IMPACTS OF PST ON OPTIMAL PRODUCTION AND MARKETING DECISIONS OF A GROW-FINISH HOG FARM OPERATION

This paper examines the impact of PST on the optimal production/marketing decisions of a grow-finish hog farm operation. The analysis evaluates PST from three angles: the feed efficiency effect, the leaner meat price effect, and the aggregate-supply-induced price effect. When limited to the feed efficiency effect only, the primary response to the new technology is to increase the animal turnover rate of the operation. When the leaner meat price effect is also included, marketing weight increases while turnover rate remains relatively unchanged. Additionally, if the increased aggregate supply depressed the market price by more than 10%, the benefits from improved feed efficiency and learner meat will be completely dissipated. Aggregate price adjustments (reductions) of less than 10 percent maintained positive producer benefits resulting from improved feed efficiency and leaner meat.Livestock Production/Industries,

Genetics of feed intake and efficiency in grazing dairy cows : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science

Feed efficiency in dairy cows is widely acknowledged as a highly desirable characteristic to improve because of its well-documented impact on production costs. Traditional measures of feed efficiency have used ratio traits, specifically energy conversion efficiency, but these have undesirable statistical properties. Alternative measures of feed efficiency are those based on the residuals from regression-type statistical models, the most common of which is residual energy intake (REI). Residual energy intake is defined as the difference between actual and predicted intake and is usually derived from least squares regression models. The general objective of this thesis was to quantify phenotypic and genetic (co)variances between the feed intake complex, performance, and fertility traits in lactating Holstein-Friesian dairy cows. A total of 8,199 feed intake records from 2,693 lactations on 1,412 grazing lactating Holstein-Friesian dairy cows from experimental farms were used. Several alternative efficiency definitions were developed, each with their own respective strengths and weaknesses. Exploitable genetic variation was demonstrated to exist for the range of alternative efficiency traits, and the magnitude of this variation was sufficiently large to justify consideration of the feed efficiency complex in future dairy breeding goals. The heritability estimates for the different efficiency traits estimated using repeatability models varied from 0.06 to 0.21. Variance components, however, differed across lactation when estimated using random regression models; for example, the heritability of REI varied from 0.04 (34 DIM) to 0.11 (280 DIM) across lactation. Phenotypic correlations among many traits including REI and energy balance (EB) differed not only by stage of lactation but also by cow parity. Moderate to strong genetic correlations existed between REI and EB across lactation (ranging from 0.45 to 0.90). Albeit associated with large standard errors, estimated genetic correlations between feed efficiency and reproductive performance were either neutral or favourable suggesting greater genetic merit for feed efficiency does not appear to be antagonistically genetically correlated with reproductive performance. Selection index calculations using the current economic weights in the Irish Economic Breeding Index, and genetic (co)variances estimated in this thesis, indicate that the inclusion of REI in the index with an economic weight of €0.078/UFL will generate animals with improved REI

Genetics and feed efficiency

International audienc

Nutrient Digestibility and Productivity of Bali Cattle Fed Fermented Hymenachne Amplexia­calis Based Rations Supplemented with Leucaena Leucocephala

An experiment was conducted to study the effects of lamtoro (Leucaena leucocephala) leaf supplementation in fermented kumpai grass (Hymenachne amplexia­calis) based rations on the productivity of Bali cattle. Variables measured were dry matter and organic matter intakes, nutrient digestibility (dry matter, organic matter, crude protein, and crude fiber), body weight gain, and feed efficiency. The types of rations were: Ration A= 45% fermented kumpai grass + 40% benggala grass + 15% concentrate + 0% lamtoro leaf, Ration B= 45% fermented kumpai grass + 30% benggala grass + 15% concentrate + 10% lamtoro leaf, Ration C= 45% fermented kumpai grass + 20% benggala grass + 15% concentrate + 20% lamtoro leaf, and Ration D= 45% fermented kumpai grass + 10% benggala grass + 15% concentrate + 30% lamtoro leaf. The supplementation of lamtoro leaf up to 30% into the ration could increase (P<0.05) dry matter and organic matter intakes, and crude protein digestibility. The highest body weight gain and feed efficiency were found in Bali cattle fed ration with 20% lamtoro leaf supplementation. The level of lamtoro leaf supplementation in the ration did not affect the digestibility of dry matter, organic matter, and crude fiber. It was concluded that the supplementation of lamtoro leaf in the ration could increase dry matter, organic matter, and crude protein intakes. Addition of 20% lamtoro leaf gave the best effect on the increased body weight gain and feed efficiency in Bali cattle

Improving Feed Efficiency Through Genetics

Feed efficiency is not a new topic to the beef industry. Historically this topic has been revisited by the industry every 10 to 15 years with little benefit to the producer. The lack of progress in understanding the genetics of feed efficiency stems from the difficulty in trying to accurately measure individual intakes, coupled with extreme costs and a long generation interval. Feed efficiency is difficult to define and needs to be evaluated in the producing female, as well as the growing/finishing animal. Heritability of feed efficiency has been estimated to be moderate, with values ranging from .28-.44. These values indicate that variation among and within beef cattle populations do exist for feed efficiency. This means genetic selection will work as a tool to improve feed efficiency. The main benefit of understanding the genetics of feed efficiency and developing tools to improve efficiency is reduced production costs. With 70-80% of the total variable costs in beef production being feed costs, the slightest improvement in feed efficiency will have a significant impact in profitability in multiple areas of beef production. Technology has developed to a point that we can better measure, record, analyze and implement selection for energy efficiency

Phenotypic evaluation of feed efficiency, growth and carcass traits in native turkeys

Improving feed efficiency decreases feed intake, total cost, and the environmental emission of poultry production. This study aimed to investigate different feed efficiency, growth and carcass traits between high and low feed efficiency birds in Iranian native turkeys. Growth and carcass characteristics of native turkeys were recorded. Four different feed efficiency traits, including feed conversion ratio (FCR), residual feed intake (RFI), residual body weight gain (RG), and residual intake and body weight gain (RIG) were calculated. The phenotypic correlations were calculated among feed efficiency measurements and different growth traits. High and low feed efficiency birds based on FCR were compared for growth and carcass traits. The phenotypic correlation between FCR and RFI was 0.5 and FCR was strongly correlated with RG and RIG. Breast muscle weight of high feed efficiency birds based of FCR was significantly higher than low feed efficiency birds. The results showed that phenotypic selection based on each of the feed efficiency traits will automatically progress the others, however, using FCR can be more straightforward in local farms and results in producing more beneficial turkeys with better growth and carcass features