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1.
Sci Total Environ ; 946: 174240, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-38925383

RESUMEN

Medium-scale pig production systems, which make up 30 % of Mexico's pig farms, face two key obstacles impacting their economic and financial performance. The first is the absence of a sales plan based on pigs' weight, which negatively affects both profitability and resource management. The second obstacle is inadequate waste management, which hampers efforts to mitigate environmental impacts generated by pig farms. Based on this criterion, this study aims to determine technical and economic optimum levels of a medium-scale pig farm and evaluate its associated environmental impacts. Based on the last farm sale weight (116.3 kg - base scenario), technical and economic optimum levels were estimated using a production function, resulting in a technical optimum of 155 kg and an economic optimum of 127 kg. An environmental assessment of the pig fattening process was carried out following the principles of the Life Cycle Analysis methodological framework. Using a cradle-to-farm gate perspective, and establishing 1 kg of live-weight pig as the functional unit. The results indicated that production at maximum weight level (155 kg), increased environmental impacts by 60 % to 75 % compared to the base scenario. In contrast, at the maximum economic benefit level (127 kg), environmental impacts increased by 5 % to 10 %. Feed production represented the largest contribution (over 74 %) in six impact categories. The results provide valuable information for medium-scale pig farms to mitigate the environmental burdens associated with the optimal production weight and to direct efforts towards achieving future economic and environmental efficiency.


Asunto(s)
Crianza de Animales Domésticos , Ambiente , Animales , México , Crianza de Animales Domésticos/métodos , Porcinos , Granjas
2.
PLoS One ; 19(5): e0298897, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38722980

RESUMEN

To estimate the economic and financial viability of a pig farm in central sub-tropical Mexico within a 5-year planning horizon, a Monte Carlo simulation model was utilized. Net returns were projected using simulated values for the distribution of input and product processes, establishing 2021 as base scenario. A stochastic modelling approach was employed to determine the economic and financial outlook. The findings reveal a panorama of economic and financial viability. Net income increased by 555%, return on assets rose from 3.36% in 2022 to 11.34% in 2026, and the probability of decapitalization dropped from 58% to 13%, respectively in the aforesaid periods. Similarly, the probability of obtaining negative net income decreased from 40% in 2022 to 18% in 2026. The technological, productive, and economic management of the production unit allowed for a favorable scenario within the planning horizon. There is a growing interest in predicting the economic sectors worth investing in and supporting, considering their economic and development performance. This research offers both methodological and scientific evidence to demonstrate the feasibility of establishing a planning schedule and validating the suitability of the pork sector for public investment and support.


Asunto(s)
Granjas , México , Animales , Porcinos , Granjas/economía , Modelos Económicos , Crianza de Animales Domésticos/economía , Método de Montecarlo , Estudios Prospectivos , Renta
3.
Mol Biosyst ; 11(11): 2964-77, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26282280

RESUMEN

Unbalanced uptake of Omega 6/Omega 3 (ω-6/ω-3) ratios could increase chronic disease occurrences, such as inflammation, atherosclerosis, or tumor proliferation, and methylation methods for measuring the ruminal microbiome fatty acid (FA) composition/distribution play a vital role in discovering the contribution of food components to ruminant products (e.g., meat and milk) when pursuing a healthy diet. Hansch's models based on Linear Free Energy Relationships (LFERs) using physicochemical parameters, such as partition coefficients, molar refractivity, and polarizability, as input variables (Vk) are advocated. In this work, a new combined experimental and theoretical strategy was proposed to study the effect of ω-6/ω-3 ratios, FA chemical structure, and other factors over FA distribution networks in the ruminal microbiome. In step 1, experiments were carried out to measure long chain fatty acid (LCFA) profiles in the rumen microbiome (bacterial and protozoan), and volatile fatty acids (VFAs) in fermentation media. In step 2, the proportions and physicochemical parameter values of LCFAs and VFAs were calculated under different boundary conditions (cj) like c1 = acid and/or base methylation treatments, c2 = with/without fermentation, c3 = FA distribution phase (media, bacterial, or protozoan microbiome), etc. In step 3, Perturbation Theory (PT) and LFER ideas were combined to develop a PT-LFER model of a FA distribution network using physicochemical parameters (V(k)), the corresponding Box-Jenkins (ΔV(kj)) and PT operators (ΔΔV(kj)) in statistical analysis. The best PT-LFER model found predicted the effects of perturbations over the FA distribution network with sensitivity, specificity, and accuracy > 80% for 407 655 cases in training + external validation series. In step 4, alternative PT-LFER and PT-NLFER models were tested for training Linear and Non-Linear Artificial Neural Networks (ANNs). PT-NLFER models based on ANNs presented better performance but are more complicated than the PT-LFER model. Last, in step 5, the PT-LFER model based on LDA was used to reconstruct the complex networks of perturbations in the FA distribution and compared the giant components of the observed and predicted networks with random Erdos-Rényi network models. In short, our new PT-LFER model is a useful tool for predicting a distribution network in terms of specific fatty acid distribution.


Asunto(s)
Simulación por Computador , Ácidos Grasos/metabolismo , Animales , Bacterias/metabolismo , Catálisis , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Volátiles/análisis , Masculino , Metilación , Microbiota , Rumen/microbiología , Ovinos
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