difficult calving may adversely affect dairy cow health and performance. Maternal:fetal disproportion is a major cause of dystocia. Therefore, the main objective of this study was to assess the effects of dam:calf body weight ratio (D:C) on calving difficulty, rumination time, lying time, and inflammatory profile in 25 Holstein dairy cows. Using automatic monitoring systems, we monitored behavior and production in 9 primiparous and 16 pluriparous cows between dry-off and 30 d in milk. During the same period, we collected blood samples to monitor metabolism and inflammatory profile of these cows. Calvings were video recorded to assess calving difficulty and observe the duration of the expulsive stage. After parturition, the cows were separated into 3 classes according to their D:C: easy (E; D:C >17), medium (M; 14 < D:C <17), and difficult (D; D:C <14). The cows in class D showed relatively longer labor durations (108 min vs. 54 and 51 min for classes D, M, and E, respectively) and higher calving assistance rates (50% vs. 0 and 11% of calvings for classes D, M, and E, respectively) than those in the other 2 classes. Compared with the cows in classes M and E, those in class D exhibited shorter rumination times on the day of calving (176 min/d vs. 288 and 354 min/d for classes D, M, and E, respectively) and during the first week of lactation (312 min/d vs. 339 and 434 min/d for classes D, M, and E, respectively) and maintained lower rumination values until 30 DIM (399 min/d vs. 451 and 499 min/d for classes D, M, and E, respectively). Primiparous class D cows had shorter resting times during the first week after calving compared with those in class M (8 vs. 11 h/d for classes D and M, respectively). Interclass differences were found in terms of the levels of inflammation markers such as acute-phase proteins (ceruloplasmin, albumin, retinol, and paraoxonase). Moreover, cows in class D had lower plasma levels of fructosamine and creatinine after calving. Low D:C reduced postcalving rumination time and increased inflammation grade, suggesting a lower welfare of these animals at the onset of lactation. The D:C might serve as a useful index for the identification of cows at relatively higher risk of metabolic and inflammatory disease, thus helping farmers and veterinarians improve the welfare and health of these cows.


Assuntos
Doenças dos Bovinos/etiologia , Inflamação/veterinária , Parto , Complicações na Gravidez/veterinária , Ruminação Digestiva , Animais , Bovinos , Feminino , Inflamação/etiologia , Lactação , Leite , Gravidez , Fatores de Tempo
5.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1862(9): 1013-1023, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28647405

RESUMO

Docosahexaenoic acid (DHA) is an essential omega-3 fatty acid known to be neuroprotective in several models of human diseases, including multiple sclerosis. The protective effects of DHA are largely attributed to its ability to interfere with the activity of transcription factors controlling immune and inflammatory responses, including the agonist-dependent transcription factor peroxisome proliferator-activated receptor-γ (PPAR-γ). In this study, we used primary oligodendrocyte progenitor (OP) cultures from neonatal rat brain to investigate whether DHA could influence OP maturation and directly promote myelination, as previously reported for selective PPAR-γ agonists. We show that, similarly to the selective PPAR-γ agonist pioglitazone (PGZ), DHA promotes OP maturation and counteracts the maturational arrest induced by TNF-α, used to mimic inflammatory conditions. The PPAR-γ antagonist GW9662 prevented both DHA-induced OP maturation and PPAR-γ nuclear translocation, supporting the hypothesis that DHA acts through the activation of PPAR-γ. In addition, both PGZ and DHA induced the phosphorylation of extracellular signal-regulated-kinase 1-2 (ERK1/2), in a PPAR-γ-dependent manner. ERK1/2 activity is known to regulate the transition from OPs to immature oligodendrocytes and the presence of specific inhibitors of ERK1/2 phosphorylation (U0126 or PD98059) prevented the differentiating effects of both DHA and PGZ. These results indicate that DHA might influence the process of OP maturation through its PPAR-γ agonistic activity and provide novel molecular mechanisms for the action of this dietary fatty acid, further supporting the nutritional intervention in demyelinating diseases such as multiple sclerosis.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/farmacologia , Oligodendroglia/efeitos dos fármacos , PPAR gama/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Doenças Desmielinizantes/metabolismo , Ácidos Graxos Ômega-3/farmacologia , Inflamação/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Oligodendroglia/metabolismo , Oligodendroglia/fisiologia , Fosforilação/efeitos dos fármacos , Pioglitazona , Ratos , Ratos Wistar , Tiazolidinedionas/farmacologia , Fatores de Transcrição/metabolismo
6.
Meat Sci ; 86(2): 474-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20570623

RESUMO

The aim of this study was to evaluate the effects of the rearing season (autumn vs winter) on the carcass and meat quality of light lambs, obtained according to the traditional farming system usual in central Italy. Eighty carcasses from 60 d+/-3 old unweaned Apennine single birth male lambs, permanently reared indoor, half in autumn (receiving milk from ewes permanently pastured) and half in winter (which dams did never acceded to pasture), were weighed, classified according to the EU classification system for light lambs, and their Longissimus lumborum meat was analysed for pH, colour, drip and cooking losses, proximate composition and fatty acids profile of intramuscular fat. Most of the carcasses fully responded to the 1st quality EU requirements and no effects of the rearing season was evident on carcass characteristics. On the contrary, L. lumborum of lambs born and reared in autumn, receiving milk from ewes permanently pastured, evidenced a lower Lightness L* (P=0.02), a higher Chroma C* (P=0.01), with a higher fat content (P=0.04) than lambs reared in winter, which dams were permanently stall-fed. Moreover the intramuscular fat of the former was characterized by a greater PUFA concentration (P=0.01), a more favourable n-6/n-3 ratio (P<0.001), and a higher CLA content (P<0.001) than the latter, as a result of the difference related to the sheep traditional feeding system.


Assuntos
Tecido Adiposo/química , Dieta , Ácidos Graxos/análise , Tecnologia de Alimentos , Carne/normas , Músculo Esquelético/química , Estações do Ano , Ração Animal , Animais , Cadáver , Cor , Gorduras na Dieta/análise , Feminino , Itália , Masculino , Poaceae , Ovinos
7.
Meat Sci ; 85(1): 33-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20374861

RESUMO

The effects of different loading methods on the welfare, carcass characteristics and meat quality traits of hybrid commercial rabbits were investigated. 384 male rabbits, 82 days old, were transported from the farm to the slaughterhouse. At the farm, 192 rabbits were loaded onto the truck smoothly (S) and 192 rabbits were loaded roughly (R). The S loading method consisted of carefully placing each rabbit into the transport crates. In the R method, the loading was hurriedly and carelessly executed by the transport operator, throwing each animal into the crates fixed on the truck. Live weight before and after transport as well as slaughter data were recorded for each rabbit, and a subset of 80 carcasses were evaluated for meat quality. Blood samples from 80 rabbits were analysed for haematological and biochemical parameters. A significant neutrophilia (P<0.001), lymphocytopaenia (P<0.001) and an increase in serum aspartate aminotransferase (AST) (P<0.01), alanine aminotransferase (ALT) (P<0.001) and creatine kinase (CK) activities (P<0.001) were recorded in all rabbits after transport, independent of the loading method. A twofold increase in serum corticosterone concentration (6.23 vs. 14.88 ng/mL; P=0.001) was observed in all rabbits following transport. Results suggest that the stress parameters analysed were more influenced by transport and handling itself rather than by the different loading methods. The results showed that there was no adverse effect of loading method on carcass traits. Furthermore, the stress condition evidenced by haematological and biochemical parameters prior to slaughter did not affect meat quality.


Assuntos
Matadouros , Criação de Animais Domésticos , Bem-Estar do Animal , Corticosterona/sangue , Carne/normas , Estresse Psicológico/sangue , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Cadáver , Creatina Quinase/sangue , Manobra Psicológica , Hematologia , Linfopenia , Masculino , Neutrófilos , Coelhos , Meios de Transporte/métodos
8.
Meat Sci ; 81(4): 678-85, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20416571

RESUMO

Objective of this study was to evaluate the performance, the quality and oxidative stability of meat, the total Se and specific selenoamino-acids content of muscle of lambs that were fed diets supplemented from different Se sources and at different levels. Forty-eight Apennine lambs 30day old (12.78±0.94kg) received, during a 63day period, a total mixed ration (TMR) which was either Se unsupplemented (Control group - background only- 0.13mg/kg Se) or supplemented with Na selenite (0.30mg/kg Se as sodium selenite) or selenium enriched yeast (0.30mg/kg and 0.45mg/kg Se as Se-yeast). Growth performance, feed to gain ratio, carcass and meat quality (pH, drip and cooking losses, colour, GSH-Px activity and chemical analysis) did not show any difference between the treatments. Meat colour and oxidative stability during 9 days of refrigerated storage were unaffected by dietary supplementation, suggesting that, at the levels of Se used in this experiment, dietary Se, even from an organic source, had limited potential for reducing lipid oxidation. Selenium supplementation raised the Se content in muscle (P<0.001) with the greatest increase when Se-yeast was fed. Although selenite increased total Se, it did not influence total or specific selenoamino-acids in this tissue. On the contrary, Se-yeast supplementation led to an increase in muscle Se-methionine content. We conclude that Se supplementation can increase significantly muscle Se levels and produce, particularly when Se-yeast is fed, a source of Se enriched meat as Se-methionine.

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