Thayla Sara Soares Stivari

Viabilidade econômico-financeira de sistemas de produção de cordeiros não desmamados em pastagem com suplementação em cocho ou pasto privativo

The objective was to analyze production costs and profitability of grazing sheep productions systems under three strategies of lambs supplementation: (1) white clover on creep grazing; (2) creep feeding; and (3) not supplemented. Two methods of financial analyses where used: annual (short term) and cash flow (long term). Costs were classified into variable, fixed, operational and total. Results showed that feeding and opportunity cost over investment was the most important production factors at variable and total costs, respectively. System with creep grazing supplementation did not show greater economic financial results over creep feeding supplementation system.

Lamb Production Costs: Analyses of Composition and Elasticities Analysis of Lamb Production Costs

Since lamb is a commodity, producers cannot control the price of the product they sell. Therefore, managing production costs is a necessity. We explored the study of elasticities as a tool for basing decision-making in sheep production, and aimed at investigating the composition and elasticities of lamb production costs, and their influence on the performance of the activity. A representative sheep production farm, designed in a panel meeting, was the base for calculation of lamb production cost. We then performed studies of: i) costs composition, and ii) cost elasticities for prices of inputs and for zootechnical indicators. Variable costs represented 64.15% of total cost, while 21.66% were represented by operational fixed costs, and 14.19% by the income of the factors. As for elasticities to input prices, the opportunity cost of land was the item to which production cost was more sensitive: a 1% increase in its price would cause a 0.2666% increase in lamb cost. Meanwhile, the impact of increasing any technical indicator was significantly higher than the impact of rising input prices. A 1% increase in weight at slaughter, for example, would reduce total cost in 0.91%. The greatest obstacle to economic viability of sheep production under the observed conditions is low technical efficiency. Increased production costs are more related to deficient zootechnical indexes than to high expenses.

Aditivos enzimáticos na alimentação de ruminantes: estratégia para a produção animal

Advances in ruminant nutrition require new strategies for manipulation of rumen fermentation, so that the beneficial effects are enhanced and the deleterious minimized or excluded. Food additives have been used as a strategy, which when added to food, retain, enhance or modify their properties, without affecting its nutritional value. The use of fibrolytic enzymes in ruminant diets has shown promising results, providing improvements in fiber degradability, production indexes and ruminal parameters. The aim of this review is to address the use of additives in ruminant diets, their advances in the last decades and compile results from studies using fibrolytic enzymes in ruminant nutrition. keywords: animal performance, fibrolytic enzyme, nutrition, probiotic, ruminal digestion