Analysis of feeding strategies for small-scale
dairy systems in central Mexico using linear
programming

Val-Arreola, D.; Kebreab, E.; Mills, J.A.N.

doi:10.22358/jafs/67138/2005

Cited by 5 publications

(3 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Markov chain model suggested adopting different reproduction strategies according to period of the year in which the cow was expected to calve. Third, they conducted an analysis of feeding strategies for small-scale dairy systems by using LP (Val-Arreola et al, 2005). The study recommended an improvement in forage quality to increase efficiency, rather than increasing concentrate supplementation, as a viable strategy.…”

Section: Nutrient Utilization At the Animal And Whole-farm Levelsmentioning

confidence: 99%

Recent advances in modeling nutrient utilization in ruminants1

Kebreab

Dijkstra

Bannink

2009

Journal of Animal Science

Self Cite

View full text Add to dashboard Cite

Mathematical modeling techniques have been applied to study various aspects of the ruminant, such as rumen function, postabsorptive metabolism, and product composition. This review focuses on advances made in modeling rumen fermentation and its associated rumen disorders, and energy and nutrient utilization and excretion with respect to environmental issues. Accurate prediction of fermentation stoichiometry has an impact on estimating the type of energy-yielding substrate available to the animal, and the ratio of lipogenic to glucogenic VFA is an important determinant of methanogenesis. Recent advances in modeling VFA stoichiometry offer ways for dietary manipulation to shift the fermentation in favor of glucogenic VFA. Increasing energy to the animal by supplementing with starch can lead to health problems such as subacute rumen acidosis caused by rumen pH depression. Mathematical models have been developed to describe changes in rumen pH and rumen fermentation. Models that relate rumen temperature to rumen pH have also been developed and have the potential to aid in the diagnosis of subacute rumen acidosis. The effect of pH has been studied mechanistically, and in such models, fractional passage rate has a large impact on substrate degradation and microbial efficiency in the rumen and should be an important theme in future studies. The efficiency with which energy is utilized by ruminants has been updated in recent studies. Mechanistic models of N utilization indicate that reducing dietary protein concentration, matching protein degradability to the microbial requirement, and increasing the energy status of the animal will reduce the output of N as waste. Recent mechanistic P models calculate the P requirement by taking into account P recycled through saliva and endogenous losses. Mechanistic P models suggest reducing current P amounts for lactating dairy cattle to at least 0.35% P in the diet, with a potential reduction of up to 1.3 kt/yr. A model that integrates nutrient utilization and health has great potential benefit for ruminant nutrition research. Finally, whole-animal or farm level models are discussed. An example that used a multiple-criteria decision-making framework is reviewed, and the approach is considered to be appropriate in dealing with the multidimensional nature of agricultural systems and can be applied to assist the decision process in cattle operations.

show abstract

Section: Nutrient Utilization At the Animal And Whole-farm Levelsmentioning

confidence: 99%

Recent advances in modeling nutrient utilization in ruminants1

Kebreab

Dijkstra

Bannink

2009

Journal of Animal Science

Self Cite

View full text Add to dashboard Cite

show abstract

“…New approaches are required to provide insights into improving the efficiency of this type of system. Previous work has suggested considering changes related to: i) selecting the most appropriate feeding strategy according to resource availability and herd needs (Val-Arreola et al, 2005); ii) deciding the number of cows calving in each period of the year (Val-Arreola et al, 2004a); and iii) selecting the best forage production strategy (Val-Arreola et al, 2004b). The previous work, however, considered different aspects of the system in isolation, unlike the current study, which considers the system holistically, leading to more specific recommendations.…”

Section: Introductionmentioning

confidence: 95%

Modeling Small-Scale Dairy Farms in Central Mexico Using Multi-Criteria Programming

Val-Arreola

Kebreab

France

2006

Journal of Dairy Science

Self Cite

View full text Add to dashboard Cite

Milk supply from Mexican dairy farms does not meet demand and small-scale farms can contribute toward closing the gap. Two multi-criteria programming techniques, goal programming and compromise programming, were used in a study of small-scale dairy farms in central Mexico. To build the goal and compromise programming models, 4 ordinary linear programming models were also developed, which had objective functions to maximize metabolizable energy for milk production, to maximize margin of income over feed costs, to maximize metabolizable protein for milk production, and to minimize purchased feedstuffs. Neither multi-criteria approach was significantly better than the other; however, by applying both models it was possible to perform a more comprehensive analysis of these small-scale dairy systems. The multi-criteria programming models affirm findings from previous work and suggest that a forage strategy based on alfalfa, ryegrass, and corn silage would meet nutrient requirements of the herd. Both models suggested that there is an economic advantage in rescheduling the calving season to the second and third calendar quarters to better synchronize higher demand for nutrients with the period of high forage availability.

show abstract

“…Linear Programming. This is the field of mathematical optimization dedicated to maximizing or minimizing (optimizing) a linear function called the objective function; the variables of said function are subject to a series of restrictions expressed through a system of equations or inequalities that are also linear (Val-Arreola et al, 2005). Net Exports.…”

Section: Glossarymentioning

confidence: 99%

Global Oil Industry Efficiency and Productivity in the Upstream Sector

Ortiz Villegas,

Alcaraz Vera

2024

View full text Add to dashboard Cite

The book addresses a crucial issue regarding the economic development of countries. The structure of the oil industry -and in particular the upstream sector, responsible for the exploration and extraction of hydrocarbons- maintains a strategic value, since a large part of the energy sovereignty of each region depends on it; the income it generates in the local and international markets affects the economic performance variables of companies and populations around the world. In this scenario, the work presented is focused on diagnosing the efficient performance of the upstream sector of each economy and on finding out whether total factor productivity means that the economy has progressed technologically and has improved the efficiency in the use of its resources, thus achieving an increase in its production by improving the combination of its factors and its production processes. This book is a valuable input for the design and implementation of a national public energy policy for the operations of the state-owned company Petróleos Mexicanos (Pemex), since it provides a tool to evaluate the role of efficiency and technological change in the productivity of the factors used, with the purpose of improving its processes and identifying the moments when it is reduced, thus being able to react in time to formulate more realistic objectives and determine the factors that contribute to improve it.

show abstract

Analysis of feeding strategies for small-scale dairy systems in central Mexico using linear programming

Cited by 5 publications

References 17 publications

Recent advances in modeling nutrient utilization in ruminants1

Recent advances in modeling nutrient utilization in ruminants1

Modeling Small-Scale Dairy Farms in Central Mexico Using Multi-Criteria Programming

Global Oil Industry Efficiency and Productivity in the Upstream Sector

Contact Info

Product

Resources

About