The desert environment of Mendoza, Argentina: status and prospects for sustainable beef cattle production

GUEVARA J.C.; GRÜNWALDT, E.G.

Deserts: Flora, Fauna and Environment

Nova Science Publishers Inc.

Lugar: New York; Año: 2010;

The purpose of this chapter was to characterize the environment of Mendoza devoted to beef cattle production and propose a management practice to improve the productivity and profitability of this activity using the forage that could be produced in about 75,000 irrigated hectares uncultivated at present. This practice consists of early weaning beef calves averaging 70-kg live weight at 60-day-old, feeding them balanced commercial feed and alfalfa hay until they reach 100-kg live weight within a period of 45 days. Subsequently, calves graze alfalfa and are supplied maize silage in pens during night confinement until reaching 320-kg live weight over a period of 314 days. Mendoza lies in the central west of the country with 148,827 km2. An important portion of Mendoza falls within the central eastern part of the Monte Phytogeographical Province, the most arid rangeland of the country. The Monte vegetation may take various aspects depending chiefly on its degradation status: dense thickets of small trees, open woodlands and savannas with isolated trees, tall shrublands, low shrublands and bare lands. Floristic resources are used by beef cattle, goats, native and exotic wildlife and other herbivores. South American camelids (Vicugna vicugna and Lama guanicoe) are the most important fauna species of economic use. Exotic fauna is mainly represented by Lepus europaeus. Around 9 million of Mendoza’s hectares could be devoted to livestock production. The beef cattle stock is currently 547,825, of which 49.2 % are cows. Cow–calf operations under rangeland conditions are the dominant production system. Mendoza consumes 464,025 bovines year-1, of which only 7 % are locally finished in cultivated pastures and feedlots. Profitability of the proposed strategy was assessed through the internal rate of return (IRR) and the net present value (NPV). Investments, operating costs, and animal prices were taken at November 2010. The production system that combines early weaning with post-weaning strategies was more profitable than traditional post-weaning production system. For the integrated production system, 378 was the minimum number of animals that permits reaching an IRR higher than the opportunity cost of capital (12%). The NPV obtained per animal, in US$, increased from 1.72 for 378 animals to 1,143.7 for 2,000 animals per year. The cultivated area necessary to feed 100 animals was 14.2 ha (10.6 ha for alfalfa hay and 3.6 for maize silage). Meat productivity was about 1550 kg ha-1 year-1. The use of the uncultivated irrigated area could permit post-weaning production of about 500,000 calves per year to supply the total meat demand of Mendoza.