A Linear Programming Model for Beef Cattle Production

Koots, K. R. and Gibson, J. P. 1998. Effects of production and marketing circumstances on economic values for beef production traits. Can. J. Anim. Sci. 78: 47-55. The effect of altering production and marketing circumstances on economic values is quantified for a complete beef production system. Absolute and relative economic values were found to vary substantially with large, but realistic fluctuations in prices and costs. In addition, several examples of different management and different genotypes gave markedly different economic values than in the base situation. Also investigated were the effects of rescaling the enterprise to accommodate three alternative limitations; fixed feed available from pasture, fixed dollars available for feed or fixed amount of beef produced. The effects of rescaling were highly dependent on whether or not fixed costs were accounted for. When fixed costs were ignored (corresponding to a small positive profit) the economic value for mature size decreased while that for fertility increased, but other traits were largely unaffected by rescaling. Overall, production circumstances that reduced survival and fertility yielded the largest changes to economic values.

Section: Discussionsupporting

confidence: 73%

“…The effect of alternative genotypes on economic and biological efficiency has also been previously investigated with beef production models (Wilton et al 1974;Bourdon and Brinks 1987;Lamb et al 1992). The impact of the alternative genotypes on economic values, however, was not considered.…”

Section: Discussionmentioning

confidence: 99%

Effects of production and marketing circumstances on economic values for beef production traits

Koots¹,

Gibson²

1998

“…This analysis used the basic LP model described by Wilton et al (1974) For personal use only. Morris and Wilton (1975) …”

Section: Methodsmentioning

confidence: 99%

Effects of Creep Feeding, Mature Cow Weight and Milk Yield on Farm Gross Margins in an Integrated Beef Production Model

Morris¹,

Parkins²,

Wilton³

1976

Self Cite

. Effects of creep feeding, mature cow weight and milk yield on farm gross margins in an integrated beef production model. Can. J. Anim. A linear programming model of integrated beef production was used to determrne the effects of different mature cow weights, levels of potential milk yield and creep feeding on economic efficiency. All biological values for this study were taken from the literature. The criteria for comparison were farm gross margins, defined as the difference between total revenue and total variable costs. The model is integrated in the sense that it includes a cow-calf operation with replacements bred on the farm, a feedlot for steers and surplus heifers, cropping, and the labor and capital required for livestock and cropping. Two management programs for weaning and rearing young calves were considered at each of four levels of farm resources (80 and 120 ha of land, each with one or two hired men). Beef:feed price ratios, the maximal daily dry matter intake for cows and the minimal land available for pasture were also varied.Larger cow sizes always gave larger farm gross margins. At both 5 and l0 kg/day milk yield, the management program that used creep feeding through to weaning at 213 days rather than to 70 days gave smaller farm gross margins ($14,813 and $15,166, compared with $16,836 and $16,052). Conclusions about optimal levels for feeding cows for milk were affected by the management program and by maximal daily dry matter intakes for cows. The minimal level of pasture available did not affect the rankings ofcow sizes with respect to farm gross margins; there was only a I .27a change on the average in the farm gross margins with 40 ha minimal pasture available, compared to the optimal cropping program. The beef:feed price ratio was generally not important to the rankings of cow sizes and milk yield, but it affected the magnitude of differences between cow sizes and between milk yields.Research needs for more detailed data on calf energy requirements, dry matter intakes, production from nursing cows at pasture and for defining optimal management programs were identified.Les auteurs ont utilis6 un moddle de programmation lin6aire de

“…More complex systems are better described by computer modelling. With beef cattle, production models have been developed primarily for comparison of breeds and crosses in different environments (Wilton et al 1974;Bourdon and Brinks 1987;Lamb et al 1992). These beef production models often have limited value for defining economic values for within-breed improvement.…”

mentioning

confidence: 99%

Economic values for beef production traits from a herd level bioeconomic model

Koots¹,

Gibson²

1998

Economic values for beef production traits from a herd level bioeconomic model. Can. J. Anim. Sci. 78: 29-45. A bioeconomic model of an integrated Canadian beef production system was developed to derive economic values for genetic improvement of multiple traits. The breeding objective was assumed to be profit maximization of the integrated enterprise. Sixteen input traits were identified as potentially influencing returns and costs in the system. These were mature size, direct and maternal calving ease (in heifers and cows separately), cow fertility, calf survival, cow survival, peak milk yield, residual post-weaning growth rate, residual feed intake in growing animals, residual feed intake in mature animals, residual slaughter weight and dressing percentage at constant backfat thickness, marbling and lean percentage. Most traits were defined to be functionally independent of each other. Thus, traits related to mature size were redefined as residual traits after accounting for the nonlinear relationships among mature size, growth and feed intake traits following mammalian size scaling rules. The base model, which incorporates average returns and costs under production and marketing systems typical of eastern Canada, is described. Economic values in the base model suggest that calf survival, fertility, residual feed intake, and dressing percentage are of primary economic importance in a purebreeding system. These traits also ranked highly in dam lines and (with the exception of fertility) in sire lines in terminal crossbreeding systems.